SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 PM CDT Thu Oct 03 2024 Valid 040100Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT ACROSS PARTS OF SOUTHEASTERN IOWA...ADJACENT NORTHEASTERN MISSOURI AND WEST CENTRAL ILLINOIS... ...SUMMARY... An area of developing thunderstorms overnight may pose a risk for small to marginally severe hail across parts of southeastern Iowa, adjacent northeastern Missouri and west central Illinois. ...01Z Update... Within the mid-latitude westerlies, one notable short wave trough is forecast to continue digging across the northern Great Plains Red River Valley toward the upper Great Lakes region tonight. The southern periphery of the surrounding cyclonic mid/upper-level flow currently curves across southern Nebraska through the Missouri/Iowa border vicinity, where it is beginning to overspread an initially quasi-stationary frontal zone. Models suggest that this regime will become increasingly divergent late this evening into the overnight hours, contributing to increasing forcing for ascent. Lower/mid-level ascent is already increasing across Iowa and surrounding portions of the Missouri Valley/Upper Midwest, in response to warm advection. It appears that this will lead to increasing thunderstorm development by 05-07Z across parts of central/southern Iowa, where guidance indicates a corridor of modest destabilization is possible associated with weak elevated moisture return above the frontal zone. Forecast soundings indicate most unstable CAPE may increase in excess of 1000 J/kg along this corridor, in the presence of modest potential cloud-bearing layer shear. Thermodynamic profiles may include sufficiently cool mid-levels (and steep lapse rates) to support a risk for marginally severe hail (up to around 1 inch or so in diameter) in a few of the stronger storms. ..Kerr.. 10/04/2024 Read more

No Mesoscale Discussions are in effect as of Thu Oct 3 23:30:02 UTC 2024.

No watches are valid as of Thu Oct 3 23:30:02 UTC 2024.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0325 PM CDT Thu Oct 03 2024 Valid 051200Z - 111200Z Fire weather concerns will continue into the weekend across portions of the Rockies and into the central Plains. Long-range guidance continues to show good agreement in the evolution and progression of an upper-level trough (currently noted in water-vapor imagery across the northeast Pacific) across the Pacific Northwest and north-central U.S. through Saturday. A dry cold front is forecast to push southeast from the northern High Plains into the central Plains and Midwest through the day Saturday evening as an attendant surface low tracks across the southern Canadian Prairies in tandem with the upper wave. Dry, windy conditions behind this front will support widespread fire weather concerns. Upper-level ridging is expected to build across the western to central CONUS in the wake of Saturday's trough, which will result in unseasonably warm and dry conditions across the western two-thirds of the country. However, weak gradient winds limit predictability of widespread fire concerns heading into next week. ...D3/Saturday - Central Rockies into the Central Plains... Forecast guidance continues to show a strong wind signal ahead of and behind Saturday's cold front. Long-range ensembles show reasonably high probability for 20-30 mph winds across southern WY and from northern NE into the Dakotas. The strongest winds will likely occur across ND under the mid-level jet max, but cooler temperatures may limit RH reductions and limit confidence in the northern extent of the fire threat. Confidence in favorable overlap of strong winds, 15-20% RH, and receptive fuels increases with southward extent with the greatest fire threat expected from southern WY into central NE and far southern SD. The fire threat may peak during the mid/late morning hours across the central High Plains within the westerly downslope flow regime ahead of the front, followed by a wind shift with slightly higher RH, but strong northerly winds. Elevated to critical fire weather conditions are possible further southeast from central KS into western IA within the pre-frontal dry return regime where fuels have been slowly drying. ..Moore.. 10/03/2024 ...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 0325 PM CDT Thu Oct 03 2024 Valid 051200Z - 111200Z Fire weather concerns will continue into the weekend across portions of the Rockies and into the central Plains. Long-range guidance continues to show good agreement in the evolution and progression of an upper-level trough (currently noted in water-vapor imagery across the northeast Pacific) across the Pacific Northwest and north-central U.S. through Saturday. A dry cold front is forecast to push southeast from the northern High Plains into the central Plains and Midwest through the day Saturday evening as an attendant surface low tracks across the southern Canadian Prairies in tandem with the upper wave. Dry, windy conditions behind this front will support widespread fire weather concerns. Upper-level ridging is expected to build across the western to central CONUS in the wake of Saturday's trough, which