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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Thu Sep 19 2024 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms are possible on Saturday afternoon to early evening in the southern High Plains. ...Southern High Plains... In advance of a southern-stream shortwave trough reaching the Four Corners, a 50-65 kt 500-mb jetlet is forecast to eject over NM by early evening Saturday. This will yield favorable deep-layer shear for organized storms across eastern NM into parts of northwest TX. Strengthening large-scale ascent within a low-level warm/moist conveyor should overspread this region by Saturday morning. This should yield early-period convection and renders moderate uncertainty over the degree of destabilization by afternoon. Still, with ample boundary-layer heating to the south of early-day activity, a plume of at least weak-surface based buoyancy should develop. Renewed afternoon to early evening thunderstorms should be capable of producing at least isolated severe. Steep mid-level lapse rates should be confined along and west of the Sangre de Cristo Mountains, rendering further uncertainty over the intensity and coverage of the severe threat. The eastern extent of the threat should be curtailed by the confined buoyancy plume and decreasing instability deeper into TX/OK. ...Lower/Mid-MO Valley to the Upper MS Valley... A relatively complex and uncertain evolution to convective potential is evident on Saturday afternoon and evening. This region will largely remain within a low-amplitude mid-level ridge. This may flatten somewhat in between a southern-stream shortwave trough in the Southwest and a northern-stream trough over the southern Prairie Provinces to along the ND/MN international border. In association with the latter wave, a surface cold front should push southeast in the north-central states. Guidance varies with the degree of destabilization ahead of it, and especially with the spatial extent of afternoon/evening convection. As such, a severe threat area has not yet been delineated but may be warranted in later outlooks if predictability increases. ..Grams.. 09/19/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Thu Sep 19 2024 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms are possible on Saturday afternoon to early evening in the southern High Plains. ...Southern High Plains... In advance of a southern-stream shortwave trough reaching the Four Corners, a 50-65 kt 500-mb jetlet is forecast to eject over NM by early evening Saturday. This will yield favorable deep-layer shear for organized storms across eastern NM into parts of northwest TX. Strengthening large-scale ascent within a low-level warm/moist conveyor should overspread this region by Saturday morning. This should yield early-period convection and renders moderate uncertainty over the degree of destabilization by afternoon. Still, with ample boundary-layer heating to the south of early-day activity, a plume of at least weak-surface based buoyancy should develop. Renewed afternoon to early evening thunderstorms should be capable of producing at least isolated severe. Steep mid-level lapse rates should be confined along and west of the Sangre de Cristo Mountains, rendering further uncertainty over the intensity and coverage of the severe threat. The eastern extent of the threat should be curtailed by the confined buoyancy plume and decreasing instability deeper into TX/OK. ...Lower/Mid-MO Valley to the Upper MS Valley... A relatively complex and uncertain evolution to convective potential is evident on Saturday afternoon and evening. This region will largely remain within a low-amplitude mid-level ridge. This may flatten somewhat in between a southern-stream shortwave trough in the Southwest and a northern-stream trough over the southern Prairie Provinces to along the ND/MN international border. In association with the latter wave, a surface cold front should push southeast in the north-central states. Guidance varies with the degree of destabilization ahead of it, and especially with the spatial extent of afternoon/evening convection. As such, a severe threat area has not yet been delineated but may be warranted in later outlooks if predictability increases. ..Grams.. 09/19/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Thu Sep 19 2024 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms are possible on Saturday afternoon to early evening in the southern High Plains. ...Southern High Plains... In advance of a southern-stream shortwave trough reaching the Four Corners, a 50-65 kt 500-mb jetlet is forecast to eject over NM by early evening Saturday. This will yield favorable deep-layer shear for organized storms across eastern NM into parts of northwest TX. Strengthening large-scale ascent within a low-level warm/moist conveyor should overspread this region by Saturday morning. This should yield early-period convection and renders moderate uncertainty over the degree of destabilization by afternoon. Still, with ample boundary-layer heating to the south of early-day activity, a plume of at least weak-surface based buoyancy should develop. Renewed afternoon to early evening thunderstorms should be capable of producing at least isolated severe. Steep mid-level lapse rates should be confined along and west