SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0218 PM CDT Wed Oct 30 2024 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER THE SOUTHERN HIGH PLAINS... ...SUMMARY... A few strong storms capable of producing marginal hail are expected to develop Friday night over the southern High Plain region. ...Synopsis... Amplification of the upper flow field across the western and central U.S. is forecast, as mid-level short-wave energy on the western side of a low near Vancouver Island digs south-southeastward across the eastern Pacific toward California. This will result in amplification of cyclonic flow over the West and, in response, increased ridging/anticyclonic flow over the central states. At the surface, high pressure will prevail in the wake of a cold front expected to move eastward across New England through the day, while trailing west-to-east across the Carolinas and Gulf Coast States, and into the southern Plains. Meanwhile over the West, a cold front is forecast to advance across the northwestern states and eventually into the Great Basin, in response to the digging upper system. ...Southern High Plains... Development of scattered/elevated storms is expected overnight across the southern High Plains area, within a zone of low-level warm advection near and north of the remnant surface baroclinic zone. Rather steep lapse rates aloft will contribute to ample CAPE, while moderate southwesterly mid-level flow will allow sufficient cloud-layer shear for a few stronger updrafts. This suggests potential for hail near or in excess of severe levels with these potentially stronger storms. ..Goss.. 10/30/2024 Read more

WW 0694 Status Updates
STATUS FOR WATCH 0694 HAS NOT BEEN ISSUED YET Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Wed Oct 30 2024 Valid 311200Z - 011200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN LOWER MICHIGAN SOUTHWESTWARD TO NORTHEASTERN TEXAS/NORTHERN LOUISIANA... ...SUMMARY... Locally strong storms -- a couple of which may produce marginally severe gusts -- will be possible Thursday morning and afternoon, from the Midwest to northeastern Texas/northern Louisiana. ...Synopsis... A progressing short-wave trough initially forecast over the Middle Missouri Valley area is expected to move quickly northeastward toward/across the Great Lakes region through the first half of the period, and then into Ontario/Quebec overnight. At the surface, an associated cold front will move eastward across the Great Lakes and Ohio Valley areas, while moving more slowly southeastward across the Lower Mississippi Valley and southern Plains. By the end of the period, the boundary should extend from the Northeast to the Texas Coast. ...Southern Lower Michigan southwest to northeastern Texas/northern Louisiana... Showers and thunderstorms will be ongoing near and ahead of an advancing cold front -- which is initially forecast to lie from the southern Wisconsin vicinity southwestward to central Texas. With the associated upper system forecast to be ejecting quickly northeastward into/across the Upper Great Lakes region, decreasing ascent and weakening flow aloft is expected with time from roughly the Ohio Valley southward. Meanwhile, weak instability north of the Ohio Valley will be an overall limiting factor, despite more favorable kinematics. Overall, it appears that Level 1/MRGL risk remains appropriate, to cover the potential for a few stronger storms/line segments to produce strong/gusty winds that may locally reach severe levels. Risk should be greatest during the morning and afternoon hours, after which decreasing convective intensity and attendant severe potential is expected. ..Goss.. 10/30/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1136 AM CDT Wed Oct 30 2024 Valid 301700Z - 311200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF TEXAS/OKLAHOMA PANHANDLES INTO FAR NORTHWEST OKLAHOMA... Minor modifications were made to the elevated area in Kansas based on the current frontal position and expected surface low track this afternoon. The forecast is otherwise on track. See the previous discussion for additional details. ..Wendt.. 10/30/2024 .PREV DISCUSSION... /ISSUED 0203 AM CDT Wed Oct 30 2024/ ...Synopsis... A strong upper trough will intensify further as it ejects eastward over the central US today and tonight. Strong mid-level flow will accompany the trough, deepening a lee low over parts of CO/KS. The low will move northeast along a cold front across KS and OK, drawing an unusually moist air mass northward across the eastern Plains. To the west, dry and breezy conditions are likely over parts of TX and western OK, as well as the Midwest and Great Lakes. Elevated to critical fire-weather conditions are possible. ...Southern Plains... As the upper trough ejects eastward a 70-80 kt mid-level jet will round the base of the trough over the southern and central High Plains. West of a lee low and intensifying dryline, downslope winds of 25-35 mph are likely across much of the eastern Panhandle and western OK. Aided by mid-level subsidence and unusually warm temperatures in the mid to upper 80s F, afternoon RH values of 8-15% are expected through peak heating. The overlap of several hours of hot, dry and windy conditions over very dry fuels lends higher confidence in sustained critical fire-weather conditions this afternoon. Additionally, the cold front trailing the low will pass over the High Plains later this evening. A notable wind shift to north/northwesterly is expected after 00z. Strong winds could continue into the overnight hours exacerbating fire concerns despite increasing RH. ...Great Lakes... Dry and windy conditions are possible ahead of the deepening trough over parts of the Great Lakes and Midwest today. While RH values should steadily increase as moisture advects northward, sustained southerly winds near 15-20 mph will overlap with extremely dry fuels. While clouds and the increasing moisture should limit marginal RH, a few hours of locally elevated fire-weather conditions are possible this afternoon given the strong winds and unusually dry fuels. ...