SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Fri Oct 25 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential is low today. ...Discussion... Deamplification of the lower MO Valley short-wave trough is expected to continue through the day1 period as this feature progresses across the OH Valley into the northern middle Atlantic after 26/00z. In response to this short wave, a weak surface low will track across the mid MS Valley early, then lose its identity as a pronounced surface front advances southeast. This boundary will serve as one focus for potential convective development, along with warm advection. Modest boundary-layer heating is expected to result in weak buoyancy ahead of the front; although, weak instability will also be noted within the warm advection zone. In both cases, it appears some risk for lightning will be noted with the deeper updrafts. Forecast soundings suggest parcels will exceed levels necessary for lightning discharge but the threat of severe appears low, namely due to weak instability. ..Darrow/Lyons.. 10/25/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 PM CDT Thu Oct 24 2024 Valid 250100Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST KANSAS INTO IOWA... ...SUMMARY... Isolated large hail and strong wind gusts remain possible from eastern Kansas into northern Missouri and parts of Iowa this evening into early tonight. ...01z Update... Leading edge of large-scale forcing is spreading across central IA, coincident with focused low-level warm advection along the nose of the LLJ. Scattered strong thunderstorms have evolved within this corridor, including several clusters. A few marginally severe hail reports were noted earlier across northern IA, but overall MESH cores are not that significant as the magnitude of instability is not that great, despite the steep mid-level lapse rates. Robust updrafts extend southwest along the cold front across northeast KS. This activity has developed within a more buoyant air mass characterized by near-dry adiabatic lapse rates in the 0-3km layer, and MLCAPE around 900 J/kg, per 00z sounding from TOP. Large hail (around 1 inch) should be the primary concern with storms as they propagate across eastern KS into northwest MO, along with some risk for gusty winds. Nocturnal cooling should lessen instability later this evening and this will likely lead to weaker updrafts and small hail and weaker downdrafts. ..Darrow.. 10/25/2024 Read more

MD 2159 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR MUCH OF IOWA...INTO PORTIONS OF FAR NORTHWESTERN ILLINOIS AND SOUTHERN MINNESOTA.
Mesoscale Discussion 2159 NWS Storm Prediction Center Norman OK 0522 PM CDT Thu Oct 24 2024 Areas affected...Much of Iowa... into portions of far northwestern Illinois and southern Minnesota. Concerning...Severe potential...Watch unlikely Valid 242222Z - 250045Z Probability of Watch Issuance...20 percent SUMMARY...Multiple areas of scattered thunderstorms ongoing within a broad warm-air advection regime may pose a threat for occasional severe hail through the evening and overnight hours. A WW is unlikely, though conditions are being monitored. DISCUSSION...As of 2210 UTC, regional radar and satellite imagery showed multiple clusters of scattered to numerous thunderstorms ongoing over IA, northwest IL, and southern MN. Located ahead of a shortwave trough over the central Plains and north of a surface warm front near the Missouri River, these storms are ongoing in a relatively strong low-level warm-air advection regime. Broad isentropic ascent and the arrival of a cold front should continue to support sufficient lift from scattered to numerous thunderstorms this evening. Despite very poor low-level dewpoints and lapse rates, several elevated clusters have emerged over parts of IA, MN and IL with occasional reports of hail and gusty winds with the more robust convection. MUCAPE around 1000 J/kg, overlapping with cool mid-level temperatures and 35-45 kt of effective shear will support a mixed mode of elevated supercells and linear clusters capable of isolated severe hail and perhaps a strong wind gust through this evening. Additional storm development appears likely as a robust 30-40 kt low-level jet and cold front arrives later this evening. Numerous elevated storms should spread east into eastern IA and NW IL with the potential for a couple of more organized cells to produce isolated hail and gusty winds. Given the relatively limited coverage of organized severe storms and limited buoyancy with eastward extent, a watch is not currently anticipated. ..Lyons/Hart.. 10/24/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DVN...ARX...MPX...DMX...FSD...OAX... LAT...LON 42759624 43689545 44259434 44279424 43989227 43779182 43369132 42769104 42029087 41279098 40969139 40859212 40939340 40969434 41559593 42759624 Read more

