SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0334 PM CDT Mon Sep 30 2024 Valid 021200Z - 081200Z Fire weather concerns will persist intermittently through the extended period across the western half of the CONUS. Long-range ensemble guidance continues to show a general ridging pattern over the southern half of the country, which will continue to favor stronger mid/upper-level flow along the U.S./Canadian border. This regime will favor seasonal to above-normal temperatures for the Plains into the West and mostly dry conditions. Consequently, dry fuels will likely be maintained and gradually expand in coverage for many locations. Fire weather concerns will emerge as shortwave troughs embedded within the mean zonal flow (and their attendant surface lows/fronts) propagate across the northern CONUS. ...D3/Wednesday - Southern Wyoming... Strong zonal flow is expected to persist across the northern CONUS through late D3/Wednesday. This will maintain a downslope flow regime into the WY Basin with afternoon RH values forecast to reach into the teens to low 20s. Deterministic and ensemble guidance show a signal for 15-25 mph winds, and with ERCs generally near the 90th percentile, elevated to critical fire weather conditions appear likely. ...D3/Wednesday - Coastal Southern CA... Upper ridging over the Great Basin combined with a weak coastal low will promote a modest offshore flow regime across southern CA. Unseasonably hot temperatures will continue to dry fuels and maintain very dry conditions. Localized elevated fire weather conditions are possible - mainly within the higher coastal terrain - late Wednesday into early Thursday morning. ...D5/Friday - northern Great Basin... Latest water-vapor imagery reveals a broad upper trough over the central Pacific, which is forecast to reach the West Coast by D5/Friday. Stronger flow overspreading the Pacific Northwest will promote downslope winds and surface pressure falls in the lee of the Cascades/northern Sierra Nevada. While run-to-run trends continue to show some variability regarding the strength of the winds, recent European solutions, which typically under-forecast winds, align with latest GEFS wind probabilities and suggests fire weather concerns may emerge during D5/Friday afternoon. ...D6/Saturday - northern Rockies/High Plains... The upper trough that is forecast to reach the Pacific Northwest on D5/Friday is expected to migrate into the northern Plains through D6/Saturday. As this occurs, lee cyclogenesis is probable and should support strengthening low-level pressure gradient winds both ahead of and behind the primary surface trough/cold front. While some uncertainty remains regarding the degree of RH reductions across the region, very dry fuels already in place (ERCs well above the 90th percentile) combined with a strong wind signal hint that a fire concern is possible. Further adjustments/expansions into the Plains are possible as guidance continues to come into better alignment. ..Moore.. 09/30/2024 ...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 0258 PM CDT Mon Sep 30 2024 Valid 302000Z - 011200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN NORTH CAROLINA... ...SUMMARY... Isolated strong to possibly severe thunderstorms may affect central/eastern North Carolina through early evening. ...20z Update... The previous outlook remains on track, with isolated strong storms possible across eastern North Carolina through early evening. No changes are needed with the 20z update. ..Leitman.. 09/30/2024 .PREV DISCUSSION... /ISSUED 1108 AM CDT Mon Sep 30 2024/ ...NC... Late morning surface analysis and visible satellite imagery show a weak boundary extending across eastern NC. Strong heating will occur along and to the south of the boundary this afternoon, where dewpoints are in the mid 70s. Despite the high/increasing low level theta-e, CAPE profiles will be limited by poor mid-level lapse rates but will still be sufficient for scattered afternoon showers and thunderstorms. Low-level winds are weak, but forecast soundings show veering in the lowest 2km near the boundary, and sufficient southwesterly flow aloft for storm-scale organization. This suggests a scenario somewhat similar to yesterday in southern VA, albeit a little more favorable. A few rotating storms are possible, with some potential for a tornado or two or locally strong wind gusts with the more organized cells. Therefore have added a narrow MRGL risk area in vicinity of the surface boundary. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Mon Sep 30 2024 Valid 302000Z - 011200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN NORTH CAROLINA... ...SUMMARY... Isolated strong to possibly severe thunderstorms may affect central/eastern North Carolina through early evening. ...20z Update... The previous outlook remains on track, with isolated strong storms possible across eastern North Carolina through early evening. No changes are needed with the 20z update. ..Leitman.. 