of the Sangre de Cristo Mountains, rendering further uncertainty over the intensity and coverage of the severe threat. The eastern extent of the threat should be curtailed by the confined buoyancy plume and decreasing instability deeper into TX/OK. ...Lower/Mid-MO Valley to the Upper MS Valley... A relatively complex and uncertain evolution to convective potential is evident on Saturday afternoon and evening. This region will largely remain within a low-amplitude mid-level ridge. This may flatten somewhat in between a southern-stream shortwave trough in the Southwest and a northern-stream trough over the southern Prairie Provinces to along the ND/MN international border. In association with the latter wave, a surface cold front should push southeast in the north-central states. Guidance varies with the degree of destabilization ahead of it, and especially with the spatial extent of afternoon/evening convection. As such, a severe threat area has not yet been delineated but may be warranted in later outlooks if predictability increases. ..Grams.. 09/19/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0121 AM CDT Thu Sep 19 2024 Valid 201200Z - 211200Z ...NO CRITICAL AREAS... ...Synopsis... A low-latitude midlevel low will advance eastward across the Lower CO River Valley, while a related belt of strong deep-layer southwesterly flow overspreads the Southwest. Boundary-layer mixing into this strong deep-layer flow will favor dry/breezy conditions across portions of western NM and eastern AZ during the afternoon. While this could lead to locally elevated fire-weather conditions, fuels are generally unsupportive of large-fire spread at this time. Elsewhere, a minimal overlap of breezy surface winds and low RH should limit fire-weather concerns. ..Weinman.. 09/19/2024 ...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 0121 AM CDT Thu Sep 19 2024 Valid 201200Z - 211200Z ...NO CRITICAL AREAS... ...Synopsis... A low-latitude midlevel low will advance eastward across the Lower CO River Valley, while a related belt of strong deep-layer southwesterly flow overspreads the Southwest. Boundary-layer mixing into this strong deep-layer flow will favor dry/breezy conditions across portions of western NM and eastern AZ during the afternoon. While this could lead to locally elevated fire-weather conditions, fuels are generally unsupportive of large-fire spread at this time. Elsewhere, a minimal overlap of breezy surface winds and low RH should limit fire-weather concerns. ..Weinman.. 09/19/2024 ...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 0121 AM CDT Thu Sep 19 2024 Valid 201200Z - 211200Z ...NO CRITICAL AREAS... ...Synopsis... A low-latitude midlevel low will advance eastward across the Lower CO River Valley, while a related belt of strong deep-layer southwesterly flow overspreads the Southwest. Boundary-layer mixing into this strong deep-layer flow will favor dry/breezy conditions across portions of western NM and eastern AZ during the afternoon. While this could lead to locally elevated fire-weather conditions, fuels are generally unsupportive of large-fire spread at this time. Elsewhere, a minimal overlap of breezy surface winds and low RH should limit fire-weather concerns. ..Weinman.. 09/19/2024 ...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 0121 AM CDT Thu Sep 19 2024 Valid 201200Z - 211200Z ...NO CRITICAL AREAS... ...Synopsis... A low-latitude midlevel low will advance eastward across the Lower CO River Valley, while a related belt of strong deep-layer southwesterly flow overspreads the Southwest. Boundary-layer mixing into this strong deep-layer flow will favor dry/breezy conditions across portions of western NM and eastern AZ during the afternoon. While this could lead to locally elevated fire-weather conditions, fuels are generally unsupportive of large-fire spread at this time. Elsewhere, a minimal overlap of breezy surface winds and low RH should limit fire-weather concerns. ..Weinman.. 09/19/2024 ...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 0121 AM CDT Thu Sep 19 2024 Valid 201200Z - 211200Z ...NO CRITICAL AREAS... ...Synopsis... A low-latitude midlevel low will advance eastward across the Lower CO River Valley, while a related belt of strong deep-layer southwesterly flow overspreads the Southwest. Boundary-layer mixing into this strong deep-layer flow will favor dry/breezy conditions across portions of western NM and eastern AZ during the afternoon. While this could lead to locally elevated fire-weather conditions, fuels are generally unsupportive of large-fire spread at this time. Elsewhere, a minimal overlap of breezy surface winds and low RH should limit fire-weather concerns. ..Weinman.. 09/19/2024 ...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 0120 AM CDT Thu Sep 19 2024 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... In the wake of a midlevel low tracking northeastward across Manitoba, strong post-frontal winds will overspread the northern Plains. While these winds may overlap pockets of 25-35 percent RH, cool surface temperatures/marginal RH and recent rainfall should limit the fire-weather threat. Elsewhere, an expansive surface high centered over the western CONUS will limit surface winds and the overall fire-weather risk. ..Weinman.. 09/19/2024 ...