SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0437 PM CDT Tue Mar 18 2025 Valid 201200Z - 261200Z An active fire weather pattern will continue across much of the central/southern Plains through the extended period with multiple days of Elevated to Critical fire weather expected. ...D3 - Thursday through D4 - Friday, Southern Plains... Winds will shift to become southeasterly on D3-Thursday, but conditions look to remain very dry and breezy, with slow moisture return late D3/Thursday into D4/Friday. Lee troughing will strengthen, with Critical fire weather conditions possible across eastern New Mexico into the Texas Panhandle. Some critical meteorological conditions will extend into portions of southern Colorado and the Oklahoma Panhandle but precipitation D2 - Wednesday is expected across these areas. A 70 percent area was added in across eastern New Mexico into the Texas Panhandle with this outlook. A belt of strong west-southwesterly flow aloft will overspread the central Plains again on Friday with surface low development expected across eastern Colorado. This system has trended further north and faster, leading to reduction of some of the D4 - Friday 70 percent probabilities with a shift northward in the 40 percent probabilities. ...D5- Saturday through D8 Tuesday Southern Plains... Weak surface troughing and periods of breezy post frontal northwesterly flow will keep periods of windy/dry conditions possible across the central/southern High Plains each day through the end of the extended. There is low confidence in strength/track of a shortwave tracking across the central/high Plains into the Midwest on D5 - Saturday. Depending on the evolution of this feature, some Critical conditions may occur across the central high Plains again. A small 40 percent area was added on D5 with this outlook. ..Thornton.. 03/18/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Tue Mar 18 2025 Valid 191200Z - 201200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHERN NEW MEXICO INTO CENTRAL TO SOUTHERN TEXAS... ...Southern and Central Plains... Adjustments were made to the Elevated across western Oklahoma into central Oklahoma to account for overlap of D1/D2 fire weather concerns across western and central Oklahoma into the Texas Panhandle. Some portion of this area likely be removed in subsequent outlooks as conditions improve Wednesday morning/afternoon. Elevated to locally Critical conditions will develop again across the Texas Panhandle tomorrow afternoon as post-frontal northwesterly flow overlaps continued dry conditions, though temperatures will hover near the mid to upper 50s. The Critical area was expanded northward into southern New Mexico to account for latest trends and updated information on fuels. Temperatures will be cooling across this region, however post frontal winds will remain strong with ERCs around the 90th percentile. ...West Virginia, Southern Pennsylvania, Portions of the Appalachians... An Elevated delineation was added across portions of the Appalachians across eastern Tennessee/North Carolina. A very dry air mass will be in place across this region amid breezy southerly winds. Elevated to locally critical conditions are expected. Latest fuels guidance in these regions suggests fuels will support fire spread. ..Thornton.. 03/18/2025 .PREV DISCUSSION... /ISSUED 0202 AM CDT Tue Mar 18 2025/ ...Synopsis... Critical fire weather conditions are expected to persist across the southern High Plains into central and southern Texas Wednesday afternoon. More regional fire weather concerns are anticipated across parts of the upper OH River Valley. ...Southern Plains... A Pacific cold front attendant to a deep surface cyclone is expected to push east/southeast across the southern Plains late Tuesday night into early Wednesday. In its wake, cool, but very dry air will overspread eastern NM into OK and TX. Temperature reductions will be muted with southward extent, resulting in a swath of RH minimums between 15-25% from eastern NM to eastern TX. Although the surface low will be lifting to the northeast away from the region, a lingering belt of 20-30 mph winds between 850-700 mb will promote breezy conditions at the surface by mid-afternoon. Ensemble guidance shows a strong signal for sustained winds near 20 mph from the Davis Mountains region southeastward towards the Edwards Plateau and Rio Grande Valley, though critical wind speeds may emerge as far north as the lee of the Sacramento mountains. More broadly across TX, wind speeds between 15-20 mph will support an expansive swath of elevated fire weather conditions. ...Upper OH River Valley... Southerly winds are expected to strengthen to 15-20 mph ahead of an approaching surface low across much of the OH River Valley. This will induce a downslope flow regime off the northern slopes of the Appalachians with forecast guidance suggesting RH values will fall into the 20-30% range by mid-afternoon across parts of KY, WV, OH, and PA. Although elevated meteorological conditions may be somewhat expansive, the Elevated risk area is confined to locations that received relatively little rainfall over the past few days and will have a higher probability of receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Tue Mar 18 2025 Valid 191200Z - 201200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHERN NEW MEXICO INTO CENTRAL TO SOUTHERN TEXAS... ...Southern and Central Plains... Adjustments were made to the Elevated across western Oklahoma into central Oklahoma to account for overlap of D1/D2 fire weather concerns across western and central Oklahoma into the Texas Panhandle. Some portion of this area likely be removed in subsequent outlooks as conditions improve Wednesday morning/afternoon. Elevated to locally Critical conditions will develop again across the Texas Panhandle tomorrow afternoon as post-frontal northwesterly flow overlaps continued dry conditions, though temperatures will hover near the mid to upper 50s. The Critical area was expanded northward into southern New Mexico to account for latest trends and updated information on fuels. Temperatures will be cooling across this region, however post frontal winds will remain strong with ERCs around the 90th percentile. ...West Virginia, Southern Pennsylvania, Portions of the Appalachians... An Elevated delineation was added across portions of the Appalachians across eastern Tennessee/North Carolina. A very dry air mass will be in place across this region amid breezy southerly winds. Elevated to locally critical conditions are expected. Latest fuels guidance in these regions suggests fuels will support fire spread. ..Thornton.. 