No watches are valid as of Thu Oct 24 23:01:02 UTC 2024.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0454 PM CDT Thu Oct 24 2024 Valid 261200Z - 011200Z An upper-level trough will break down an amplified ridge over the West this weekend. Upper level ridging will shift east over the central US, with deep upper level troughing over the Northeast through early next week. Upper-level ridging will amplify over the eastern US as the trough deepens over the West and into the central US mid-next week, with well above normal temperatures preceding the upper-level trough. ...Day 4/Sunday - Day 6/Tuesday... Dry/breezy conditions will develop ahead of a Pacific cold front in portions of the central/northern High Plains and Great Basin Day 4/Sunday. Critical winds/RH are most likely across portions southeast Wyoming and western Nebraska, but this area may expand into northeast Colorado, southeast Montana, and the western Dakotas depending on the track/timing of the upper-level trough. Additionally, a 40% area was almost included for portions of eastern Nevada and western Utah, but there is too much uncertainty regarding critical winds/RH overlapping dry fuels. On Day 5/Monday, dry/windy conditions will overspread portions of the Southwest and southern/central Plains. Two 40% areas are delineated highlighting the corridors with the highest probabilities of critical winds/RH overlapping receptive fuels. Additionally, depending on the timing of the cold frontal passage, critical conditions may develop in northeast Colorado, southeast Wyoming, and western Nebraska. Dry/windy conditions are likely to continue on portions of the southern/central High Plains on Day 6/Tuesday, but too much forecast uncertainty exists to issue any areas at this time. Dry/breezy pre-frontal conditions may emerge in portions of the Great Lakes/Midwest amid well above normal temperatures on Day 5/Monday - Day 6/Tuesday. However, this is dependent on the moisture return ahead of the upper-level trough, which remains uncertain. ...Day 6/Tuesday - Day 8/Thursday... Gusty northerly and offshore winds are likely in portions of central/southern California Day 6/Tuesday and possibly into Day 8/Thursday. Uncertainty remains regarding the duration, magnitude, and spatial extent of this event, but areas may be necessary in subsequent outlooks. ..Nauslar.. 10/24/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0454 PM CDT Thu Oct 24 2024 Valid 261200Z - 011200Z An upper-level trough will break down an amplified ridge over the West this weekend. Upper level ridging will shift east over the central US, with deep upper level troughing over the Northeast through early next week. Upper-level ridging will amplify over the eastern US as the trough deepens over the West and into the central US mid-next week, with well above normal temperatures preceding the upper-level trough. ...Day 4/Sunday - Day 6/Tuesday... Dry/breezy conditions will develop ahead of a Pacific cold front in portions of the central/northern High Plains and Great Basin Day 4/Sunday. Critical winds/RH are most likely across portions southeast Wyoming and western Nebraska, but this area may expand into northeast Colorado, southeast Montana, and the western Dakotas depending on the track/timing of the upper-level trough. Additionally, a 40% area was almost included for portions of eastern Nevada and western Utah, but there is too much uncertainty regarding critical winds/RH overlapping dry fuels. On Day 5/Monday, dry/windy conditions will overspread portions of the Southwest and southern/central Plains. Two 40% areas are delineated highlighting the corridors with the highest probabilities of critical winds/RH overlapping receptive fuels. Additionally, depending on the timing of the cold frontal passage, critical conditions may develop in northeast Colorado, southeast Wyoming, and western Nebraska. Dry/windy conditions are likely to continue on portions of the southern/central High Plains on Day 6/Tuesday, but too much forecast uncertainty exists to issue any areas at this time. Dry/breezy pre-frontal conditions may emerge in portions of the Great Lakes/Midwest amid well above normal temperatures on Day 5/Monday - Day 6/Tuesday. However, this is dependent on the moisture return ahead of the upper-level trough, which remains uncertain. ...Day 6/Tuesday - Day 8/Thursday... Gusty northerly and offshore winds are likely in portions of central/southern California Day 6/Tuesday and possibly into Day 8/Thursday. Uncertainty remains regarding the duration, magnitude, and spatial extent of this event, but areas may be necessary in subsequent outlooks. ..Nauslar.. 10/24/2024 ...