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 0120 AM CDT Thu Sep 19 2024 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... In the wake of a midlevel low tracking northeastward across Manitoba, strong post-frontal winds will overspread the northern Plains. While these winds may overlap pockets of 25-35 percent RH, cool surface temperatures/marginal RH and recent rainfall should limit the fire-weather threat. Elsewhere, an expansive surface high centered over the western CONUS will limit surface winds and the overall fire-weather risk. ..Weinman.. 09/19/2024 ...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 0120 AM CDT Thu Sep 19 2024 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... In the wake of a midlevel low tracking northeastward across Manitoba, strong post-frontal winds will overspread the northern Plains. While these winds may overlap pockets of 25-35 percent RH, cool surface temperatures/marginal RH and recent rainfall should limit the fire-weather threat. Elsewhere, an expansive surface high centered over the western CONUS will limit surface winds and the overall fire-weather risk. ..Weinman.. 09/19/2024 ...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 0120 AM CDT Thu Sep 19 2024 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... In the wake of a midlevel low tracking northeastward across Manitoba, strong post-frontal winds will overspread the northern Plains. While these winds may overlap pockets of 25-35 percent RH, cool surface temperatures/marginal RH and recent rainfall should limit the fire-weather threat. Elsewhere, an expansive surface high centered over the western CONUS will limit surface winds and the overall fire-weather risk. ..Weinman.. 09/19/2024 ...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 0120 AM CDT Thu Sep 19 2024 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... In the wake of a midlevel low tracking northeastward across Manitoba, strong post-frontal winds will overspread the northern Plains. While these winds may overlap pockets of 25-35 percent RH, cool surface temperatures/marginal RH and recent rainfall should limit the fire-weather threat. Elsewhere, an expansive surface high centered over the western CONUS will limit surface winds and the overall fire-weather risk. ..Weinman.. 09/19/2024 ...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 1249 AM CDT Thu Sep 19 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN A PART OF THE MIDWEST... ...SUMMARY... Isolated, marginally severe thunderstorms are possible in the late afternoon Friday in parts of Illinois, Indiana, and southwest Lower Michigan. ...Midwest... A low-amplitude shortwave trough will pass across the Upper to Central Great Lakes during the first half of the period. This will outpace a cold front that trails from a cyclone shifting northeast in MB, yielding a largely weakening to stalling front by Friday evening. Most guidance suggests at least isolated thunderstorms should form within a low-level warm conveyor ahead of the front, generally focused on a moderate buoyancy plume emanating northeast from parts of MO/AR. A fast westerly upper jet will further impinge on this portion of the front as well, favorably timed with peak boundary-layer heating. A few marginally severe storms may develop within this regime. Despite weak mid-level lapse rates, elongation of the mid to upper hodograph should support a threat for 1-1.5 inch hail, along with strong to marginally severe gusts from 45-60 mph. These threats should diminish quickly after sunset. ...Southern High Plains... Locally strong gusts are possible during the late afternoon to early evening with high-based, low-topped convection amid a weak buoyancy environment. The region will remain between a stout mid-level anticyclone over the Lower Rio Grande Valley and a southern-stream shortwave trough slowly moving across CA into AZ. Relatively warm mid-level temperatures should preclude appreciable storm intensity, but well-mixed boundary layers could support sporadic gusts approaching severe levels. ...Central Great Plains... Isolated elevated storms may develop overnight into Saturday morning within a strengthening warm theta-e advection regime. Weak mid-level lapse rates should temper elevated buoyancy and limit hail potential to some extent. But sufficient mid to upper-level speed shear could foster small hail production. ..Grams.. 09/19/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Thu Sep 19 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN A PART OF THE MIDWEST... ...SUMMARY... Isolated, marginally severe thunderstorms are possible in the late afternoon Friday in parts of Illinois, Indiana, and southwest Lower Michigan. ...Midwest... A low-amplitude shortwave trough will pass across the Upper to Central Great Lakes during the first half of the period. This will outpace a cold front that trails from a cyclone shifting northeast in MB, yielding a largely weakening to stalling front by Friday evening. Most guidance suggests at least isolated thunderstorms should form within a low-level warm conveyor ahead of the front, generally focused on a moderate buoyancy plume emanating northeast from parts of MO/AR. A fast westerly upper jet will further impinge on this portion of the front as well, favorably timed with peak boundary-layer heating. A few marginally severe storms may