03/18/2025 .PREV DISCUSSION... /ISSUED 0202 AM CDT Tue Mar 18 2025/ ...Synopsis... Critical fire weather conditions are expected to persist across the southern High Plains into central and southern Texas Wednesday afternoon. More regional fire weather concerns are anticipated across parts of the upper OH River Valley. ...Southern Plains... A Pacific cold front attendant to a deep surface cyclone is expected to push east/southeast across the southern Plains late Tuesday night into early Wednesday. In its wake, cool, but very dry air will overspread eastern NM into OK and TX. Temperature reductions will be muted with southward extent, resulting in a swath of RH minimums between 15-25% from eastern NM to eastern TX. Although the surface low will be lifting to the northeast away from the region, a lingering belt of 20-30 mph winds between 850-700 mb will promote breezy conditions at the surface by mid-afternoon. Ensemble guidance shows a strong signal for sustained winds near 20 mph from the Davis Mountains region southeastward towards the Edwards Plateau and Rio Grande Valley, though critical wind speeds may emerge as far north as the lee of the Sacramento mountains. More broadly across TX, wind speeds between 15-20 mph will support an expansive swath of elevated fire weather conditions. ...Upper OH River Valley... Southerly winds are expected to strengthen to 15-20 mph ahead of an approaching surface low across much of the OH River Valley. This will induce a downslope flow regime off the northern slopes of the Appalachians with forecast guidance suggesting RH values will fall into the 20-30% range by mid-afternoon across parts of KY, WV, OH, and PA. Although elevated meteorological conditions may be somewhat expansive, the Elevated risk area is confined to locations that received relatively little rainfall over the past few days and will have a higher probability of receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Mar 18 2025 Valid 182000Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT ACROSS PARTS OF SOUTHEASTERN NEBRASKA THROUGH SOUTHWESTERN AND CENTRAL IOWA... ...SUMMARY... Isolated, marginally severe hail is possible by late tonight in a corridor from north central Kansas through central Iowa. ...20Z Update... The Marginal risk area was expanded slightly eastward into east-central Iowa. Any elevated thunderstorm clusters that evolve and track east-northeastward along the warm front (as indicated by the latest MPAS runs) will pose an isolated severe-hail risk into this area. For additional details, see the previous discussion below. ..Weinman.. 03/18/2025 .PREV DISCUSSION... /ISSUED 1123 AM CDT Tue Mar 18 2025/ ...Discussion... Much of the nation remains under the influence of one prominent belt of westerlies emanating from the northern mid-latitude Pacific. Within this regime, mid-level troughing is in the process of digging across the Intermountain West and Rockies. This includes one significant embedded smaller-scale perturbation approaching the southern Rockies, which is forecast to accelerate east-northeastward across the south central Great Plains by late tonight. Models indicate that this will be accompanied by a strong mid/upper jet streak, including a core intensifying in excess of 100 kt around 500 mb, nosing across the Texas Panhandle vicinity through the lower Missouri Valley from early this evening through 12Z Wednesday. It appears that this may be accompanied by substantive further deepening of a developing low across central through northeastern Kansas, within already deep surface troughing now present across the central/southern Great Plains into lower/middle Missouri Valley. In the wake of the prior cyclone which impacted much of the central and eastern U.S. and Gulf Basin late last week into the weekend, boundary-layer moistening across the western Gulf is underway, but still only supportive of rather modest low-level moistening across the Texas Gulf coast into southeastern Great Plains (including low to mid 50s F surface dew points). It appears that this will reach portions of the lower central Great Plains into Upper Midwest late this evening through early Wednesday. However, relatively warm and dry air in the lower/mid-troposphere, associated with a broad plume of elevated mixed-layer air overspreading the central/southern Great Plains and middle/lower Mississippi Valley, will tend to impede an appreciable risk for thunderstorm development. ...Central Great Plains toward the Upper Midwest... Perhaps as early as late this evening, into the overnight hours, model output continues to indicate that strengthening mid/upper forcing for ascent, coupled with better low-level moisture return, will overcome the inhibition and support a corridor of thunderstorm development. This likely will be focused within strengthening lower/mid-tropospheric warm advection, along a frontal zone extending to the east-northeast of the surface cyclone, across southeastern Nebraska through central Iowa by late tonight. Based at least on the latest NAM, it appears that the more sustained and stronger thunderstorm development may initiate as early as late evening near/east-northeast of the Concordia KS vicinity, before spreading northeastward. This seems likely to occur as convection begins to become increasingly rooted below the 700 mb level, closer to 850 mb, with soundings perhaps becoming characterized by "loaded gun" thermodynamic profiles above the near-surface stable layer. Although most unstable CAPE may mostly peak in the 500-750 J/kg range, stronger cells may become conducive to marginally severe hail, aided by strong shear in the convective layer. The potential for strong surface gusts is somewhat more uncertain. Although the risk for strong downdrafts to reach the surface appears negligible, gravity wave induced surface pressure perturbations supportive of gusty winds may not be entirely out of the question. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Mar 18 2025 Valid 182000Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT ACROSS PARTS OF SOUTHEASTERN NEBRASKA THROUGH SOUTHWESTERN AND CENTRAL IOWA... ...SUMMARY... Isolated, marginally severe hail is possible by late tonight in a corridor from north central Kansas through central Iowa. ...20Z Update... The Marginal risk area was expanded slightly eastward into east-central Iowa. Any elevated thunderstorm clusters that evolve and track east-northeastward along the warm front (as indicated by the latest MPAS runs) will pose an isolated severe-hail risk into this area. For additional details, see the previous discussion below. ..Weinman.. 03/18/2025 .PREV DISCUSSION... /ISSUED 1123 AM CDT Tue Mar 18 2025/ ...Discussion... Much of the nation remains under the influence of one prominent belt of westerlies emanating from the northern mid-latitude Pacific. Within this regime, mid-level troughing is in the process of digging across the Intermountain West and Rockies. This includes one significant embedded smaller-scale perturbation approaching the southern Rockies, which is forecast to accelerate east-northeastward across the south central Great Plains by late tonight. Models indicate that this will be accompanied by a strong mid/upper jet streak, including a core intensifying in excess of 100 kt around 500 mb, nosing across the Texas Panhandle vicinity through the lower Missouri Valley from early this evening through 12Z Wednesday. It appears that this may be accompanied by substantive further deepening of a developing low across central through northeastern Kansas, within already deep surface troughing now present across the central/southern Great Plains into lower/middle Missouri Valley. In the wake of the prior cyclone which impacted much of the central and eastern U.S. and Gulf Basin late last week into the weekend, boundary-layer moistening across the western Gulf is underway, but still only supportive of rather modest low-level moistening across the Texas Gulf coast into southeastern Great Plains (including low to mid 50s F surface dew points). It appears that this will reach portions of the lower central Great Plains into Upper Midwest late this evening through early Wednesday. However, relatively warm and dry air in the lower/mid-troposphere, associated with a broad plume of elevated mixed-layer air overspreading the central/southern Great Plains and middle/lower Mississippi Valley, will tend to impede an appreciable risk for thunderstorm development. ...Central Great Plains toward the Upper Midwest... Perhaps as early as late this evening, into the overnight hours, model output continues to indicate that strengthening mid/upper forcing for ascent, coupled with better low-level moisture return, will overcome the inhibition and support a corridor of thunderstorm development. This likely will be focused within strengthening lower/mid-tropospheric warm advection, along a frontal zone extending to the east-northeast of the surface cyclone, across southeastern Nebraska through central Iowa by late tonight. Based at least on the latest NAM, it appears that the more sustained and stronger thunderstorm development may initiate as early as late evening near/east-northeast of the Concordia KS vicinity, before spreading northeastward. This seems likely to occur as convection begins to become increasingly rooted below the 700 mb level, closer to 850 mb, with soundings perhaps becoming characterized by "loaded gun" thermodynamic profiles above the near-surface stable layer. Although most unstable CAPE may mostly peak in the 500-750 J/kg range, stronger cells may become conducive to marginally severe hail, aided by strong shear in the convective layer. The potential for strong surface gusts is somewhat more uncertain. Although the risk for strong downdrafts to reach the surface appears negligible, gravity wave induced surface pressure perturbations supportive of gusty winds may not be entirely out of the question. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 PM CDT Tue Mar 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm development will be possible on Thursday from parts of the Mid-Atlantic and northern Rockies. A severe threat is not expected. ...Synopsis... A progressive upper pattern will be in place over the CONUS on Thursday, with a mid-level trough impinging on the West Coast as another mid-level trough approaches the central Rockies and a third upper trough ejects into the Atlantic. Though the central U.S. trough will encourage strong lee troughing over the Plains, Gulf moisture will be scoured from the previous departing trough and associated surface cold front. Furthermore, surface high pressure will overspread much of the eastern and western CONUS. The net result will be widespread, stable conditions, with negligible thunderstorm potential over much of the U.S., with two exceptions. First, cold temperatures aloft and associated steep mid-level lapse rates accompanying the aforementioned Rockies upper trough will overspread portions of the northern Rockies, promoting enough lift and buoyancy (albeit scant) to support a couple of lightning flashes. Second, across the Mid Atlantic, just enough moisture to foster marginal buoyancy ahead of a surface trough/cold front will support isolated thunderstorm development before the cold front moves offshore. ..Squitieri.. 