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 1130 AM CDT Wed Oct 30 2024 Valid 301630Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTHERN OKLAHOMA INTO CENTRAL/EASTERN KANSAS AND WESTERN MISSOURI... ...SUMMARY... Severe thunderstorms capable of producing scattered large hail, numerous damaging wind gusts, and a few tornadoes are expected today into tonight across the middle Missouri Valley and central/southern Plains, including parts of eastern Kansas/Oklahoma into Missouri and vicinity. ...Southern/Central Plains into the Mid Missouri Valley... The lead portion of an upper trough centered over the Rockies and Four Corners will eject northeastward over the central Plains today. A related surface low will likewise develop northeastward along a cold front from the southern High Plains to IA by this evening. A dryline extending southward from this low will mix eastward across western OK and west TX through late this afternoon before stalling. Robust low-level warm/moist advection will continue today across the southern/central Plains along and south/east of the cold front and dryline. Generally elevated thunderstorms have developed this morning across parts of central KS, as large-scale ascent preceding the ejecting upper trough has begun to overspread the central Plains. This activity should tend to remain just to the cool side of the front through the early afternoon. But, this convection may pose some threat for severe hail given sufficient MUCAPE with steepening mid-level lapse rates in the presence of strong deep-layer shear. There is also some chance it eventually becomes surface based later this afternoon across northeast KS. Otherwise, continued filtered daytime heating of the moistening warm sector should support around 500-1500 J/kg of MLCAPE by late afternoon from southern IA into eastern KS/western MO, and locally stronger to around 2000 J/kg in north-central OK. Current expectations are for surface-based thunderstorms to initiate by 20-22Z across central/eastern KS and north-central/northwest OK, in close proximity to the surface low and front/dryline intersection. Rather strong (50-80 kt) southwesterly mid-level flow will overlie this region this afternoon/evening, along with enhanced south-southwesterly flow in the 850-700 mb layer. Related deep-layer shear around 45-60 kt will easily support supercells and associated threat for scattered hail initially. Isolated very large hail may occur from south-central KS into north-central OK with any sustained supercell given the rather favorable overlap of moderate instability with steepened mid-level lapse rates and strong deep-layer shear. With time this evening, upscale growth into a QLCS with greater threat for severe/damaging winds is anticipated. This severe/damaging wind threat should continue tonight as the line spreads eastward across IA/MO, before eventually becoming more isolated/diminishing with eastward extent into the mid MS Valley. The tornado potential should also increase late this afternoon and evening, as a southerly low-level jet and related 0-1 km SRH strengthens rapidly through 23-04Z. The potential for sustained supercells in central/eastern KS and north-central OK remains somewhat unclear, but any semi-discrete activity will pose a threat for tornadoes, a couple of which could be strong given the favorable low-level shear and hodograph curvature. Embedded mesovorticies within the QLCS will also be possible. Based on latest guidance and observational trends, severe probabilities have been expanded westward some across KS/OK, especially in the vicinity of the expected front/dryline intersection. The Enhanced Risk has also been expanded slightly eastward in western MO to account for scattered to numerous severe wind gusts with the QLCS this evening. Convective initiation may be delayed until around 00Z or later across central/eastern OK. But, potential for discrete supercells may be a bit better across this region given the dryline as the initiating boundary, and somewhat less large-scale ascent with southward extent away from the cold front. Any convection that can develop and be sustained will likely be supercellular for at least a couple of hours this evening, before upscale growth eventually occurs along the cold front. A threat for large hail and tornadoes will exist with any supercell, before the damaging wind threat increases as the convective mode becomes more linear. ...Southeast Texas... There is some potential that a few stronger/potentially rotating thunderstorms could materialize today across the region within a very moist and confluent low-level flow regime. This would be as low-level lapse rates diurnally steepen coincident with a moderate degree of low-level hodograph length and curvature. Modest-strength winds above 2km AGL should limit the sustainability and intensity for any showers/thunderstorms that may exhibit rotating characteristics, and the overall severe potential should tend to remain limited. ..Gleason/Moore.. 10/30/2024 Read more

No watches are valid as of Wed Oct 30 15:31:02 UTC 2024.