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 0246 PM CDT Thu Oct 24 2024 Valid 242000Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF EASTERN KANSAS INTO NORTHERN MISSOURI AND IOWA... ...SUMMARY... Isolated large hail (up to 1-1.75 inch diameter) and strong wind gusts (around 50-60 mph) will be possible from eastern Kansas into northern Missouri and parts of Iowa this evening into early tonight. ...20Z Update... ...Eastern Kansas into Missouri and Iowa... Recent surface analysis places the primary low over southeast SD, with a cold front extending southwestward from this low across central NE and into western KS. Additional surface cyclogenesis is still anticipated over central KS later this evening, at the intersection of the aforementioned cold front and a warm front that arcs from north-central KS eastward to MCI and even more southeastward through southwest MO. This warm front is expected to continue slowly progress northeastward, with warm and modest moist conditions advecting into eastern KS and adjacent far western MO. Thunderstorms are still expected as the cold front interacts with a modestly buoyant airmass across eastern KS and western MO. Some cellular activity is possible initially, with 35 to 45 kt of effective bulk shear supporting the potential for large hail (1 to 1.75" in diameter). Given the strong forcing along the front, any development should trend towards a linear mode quickly. The opportunity for severe will be limited by both the fast-moving front and narrow corridor of buoyancy, with severe coverage expected to remain isolated. A few isolated gusts from 50 to 60 mph are anticipated as well. Isolated hail also remains possible across southern IA, where warm-air advection should result in elevated thunderstorms amid cold mid-level temperatures and moderate vertical shear. In both of these areas, the overall severe coverage is still forecast to remain isolated, precluding the need to increase severe probabilities with this update. ..Mosier.. 10/24/2024 .PREV DISCUSSION... /ISSUED 1124 AM CDT Thu Oct 24 2024/ ...Eastern Kansas into Missouri and Iowa... A shortwave trough over WY/CO will continue eastward across the central Plains through this evening, eventually reaching the mid MS Valley by early Friday morning. Related cyclogenesis across the central High Plains will lead to a consolidated surface low over the mid MO Valley this evening, with a cold front extending southwestward from the low across KS. A warm front should also be located over northern MO. Shallow low-level moisture, characterized by generally upper 50s to low 60s dewpoints, will be present across the warm sector from eastern KS into MO by late this afternoon. With the late arrival of large-scale ascent associated with the shortwave trough, most guidance continues to show convective initiation occurring around 00Z, beginning in eastern KS and vicinity. Up to 750-1250 J/kg of MLCAPE should be present across this area, with robust daytime heating aiding in the development of steep low-level lapse rates. Initial development may be briefly supercellular, as 30-40 kt of deep-layer shear supports updraft organization. Severe hail up to 1-1.75 inches in diameter will be possible with this initial activity, before a quick mode transition to more linear structures occurs along the cold front through the evening. Isolated strong to severe gusts (around 50-60 mph) may occur so long as thunderstorms remain surface based, before convection tends to become elevated with eastward extent into MO later this evening. Isolated hail may also occur this evening into the early overnight hours across parts of IA and northern MO, along/north of the warm front in a low-level warm advection regime. Sufficient MUCAPE and deep-layer shear should be present for robust updrafts, although it remains unclear whether supercells will be able to maintained for more than an hour or two. Given continued uncertainty in the number and longevity of surface-based supercells across eastern KS into northwest MO this evening, have opted to maintain the Marginal Risk with this update. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Thu Oct 24 2024 Valid 242000Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF EASTERN KANSAS INTO NORTHERN MISSOURI AND IOWA... ...SUMMARY... Isolated large hail (up to 1-1.75 inch diameter) and strong wind gusts (around 50-60 mph) will be possible from eastern Kansas into northern Missouri and parts of Iowa this evening into early tonight. ...20Z Update... ...Eastern Kansas into Missouri and Iowa... Recent surface analysis places the primary low over southeast SD, with a cold front extending southwestward from this low across central NE and into western KS. Additional surface cyclogenesis is still anticipated over central KS later this evening, at the intersection of the aforementioned cold front and a warm front that arcs from north-central KS eastward to MCI and even more southeastward through southwest MO. This warm front is expected to continue slowly progress northeastward, with warm and modest moist conditions advecting into eastern KS and adjacent far western MO. Thunderstorms are still expected as the cold front interacts with a modestly buoyant airmass across eastern KS and western MO. Some cellular activity is possible initially, with 35 to 45 kt of effective