03/18/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 PM CDT Tue Mar 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm development will be possible on Thursday from parts of the Mid-Atlantic and northern Rockies. A severe threat is not expected. ...Synopsis... A progressive upper pattern will be in place over the CONUS on Thursday, with a mid-level trough impinging on the West Coast as another mid-level trough approaches the central Rockies and a third upper trough ejects into the Atlantic. Though the central U.S. trough will encourage strong lee troughing over the Plains, Gulf moisture will be scoured from the previous departing trough and associated surface cold front. Furthermore, surface high pressure will overspread much of the eastern and western CONUS. The net result will be widespread, stable conditions, with negligible thunderstorm potential over much of the U.S., with two exceptions. First, cold temperatures aloft and associated steep mid-level lapse rates accompanying the aforementioned Rockies upper trough will overspread portions of the northern Rockies, promoting enough lift and buoyancy (albeit scant) to support a couple of lightning flashes. Second, across the Mid Atlantic, just enough moisture to foster marginal buoyancy ahead of a surface trough/cold front will support isolated thunderstorm development before the cold front moves offshore. ..Squitieri.. 03/18/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Tue Mar 18 2025 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF EASTERN ILLINOIS INTO WESTERN INDIANA... ...SUMMARY... Scattered severe thunderstorms are possible on Wednesday across parts of eastern Illinois and western Indiana from mid-afternoon to early evening. Severe gusts and hail will be the primary threats, though a couple of tornadoes are also possible. ...Synopsis... A potent mid-level trough will traverse the Plains and overspread the MS Valley, encouraging an intense surface cyclone to track from the Mid-MO Valley to the Great Lakes on Wednesday. Despite the intensity of the surface low and accompanying upper support from the mid-level trough, buoyancy is expected to remain scant within the warm sector given very limited low-level moisture. Nonetheless, strong isallobaric surface flow and the presence of a low-level jet ahead of the surface cyclone will allow for the northward advection of some moisture (however marginal) to support low-topped storms amid a highly sheared airmass. Some of these storms may become strong to occasionally severe, particularly in the Midwest toward the OH Valley. ...Midwest to OH Valley... Modest clearing and associated insolation ahead of the surface low will promote modest boundary-layer mixing and destabilization amid marginal moisture. Surface dewpoints of at least 50 F with the aforementioned heating, beneath 7-8 C/km mid-level lapse rates, will support 250-750 J/kg SBCAPE by mid to late afternoon. During this time frame, surface winds are expected to be backed from the southeast, with a 50+ kt southwesterly low-level jet contributing to substantial veering/strengthening of the low-level wind profile. Somewhat curved and elongated hodographs will contribute to over 300 m2/s2 of sfc-3km SRH. Given marginal buoyancy, an arcing band of low-topped supercells will precede the surface low, accompanied by a damaging gust/hail threat. Furthermore, the strong low-level shear, and increasing low-level vertical vorticity (as the surface low approaches) will also foster a risk for at least an isolated tornado. There are some discrepancies among guidance members regarding the degree of low-level destabilization across portions of the OH Valley ahead of the surface low. RAP forecast soundings show mid 50s F surface dewpoints beneath 8+ C/km mid-level rates, supporting a relatively higher tornado threat compared to NAM, which shows low 50s F dewpoints overspread by 6.5-7.5 C/km lapse rates. Higher tornado probabilities may be needed in future outlooks if guidance consensus depicts more boundary-layer instability. ...TN Valley into the Southeast... At least isolated thunderstorms are expected to develop by late afternoon into evening along the surface cold front, which will sweep across the TN Valley/Southeast areas. These storms are expected to be low-topped in nature, but highly sheared (given a 40+ kt southwesterly low-level jet, beneath 80+ kts of southwesterly 500 mb flow, contributing to 50-70 kts of effective bulk shear). In addition to marginal low-level moisture, modest warming in the 850-700 mb layer will also limit thunderstorm intensity and coverage. Given strong low-level and deep-layer directional and speed shear, any storms that can become established and sustained may become supercellular, posing mainly a risk for a few instances of damaging gusts/hail. ..Squitieri.. 03/18/2025 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1150 AM CDT Tue Mar 18 2025 Valid 181700Z - 191200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR FAR SOUTHEAST NEW MEXICO INTO THE TEXAS PANHANDLE AND WESTERN OKLAHOMA... ...CRITICAL FIRE WEATHER AREA FOR MUCH OF THE SOUTHERN HIGH PLAINS... The Extremely Critical fire weather area was expanded further west into west-central New Mexico with this update. This is to account for updated status of fuels across northern New Mexico, where ERCs are now in the 75th-90th percentile. Current surface observations show areas of Extremely Critical conditions ongoing near the lee of some of the high terrain across western New Mexico. Scattered cloud cover is observed across portions of the Texas Panhandle into western Oklahoma, though some mixing and clearing has occurred. HREF guidance suggests cloud cover across the Extremely Critical will decrease into the afternoon, with mostly sunny conditions by 20-21z. Through the late afternoon into the evening, models continue to suggest that the dryline will advance eastward with relative humidity dropping across western/central Oklahoma. In addition, winds will shift to become more westerly through time. The Elevated was expanded further south into south-central Texas in alignment with trends in observations and model guidance. See previous discussion below for more information. ..Thornton.. 