develop within this regime. Despite weak mid-level lapse rates, elongation of the mid to upper hodograph should support a threat for 1-1.5 inch hail, along with strong to marginally severe gusts from 45-60 mph. These threats should diminish quickly after sunset. ...Southern High Plains... Locally strong gusts are possible during the late afternoon to early evening with high-based, low-topped convection amid a weak buoyancy environment. The region will remain between a stout mid-level anticyclone over the Lower Rio Grande Valley and a southern-stream shortwave trough slowly moving across CA into AZ. Relatively warm mid-level temperatures should preclude appreciable storm intensity, but well-mixed boundary layers could support sporadic gusts approaching severe levels. ...Central Great Plains... Isolated elevated storms may develop overnight into Saturday morning within a strengthening warm theta-e advection regime. Weak mid-level lapse rates should temper elevated buoyancy and limit hail potential to some extent. But sufficient mid to upper-level speed shear could foster small hail production. ..Grams.. 09/19/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Thu Sep 19 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN A PART OF THE MIDWEST... ...SUMMARY... Isolated, marginally severe thunderstorms are possible in the late afternoon Friday in parts of Illinois, Indiana, and southwest Lower Michigan. ...Midwest... A low-amplitude shortwave trough will pass across the Upper to Central Great Lakes during the first half of the period. This will outpace a cold front that trails from a cyclone shifting northeast in MB, yielding a largely weakening to stalling front by Friday evening. Most guidance suggests at least isolated thunderstorms should form within a low-level warm conveyor ahead of the front, generally focused on a moderate buoyancy plume emanating northeast from parts of MO/AR. A fast westerly upper jet will further impinge on this portion of the front as well, favorably timed with peak boundary-layer heating. A few marginally severe storms may develop within this regime. Despite weak mid-level lapse rates, elongation of the mid to upper hodograph should support a threat for 1-1.5 inch hail, along with strong to marginally severe gusts from 45-60 mph. These threats should diminish quickly after sunset. ...Southern High Plains... Locally strong gusts are possible during the late afternoon to early evening with high-based, low-topped convection amid a weak buoyancy environment. The region will remain between a stout mid-level anticyclone over the Lower Rio Grande Valley and a southern-stream shortwave trough slowly moving across CA into AZ. Relatively warm mid-level temperatures should preclude appreciable storm intensity, but well-mixed boundary layers could support sporadic gusts approaching severe levels. ...Central Great Plains... Isolated elevated storms may develop overnight into Saturday morning within a strengthening warm theta-e advection regime. Weak mid-level lapse rates should temper elevated buoyancy and limit hail potential to some extent. But sufficient mid to upper-level speed shear could foster small hail production. ..Grams.. 09/19/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Thu Sep 19 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN A PART OF THE MIDWEST... ...SUMMARY... Isolated, marginally severe thunderstorms are possible in the late afternoon Friday in parts of Illinois, Indiana, and southwest Lower Michigan. ...Midwest... A low-amplitude shortwave trough will pass across the Upper to Central Great Lakes during the first half of the period. This will outpace a cold front that trails from a cyclone shifting northeast in MB, yielding a largely weakening to stalling front by Friday evening. Most guidance suggests at least isolated thunderstorms should form within a low-level warm conveyor ahead of the front, generally focused on a moderate buoyancy plume emanating northeast from parts of MO/AR. A fast westerly upper jet will further impinge on this portion of the front as well, favorably timed with peak boundary-layer heating. A few marginally severe storms may develop within this regime. Despite weak mid-level lapse rates, elongation of the mid to upper hodograph should support a threat for 1-1.5 inch hail, along with strong to marginally severe gusts from 45-60 mph. These threats should diminish quickly after sunset. ...Southern High Plains... Locally strong gusts are possible during the late afternoon to early evening with high-based, low-topped convection amid a weak buoyancy environment. The region will remain between a stout mid-level anticyclone over the Lower Rio Grande Valley and a southern-stream shortwave trough slowly moving across CA into AZ. Relatively warm mid-level temperatures should preclude appreciable storm intensity, but well-mixed boundary layers could support sporadic gusts approaching severe levels. ...Central Great Plains... Isolated elevated storms may develop overnight into Saturday morning within a strengthening warm theta-e advection regime. Weak mid-level lapse rates should temper elevated buoyancy and limit hail potential to some extent. But sufficient mid to upper-level speed shear could foster small hail production. ..Grams.. 