will result in unseasonably warm and dry conditions across the western two-thirds of the country. However, weak gradient winds limit predictability of widespread fire concerns heading into next week. ...D3/Saturday - Central Rockies into the Central Plains... Forecast guidance continues to show a strong wind signal ahead of and behind Saturday's cold front. Long-range ensembles show reasonably high probability for 20-30 mph winds across southern WY and from northern NE into the Dakotas. The strongest winds will likely occur across ND under the mid-level jet max, but cooler temperatures may limit RH reductions and limit confidence in the northern extent of the fire threat. Confidence in favorable overlap of strong winds, 15-20% RH, and receptive fuels increases with southward extent with the greatest fire threat expected from southern WY into central NE and far southern SD. The fire threat may peak during the mid/late morning hours across the central High Plains within the westerly downslope flow regime ahead of the front, followed by a wind shift with slightly higher RH, but strong northerly winds. Elevated to critical fire weather conditions are possible further southeast from central KS into western IA within the pre-frontal dry return regime where fuels have been slowly drying. ..Moore.. 10/03/2024 ...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 0236 PM CDT Thu Oct 03 2024 Valid 032000Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast. However, a few strong storms are expected over parts of Iowa tonight. ...20Z Update... Scattered storms persist across the central FL Peninsula within a moist easterly flow regime south of the upper ridge. Moderate instability may support locally strong gusts within the diurnal and weakly sheared regime. To the west, a small area of strong thunderstorm potential is forecast from IA into northwest IL after 06Z, in association with a shortwave trough moving across the upper MS Valley. Lift near the 850 mb front along with steepening lapse rates may yield an elevated cluster of storms forming over south-central IA. Radar presentation of the initial activity may indicate hail in the strongest storm cores, but this may be short lived due to merging updrafts over time. While severe hail is not currently forecast, at least small hail appears likely. ..Jewell.. 10/03/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Thu Oct 03 2024/ ...Synopsis/Discussion... Morning surface observations depict a southwest/northeast-oriented quasi-stationary boundary extending from the central Plains into the Mid/Upper MS Valley. Within the base of a large-scale trough over the north-central CONUS, an embedded shortwave trough and related lift will overspread the boundary during the overnight/early morning hours. The associated low-level mass response will favor the east-northeastward movement of a weak frontal-wave low along the boundary -- promoting isolated to widely scattered elevated thunderstorms atop the frontal surface in the 06-12Z time frame (generally focused over eastern IA and northwest IL). Around 30-40 kt of effective shear could lead to a couple embedded cells capable of small to marginally severe hail initially, though the steeper midlevel lapse-rate plume and favorable instability should be displaced to the south of this activity -- generally limiting the severe threat. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Oct 03 2024 Valid 032000Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast. However, a few strong storms are expected over parts of Iowa tonight. ...20Z Update... Scattered storms persist across the central FL Peninsula within a moist easterly flow regime south of the upper ridge. Moderate instability may support locally strong gusts within the diurnal and weakly sheared regime. To the west, a small area of strong thunderstorm potential is forecast from IA into northwest IL after 06Z, in association with a shortwave trough moving across the upper MS Valley. Lift near the 850 mb front along with steepening lapse rates may yield an elevated cluster of storms forming over south-central IA. Radar presentation of the initial activity may indicate hail in the strongest storm cores, but this may be short lived due to merging updrafts over time. While severe hail is not currently forecast, at least small hail appears likely. ..Jewell.. 10/03/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Thu Oct 03 2024/ ...Synopsis/Discussion... Morning surface observations depict a southwest/northeast-oriented quasi-stationary boundary extending from the central Plains into the Mid/Upper MS Valley. Within the base of a large-scale trough over the north-central CONUS, an embedded shortwave trough and related lift will overspread the boundary during the overnight/early morning hours. The associated low-level mass response will favor the east-northeastward movement of a weak frontal-wave low along the boundary -- promoting isolated to widely scattered elevated thunderstorms atop the frontal surface in the 06-12Z time frame (generally focused over eastern IA and northwest IL). Around 30-40 kt of effective shear could lead to a couple embedded cells capable of small to marginally severe hail initially, though the steeper midlevel lapse-rate plume and favorable instability should be displaced to the south of this activity -- generally limiting the severe threat. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 PM CDT Thu Oct 03 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Discussion... A strong mid-level short-wave trough within fast northern-stream flow over the northern U.S. will cross the northern Plains and eventually move into the Upper Great Lakes region Saturday. Accompanying this trough, a surface low will advance quickly across the Canadian Prairie while a trailing cold front shifts southeastward across the northern and eventually the central Plains, and the Upper Midwest region, through the period. Scattered showers and a few thunderstorms should again affect southeastern Atlantic and Gulf Coast areas, while showers and thunderstorms also evolve during the afternoon and evening across the Upper Mississippi Valley/Upper Great Lakes area. Here, modest low-level moisture but steepening mid-level lapse rates suggests that convection should remain largely elevated atop a weakly stable boundary layer. Still, with strong west-southwesterly flow through the lower half of the troposphere, a few stronger updrafts -- possibly capable of producing hail or even locally gusty winds -- may occur. At this time, any risk for severe-caliber events appears likely to remain low, and thus no hail/wind probabilities will be included at this time. ..Goss.. 10/03/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 PM CDT Thu Oct 03 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Discussion... A strong mid-level short-wave trough within fast northern-stream flow over the northern U.S. will cross the northern Plains and eventually move into the Upper Great Lakes region Saturday. Accompanying this trough, a surface low will advance quickly across the Canadian Prairie while a trailing cold front shifts southeastward across the northern and eventually the central Plains, and the Upper Midwest region, through the period. Scattered showers and a few thunderstorms should again affect southeastern Atlantic and Gulf Coast areas, while showers and thunderstorms also evolve during the afternoon and evening across the Upper Mississippi Valley/Upper Great Lakes area. Here, modest low-level moisture but steepening mid-level lapse rates suggests that convection should remain largely elevated atop a weakly stable boundary layer. Still, with strong west-southwesterly flow through the lower half of the troposphere, a few stronger updrafts -- possibly capable of producing hail or even locally gusty winds -- may occur. At this time, any risk for severe-caliber events appears likely to remain low, and thus no hail/wind probabilities will be included at this time. ..Goss.. 10/03/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0128 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE NORTHERN GREAT BASIN AND SOUTHEASTERN PACIFIC NORTHWEST... The primary adjustment for this forecast update was a consolidation of the separate Elevated risk areas. Latest forecast guidance continues to trend towards increasing winds across much of the Pacific Northwest and northern Rockies. As such, dry and windy downslope conditions are expected in the lee of most prominent mountain ranges across the region. While some gaps in dry/windy conditions are anticipated, the majority of the northern Rockies will see the potential for elevated to critical fire weather conditions. Consideration was given for additional Critical risk areas across southwest MT and central WY, but the strongest winds will likely remain somewhat confined to the lee of terrain features, casting some uncertainty into the coverage of critical conditions. An expansion of the Elevated risk area across central to eastern MT was also considered as the cold front pushes east overnight. While drier solutions hint that elevated conditions are possible in the immediate wake of the front, ensemble guidance shows muted probabilities (30-40%) for reaching elevated criteria (likely due to the influence of nocturnal cooling). Trends will continue to be monitored for additional risk highlights across these regions. ..Moore.. 10/03/2024 .PREV DISCUSSION... /ISSUED 0221 AM CDT Thu Oct 03 2024/ ...Synopsis... A strong mid-level trough will approach and eventually overspread the Pacific Northwest on Friday. Ahead of this trough, a strong surface cyclone will develop in Alberta, which will result in a tightening surface pressure gradient across much of the Pacific Northwest and the northern Rockies. In addition, 60+ mph of mid-level flow will move across the Northwest and northern Great Basin. This stronger mid-level flow will overspread a deeply mixed airmass across southeast Oregon and northern Nevada and vicinity, which will result in even stronger winds across this region. Sustained winds of 25 to 30 mph are expected with relative humidity ranging from 15 percent to 25 percent. Given the critically dry nature of the fuels in this area, a Critical delineation was warranted. As the pressure gradient tightens across the northern Rockies and northern Plains, strong winds are expected to develop both across southern Wyoming and from the Nebraska Panhandle northward across the western Dakotas. Single-digit relative humidities are forecast across southern Wyoming with 15 to 25 percent relative humidity in the Plains. An Elevated delineation is warranted for both areas, and if winds trend stronger in Wyoming or relative humidity drier in the Plains, a Critical area may also need to be considered in these areas in later outlooks. ...