09/30/2024 .PREV DISCUSSION... /ISSUED 1108 AM CDT Mon Sep 30 2024/ ...NC... Late morning surface analysis and visible satellite imagery show a weak boundary extending across eastern NC. Strong heating will occur along and to the south of the boundary this afternoon, where dewpoints are in the mid 70s. Despite the high/increasing low level theta-e, CAPE profiles will be limited by poor mid-level lapse rates but will still be sufficient for scattered afternoon showers and thunderstorms. Low-level winds are weak, but forecast soundings show veering in the lowest 2km near the boundary, and sufficient southwesterly flow aloft for storm-scale organization. This suggests a scenario somewhat similar to yesterday in southern VA, albeit a little more favorable. A few rotating storms are possible, with some potential for a tornado or two or locally strong wind gusts with the more organized cells. Therefore have added a narrow MRGL risk area in vicinity of the surface boundary. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Mon Sep 30 2024 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR NORTHEAST MONTANA INTO NORTHWEST NORTH DAKOTA... ...Northern High Plains... The primary change for this forecast update is to introduce a Critical risk area to portions of northeast MT into northwestern ND. Latest ensemble guidance shows reasonably good agreement in several hours of sustained 20-25 mph with RH reductions into the low 20s and possibly upper teens under the low-level thermal trough. Critical conditions are possible further south along the High Plains into western SD and far northwest NE, but recent high-res guidance suggests such conditions may be more localized compared to areas further north. ...southern New Mexico and Arizona... Breezy, 15-20 mph pressure gradient winds are expected across southern NM into AZ tomorrow afternoon as surface high pressure builds along the southern High Plains. Unseasonably warm temperatures will promote 15-20% RH values by late afternoon. Elevated fire weather conditions are likely, but fuel status remains somewhat uncertain with ERCs generally near the 50-60th percentile based on recent fuel analyses. ..Moore.. 09/30/2024 .PREV DISCUSSION... /ISSUED 0117 AM CDT Mon Sep 30 2024/ ...Synopsis... On Tuesday, lee troughing will resume across Alberta, which will result in a strengthening pressure gradient and another cold front moving across the northern Rockies/northern Plains. Some dry and breezy conditions are possible ahead of and behind this cold front. Some drier/windier conditions are possible within the broader Elevated area which extends from north-central Montana to far northeast Colorado. However, confidence in where this may occur is too low at this time to add a Critical delineation. In addition, dry and breezy conditions are possible in terrain-favored regions of southern Wyoming. Fuels are also critically dry in this region and will dry further with dry and breezy conditions Monday. An Elevated area has been added to address this 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 0236 PM CDT Mon Sep 30 2024 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR NORTHEAST MONTANA INTO NORTHWEST NORTH DAKOTA... ...Northern High Plains... The primary change for this forecast update is to introduce a Critical risk area to portions of northeast MT into northwestern ND. Latest ensemble guidance shows reasonably good agreement in several hours of sustained 20-25 mph with RH reductions into the low 20s and possibly upper teens under the low-level thermal trough. Critical conditions are possible further south along the High Plains into western SD and far northwest NE, but recent high-res guidance suggests such conditions may be more localized compared to areas further north. ...southern New Mexico and Arizona... Breezy, 15-20 mph pressure gradient winds are expected across southern NM into AZ tomorrow afternoon as surface high pressure builds along the southern High Plains. Unseasonably warm temperatures will promote 15-20% RH values by late afternoon. Elevated fire weather conditions are likely, but fuel status remains somewhat uncertain with ERCs generally near the 50-60th percentile based on recent fuel analyses. ..Moore.. 09/30/2024 .PREV DISCUSSION... /ISSUED 0117 AM CDT Mon Sep 30 2024/ ...Synopsis... On Tuesday, lee troughing will resume across Alberta, which will result in a strengthening pressure gradient and another cold front moving across the northern Rockies/northern Plains. Some dry and breezy conditions are possible ahead of and behind this cold front. Some drier/windier conditions are possible within the broader Elevated area which extends from north-central Montana to far northeast Colorado. However, confidence in where this may occur is too low at this time to add a Critical delineation. In addition, dry and breezy conditions are possible in terrain-favored regions of southern Wyoming. Fuels are also critically dry in this region and will dry further with dry and breezy conditions Monday. An Elevated area has been added to address this threat. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 2128 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR EASTERN NORTH CAROLINA