No Mesoscale Discussions are in effect as of Wed Oct 30 15:31:02 UTC 2024.

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 AM CDT Wed Oct 30 2024 Valid 301300Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS EASTERN KANSAS...NORTHEAST OKLAHOMA...AND NORTHWEST MISSOURI... ...SUMMARY... Severe thunderstorms capable of producing large hail, damaging wind gusts, and a few tornadoes, are expected today into tonight across the middle Missouri Valley and central/southern Plains, including parts of eastern Kansas and Oklahoma into Missouri. ...Lower Missouri Valley/South-Central Plains... A relatively active severe-weather day is expected regionally, especially late this afternoon into evening, including some southern Plains areas in which there hasn't been severe-weather potential in over a month. The lead portion of an upper-level trough centered over the central/southern Rockies this morning will eject northeastward over the central Plains toward broader parts of the Upper Midwest and Corn Belt. A surface wave will evolve across the eastern Texas Panhandle/northwest Oklahoma vicinity. From this low, an east/southeastward-moving cold front will extend across Kansas into Iowa/Minnesota and eventually Wisconsin/western Missouri by this evening, with this front overtaking a dryline across the southern High Plains. Some severe-weather potential may increase as early as late morning into midday near the cold front across central Kansas into southeast Nebraska and Iowa, with a likely increase in surface-rooted convection and greater severe potential by mid/late afternoon as the front approaches east-central/northeast Kansas and northwest Missouri/southern Iowa. Pre-convective MLCAPE values should reach 500-1250 J/kg within this corridor, with very strong deep-layer southwesterly winds supporting 40-50 kt effective shear and fast east-northeastward storm motions, which will largely parallel the front and its east-southeastward motion. Some severe hail will be possible during the day, but damaging winds and some tornado potential will be more prevalent into late afternoon and evening as a QLCS evolves with embedded bowing segments and potential mesovortices. Farther south, in closer proximity to the surface wave, somewhat more discrete thunderstorm development is expected across south-central/east-central Kansas including the I-35/135 corridors and north-central Oklahoma, with prospects for even more isolated initial supercellular development by around sunset southward into central/southern Oklahoma and North Texas. Surface temperatures in the upper 70s F, combined with mid 60s F dewpoints, will contribute to 1500-2000 J/kg MLCAPE by peak heating. Storms that develop/mature in this environment will likely be supercells in the presence of 45+ effective shear, highlighted by a dramatic strengthening (50-65 kt) of 2-3 km AGL (surface-700 mb) southwesterly winds toward/after sunset. Storm mergers will result in squall line development over time, with a longer duration of more discrete development with southward extent across Oklahoma. A few tornadoes are plausible regionally, and a strong tornado or two could occur, particularly within a couple of hours of sunset. The severe threat should transition to more of a damaging wind threat as the squall line matures, although line-embedded QLCS tornadoes will remain possible this evening, and possibly overnight. ...Southeast Texas... There is some potential that a few stronger/potentially rotating storms could materialize today across the region within a very moist and confluent low-level flow regime. This would be as low-level lapse rates diurnally steepen coincident with a moderate degree of low-level hodograph length and curvature. Modest-strength winds above 2km AGL should limit the sustainability and intensity for any showers/thunderstorms that may exhibit rotating characteristics, and the overall severe potential should remain limited. ..Guyer/Leitman.. 