bulk shear supporting the potential for large hail (1 to 1.75" in diameter). Given the strong forcing along the front, any development should trend towards a linear mode quickly. The opportunity for severe will be limited by both the fast-moving front and narrow corridor of buoyancy, with severe coverage expected to remain isolated. A few isolated gusts from 50 to 60 mph are anticipated as well. Isolated hail also remains possible across southern IA, where warm-air advection should result in elevated thunderstorms amid cold mid-level temperatures and moderate vertical shear. In both of these areas, the overall severe coverage is still forecast to remain isolated, precluding the need to increase severe probabilities with this update. ..Mosier.. 10/24/2024 .PREV DISCUSSION... /ISSUED 1124 AM CDT Thu Oct 24 2024/ ...Eastern Kansas into Missouri and Iowa... A shortwave trough over WY/CO will continue eastward across the central Plains through this evening, eventually reaching the mid MS Valley by early Friday morning. Related cyclogenesis across the central High Plains will lead to a consolidated surface low over the mid MO Valley this evening, with a cold front extending southwestward from the low across KS. A warm front should also be located over northern MO. Shallow low-level moisture, characterized by generally upper 50s to low 60s dewpoints, will be present across the warm sector from eastern KS into MO by late this afternoon. With the late arrival of large-scale ascent associated with the shortwave trough, most guidance continues to show convective initiation occurring around 00Z, beginning in eastern KS and vicinity. Up to 750-1250 J/kg of MLCAPE should be present across this area, with robust daytime heating aiding in the development of steep low-level lapse rates. Initial development may be briefly supercellular, as 30-40 kt of deep-layer shear supports updraft organization. Severe hail up to 1-1.75 inches in diameter will be possible with this initial activity, before a quick mode transition to more linear structures occurs along the cold front through the evening. Isolated strong to severe gusts (around 50-60 mph) may occur so long as thunderstorms remain surface based, before convection tends to become elevated with eastward extent into MO later this evening. Isolated hail may also occur this evening into the early overnight hours across parts of IA and northern MO, along/north of the warm front in a low-level warm advection regime. Sufficient MUCAPE and deep-layer shear should be present for robust updrafts, although it remains unclear whether supercells will be able to maintained for more than an hour or two. Given continued uncertainty in the number and longevity of surface-based supercells across eastern KS into northwest MO this evening, have opted to maintain the Marginal Risk with this update. Read more

No Mesoscale Discussions are in effect as of Thu Oct 24 19:51:02 UTC 2024.

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 PM CDT Thu Oct 24 2024 Valid 261200Z - 271200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast across the contiguous states on Saturday. ...Synopsis... Little thunderstorm activity is expected on Saturday across the CONUS, owing to a ridge in the west and a dry northwest flow regime across the East. This pattern will maintain high pressure over most of the US land mass, with little destabilization. Very weak instability may develop mainly offshore of the Pacific Northwest as an upper trough approaches into Sunday morning, and a flash or two cannot be ruled out just offshore. ..Jewell.. 10/24/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 PM CDT Thu Oct 24 2024 Valid 261200Z - 271200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast across the contiguous states on Saturday. ...Synopsis... Little thunderstorm activity is expected on Saturday across the CONUS, owing to a ridge in the west and a dry northwest flow regime across the East. This pattern will maintain high pressure over most of the US land mass, with little destabilization. Very weak instability may develop mainly offshore of the Pacific Northwest as an upper trough approaches into Sunday morning, and a flash or two cannot be ruled out just offshore. ..Jewell.. 10/24/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0154 PM CDT Thu Oct 24 2024 Valid 251200Z - 261200Z ...NO CRITICAL AREAS... Locally elevated conditions remain possible on portions of the southern/central Plains into the Midwest amid a dry/breezy post-frontal airmass. The forecast remains on track and please see the previous discussion for more details. ..Nauslar.. 10/24/2024 .PREV DISCUSSION... /ISSUED 0107 AM CDT Thu Oct 24 2024/ ...Synopsis... Large-scale critical fire weather concerns a not anticipated across the contiguous United States. A surface cold front will continue to push east through the central United States and into the Ohio Valley on Friday. In the wake of this front, gusty northerly winds will reinforce a dry airmass in place across the Plains. Cooler conditions behind the front will result in slightly higher relative humidity values than the day before, which should somewhat constrain the overall large-scale fire weather threat. ...