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 1225 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Friday. ...Discussion... A fast/progressive upper flow field will persist across the northern third of the U.S. Friday, while ridging generally prevails over the southern two-thirds of the country. Once exception will be a weak upper disturbance shifting out of the northern Gulf of Mexico, which will partially phase with a northern-stream trough crossing the Great Lakes region. By the end of the period, this trough will reach New England and the Atlantic Coast. At the surface, a cold front will cross the northern Intermountain region and eventually emerge into the northern Plains, ahead of a trough embedded in the fast northern-stream flow field aloft. Otherwise, a rather nondescript surface pattern will prevail elsewhere. At low levels, tropical moisture will be confined to the Gulf and Southeast Coasts. Lesser moisture -- dewpoints in the upper 50s to low 60s -- will extend northward across the Tennessee, Ohio, Mid-Mississippi, and Mid Missouri Valleys, but weak lapse rates aloft across these areas will yield only modest destabilization. Greatest thunderstorm potential will extend from the Texas Coastal Plain eastward across the Southeast -- aided by ascent associated with the aforementioned southeastern U.S. upper disturbance phasing with a northern-stream trough, and other vorticity maxima extending westward across the Gulf and into northern Mexico. Elevated showers and a few thunderstorms will also be possible early in the period over the northeastern Missouri/southeastern Iowa/northern Illinois area. In all of these locales, severe weather is not expected. ..Goss.. 10/03/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Friday. ...Discussion... A fast/progressive upper flow field will persist across the northern third of the U.S. Friday, while ridging generally prevails over the southern two-thirds of the country. Once exception will be a weak upper disturbance shifting out of the northern Gulf of Mexico, which will partially phase with a northern-stream trough crossing the Great Lakes region. By the end of the period, this trough will reach New England and the Atlantic Coast. At the surface, a cold front will cross the northern Intermountain region and eventually emerge into the northern Plains, ahead of a trough embedded in the fast northern-stream flow field aloft. Otherwise, a rather nondescript surface pattern will prevail elsewhere. At low levels, tropical moisture will be confined to the Gulf and Southeast Coasts. Lesser moisture -- dewpoints in the upper 50s to low 60s -- will extend northward across the Tennessee, Ohio, Mid-Mississippi, and Mid Missouri Valleys, but weak lapse rates aloft across these areas will yield only modest destabilization. Greatest thunderstorm potential will extend from the Texas Coastal Plain eastward across the Southeast -- aided by ascent associated with the aforementioned southeastern U.S. upper disturbance phasing with a northern-stream trough, and other vorticity maxima extending westward across the Gulf and into northern Mexico. Elevated showers and a few thunderstorms will also be possible early in the period over the northeastern Missouri/southeastern Iowa/northern Illinois area. In all of these locales, severe weather is not expected. ..Goss.. 10/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1123 AM CDT Thu Oct 03 2024 Valid 031630Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis/Discussion... Morning surface observations depict a southwest/northeast-oriented quasi-stationary boundary extending from the central Plains into the Mid/Upper MS Valley. Within the base of a large-scale trough over the north-central CONUS, an embedded shortwave trough and related lift will overspread the boundary during the overnight/early morning hours. The associated low-level mass response will favor the east-northeastward movement of a weak frontal-wave low along the boundary -- promoting isolated to widely scattered elevated thunderstorms atop the frontal surface in the 06-12Z time frame (generally focused over eastern IA and northwest IL). Around 30-40 kt of effective shear could lead to a couple embedded cells capable of small to marginally severe hail initially, though the steeper midlevel lapse-rate plume and favorable instability should be displaced to the south of this activity -- generally limiting the severe threat. ..Weinman.. 