10/30/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0303 AM CDT Wed Oct 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... ...Saturday/Day 4 to Monday/Day 6... An upper-level trough is forecast to move into the Desert Southwest on Saturday, as southwesterly mid-level flow remains over the Rockies and Great Plains. A moist airmass will be in place over much of the southern and central Plains. Along the western edge of the moist airmass, moderate instability is forecast to develop from eastern New Mexico into west Texas. Thunderstorms that develop along and near this instability axis will have a chance to be severe. Supercells could produce large hail and isolated severe wind gusts. On Sunday, low-level moisture advection is expected to continue over much of the Great Plains, as the upper-level trough moves across the Desert Southwest. Model forecasts are in reasonably good agreement, with an axis of moderate instability developing Sunday afternoon from northwest Texas into western and central Oklahoma northward into Kansas. Moderate deep-layer shear and steep mid-level lapse rates should support supercell development, with a potential for isolated large hail and wind damage. The threat should persist into the evening as scattered severe storms move eastward across the southern and central Plains. On Monday, the upper-level trough is forecast to move through the southern High Plains, as an 80 to 100 knot mid-level jet ejects northeastward into the southern and central Plains. Thunderstorms are expected to develop along a corridor of weak instability from central and north Texas northeastward into the Ozarks. Moderate deep-layer shear near the instability axis should support a severe threat during the afternoon and evening, with damaging wind gusts and isolated large hail as the primary threats. At this time, the timing of the ejecting mid-level jet, and magnitude of instability remain too uncertain to issue a threat area. ...Tuesday/Day 7 and Wednesday/Day 8... The upper-level trough is forecast to move quickly northeastward into the Great Lakes region on Tuesday, as mid-level flow remains southwesterly across the lower to mid Mississippi Valley. Isolated to scattered thunderstorms are expected to form Tuesday afternoon ahead of a cold front from the lower to mid Mississippi Valley north-northeastward into the lower Ohio Valley. On Wednesday, the front is forecast to move southeastward into the Ohio and Tennessee Valleys, suggesting the potential for isolated severe thunderstorms would be greatest from Kentucky southwestward into western Tennessee and northern Mississippi. However, spatial and magnitude uncertainty are substantial at this range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0303 AM CDT Wed Oct 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... ...Saturday/Day 4 to Monday/Day 6... An upper-level trough is forecast to move into the Desert Southwest on Saturday, as southwesterly mid-level flow remains over the Rockies and Great Plains. A moist airmass will be in place over much of the southern and central Plains. Along the western edge of the moist airmass, moderate instability is forecast to develop from eastern New Mexico into west Texas. Thunderstorms that develop along and near this instability axis will have a chance to be severe. Supercells could produce large hail and isolated severe wind gusts. On Sunday, low-level moisture advection is expected to continue over much of the Great Plains, as the upper-level trough moves across the Desert Southwest. Model forecasts are in reasonably good agreement, with an axis of moderate instability developing Sunday afternoon from northwest Texas into western and central Oklahoma northward into Kansas. Moderate deep-layer shear and steep mid-level lapse rates should support supercell development, with a potential for isolated large hail and wind damage. The threat should persist into the evening as scattered severe storms move eastward across the southern and central Plains. On Monday, the upper-level trough is forecast to move through the southern High Plains, as an 80 to 100 knot mid-level jet ejects northeastward into the southern and central Plains. Thunderstorms are expected to develop along a corridor of weak instability from central and north Texas northeastward into the Ozarks. Moderate deep-layer shear near the instability axis should support a severe threat during the afternoon and evening, with damaging wind gusts and isolated large hail as the primary threats. At this time, the timing of the ejecting mid-level jet, and magnitude of instability remain too uncertain to issue a threat area. ...Tuesday/Day 7 and Wednesday/Day 8... The upper-level trough is forecast to move quickly northeastward into the Great Lakes region on Tuesday, as mid-level flow remains southwesterly across the lower to mid Mississippi Valley. Isolated to scattered thunderstorms are expected to form Tuesday afternoon ahead of a cold front from the lower to mid Mississippi Valley north-northeastward into the lower Ohio Valley. On Wednesday, the front is forecast to move southeastward into the Ohio and Tennessee Valleys, suggesting the potential for isolated severe thunderstorms would be greatest from Kentucky southwestward into western Tennessee and northern Mississippi. However, spatial and magnitude uncertainty are substantial at this range. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0223 AM CDT Wed Oct 30 2024 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Marginally severe thunderstorms, associated with isolated large hail and a few severe wind gusts, will be possible Friday night in parts of the southern High Plains. ...Southern High Plains... Southwesterly mid-level flow will be in place across the Rockies and Great Plains on Friday, as a trough moves inland across the West Coast. Moisture advection will take place over the southern and central Plains, with surface dewpoints likely reaching the 60s F across much of Texas. The strongest instability is forecast by mid to late evening from far West Texas into eastern New Mexico, where scattered thunderstorms appear likely to develop. Additional convection is expected further to the east across west-central Texas. During the overnight period, thunderstorm coverage is forecast to expand northeastward into parts of the Texas Panhandle and northwest Texas. Forecast soundings from far West Texas into the Texas Panhandle Friday evening and overnight have MLCAPE reaching the 1000 to 1500 J/kg range. 0-6 km shear is forecast to be in the 30 to 35 knot range, with 700-500 mb lapse rates around 6.5 C/km. This environment would be sufficient for supercells with large hail. Marginally severe wind gusts will also be possible. The severe threat could persist to late in the period. ..Broyles.. 10/30/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0204 AM CDT Wed Oct 30 2024 Valid 311200Z - 011200Z ...NO CRITICAL AREAS... ...Synopsis... As the upper trough continues eastward, the attendant surface cyclone and cold front will move through the central US with thunderstorms and widespread precipitation ahead of it. Behind the front, high pressure and a cooler air mass will quickly develop over the Rockies and High Plains. Mid-level flow will slacken as the pattern evolves towards broad zonal flow and weak Pacific troughing. This should reduce the coverage of strong winds and low RH over much of the CONUS Thursday. One exception to this may be across portions of the Southwest. Here, mid-level flow will remain somewhat stronger, but the strongest winds are expected to overlap with only modestly low RH and relatively poor fuels given recent precipitation. Thus, critical fire-weather conditions appear unlikely. ..Lyons.. 10/30/2024 ...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 0203 AM CDT Wed Oct 30 2024 Valid 301200Z - 311200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN PLAINS... ...Synopsis... A strong upper trough will intensify further as it ejects eastward over the central US today and tonight. Strong mid-level flow will accompany the trough, deepening a lee low over parts of CO/KS. The low will move northeast along a cold front across KS and OK, drawing an unusually moist air mass northward across the eastern Plains. To the west, dry and breezy conditions are likely over parts of TX and western OK, as well as the Midwest and Great Lakes. Elevated to critical fire-weather conditions are possible. ...Southern Plains... As the upper trough ejects eastward a 70-80 kt mid-level jet will round the base of the trough over the southern and central High Plains. West of a lee low and intensifying dryline, downslope winds of 25-35 mph are likely across much of the eastern Panhandle and western OK. Aided by mid-level subsidence and unusually warm temperatures in the mid to upper 80s F, afternoon RH values of 8-15% are expected through peak heating. The overlap of several hours of hot, dry and windy conditions over very dry fuels lends higher confidence in sustained critical fire-weather conditions this afternoon. Additionally, the cold front trailing the low will pass over the High Plains later this evening. A notable wind shift to north/northwesterly is expected after 00z. Strong winds could continue into the overnight hours exacerbating fire concerns despite increasing RH. ...Great Lakes... Dry and windy conditions are possible ahead of the deepening trough over parts of the Great Lakes and Midwest today. While RH values should steadily increase as moisture advects northward, sustained southerly winds near 15-20 mph will overlap with extremely dry fuels. While clouds and the increasing moisture should limit marginal RH, a few hours of locally elevated fire-weather conditions are possible this afternoon given the strong winds and unusually dry fuels. ..Lyons.. 