Mesoscale Discussion 2128 NWS Storm Prediction Center Norman OK 1224 PM CDT Mon Sep 30 2024 Areas affected...eastern North Carolina Concerning...Severe potential...Watch unlikely Valid 301724Z - 301930Z Probability of Watch Issuance...20 percent SUMMARY...Isolated thunderstorms are expected this afternoon into early evening across eastern North Carolina. This activity should mostly be sub-severe, but sporadic strong gusts 45-60 mph and perhaps a brief spin-up or two will be possible. DISCUSSION...Thunderstorms will increase in coverage over the next couple of hours in the vicinity of a surface boundary draped across eastern NC. Temperatures in the upper 70s to low 80s F amid dewpoints in the low 70s F are contributing to modest MLCAPE across the region. Poor midlevel lapse rates should largely limit updraft intensity. However, pockets of steeper low-level lapse rates and moderate vertical shear should allow for transient organized cells capable of producing gusty winds. Vertically veering low-level winds amid locally enhanced low-level shear in the vicinity of the surface boundary will be responsible for somewhat enlarged, curved hodographs. Ongoing convection has shown some signs of weak rotation, and this should continue through the afternoon. Given the moist boundary-layer, a brief spin-up or two could occur. The overall environment is expected to remain marginal, and any stronger/organized convection will be sporadic/transient, precluding watch issuance. ..Leitman/Hart.. 09/30/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...MHX...RAH...ILM... LAT...LON 34407763 35047917 35367948 35987920 36327771 36257675 35787646 34797663 34407763 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1238 PM CDT Mon Sep 30 2024 Valid 021200Z - 031200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Wednesday. ...Synopsis... A quiet mid-level pattern for thunderstorms is expected across much of the CONUS with zonal flow over the north and a series of anticyclones/ridging across the south. Stable conditions in the north should preclude thunderstorm development with embedded low-amplitude shortwave impulses. Across the south, isolated thunderstorms will remain possible over the FL Peninsula, centered on the central portion, where the sea breeze should provide sufficient lift during the afternoon. Very isolated thunderstorms are also possible within a portion of the Mogollon Rim where limited mid-level moisture remains. ..Grams.. 09/30/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1238 PM CDT Mon Sep 30 2024 Valid 021200Z - 031200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Wednesday. ...Synopsis... A quiet mid-level pattern for thunderstorms is expected across much of the CONUS with zonal flow over the north and a series of anticyclones/ridging across the south. Stable conditions in the north should preclude thunderstorm development with embedded low-amplitude shortwave impulses. Across the south, isolated thunderstorms will remain possible over the FL Peninsula, centered on the central portion, where the sea breeze should provide sufficient lift during the afternoon. Very isolated thunderstorms are also possible within a portion of the Mogollon Rim where limited mid-level moisture remains. ..Grams.. 09/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Mon Sep 30 2024 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Tuesday. ...Discussion... Scattered thunderstorms are possible on Tuesday afternoon across the central FL Peninsula where a moderately buoyant air mass persists. A low-amplitude upper impulse will pass to its north across the Southeast, but deep-layer shear is expected to remain weak. In combination with marginal mid-level lapse rates, the severe-storm threat appears negligible. Across eastern NC to far southeast VA, a weakening shortwave trough will progress across the region and offshore Tuesday evening/night. Isolated thunderstorms will remain possible through the afternoon. Over the central to lower Great Lakes, a vigorous shortwave trough will move across ON and the northern Great Lakes. A surface cold front ahead of this trough will similarly move eastward, reaching Lower MI to IN by afternoon. With surface dewpoints in the low 60s, meager surface-based buoyancy should develop ahead of the front. But warm 700-mb temperatures and weak mid-level lapse rates, especially with southern extent along the front, suggest instability will remain limited and thunderstorm coverage will be sparse. With the bulk of stronger mid/upper flow lagging behind the front, severe storms are not anticipated. Limited mid-level moisture from the Mogollon Rim into southern AZ may promote very isolated thunderstorms during the afternoon. ..Grams.. 