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 0154 PM CDT Thu Oct 24 2024 Valid 251200Z - 261200Z ...NO CRITICAL AREAS... Locally elevated conditions remain possible on portions of the southern/central Plains into the Midwest amid a dry/breezy post-frontal airmass. The forecast remains on track and please see the previous discussion for more details. ..Nauslar.. 10/24/2024 .PREV DISCUSSION... /ISSUED 0107 AM CDT Thu Oct 24 2024/ ...Synopsis... Large-scale critical fire weather concerns a not anticipated across the contiguous United States. A surface cold front will continue to push east through the central United States and into the Ohio Valley on Friday. In the wake of this front, gusty northerly winds will reinforce a dry airmass in place across the Plains. Cooler conditions behind the front will result in slightly higher relative humidity values than the day before, which should somewhat constrain the overall large-scale fire weather threat. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1204 PM CDT Thu Oct 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... No severe thunderstorms are expected on Friday. ...Synopsis and Discussion... The stronger flow aloft will remain over the northern half of the CONUS and into CN with a flattening ridge over the western CONUS and a high over Baja CA. Cold air aloft beneath strong cyclonic flow will spread across the Great Lakes and into the Northeast as a large upper cyclone situates over Hudson Bay. At the surface, high pressure will exist across the Plains and over the East, providing generally dry and stable conditions. The exception will be a narrow/in between zone from the OH Valley into northern TX near a cold front. This zone will be characterized by 50s F dewpoints and generally weak instability. Ascent looks to be most favorable early in the day from southern MO into IL, IN, and western OH, and scattered elevated thunderstorms will be possible. ..Jewell.. 10/24/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 AM CDT Thu Oct 24 2024 Valid 241630Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF EASTERN KANSAS INTO NORTHERN MISSOURI AND IOWA... ...SUMMARY... Isolated large hail (up to 1-1.75 inch diameter) and strong wind gusts (around 50-60 mph) will be possible from eastern Kansas into northern Missouri and parts of Iowa this evening into early tonight. ...Eastern Kansas into Missouri and Iowa... A shortwave trough over WY/CO will continue eastward across the central Plains through this evening, eventually reaching the mid MS Valley by early Friday morning. Related cyclogenesis across the central High Plains will lead to a consolidated surface low over the mid MO Valley this evening, with a cold front extending southwestward from the low across KS. A warm front should also be located over northern MO. Shallow low-level moisture, characterized by generally upper 50s to low 60s dewpoints, will be present across the warm sector from eastern KS into MO by late this afternoon. With the late arrival of large-scale ascent associated with the shortwave trough, most guidance continues to show convective initiation occurring around 00Z, beginning in eastern KS and vicinity. Up to 750-1250 J/kg of MLCAPE should be present across this area, with robust daytime heating aiding in the development of steep low-level lapse rates. Initial development may be briefly supercellular, as 30-40 kt of deep-layer shear supports updraft organization. Severe hail up to 1-1.75 inches in diameter will be possible with this initial activity, before a quick mode transition to more linear structures occurs along the cold front through the evening. Isolated strong to severe gusts (around 50-60 mph) may occur so long as thunderstorms remain surface based, before convection tends to become elevated with eastward extent into MO later this evening. Isolated hail may also occur this evening into the early overnight hours across parts of IA and northern MO, along/north of the warm front in a low-level warm advection regime. Sufficient MUCAPE and deep-layer shear should be present for robust updrafts, although it remains unclear whether supercells will be able to maintained for more than an hour or two. Given continued uncertainty in the number and longevity of surface-based supercells across eastern KS into northwest MO this evening, have opted to maintain the Marginal Risk with this update. ..Gleason/Thornton.. 