03/18/2025 .PREV DISCUSSION... /ISSUED 1259 AM CDT Tue Mar 18 2025/ ...Synopsis... Extremely critical fire weather conditions are expected today across parts of the southern High Plains and into western Oklahoma. More broadly, elevated to critical fire weather conditions are expected across much of the southern and central Plains where fuels remain critical dry after minimal rainfall over the past week. 05 UTC surface observations show surface pressure falls across eastern CO/western KS as a surface low begins to organized ahead of an approaching upper-level trough. Rapid cyclogenesis is anticipated through the afternoon across northwest KS, resulting in a robust low-level mass response across the Plains. ...Southern High Plains... Recent surface observations show 5-15 F dewpoints in place across southeast NM and southwest TX. The 00z MAF sounding sampled even drier air within the residual boundary layer that will quickly mix to the surface by early afternoon. Widespread 25-30 mph gradient winds are expected across much of the southern High Plains with sustained 30-35 mph winds likely under the low-level thermal ridge due to a combination of terrain enhancements along/off the Caprock and maximized boundary-layer mixing. The Extremely Critical risk area aligns with the forecast location of the low-level thermal ridge axis by late afternoon to the west of the dryline. Latest guidance continues to suggest that the dryline will remain across western OK into northwest TX, but extreme/near-extreme fire weather conditions may spread further east if guidance is under-mixing the eastward progression of this boundary. Winds are expected to strengthen slightly and shift from southwest to westerly around/after 21 UTC as a Pacific cold front pushes into the southern High Plains in tandem with the mid-level jet. The combination of increasing wind gusts (possibly up to 50-60 mph) and the directional change may support rapid fire spread with any ongoing fires. ...Central/Eastern TX, OK, KS into MO... To the east of the dryline, a broad swath of 15-25 mph winds is expected across central TX, OK, KS, and adjacent portions of MO. Shallow low-level moisture along the TX Coastal Plain and dewpoints in the 40s off the Gulf coast suggest that moisture return ahead of the dryline will be poor. Filtered diurnal heating will likely support sufficient boundary-layer mixing to promote RH reductions into the teens and 20s and 15-25 mph winds ahead of the dryline. Forecast guidance typically under mixes the boundary layer in these regime, resulting in more widespread elevated/critical fire weather conditions than otherwise predicted. As such, the Elevated/Critical risk areas have been expanded to account for this bias. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1123 AM CDT Tue Mar 18 2025 Valid 181630Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT ACROSS PARTS OF SOUTHEASTERN NEBRASKA THROUGH SOUTHWESTERN AND CENTRAL IOWA... ...SUMMARY... Isolated, marginally severe hail is possible by late tonight in a corridor from north central Kansas through central Iowa. ...Discussion... Much of the nation remains under the influence of one prominent belt of westerlies emanating from the northern mid-latitude Pacific. Within this regime, mid-level troughing is in the process of digging across the Intermountain West and Rockies. This includes one significant embedded smaller-scale perturbation approaching the southern Rockies, which is forecast to accelerate east-northeastward across the south central Great Plains by late tonight. Models indicate that this will be accompanied by a strong mid/upper jet streak, including a core intensifying in excess of 100 kt around 500 mb, nosing across the Texas Panhandle vicinity through the lower Missouri Valley from early this evening through 12Z Wednesday. It appears that this may be accompanied by substantive further deepening of a developing low across central through northeastern Kansas, within already deep surface troughing now present across the central/southern Great Plains into lower/middle Missouri Valley. In the wake of the prior cyclone which impacted much of the central and eastern U.S. and Gulf Basin late last week into the weekend, boundary-layer moistening across the western Gulf is underway, but still only supportive of rather modest low-level moistening across the Texas Gulf coast into southeastern Great Plains (including low to mid 50s F surface dew points). It appears that this will reach portions of the lower central Great Plains into Upper Midwest late this evening through early Wednesday. However, relatively warm and dry air in the lower/mid-troposphere, associated with a broad plume of elevated mixed-layer air overspreading the central/southern Great Plains and middle/lower Mississippi Valley, will tend to impede an appreciable risk for thunderstorm development. ...Central Great Plains toward the Upper Midwest... Perhaps as early as late this evening, into the overnight hours, model output continues to indicate that strengthening mid/upper forcing for ascent, coupled with better low-level moisture return, will overcome the inhibition and support a corridor of thunderstorm development. This likely will be focused within strengthening lower/mid-tropospheric warm advection, along a frontal zone extending to the east-northeast of the surface cyclone, across southeastern Nebraska through central Iowa by late tonight. Based at least on the latest NAM, it appears that the more sustained and stronger thunderstorm development may initiate as early as late evening near/east-northeast of the Concordia KS vicinity, before spreading northeastward. This seems likely to occur as convection begins to become increasingly rooted below the 700 mb level, closer to 850 mb, with soundings perhaps becoming characterized by "loaded gun" thermodynamic profiles above the near-surface stable layer. Although most unstable CAPE may mostly peak in the 500-750 J/kg range, stronger cells may become conducive to marginally severe hail, aided by strong shear in the convective layer. The potential for strong surface gusts is somewhat more uncertain. Although the risk for strong downdrafts to reach the surface appears negligible, gravity wave induced surface pressure perturbations supportive of gusty winds may not be entirely out of the question. ..Kerr/Bunting.. 