10/03/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1123 AM CDT Thu Oct 03 2024 Valid 031630Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis/Discussion... Morning surface observations depict a southwest/northeast-oriented quasi-stationary boundary extending from the central Plains into the Mid/Upper MS Valley. Within the base of a large-scale trough over the north-central CONUS, an embedded shortwave trough and related lift will overspread the boundary during the overnight/early morning hours. The associated low-level mass response will favor the east-northeastward movement of a weak frontal-wave low along the boundary -- promoting isolated to widely scattered elevated thunderstorms atop the frontal surface in the 06-12Z time frame (generally focused over eastern IA and northwest IL). Around 30-40 kt of effective shear could lead to a couple embedded cells capable of small to marginally severe hail initially, though the steeper midlevel lapse-rate plume and favorable instability should be displaced to the south of this activity -- generally limiting the severe threat. ..Weinman.. 10/03/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1021 AM CDT Thu Oct 03 2024 Valid 031700Z - 041200Z The previous forecast remains on track. Consideration was made for introducing a risk area to portions of central to northeast NE and far northwest IA for this afternoon. Morning guidance continues to show a strong signal for sustained 20-25 mph winds this afternoon with the potential for gusts up to 30-35 mph. However, most 12 UTC solutions, including several HREF members, are showing a pronounced 5-10 F warm bias across the central Plains based on 15 UTC observations. Solutions that have captured recent temperature/dewpoint trends well suggest RH will only fall to the 25-30% range by late afternoon. Consequently, confidence in sustained elevated conditions remains very limited and precludes risk highlights. Further south across the southern High Plains, elevated wind/RH criteria will likely be met as winds increase on either side of a surface trough. However, fuel dryness does not appear sufficient to support a robust fire concern based on recent fuel guidance. ..Moore.. 10/03/2024 .PREV DISCUSSION... /ISSUED 0217 AM CDT Thu Oct 03 2024/ ...Synopsis... Shortwave ridging will traverse the western CONUS today. As this occurs, high pressure will also build into the northern Plains. Some breezy conditions are probable this afternoon in the wake of a cold front across the central Plains. However, relative humidities will not be that low (25-30 percent), and the strongest winds will likely be displaced south of the driest fuels. Therefore, no Elevated area is warranted today. However, warm and dry conditions will prevail across most of the western CONUS and result in continued drying of fuels. ...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 0736 AM CDT Thu Oct 03 2024 Valid 031300Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis/Discussion... In mid/upper levels, a nearly zonal northern-stream pattern will prevail either side of the Canadian border, from the Pacific Coast across the Great Lakes to New England. The main feature perturbing that belt for this period will be a strongly positively tilted trough, currently over south-central parts of SK/MB northwestward to north-central AB. This trough will amplify and pivot southeastward/ eastward across northern ON, northern MN and Lake Superior into tonight. By 12Z, the trailing part of this feature should be moving across the western U.P of MI, northern WI and central MN. A weak shortwave trough -- evident in moisture-channel imagery over eastern OR and southwestern ID -- may reach the Quad Cities area of IA/IL by 12Z tomorrow and phase with the larger trough. At the surface, 11Z analysis showed a frontal wave low over northwestern KS, with warm front eastward to west-central/ northwestern MO, and cold front across east-central CO. The low should migrate eastward through the period, reaching north-central/ northwestern MO by 12Z, with cold front trailing across southern KS, western OK and the TX South Plains, and warm front extending to east-central MO and southern IL. ...Mid/upper Mississippi Valley... Capping and meager boundary-layer moisture will inhibit convective potential today along/ahead of the front and low. However, an area of isolated to scattered elevated thunderstorms is possible overnight northeast of the low, supported by large-scale DCVA/lift ahead of the ejecting shortwave trough, and warm advection/ isentropic lift to LFC of increasingly moist parcels above the surface. Activity should be rooted in the 700-800-mb layer, amidst MUCAPE roughly 500-800 J/kg, and around 35-40 kt effective-shear magnitudes. This may support small hail, especially early in the convective cycle when cells are still at least somewhat discrete. Modes should become messier and precip more expansive fairly quickly, as inflow-layer moisture and MUCAPE only slowly increase in the immediate upstream airmass to the southwest. The overall severe threat appears too limited and conditional for an outlook at this time. ..Edwards/Dean.. 10/03/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0339 AM CDT Thu Oct 03 2024 Valid 061200Z - 111200Z ...DISCUSSION... A strong upper trough will broaden across the Upper Midwest into parts of the Northeast on Sunday. An associated cold front will move through the upper Ohio Valley on Sunday and off the Mid-Atlantic Coast early to mid morning on Monday. Thereafter, broad troughing will remain in the Northeast until late in the week as an expansive upper ridge envelops much of the CONUS. ...Upper-Ohio Valley Vicinity... The cold front will continue eastward on Sunday, moving through Ohio during the mid/late afternoon. Moisture return ahead of the front will be the main source of uncertainty in terms of how much severe threat there could be. Mid-level forcing will be sufficient, but low-level veering ahead of the front suggests uncertain storm coverage. A conditional threat for damaging winds exists during the late afternoon. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CDT Thu Oct 03 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Synopsis... A potent upper-level shortwave trough will make quick progress across the northern Plains and move into the upper Mississippi Valley by early evening. A deep surface cyclone within the Canadian Prairie will move east along with its parent upper-level system. Attendant to this cyclone, a cold front will quickly through Minnesota, Wisconsin, and eventually much of Michigan by early Sunday morning. ...Upper-Mississippi Valley Vicinity... Ahead of the cold front, some moisture return is expected to occur. However, this moisture return will have no connection to the Gulf due to a previous frontal passage to near the Gulf Coast. Lack of low-level moisture will likely preclude any potential for surface-based storms. By early evening, strong mid-level ascent, linear frontal forcing, and 850 mb warm air advection should promote scattered storm development from the Mississippi Valley into parts of Wisconsin. Deep-layer winds will be strong, but effective shear will only be marginal given the elevated nature of the convection. 500-1000 J/kg MUCAPE could support some stronger updrafts that could produce small hail. The marginal effective shear and messy storm modes should preclude any greater risk. ..Wendt.. 10/03/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CDT Thu Oct 03 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Synopsis... A potent upper-level shortwave trough will make quick progress across the northern Plains and move into the upper Mississippi Valley by early evening. A deep surface cyclone within the Canadian Prairie will move east along with its parent upper-level system. Attendant to this cyclone, a cold front will quickly through Minnesota, Wisconsin, and eventually much of Michigan by early Sunday morning. ...Upper-Mississippi Valley Vicinity... Ahead of the cold front, some moisture return is expected to occur. However, this moisture return will have no connection to the Gulf due to a previous frontal passage to near the Gulf Coast. Lack of low-level moisture will likely preclude any potential for surface-based storms. By early evening, strong mid-level ascent, linear frontal forcing, and 850 mb warm air advection should promote scattered storm development from the Mississippi Valley into parts of Wisconsin. Deep-layer winds will be strong, but effective shear will only be marginal given the elevated nature of the convection. 500-1000 J/kg MUCAPE could support some stronger updrafts that could produce small hail. The marginal effective shear and messy storm modes should preclude any greater risk. ..Wendt.. 10/03/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0221 AM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEAST OREGON...NORTHERN NEVADA...FAR NORTHEAST CALIFORNIA...AND SOUTHWEST IDAHO.... ...Synopsis... A strong mid-level trough will approach and eventually overspread the Pacific Northwest on Friday. Ahead of this trough, a strong surface cyclone will develop in Alberta, which will result in a tightening surface pressure gradient across much of the Pacific Northwest and the northern Rockies. In addition, 60+ mph of mid-level flow will move across the Northwest and northern Great Basin. This stronger mid-level flow will overspread a deeply mixed airmass across southeast Oregon and northern Nevada and vicinity, which will result in even stronger winds across this region. Sustained winds of 25 to 30 mph are expected with relative humidity ranging from 15 percent to 25 percent. Given the critically dry nature of the fuels in this area, a Critical delineation was warranted. As the pressure gradient tightens across the northern Rockies and northern Plains, strong winds are expected to develop both across southern Wyoming and from the Nebraska Panhandle northward across the western Dakotas. Single-digit relative humidities are forecast across southern Wyoming with 15 to 25 percent relative humidity in the Plains. An Elevated delineation is warranted for both areas, and if winds trend stronger in Wyoming or relative humidity drier in the Plains, a Critical area may also need to be considered in these areas in later outlooks. ..Bentley.. 10/03/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more