10/24/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 AM CDT Thu Oct 24 2024 Valid 241630Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF EASTERN KANSAS INTO NORTHERN MISSOURI AND IOWA... ...SUMMARY... Isolated large hail (up to 1-1.75 inch diameter) and strong wind gusts (around 50-60 mph) will be possible from eastern Kansas into northern Missouri and parts of Iowa this evening into early tonight. ...Eastern Kansas into Missouri and Iowa... A shortwave trough over WY/CO will continue eastward across the central Plains through this evening, eventually reaching the mid MS Valley by early Friday morning. Related cyclogenesis across the central High Plains will lead to a consolidated surface low over the mid MO Valley this evening, with a cold front extending southwestward from the low across KS. A warm front should also be located over northern MO. Shallow low-level moisture, characterized by generally upper 50s to low 60s dewpoints, will be present across the warm sector from eastern KS into MO by late this afternoon. With the late arrival of large-scale ascent associated with the shortwave trough, most guidance continues to show convective initiation occurring around 00Z, beginning in eastern KS and vicinity. Up to 750-1250 J/kg of MLCAPE should be present across this area, with robust daytime heating aiding in the development of steep low-level lapse rates. Initial development may be briefly supercellular, as 30-40 kt of deep-layer shear supports updraft organization. Severe hail up to 1-1.75 inches in diameter will be possible with this initial activity, before a quick mode transition to more linear structures occurs along the cold front through the evening. Isolated strong to severe gusts (around 50-60 mph) may occur so long as thunderstorms remain surface based, before convection tends to become elevated with eastward extent into MO later this evening. Isolated hail may also occur this evening into the early overnight hours across parts of IA and northern MO, along/north of the warm front in a low-level warm advection regime. Sufficient MUCAPE and deep-layer shear should be present for robust updrafts, although it remains unclear whether supercells will be able to maintained for more than an hour or two. Given continued uncertainty in the number and longevity of surface-based supercells across eastern KS into northwest MO this evening, have opted to maintain the Marginal Risk with this update. ..Gleason/Thornton.. 10/24/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Thu Oct 24 2024 Valid 241700Z - 251200Z An Elevated area was added for portions of northeast Colorado. RH values are already around or below 20% in this area with wind gusts of 15-40 mph. Showers are developing over the northern Front Range along the CO/WY border but the Elevated area is south of these showers where the greatest overlap of strong west-northwest winds, low RH, and dry fuels should materialize. Otherwise, the forecast remains on track and please see the previous discussion. ..Nauslar.. 10/24/2024 .PREV DISCUSSION... /ISSUED 0106 AM CDT Thu Oct 24 2024/ ...Synopsis... Elevated fire weather conditions will be likely across portions of the Southern Plains this afternoon within a relatively dry return flow regime. Elsewhere, locally elevated fire weather conditions may develop across portions of southern New England into the Mid-Atlantic region. ... Southern Plains ... A weak frontal boundary will weaken and dissipate in response to lee cyclogenesis. The result will be strong, gusty southerly surface winds in the presence of near-record high temperatures. Although model forecasts suggest relative humidity will only fall into the upper 20s to low 30s, the combination of ongoing drought and receptive fuels should more than compensate. Additionally, surface moisture appears to be rather shallow and may be susceptible to mixing out. If this happens, relative humidity may be considerably lower than forecast, resulting in an increase in potential for extreme fire behavior. ... Southern New England into the Mid-Atlantic Region ... Strong, gusty winds will develop ahead of a surface trough. Warm afternoon temperatures will allow minimum relative humidity to fall into the 30s and 40s -- locally lower. The result may be a couple of hours in the afternoon with locally elevated fire conditions. ...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 1122 AM CDT Thu Oct 24 2024 Valid 241700Z - 251200Z An Elevated area was added for portions of northeast Colorado. RH values are already around or below 20% in this area with wind gusts of 15-40 mph. Showers are developing over the northern Front Range along the CO/WY border but the Elevated area is south of these showers where the greatest overlap of strong west-northwest winds, low RH, and dry fuels should materialize. Otherwise, the forecast remains on track and please see the previous discussion. ..Nauslar.. 