03/18/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1123 AM CDT Tue Mar 18 2025 Valid 181630Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT ACROSS PARTS OF SOUTHEASTERN NEBRASKA THROUGH SOUTHWESTERN AND CENTRAL IOWA... ...SUMMARY... Isolated, marginally severe hail is possible by late tonight in a corridor from north central Kansas through central Iowa. ...Discussion... Much of the nation remains under the influence of one prominent belt of westerlies emanating from the northern mid-latitude Pacific. Within this regime, mid-level troughing is in the process of digging across the Intermountain West and Rockies. This includes one significant embedded smaller-scale perturbation approaching the southern Rockies, which is forecast to accelerate east-northeastward across the south central Great Plains by late tonight. Models indicate that this will be accompanied by a strong mid/upper jet streak, including a core intensifying in excess of 100 kt around 500 mb, nosing across the Texas Panhandle vicinity through the lower Missouri Valley from early this evening through 12Z Wednesday. It appears that this may be accompanied by substantive further deepening of a developing low across central through northeastern Kansas, within already deep surface troughing now present across the central/southern Great Plains into lower/middle Missouri Valley. In the wake of the prior cyclone which impacted much of the central and eastern U.S. and Gulf Basin late last week into the weekend, boundary-layer moistening across the western Gulf is underway, but still only supportive of rather modest low-level moistening across the Texas Gulf coast into southeastern Great Plains (including low to mid 50s F surface dew points). It appears that this will reach portions of the lower central Great Plains into Upper Midwest late this evening through early Wednesday. However, relatively warm and dry air in the lower/mid-troposphere, associated with a broad plume of elevated mixed-layer air overspreading the central/southern Great Plains and middle/lower Mississippi Valley, will tend to impede an appreciable risk for thunderstorm development. ...Central Great Plains toward the Upper Midwest... Perhaps as early as late this evening, into the overnight hours, model output continues to indicate that strengthening mid/upper forcing for ascent, coupled with better low-level moisture return, will overcome the inhibition and support a corridor of thunderstorm development. This likely will be focused within strengthening lower/mid-tropospheric warm advection, along a frontal zone extending to the east-northeast of the surface cyclone, across southeastern Nebraska through central Iowa by late tonight. Based at least on the latest NAM, it appears that the more sustained and stronger thunderstorm development may initiate as early as late evening near/east-northeast of the Concordia KS vicinity, before spreading northeastward. This seems likely to occur as convection begins to become increasingly rooted below the 700 mb level, closer to 850 mb, with soundings perhaps becoming characterized by "loaded gun" thermodynamic profiles above the near-surface stable layer. Although most unstable CAPE may mostly peak in the 500-750 J/kg range, stronger cells may become conducive to marginally severe hail, aided by strong shear in the convective layer. The potential for strong surface gusts is somewhat more uncertain. Although the risk for strong downdrafts to reach the surface appears negligible, gravity wave induced surface pressure perturbations supportive of gusty winds may not be entirely out of the question. ..Kerr/Bunting.. 03/18/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue Mar 18 2025 Valid 181300Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE TONIGHT FROM EASTERN NE INTO IA... ...SUMMARY... Isolated, marginally severe hail is possible late tonight from eastern Nebraska across much of Iowa. ...Eastern NE/IA late tonight and early Wednesday... In advance of a pronounced midlevel shortwave trough over UT/northern AZ this morning, a surface lee cyclone will deepen across western KS and then move to far northwest MO by early Wednesday. Moisture return in the warm sector of this deepening cyclone will be limited by a prior frontal passage across the Gulf/northwest Caribbean, with only a narrow corridor of low-mid 50s boundary-layer dewpoints expected from eastern OK to far northwest MO. Though the warm sector will remain capped through the period, there could be sufficient ascent/moistening for elevated thunderstorm development by 06-12z from eastern NE across IA. Steep midlevel lapse rates and relatively cold midlevel temperatures will contribute to MUCAPE of 500-750 J/kg and the potential for isolated large hail (a few instances near 1 inch diameter) with elevated convection to the cool side of a baroclinic zone across eastern NE/IA. ..Thompson/Dean.. 03/18/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue Mar 18 2025 Valid 181300Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE TONIGHT FROM EASTERN NE INTO IA... ...SUMMARY... Isolated, marginally severe hail is possible late tonight from eastern Nebraska across much of Iowa. ...Eastern NE/IA late tonight and early Wednesday... In advance of a pronounced midlevel shortwave trough over UT/northern AZ this morning, a surface lee cyclone will deepen across western KS and then move to far northwest MO by early Wednesday. Moisture return in the warm sector of this deepening cyclone will be limited by a prior frontal passage across the Gulf/northwest Caribbean, with only a narrow corridor of low-mid 50s boundary-layer dewpoints expected from eastern OK to far northwest MO. Though the warm sector will remain capped through the period, there could be sufficient ascent/moistening for elevated thunderstorm development by 06-12z from eastern NE across IA. Steep midlevel lapse rates and relatively cold midlevel temperatures will contribute to MUCAPE of 500-750 J/kg and the potential for isolated large hail (a few instances near 1 inch