10/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0115 AM CDT Wed Oct 30 2024 Valid 301200Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF EASTERN KANSAS INTO FAR NORTHEASTERN OKLAHOMA AND NORTHWESTERN MISSOURI... CORRECTED FOR NDFD GRAPHIC ...SUMMARY... Strong/severe thunderstorms, capable of producing large hail, damaging wind gusts, and a few tornadoes, are expected today into early tonight, particularly from the middle Missouri Valley area into the southern Plains. ...Synopsis... A pronounced mid-level trough will traverse the Plains and become negatively tilted as it impinges on the Upper MS Valley today. Surface lee-troughing will remain in place across the Plains, resulting in the northward transport of an appreciably moist low-level airmass. A surface low will develop along the KS/OK border this afternoon and track toward the MS Valley this evening. A cold front will be draped across the MS Valley into KS while a dryline, extending from the low, is poised to sweep eastward across OK and northern TX through the day. Deep-layer ascent along and ahead of the cold front and dryline will support at least scattered thunderstorm initiation by late afternoon across the Plains. These storms will progress eastward amid a buoyant and highly sheared airmass. Severe storms are likely ahead of the cold front and dryline, with all hazards possible. ...Upper MS Valley into the southern Plains... Thunderstorms are expected to first initiate along the cold front over northern KS into western IA by mid to late afternoon as stronger upper-level support from the impinging mid-level trough overspreads the terminus of a 50+ kt southerly low-level jet. 7+ C/km mid-level lapse rates, overspreading rich low-level moisture (including mid-60s F surface dewpoints), should yield at least 1500 J/kg SBCAPE. Strong southwesterly 500 mb flow overspreading the low-level jet will contribute to 50+ kts of effective bulk shear, but with vectors aligned roughly parallel with the front. Initial semi-discrete storm modes, capable of mainly severe wind/hail, will quickly merge to form a QLCS with embedded bowing segments and perhaps a few mesovortices. This initial band of storms should approach the MS Valley region by sunset, accompanied by mainly damaging gusts and perhaps an isolated tornado threat. Farther south into central KS/northern OK, more discrete thunderstorm development is expected by early evening. Surface temperatures in the upper 70s F, combined with mid to perhaps upper 60s F dewpoints, will contribute to 1500-2000 J/kg MLCAPE just before sunset. Storms that can mature in this environment may benefit from over 50 kts of effective bulk shear, as well as an increase in low-level shear upon approaching the western periphery of the low-level jet. Forecast soundings depict overall curved low-level hodographs with mid-level elongation and 250-350 m2/s2 effective SRH. As such, supercells should be the initial storm mode before storm mergers result in squall line development. While many forecast soundings depict a weakness in the 800-600 mb layer, the overall strength of the low-level shear suggests at least a few tornadoes are possible, and a strong tornado or two may occur, mainly after dark. The severe threat may transition to more of a damaging gust threat after the squall line forms, though line-embedded QLCS tornadoes remain possible. ..Squitieri/Lyons.. 10/30/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1254 AM CDT Wed Oct 30 2024 Valid 311200Z - 011200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER TO MID MISSISSIPPI VALLEY...AND LOWER OHIO VALLEY... ...SUMMARY... Thunderstorms, associated with isolated severe wind gusts, will be possible Thursday afternoon along a narrow corridor from the Sabine River Valley north-northeastward into far southern Lower Michigan. ...Sabine River Valley/Lower to Mid Mississippi Valley/Lower Ohio Valley/Southern Great Lakes... A negatively-tilted upper-level trough, and an associated 70 to 80 knot mid-level speed max, will move northeastward into the Great Lakes on Thursday. At the surface, a cold front will advance eastward into the Ark-La-Tex and mid Mississippi Valley. Ahead of the front, surface dewpoints in the 60s F will contribute to weak destabilization in most areas by midday. Convection is expected to initiate along and ahead the front during the late morning as surface temperatures warm. Thunderstorms should gradually increase in coverage in the afternoon, moving