09/19/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Thu Sep 19 2024 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN A PART OF THE MIDWEST... ...SUMMARY... Isolated, marginally severe thunderstorms are possible in the late afternoon Friday in parts of Illinois, Indiana, and southwest Lower Michigan. ...Midwest... A low-amplitude shortwave trough will pass across the Upper to Central Great Lakes during the first half of the period. This will outpace a cold front that trails from a cyclone shifting northeast in MB, yielding a largely weakening to stalling front by Friday evening. Most guidance suggests at least isolated thunderstorms should form within a low-level warm conveyor ahead of the front, generally focused on a moderate buoyancy plume emanating northeast from parts of MO/AR. A fast westerly upper jet will further impinge on this portion of the front as well, favorably timed with peak boundary-layer heating. A few marginally severe storms may develop within this regime. Despite weak mid-level lapse rates, elongation of the mid to upper hodograph should support a threat for 1-1.5 inch hail, along with strong to marginally severe gusts from 45-60 mph. These threats should diminish quickly after sunset. ...Southern High Plains... Locally strong gusts are possible during the late afternoon to early evening with high-based, low-topped convection amid a weak buoyancy environment. The region will remain between a stout mid-level anticyclone over the Lower Rio Grande Valley and a southern-stream shortwave trough slowly moving across CA into AZ. Relatively warm mid-level temperatures should preclude appreciable storm intensity, but well-mixed boundary layers could support sporadic gusts approaching severe levels. ...Central Great Plains... Isolated elevated storms may develop overnight into Saturday morning within a strengthening warm theta-e advection regime. Weak mid-level lapse rates should temper elevated buoyancy and limit hail potential to some extent. But sufficient mid to upper-level speed shear could foster small hail production. ..Grams.. 09/19/2024 Read more

000
ABPZ20 KNHC 190549
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Wed Sep 18 2024

For the eastern North Pacific...east of 140 degrees west longitude:

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Papin

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1229 AM CDT Thu Sep 19 2024 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM MINNESOTA...IOWA AND WESTERN WISCONSIN SOUTHWARD INTO EASTERN KANSAS AND WESTERN MISSOURI... ...SUMMARY... Scattered severe thunderstorms are possible across central/eastern Minnesota, Iowa, and western Wisconsin. A couple tornadoes, isolated large hail, and damaging winds may occur. An area of locally severe gusts and hail may also develop over parts of eastern Kansas, southwest Missouri, and into northeast Oklahoma. ...Synopsis... A negatively tilted shortwave trough will move across the Dakotas and MN during the day, with veering midlevel winds into western MN by late afternoon. Farther south, moderate west/southwest winds in the midlevels will extend into NE and IA, with weaker west to northwest winds around a southern Plains upper high from KS/OK into MO and AR. In the high levels, flow will be strongest across the central Plains, with weakening winds over the northern Plains/upper MS Valley. At the surface, the primary low will move into southern MB, with a cold front moving into MN and western IA by mid afternoon. A wind shift/surface trough will also extend southward across eastern KS and into northern OK at that time. Southerly surface winds will set up a plume of mid to upper 60s F dewpoints east of the front/surface trough, and this will aid moderate destabilization across the length of the front, with scattered severe storms from MN to perhaps OK. ...Upper MS Valley... Scattered early day elevated storms are likely to dissipate by midday as they move out of MN/IA into WI, with destabilization in their wake. Strong heating near the surface trough/front along with cool temperatures aloft will yield MUCAPE to around 3000 J/kg, beneath 35-40 kt 500 mb winds. A broken line of storms including supercells are expected after 21Z over much of central and eastern MN and into IA. A couple tornadoes are most likely from IA into southern MN and southwest WI where effective SRH may exceed 200 m2/s2. Given the northward lifting of the shortwave trough, and increasing inhibition east of the MS River, the primary threat are may remain relatively narrow. ...Eastern KS into western MO and into OK... A few thunderstorms may be ongoing early this morning from IA into northwest MO, near the 850 mb theta-e plume and beneath subtle height falls. A cell or two may persist into the afternoon, likely translating southeastward across western MO. A greater risk of locally severe wind gusts or hail will then develop near and just west of the early day activity, as a plume of steep lapse rates develops out of OK into KS. While midlevel subsidence may limit instability somewhat, plenty of CAPE will be present at or above 2000 J/kg, with a lengthy mid to upper level hodograph by virtue of northwest flow aloft. As such, hail may still occur with the cellular storm modes, and favorable time of day and hot surface conditions will favor locally strong to damaging gusts. ..Jewell/Weinman.. 09/19/2024 Read more