09/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Mon Sep 30 2024 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Tuesday. ...Discussion... Scattered thunderstorms are possible on Tuesday afternoon across the central FL Peninsula where a moderately buoyant air mass persists. A low-amplitude upper impulse will pass to its north across the Southeast, but deep-layer shear is expected to remain weak. In combination with marginal mid-level lapse rates, the severe-storm threat appears negligible. Across eastern NC to far southeast VA, a weakening shortwave trough will progress across the region and offshore Tuesday evening/night. Isolated thunderstorms will remain possible through the afternoon. Over the central to lower Great Lakes, a vigorous shortwave trough will move across ON and the northern Great Lakes. A surface cold front ahead of this trough will similarly move eastward, reaching Lower MI to IN by afternoon. With surface dewpoints in the low 60s, meager surface-based buoyancy should develop ahead of the front. But warm 700-mb temperatures and weak mid-level lapse rates, especially with southern extent along the front, suggest instability will remain limited and thunderstorm coverage will be sparse. With the bulk of stronger mid/upper flow lagging behind the front, severe storms are not anticipated. Limited mid-level moisture from the Mogollon Rim into southern AZ may promote very isolated thunderstorms during the afternoon. ..Grams.. 09/30/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1108 AM CDT Mon Sep 30 2024 Valid 301630Z - 011200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON OVER PORTIONS OF EASTERN NORTH CAROLINA... ...SUMMARY... Isolated strong to possibly severe thunderstorms may affect central/eastern North Carolina this afternoon. ...NC... Late morning surface analysis and visible satellite imagery show a weak boundary extending across eastern NC. Strong heating will occur along and to the south of the boundary this afternoon, where dewpoints are in the mid 70s. Despite the high/increasing low level theta-e, CAPE profiles will be limited by poor mid-level lapse rates but will still be sufficient for scattered afternoon showers and thunderstorms. Low-level winds are weak, but forecast soundings show veering in the lowest 2km near the boundary, and sufficient southwesterly flow aloft for storm-scale organization. This suggests a scenario somewhat similar to yesterday in southern VA, albeit a little more favorable. A few rotating storms are possible, with some potential for a tornado or two or locally strong wind gusts with the more organized cells. Therefore have added a narrow MRGL risk area in vicinity of the surface boundary. ..Hart/Weinman.. 09/30/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1108 AM CDT Mon Sep 30 2024 Valid 301630Z - 011200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON OVER PORTIONS OF EASTERN NORTH CAROLINA... ...SUMMARY... Isolated strong to possibly severe thunderstorms may affect central/eastern North Carolina this afternoon. ...NC... Late morning surface analysis and visible satellite imagery show a weak boundary extending across eastern NC. Strong heating will occur along and to the south of the boundary this afternoon, where dewpoints are in the mid 70s. Despite the high/increasing low level theta-e, CAPE profiles will be limited by poor mid-level lapse rates but will still be sufficient for scattered afternoon showers and thunderstorms. Low-level winds are weak, but forecast soundings show veering in the lowest 2km near the boundary, and sufficient southwesterly flow aloft for storm-scale organization. This suggests a scenario somewhat similar to yesterday in southern VA, albeit a little more favorable. A few rotating storms are possible, with some potential for a tornado or two or locally strong wind gusts with the more organized cells. Therefore have added a narrow MRGL risk area in vicinity of the surface boundary. ..Hart/Weinman.. 09/30/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1034 AM CDT Mon Sep 30 2024 Valid 301700Z - 011200Z ...CRITICAL FIRE WEATHER AREA FOR CENTRAL NEBRASKA TO CENTRAL SOUTH DAKOTA... The previous forecast remains on track with only minor adjustments needed based on trends in recent guidance. Mid-morning observations depict a strong cold front pushing southeast across the central and northern Plains. Post-frontal winds between 15-25 mph (gusting to 35-45 mph) are being reported with RH values beginning to fall with the diurnal heating cycle. Confidence remains high in several hours of critical fire weather conditions for central NE into central SD. 12z guidance that has captured the progression of the front and wind/RH trends the best - namely the RAP and HRRR - suggest dry/breezy post-frontal conditions may extended as far east as the MN/WI border by late afternoon, necessitating a slight eastward expansion of the Elevated risk area. Elevated wind/RH criteria may be met as far south as southeast CO, southern KS, and northwest OK later tonight; however, fuel conditions are not as dry compared to locations further north, and the strongest winds will likely be offset from peak heating. These concerns precluded a southward expansion despite reasonably high confidence in somewhat dry/windy conditions. ..Moore.. 