10/24/2024 .PREV DISCUSSION... /ISSUED 0106 AM CDT Thu Oct 24 2024/ ...Synopsis... Elevated fire weather conditions will be likely across portions of the Southern Plains this afternoon within a relatively dry return flow regime. Elsewhere, locally elevated fire weather conditions may develop across portions of southern New England into the Mid-Atlantic region. ... Southern Plains ... A weak frontal boundary will weaken and dissipate in response to lee cyclogenesis. The result will be strong, gusty southerly surface winds in the presence of near-record high temperatures. Although model forecasts suggest relative humidity will only fall into the upper 20s to low 30s, the combination of ongoing drought and receptive fuels should more than compensate. Additionally, surface moisture appears to be rather shallow and may be susceptible to mixing out. If this happens, relative humidity may be considerably lower than forecast, resulting in an increase in potential for extreme fire behavior. ... Southern New England into the Mid-Atlantic Region ... Strong, gusty winds will develop ahead of a surface trough. Warm afternoon temperatures will allow minimum relative humidity to fall into the 30s and 40s -- locally lower. The result may be a couple of hours in the afternoon with locally elevated fire conditions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0730 AM CDT Thu Oct 24 2024 Valid 241300Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO EARLY TONIGHT FROM EASTERN KS TO NORTHERN MO AND IA... ...SUMMARY... Isolated large hail (1-1.75 inch diameter) and isolated strong gusts (50-60 mph) will be possible from eastern Kansas into northern Missouri and much of Iowa this evening into early tonight. ...Eastern KS/northern MO/IA this evening into tonight... A midlevel shortwave trough over western WY this morning will progress to the central Plains this evening and the mid MS Valley by early Friday. Downstream from this midlevel trough, lee cyclogenesis is expected across the central High Plains this afternoon, which will aid in northward advection of a partially modified Gulf air mass (boundary-layer dewpoints of 55-60 F). Strong surface heating/mixing across KS/OK will result in a narrow surface warm sector with moderate buoyancy (MLCAPE near 1000 J/kg) by mid-late afternoon across eastern KS. The eastern extent of the surface warm sector will be demarcated by a warm front into western MO. Surface-based thunderstorm development will be possible by roughly 22-00z along a surface trough/cold front across eastern KS, with subsequent expansion of elevated convection farther northeast across northern MO/southern IA through early tonight in a zone of strengthening low-level warm advection. Isolated strong outflow gusts (50-60 mph) will be possible with the initial storms across eastern KS this evening in the zone of steeper low-level lapse rates. Steep midlevel lapse rates, moderate buoyancy, and sufficiently long/curved hodographs will support some potential for embedded supercells capable of producing isolated large hail (1-1.75 inch diameter) into early tonight. The area from eastern KS to northwest MO was considered for a SLGT risk upgrade, and this area will be monitored closely in later outlook updates. ..Thompson/Goss.. 10/24/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0730 AM CDT Thu Oct 24 2024 Valid 241300Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO EARLY TONIGHT FROM EASTERN KS TO NORTHERN MO AND IA... ...SUMMARY... Isolated large hail (1-1.75 inch diameter) and isolated strong gusts (50-60 mph) will be possible from eastern Kansas into northern Missouri and much of Iowa this evening into early tonight. ...Eastern KS/northern MO/IA this evening into tonight... A midlevel shortwave trough over western WY this morning will progress to the central Plains this evening and the mid MS Valley by early Friday. Downstream from this midlevel trough, lee cyclogenesis is expected across the central High Plains this afternoon, which will aid in northward advection of a partially modified Gulf air mass (boundary-layer dewpoints of 55-60 F). Strong surface heating/mixing across KS/OK will result in a narrow surface warm sector with moderate buoyancy (MLCAPE near 1000 J/kg) by mid-late afternoon across eastern KS. The eastern extent of the surface warm sector will be demarcated by a warm front into western MO. Surface-based thunderstorm development will be possible by roughly 22-00z along a surface trough/cold front across eastern KS, with subsequent expansion of elevated convection farther northeast across northern MO/southern IA through early tonight in a zone of strengthening low-level warm advection. Isolated strong outflow gusts (50-60 mph) will be possible with the initial storms across eastern KS this evening in the zone of steeper low-level lapse rates. Steep midlevel lapse rates, moderate buoyancy, and sufficiently long/curved hodographs will support some potential for embedded supercells capable of producing isolated large hail (1-1.75 inch diameter) into early tonight. The area from eastern KS to northwest MO was considered for a SLGT risk upgrade, and this area will be monitored closely in later outlook updates. ..Thompson/Goss.. 10/24/2024 Read more