eastward across the lower to mid Mississippi Valley, and lower Ohio Valley. Model solutions appear to present two scenarios. The first solution, which is depicted by the NAM, initiates convection near the front around midday from east-central Texas north-northeastward into the mid Mississippi Valley, with a second north-to-south band of storms developing much further east in the lower Mississippi Valley. The second solution, which is depicted by the ECMWF, focuses most of the convection further east near the center of the low-level moisture corridor in the lower to mid Mississippi Valley. Strong outflow from the previous night's convection is forecast to surge southeastward across much of central and east Texas Thursday morning, which could favor the second scenario, with an effective frontal boundary much further east. The severe threat should be concentrated along and near the axis of the strongest low-level flow, which is forecast to be in the lower to mid Mississippi Valley, and lower Ohio Valley. Forecast soundings near the moist axis in the afternoon have MLCAPE peaking from around 500 J/kg in the lower Ohio Valley to 1500 J/kg in the lower Mississippi Valley. Moderate deep-layer shear is forecast along much of the moist axis, where low-level lapse rates could peak near 7 C/km in areas that heat up the most. This environment will likely support an isolated wind-damage threat during the afternoon, with the stronger and more organized multicells. A marginal tornado threat may also develop, mainly from western Tennessee south-southwestward into northern Louisiana, where the combination of instability and shear is forecast to be maximized, in conjunction with steep low-level lapse rates. ..Broyles.. 10/30/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1254 AM CDT Wed Oct 30 2024 Valid 311200Z - 011200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER TO MID MISSISSIPPI VALLEY...AND LOWER OHIO VALLEY... ...SUMMARY... Thunderstorms, associated with isolated severe wind gusts, will be possible Thursday afternoon along a narrow corridor from the Sabine River Valley north-northeastward into far southern Lower Michigan. ...Sabine River Valley/Lower to Mid Mississippi Valley/Lower Ohio Valley/Southern Great Lakes... A negatively-tilted upper-level trough, and an associated 70 to 80 knot mid-level speed max, will move northeastward into the Great Lakes on Thursday. At the surface, a cold front will advance eastward into the Ark-La-Tex and mid Mississippi Valley. Ahead of the front, surface dewpoints in the 60s F will contribute to weak destabilization in most areas by midday. Convection is expected to initiate along and ahead the front during the late morning as surface temperatures warm. Thunderstorms should gradually increase in coverage in the afternoon, moving eastward across the lower to mid Mississippi Valley, and lower Ohio Valley. Model solutions appear to present two scenarios. The first solution, which is depicted by the NAM, initiates convection near the front around midday from east-central Texas north-northeastward into the mid Mississippi Valley, with a second north-to-south band of storms developing much further east in the lower Mississippi Valley. The second solution, which is depicted by the ECMWF, focuses most of the convection further east near the center of the low-level moisture corridor in the lower to mid Mississippi Valley. Strong outflow from the previous night's convection is forecast to surge southeastward across much of central and east Texas Thursday morning, which could favor the second scenario, with an effective frontal boundary much further east. The severe threat should be concentrated along and near the axis of the strongest low-level flow, which is forecast to be in the lower to mid Mississippi Valley, and lower Ohio Valley. Forecast soundings near the moist axis in the afternoon have MLCAPE peaking from around 500 J/kg in the lower Ohio Valley to 1500 J/kg in the lower Mississippi Valley. Moderate deep-layer shear is forecast along much of the moist axis, where low-level lapse rates could peak near 7 C/km in areas that heat up the most. This environment will likely support an isolated wind-damage threat during the afternoon, with the stronger and more organized multicells. A marginal tornado threat may also develop, mainly from western Tennessee south-southwestward into northern Louisiana, where the combination of instability and shear is forecast to be maximized, in conjunction with steep low-level lapse rates. ..Broyles.. 