09/30/2024 .PREV DISCUSSION... /ISSUED 0115 AM CDT Mon Sep 30 2024/ ...Synopsis... Very strong winds are in place behind a cold front which is moving across Montana early this morning. Some sustained winds over 30 mph have been reported with gusts over 50 mph. As this front moves southeast, these breezy conditions are expected to continue in the post-frontal airmass. Poor overnight recoveries are occurring across the central Plains this morning with some relative humidity less than 25-30 percent, which is expected to continue through morning. In the immediate wake of the cold front late this morning and during the early afternoon, relative humidities are expected to be low before colder air arrives. Therefore, some critical fire weather concerns are expected across portions of Nebraska and South Dakota this afternoon. Farther west, some dry and breezy conditions are possible in terrain-favored areas of northeast Utah and southwest Wyoming where an Elevated is in place to cover this threat. ...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 0737 AM CDT Mon Sep 30 2024 Valid 301300Z - 011200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today, though a few strong storms may affect central/eastern North Carolina. ...Synopsis/Discussion... The main belt of mid/upper-level, midlatitude westerlies will continue to traverse the northwestern/north-central CONUS and central/southwestern Canada, buckled cyclonically around a prominent synoptic trough now located from eastern SK to central MT and western WY. This trough should phase with another now over central mainland Arctic Canada by the end of the period, resulting in a 500-mb low over southeastern Nunavut, with trough trailing over western Hudson Bay, northwesternmost ON, MN, and IA. Strongly difluent flow aloft will take shape southeast of the trough, across the Mississippi Valley, the Great Lakes from Michigan/Huron on down, the Ohio Valley, and much of the Appalachians. As that occurs, a longstanding, filling, weakening low now over southwestern WV will devolve today to an open-wave trough, losing amplitude rapidly and drifting eastward over the central Appalachians through the period. Part of a basal shortwave trough/vorticity lobe -- now apparent in moisture-channel imagery over eastern TN -- will eject eastward across northern NC and southern VA from this afternoon through tonight. At the surface, 11Z analysis showed a quasistationary front across northern SC to just south of the southern Outer Banks, extending from a triple-point low near CAE. This boundary should shift northward over central/eastern NC through the day. Meanwhile, a cold front -- related to the strong northern-stream trough -- was drawn from central/southern MB across southern ND, central SD, northwestern NE, and southern WY. This front should sweep across most of the Great Plains and upper Mississippi Valley through the period, reaching northern Lower MI, IL, southwestern MO, southern OK, and the TX South Plains by 12Z. ...Central/eastern NC... Widely scattered showers and thunderstorms are expected to develop this afternoon over the Piedmont and coastal plain, in an environment characterized by rich boundary-layer moisture (surface dewpoints commonly in upper 60 to mid 70s F) very weak ambient MLCINH easily removed by diurnal heating, but weak mid/upper-level lapse rates. This will result in 500-1200 J/kg MLCAPE over most of the area from he Piedmont to the Sounds, beneath a belt of sufficiently strong mid/upper flow to yield around 35-45-kt effective-shear magnitudes. Low-level hodographs over central/eastern NC this afternoon, from model forecast soundings, reasonably show curvature near the frontal zone, but with weak speeds in the lowest couple km that substantially limit SRH and vector shear. However, above 1 km, hodographs are somewhat long and straight, suggesting the potential for low-end supercells amidst the mode common multicellular modes. At this time, forecast shear appears too weak to support an unconditional tornado-threat area, but the scenario will be monitored for any mesoscale enhancement to shear (especially along boundaries) that may introduce such a risk. The gust threat appears subsevere at this time, though localized gusts approaching severe limits cannot be ruled out. ..Edwards/Broyles.. 09/30/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0339 AM CDT Mon Sep 30 2024 Valid 031200Z - 081200Z ...DISCUSSION... Potential for severe weather continues to appear limited on Thursday and Friday as upper-level flow will remain primarily zonal across the CONUS along with a surface pattern that will not promote northward advection of moisture. By the weekend, the predictability of the upper-level pattern begins to decrease quickly. Both the GFS and ECMWF show flow trying to amplify in the northern half of the CONUS. However, the wave pattern between the two models is out of phase. The ECMWF would suggest at least some low potential for severe weather, given a greater southward advancement of an upper trough this weekend into early next week. Even if this evolution is to verify, this severe potential would be conditional on the magnitude and quality of moisture return after another front moves into the Gulf Coast region late next week. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0339 AM CDT Mon Sep 30 2024 Valid 031200Z - 081200Z ...DISCUSSION... Potential for severe weather continues to appear limited on Thursday and Friday as upper-level flow will remain primarily zonal across the CONUS along with a surface pattern that will not promote northward advection of moisture. By the weekend, the predictability of the upper-level pattern begins to decrease quickly. Both the GFS and ECMWF show flow trying to amplify in the northern half of the CONUS. However, the wave pattern between the two models is out of phase. The ECMWF would suggest at least some low potential for severe weather, given a greater southward advancement of an upper trough this weekend into early next week. Even if this evolution is to verify, this severe potential would be conditional on the magnitude and quality of moisture return after another front moves into the Gulf Coast region late next week. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 AM CDT Mon Sep 30 2024 Valid 021200Z - 031200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Wednesday. ...Synopsis... A zonal flow pattern aloft is expected to develop by Wednesday morning across the CONUS. The jet stream will be positioned along the Canadian border. Stable conditions in the northern tier of states should generally preclude thunderstorm development with any embedded shortwave troughs. Farther south, upper-level ridging will also minimize thunderstorm potential. Two exceptions are within the Florida Peninsula where the sea breeze will provide sufficient lift for storms during the afternoon. Isolated thunderstorms are also possible within a portion of the Mogollon Rim where mid-level moisture still remains. ..Wendt.. 09/30/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0117 AM CDT Mon Sep 30 2024 Valid 011200Z - 021200Z ...Synopsis... On Tuesday, lee troughing will resume across Alberta, which will result in a strengthening pressure gradient and another cold front moving across the northern Rockies/northern Plains. Some dry and breezy conditions are possible ahead of and behind this cold front. Some drier/windier conditions are possible within the broader Elevated area which extends from north-central Montana to far northeast Colorado. However, confidence in where this may occur is too low at this time to add a Critical delineation. In addition, dry and breezy conditions are possible in terrain-favored regions of southern Wyoming. Fuels are also critically dry in this region and will dry further with dry and breezy conditions Monday. An Elevated area has been added to address this threat. ..Bentley.. 09/30/2024 ...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 0115 AM CDT Mon Sep 30 2024 Valid 301200Z - 011200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE CENTRAL AND NORTHERN PLAINS.... ...Synopsis... Very strong winds are in place behind a cold front which is moving across Montana early this morning. Some sustained winds over 30 mph have been reported with gusts over 50 mph. As this front moves southeast, these breezy conditions are expected to continue in the post-frontal airmass. Poor overnight recoveries are occurring across the central Plains this morning with some relative humidity less than 25-30 percent, which is expected to continue through morning. In the immediate wake of the cold front late this morning and during the early afternoon, relative humidities are expected to be low before colder air arrives. Therefore, some critical fire weather concerns are expected across portions of Nebraska and South Dakota this afternoon. Farther west, some dry and breezy conditions are possible in terrain-favored areas of northeast Utah and southwest Wyoming where an Elevated is in place to cover this threat. ..Bentley.. 09/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1158 PM CDT Sun Sep 29 2024 Valid 011200Z - 021200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Tuesday. ...Synopsis... A weakening shortwave trough will progress east over the Lower Mid-Atlantic States on Tuesday and offshore Tuesday night. Isolated thunderstorms will be possible over eastern North Carolina to far southeast Virginia during the afternoon before the trough departs. A strong upper-level trough will move across parts of the northern Great Lakes. A surface cold front associated with this trough will similarly move eastward, progressing into the lower Ohio Valley and the lower Great Lakes through the afternoon and evening. With surface dewpoints in the low 60s, marginal surface-based buoyancy of 500-750 J/kg MLCAPE could develop ahead of the front. Warm 700 mb temperatures and weak low-level winds suggest severe storms are unlikely. Elsewhere, widely scattered to scattered storms are possible in the Florida Peninsula where sea breeze boundaries are likely to initiate storms in a moist environment. Mid-level moisture near the Mogollon Rim into parts of southern Arizona may promote isolated thunderstorm development during the afternoon. ..Wendt.. 09/30/2024 Read more