diameter) with elevated convection to the cool side of a baroclinic zone across eastern NE/IA. ..Thompson/Dean.. 03/18/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Tue Mar 18 2025 Valid 211200Z - 261200Z ...DISCUSSION... ...Friday/Day 4 to Saturday/Day 5... On Friday and Saturday, a shortwave mid-level trough will move eastward from the Great Plains to the Eastern Seaboard, as a long fetch of west-northwest flow develops over much of the continental U.S. Isolated convection may develop ahead of the trough, but instability will likely be insufficient for a severe threat. In the wake of this system, low-level moisture return will begin along the western Gulf Coast. By Saturday, surface dewpoints are expected to be the upper 50s and lower 60s F over the Texas and Louisiana Coastal Plain. ...Sunday/Day 6 to Tuesday/Day 8.... On Sunday, moisture advection is forecast to increase over eastern parts of the southern Plains into the Ark-La-Tex. A mid-level trough is forecast to move across the central U.S. Ahead of the trough, moderate instability is forecast to develop across much of a moist airmass located from the southeastern third of Texas northeastward into the Ark-La-Tex. On Sunday, thunderstorms with a threat for isolated large hail and severe gusts are expected to develop along the northern edge of the moist sector, with a complex of storms moving southeastward across the Sabine and lower Mississippi Valleys overnight. On Monday and Tuesday, the mid-level trough is forecast to move into the eastern U.S., as a cold front advances southward to near the Gulf Coast. Although isolated storms could develop in the southern Gulf Coast states, limited large-scale ascent is expected to be problematic concerning an organized severe threat. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Tue Mar 18 2025 Valid 211200Z - 261200Z ...DISCUSSION... ...Friday/Day 4 to Saturday/Day 5... On Friday and Saturday, a shortwave mid-level trough will move eastward from the Great Plains to the Eastern Seaboard, as a long fetch of west-northwest flow develops over much of the continental U.S. Isolated convection may develop ahead of the trough, but instability will likely be insufficient for a severe threat. In the wake of this system, low-level moisture return will begin along the western Gulf Coast. By Saturday, surface dewpoints are expected to be the upper 50s and lower 60s F over the Texas and Louisiana Coastal Plain. ...Sunday/Day 6 to Tuesday/Day 8.... On Sunday, moisture advection is forecast to increase over eastern parts of the southern Plains into the Ark-La-Tex. A mid-level trough is forecast to move across the central U.S. Ahead of the trough, moderate instability is forecast to develop across much of a moist airmass located from the southeastern third of Texas northeastward into the Ark-La-Tex. On Sunday, thunderstorms with a threat for isolated large hail and severe gusts are expected to develop along the northern edge of the moist sector, with a complex of storms moving southeastward across the Sabine and lower Mississippi Valleys overnight. On Monday and Tuesday, the mid-level trough is forecast to move into the eastern U.S., as a cold front advances southward to near the Gulf Coast. Although isolated storms could develop in the southern Gulf Coast states, limited large-scale ascent is expected to be problematic concerning an organized severe threat. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 AM CDT Tue Mar 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm development will be possible on Thursday from parts of the Mid-Atlantic southward into eastern North Carolina. A severe threat is not expected. ...DISCUSSION... A pre-frontal trough will move from the Appalachians to the Atlantic Coastal plains on Thursday, as an associated mid-level trough moves through the Ohio and Tennessee Valleys. Low-topped convection is forecast to develop near the pre-frontal trough in the afternoon. Isolated thunderstorms will be possible along an axis of strong low-level flow from the Mid-Atlantic southward into eastern North Carolina, mainly during the mid to late afternoon. However, MUCAPE is forecast to remain below 200 J/kg along the instability axis, which should limit the severe potential. ..Broyles.. 03/18/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 AM CDT Tue Mar 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm development will be possible on Thursday from parts of the Mid-Atlantic southward into eastern North Carolina. A severe threat is not expected. ...DISCUSSION... A pre-frontal trough will move from the Appalachians to the Atlantic Coastal plains on Thursday, as an associated mid-level trough moves through the Ohio and Tennessee Valleys. Low-topped convection is forecast to develop near the pre-frontal trough in the afternoon. Isolated thunderstorms will be possible along an axis of strong low-level flow from the Mid-Atlantic southward into eastern North Carolina, mainly during the mid to late afternoon. However, MUCAPE is forecast to remain below 200 J/kg along the instability axis, which should limit the severe potential. ..Broyles.. 03/18/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0202 AM CDT Tue Mar 18 2025 Valid 191200Z - 201200Z ...CRITICAL FIRE WEATHER AREA FOR CENTRAL TO SOUTHERN TEXAS... ...Synopsis... Critical fire weather conditions are expected to persist across the southern High Plains into central and southern Texas Wednesday afternoon. More regional fire weather concerns are anticipated across parts of the upper OH River Valley. ...Southern Plains... A Pacific cold front attendant to a deep surface cyclone is expected to push east/southeast across the southern Plains late Tuesday night into early Wednesday. In its wake, cool, but very dry air will overspread eastern NM into OK and TX. Temperature reductions will be muted with southward extent, resulting in a swath of RH minimums between 15-25% from eastern NM to eastern TX. Although the surface low will be lifting to the northeast away from the region, a lingering belt of 20-30 mph winds between 850-700 mb will promote