10/30/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1252 AM CDT Wed Oct 30 2024 Valid 301200Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF EASTERN KANSAS INTO FAR NORTHEASTERN OKLAHOMA AND NORTHWESTERN MISSOURI... ...SUMMARY... Strong/severe thunderstorms, capable of producing large hail, damaging wind gusts, and a few tornadoes, are expected today into early tonight, particularly from the middle Missouri Valley area into the southern Plains. ...Synopsis... A pronounced mid-level trough will traverse the Plains and become negatively tilted as it impinges on the Upper MS Valley today. Surface lee-troughing will remain in place across the Plains, resulting in the northward transport of an appreciably moist low-level airmass. A surface low will develop along the KS/OK border this afternoon and track toward the MS Valley this evening. A cold front will be draped across the MS Valley into KS while a dryline, extending from the low, is poised to sweep eastward across OK and northern TX through the day. Deep-layer ascent along and ahead of the cold front and dryline will support at least scattered thunderstorm initiation by late afternoon across the Plains. These storms will progress eastward amid a buoyant and highly sheared airmass. Severe storms are likely ahead of the cold front and dryline, with all hazards possible. ...Upper MS Valley into the southern Plains... Thunderstorms are expected to first initiate along the cold front over northern KS into western IA by mid to late afternoon as stronger upper-level support from the impinging mid-level trough overspreads the terminus of a 50+ kt southerly low-level jet. 7+ C/km mid-level lapse rates, overspreading rich low-level moisture (including mid-60s F surface dewpoints), should yield at least 1500 J/kg SBCAPE. Strong southwesterly 500 mb flow overspreading the low-level jet will contribute to 50+ kts of effective bulk shear, but with vectors aligned roughly parallel with the front. Initial semi-discrete storm modes, capable of mainly severe wind/hail, will quickly merge to form a QLCS with embedded bowing segments and perhaps a few mesovortices. This initial band of storms should approach the MS Valley region by sunset, accompanied by mainly damaging gusts and perhaps an isolated tornado threat. Farther south into central KS/northern OK, more discrete thunderstorm development is expected by early evening. Surface temperatures in the upper 70s F, combined with mid to perhaps upper 60s F dewpoints, will contribute to 1500-2000 J/kg MLCAPE just before sunset. Storms that can mature in this environment may benefit from over 50 kts of effective bulk shear, as well as an increase in low-level shear upon approaching the western periphery of the low-level jet. Forecast soundings depict overall curved low-level hodographs with mid-level elongation and 250-350 m2/s2 effective SRH. As such, supercells should be the initial storm mode before storm mergers result in squall line development. While many forecast soundings depict a weakness in the 800-600 mb layer, the overall strength of the low-level shear suggests at least a few tornadoes are possible, and a strong tornado or two may occur, mainly after dark. The severe threat may transition to more of a damaging gust threat after the squall line forms, though line-embedded QLCS tornadoes remain possible. ..Squitieri/Lyons.. 10/30/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0746 PM CDT Tue Oct 29 2024 Valid 300100Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm development may occur early Wednesday morning across parts of the southern/central Plains into the Upper Mississippi Valley. ...Synopsis... A pronounced mid-level trough over the Rockies will continue to progress eastward toward the Plains tonight. In advance of the mid-level trough, broad surface lee troughing is taking place across the central U.S., where an intense (50-60kt) low-level jet is expected to develop, leading to ample northward low-level warm-air/moisture advection through the remainder of the period. Given the gradual approach of favorable upper-level support, thunderstorm initiation has become more questionable before 12Z. Nonetheless, thunder probabilities have been maintained in the event that thunderstorms can develop atop a moist boundary layer. A couple of lightning flashes also cannot be ruled out over portions of the TX Gulf Coast given onshore advection of rich low-level moisture. ..Squitieri.. 10/30/2024 Read more

No watches are valid as of Tue Oct 29 22:45:01 UTC 2024.

No Mesoscale Discussions are in effect as of Tue Oct 29 22:45:01 UTC 2024.