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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Tue Sep 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...20z Update... Model and observational trends continue to suggest widespread wetting rainfall is likely over much of the central and northern High Plains late D1/Tuesday into early D2/Wednesday. Thus, despite strong winds and pockets of lower humidity, the availability of dry fuels appears limited. See the previous discussion for more details. ..Lyons.. 09/17/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Tue Sep 17 2024/ ...Synopsis... Strong deep-layer southwesterly flow will overspread the Dakotas, within the base of a negatively tilted midlevel trough/low moving northeastward across the northern High Plains. A tight pressure gradient peripheral to a related surface cyclone over eastern MT will promote strong post-frontal surface winds across western SD. While these winds and around 20 percent RH would typically warrant fire-weather highlights, substantial precipitation over the past week, and additional expected rainfall on Day 1/Tuesday, limit confidence in fuel receptiveness. ...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 0242 PM CDT Tue Sep 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...20z Update... Model and observational trends continue to suggest widespread wetting rainfall is likely over much of the central and northern High Plains late D1/Tuesday into early D2/Wednesday. Thus, despite strong winds and pockets of lower humidity, the availability of dry fuels appears limited. See the previous discussion for more details. ..Lyons.. 09/17/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Tue Sep 17 2024/ ...Synopsis... Strong deep-layer southwesterly flow will overspread the Dakotas, within the base of a negatively tilted midlevel trough/low moving northeastward across the northern High Plains. A tight pressure gradient peripheral to a related surface cyclone over eastern MT will promote strong post-frontal surface winds across western SD. While these winds and around 20 percent RH would typically warrant fire-weather highlights, substantial precipitation over the past week, and additional expected rainfall on Day 1/Tuesday, limit confidence in fuel receptiveness. ...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 0242 PM CDT Tue Sep 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...20z Update... Model and observational trends continue to suggest widespread wetting rainfall is likely over much of the central and northern High Plains late D1/Tuesday into early D2/Wednesday. Thus, despite strong winds and pockets of lower humidity, the availability of dry fuels appears limited. See the previous discussion for more details. ..Lyons.. 09/17/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Tue Sep 17 2024/ ...Synopsis... Strong deep-layer southwesterly flow will overspread the Dakotas, within the base of a negatively tilted midlevel trough/low moving northeastward across the northern High Plains. A tight pressure gradient peripheral to a related surface cyclone over eastern MT will promote strong post-frontal surface winds across western SD. While these winds and around 20 percent RH would typically warrant fire-weather highlights, substantial precipitation over the past week, and additional expected rainfall on Day 1/Tuesday, limit confidence in fuel receptiveness. ...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 0242 PM CDT Tue Sep 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...20z Update... Model and observational trends continue to suggest widespread wetting rainfall is likely over much of the central and northern High Plains late D1/Tuesday into early D2/Wednesday. Thus, despite strong winds and pockets of lower humidity, the availability of dry fuels appears limited. See the previous discussion for more details. ..Lyons.. 09/17/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Tue Sep 17 2024/ ...Synopsis... Strong deep-layer southwesterly flow will overspread the Dakotas, within the base of a negatively tilted midlevel trough/low moving northeastward across the northern High Plains. A tight pressure gradient peripheral to a related surface cyclone over eastern MT will promote strong post-frontal surface winds across western SD. While these winds and around 20 percent RH would typically warrant fire-weather highlights, substantial precipitation over the past week, and additional expected rainfall on Day 1/Tuesday, limit confidence in fuel receptiveness. ...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 0242 PM CDT Tue Sep 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...20z Update... Model and observational trends continue to suggest widespread wetting rainfall is likely over much of the central and northern High Plains late D1/Tuesday into early D2/Wednesday. Thus, despite strong winds and pockets of lower humidity, the availability of dry fuels appears limited. See the previous discussion for more details. ..Lyons.. 09/17/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Tue Sep 17 2024/ ...Synopsis... Strong deep-layer southwesterly flow will overspread the Dakotas, within the base of a negatively tilted midlevel trough/low moving northeastward across the northern High Plains. A tight pressure gradient peripheral to a related surface cyclone over eastern MT will promote strong post-frontal surface winds across western SD. While these winds and around 20 percent RH would typically warrant fire-weather highlights, substantial precipitation over the past week, and additional expected rainfall on Day 1/Tuesday, limit confidence in fuel receptiveness. ...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 0242 PM CDT Tue Sep 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...20z Update... Model and observational trends continue to suggest widespread wetting rainfall is likely over much of the central and northern High Plains late D1/Tuesday into early D2/Wednesday. Thus, despite strong winds and pockets of lower humidity, the availability of dry fuels appears limited. See the previous discussion for more details. ..Lyons.. 09/17/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Tue Sep 17 2024/ ...Synopsis... Strong deep-layer southwesterly flow will overspread the Dakotas, within the base of a negatively tilted midlevel trough/low moving northeastward across the northern High Plains. A tight pressure gradient peripheral to a related surface cyclone over eastern MT will promote strong post-frontal surface winds across western SD. While these winds and around 20 percent RH would typically warrant fire-weather highlights, substantial precipitation over the past week, and additional expected rainfall on Day 1/Tuesday, limit confidence in fuel receptiveness. ...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 0242 PM CDT Tue Sep 17 2024 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...20z Update... Model and observational trends continue to suggest widespread wetting rainfall is likely over much of the central and northern High Plains late D1/Tuesday into early D2/Wednesday. Thus, despite strong winds and pockets of lower humidity, the availability of dry fuels appears limited. See the previous discussion for more details. ..Lyons.. 09/17/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Tue Sep 17 2024/ ...Synopsis... Strong deep-layer southwesterly flow will overspread the Dakotas, within the base of a negatively tilted midlevel trough/low moving northeastward across the northern High Plains. A tight pressure gradient peripheral to a related surface cyclone over eastern MT will promote strong post-frontal surface winds across western SD. While these winds and around 20 percent RH would typically warrant fire-weather highlights, substantial precipitation over the past week, and additional expected rainfall on Day 1/Tuesday, limit confidence in fuel receptiveness. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Tue Sep 17 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from mid-afternoon to early evening on Thursday across central to eastern Minnesota and north-central Iowa. ...Upper Midwest... Minor adjustments (mainly eastward expansion) to severe probabilities have been made based on latest forecast guidance for the Day 3/Thursday period, but overall forecast philosophy remains unchanged from the previous outlook. A negatively tilted upper shortwave trough will shift east/northeast from the northern Plains/Canadian Prairies toward the Upper Midwest and western Ontario. Mid/upper west/southwesterly flow will remain somewhat enhanced (around 30-40 kt 850-700 mb flow) through around 00z before the system as a whole weakens. At the surface, a cold front will extend roughly north to south/southwest from western MN into southeast NE at midday. Ahead of this feature, southerly low-level flow will maintain 60s F dewpoints across IA into eastern MN/western WI. The warm sector will remain rather narrow due to generally high pressure and a drier boundary layer over much of the Midwest east of the MS River. Nevertheless, within the axis of greater moisture/low-level theta-e, around 1000-2000 J/kg MLCAPE is forecast. Organized thunderstorm clusters and line segments will pose a risk of isolated severe gusts and hail through early evening. The severe risk should rapidly diminish beyond 00z with loss of daytime heating, limited moisture/instability with eastward extent, and weakening deep-layer flow. ..Leitman.. 09/17/2024 Read more