breezy conditions at the surface by mid-afternoon. Ensemble guidance shows a strong signal for sustained winds near 20 mph from the Davis Mountains region southeastward towards the Edwards Plateau and Rio Grande Valley, though critical wind speeds may emerge as far north as the lee of the Sacramento mountains. More broadly across TX, wind speeds between 15-20 mph will support an expansive swath of elevated fire weather conditions. ...Upper OH River Valley... Southerly winds are expected to strengthen to 15-20 mph ahead of an approaching surface low across much of the OH River Valley. This will induce a downslope flow regime off the northern slopes of the Appalachians with forecast guidance suggesting RH values will fall into the 20-30% range by mid-afternoon across parts of KY, WV, OH, and PA. Although elevated meteorological conditions may be somewhat expansive, the Elevated risk area is confined to locations that received relatively little rainfall over the past few days and will have a higher probability of receptive fuels. ..Moore.. 03/18/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0202 AM CDT Tue Mar 18 2025 Valid 191200Z - 201200Z ...CRITICAL FIRE WEATHER AREA FOR CENTRAL TO SOUTHERN TEXAS... ...Synopsis... Critical fire weather conditions are expected to persist across the southern High Plains into central and southern Texas Wednesday afternoon. More regional fire weather concerns are anticipated across parts of the upper OH River Valley. ...Southern Plains... A Pacific cold front attendant to a deep surface cyclone is expected to push east/southeast across the southern Plains late Tuesday night into early Wednesday. In its wake, cool, but very dry air will overspread eastern NM into OK and TX. Temperature reductions will be muted with southward extent, resulting in a swath of RH minimums between 15-25% from eastern NM to eastern TX. Although the surface low will be lifting to the northeast away from the region, a lingering belt of 20-30 mph winds between 850-700 mb will promote breezy conditions at the surface by mid-afternoon. Ensemble guidance shows a strong signal for sustained winds near 20 mph from the Davis Mountains region southeastward towards the Edwards Plateau and Rio Grande Valley, though critical wind speeds may emerge as far north as the lee of the Sacramento mountains. More broadly across TX, wind speeds between 15-20 mph will support an expansive swath of elevated fire weather conditions. ...Upper OH River Valley... Southerly winds are expected to strengthen to 15-20 mph ahead of an approaching surface low across much of the OH River Valley. This will induce a downslope flow regime off the northern slopes of the Appalachians with forecast guidance suggesting RH values will fall into the 20-30% range by mid-afternoon across parts of KY, WV, OH, and PA. Although elevated meteorological conditions may be somewhat expansive, the Elevated risk area is confined to locations that received relatively little rainfall over the past few days and will have a higher probability of receptive fuels. ..Moore.. 03/18/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Tue Mar 18 2025 Valid 181200Z - 191200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR FAR SOUTHEAST NEW MEXICO INTO THE TEXAS PANHANDLE AND WESTERN OKLAHOMA... ...CRITICAL FIRE WEATHER AREA FOR MUCH OF THE SOUTHERN HIGH PLAINS... ...Synopsis... Extremely critical fire weather conditions are expected today across parts of the southern High Plains and into western Oklahoma. More broadly, elevated to critical fire weather conditions are expected across much of the southern and central Plains where fuels remain critical dry after minimal rainfall over the past week. 05 UTC surface observations show surface pressure falls across eastern CO/western KS as a surface low begins to organized ahead of an approaching upper-level trough. Rapid cyclogenesis is anticipated through the afternoon across northwest KS, resulting in a robust low-level mass response across the Plains. ...Southern High Plains... Recent surface observations show 5-15 F dewpoints in place across southeast NM and southwest TX. The 00z MAF sounding sampled even drier air within the residual boundary layer that will quickly mix to the surface by early afternoon. Widespread 25-30 mph gradient winds are expected across much of the southern High Plains with sustained 30-35 mph winds likely under the low-level thermal ridge due to a combination of terrain enhancements along/off the Caprock and maximized boundary-layer mixing. The Extremely Critical risk area aligns with the forecast location of the low-level thermal ridge axis by late afternoon to the west of the dryline. Latest guidance continues to suggest that the dryline will remain across western OK into northwest TX, but extreme/near-extreme fire weather conditions may spread further east if guidance is under-mixing the eastward progression of this boundary. Winds are expected to strengthen slightly and shift from southwest to westerly around/after 21 UTC as a Pacific cold front pushes into the southern High Plains in tandem with the mid-level jet. The combination of increasing wind gusts (possibly up to 50-60 mph) and the directional change may support rapid fire spread with any ongoing fires. ...Central/Eastern TX, OK, KS into MO... To the east of the dryline, a broad swath of 15-25 mph winds is expected across central TX, OK, KS, and adjacent portions of MO. Shallow low-level moisture along the TX Coastal Plain and dewpoints in the 40s off the Gulf coast suggest that moisture return ahead of the dryline will be poor. Filtered diurnal heating will likely support sufficient boundary-layer mixing to promote RH reductions into the teens and 20s and 15-25 mph winds ahead of the dryline. Forecast guidance typically under mixes the boundary layer in these regime, resulting in more widespread elevated/critical fire weather conditions than otherwise predicted. As such, the Elevated/Critical risk areas have been expanded to account for this bias. ..Moore.. 03/18/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more