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MD 1583 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHEAST KANSAS...SOUTHWEST MISSOURI...FAR NORTHEAST OKLAHOMA
Mesoscale Discussion 1583 NWS Storm Prediction Center Norman OK 0138 AM CDT Fri Jul 12 2024 Areas affected...Southeast Kansas...Southwest Missouri...Far Northeast Oklahoma Concerning...Severe potential...Watch unlikely Valid 120638Z - 120845Z Probability of Watch Issuance...20 percent SUMMARY...A threat for isolated large hail will likely continue for a few more hours from southeast Kansas into southwest Missouri and far northeast Oklahoma. The convective cluster is expected to remain too disorganized for watch issuance. DISCUSSION...Over the last couple of hours, scattered thunderstorms have developed across southeast Kansas, with embedded pulse hail events. This activity is located along the eastern edge of a pocket of moderate instability, where the RAP has MLCAPE in the 2000 to 2500 J/kg range. The storms appear to be supported by a strengthening low-level jet, that is in the 30 to 35 knot range according the RAP. As this feature continues, thunderstorm development will likely persist. In addition, RAP forecast soundings in far southeast Kansas have 850 to 500 mb lapse rates near 7 C/km, and enough deep-layer shear for an isolated large-hail threat. The hail threat is expected continue for a few more hours, before the storm complex gradually diminishes. ..Broyles/Edwards.. 07/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGF...EAX...TSA...TOP...ICT... LAT...LON 37739560 36849546 36519515 36439466 36529416 36789381 37349366 37869369 38329393 38539429 38579466 38549506 38399536 38139555 37739560 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0224 AM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z ...Synopsis... Fire weather concerns will continue into the weekend across the western U.S. - especially across the Great Basin where isolated to scattered dry thunderstorms are expected to develop by mid-afternoon and persist into the overnight hours. Continued hot/dry conditions are expected across much of the West, with breezy winds likely across portions of the Pacific Northwest and northern Rockies on the northern periphery of a dominant upper ridge centered over the southern Great Basin. ...Dry Thunderstorms - Sierra Nevada and the Great Basin... A weak mid-level low is noted in early-morning water-vapor imagery off the CA coast to the west of a more dominant upper ridge. Concurrently, a plume of 0.5-0.9 inch PWAT values is slowly migrating northward from southern/central CA. This moisture will continue to spread north over the next 48 hours and will phase with the mid-level impulse as it moves north Saturday afternoon/overnight. The combination of increasing mid-level moisture atop very dry boundary-layer conditions - along with 20-25 knot mean storm motions - will support the potential for dry thunderstorms. Forecast guidance suggests thunderstorms will initially develop across the southern Sierra Nevada into the lower CO River Valley Saturday afternoon around peak heating, slowly spreading north during the evening and overnight hours. Ensemble guidance currently depicts low (30% or lower) probability for wetting rainfall, and recent fuel guidance indicates that lightning-ignition efficiency is fairly high (15-20%) along the Sierra Nevada and into central NV/southern OR/ID. Consequently, dry lightning concerns are likely, and an upgrade to Scattered Dry Thunderstorms may be warranted if a corridor of higher thunderstorm potential becomes apparent in high-res guidance. ...Pacific Northwest/northwest Nevada and ID/MT... Hot/dry conditions are expected to continue across the Pacific Northwest with another day of RH values in the single digits to low teens. A belt of strong mid-level flow should reside across the Cascades/northern Sierra Nevada into the northern Rockies, which will maintain lee troughing across eastern OR/WA and across the northern High Plains. A combination of modest gradient winds, downslope wind enhancement, and deep boundary-layer mixing should yield areas of 15-20 mph winds coincident with very dry conditions. Elevated fire weather conditions appear likely with localized critical conditions possible. ..Moore.. 07/12/2024 ...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 0224 AM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z ...Synopsis... Fire weather concerns will continue into the weekend across the western U.S. - especially across the Great Basin where isolated to scattered dry thunderstorms are expected to develop by mid-afternoon and persist into the overnight hours. Continued hot/dry conditions are expected across much of the West, with breezy winds likely across portions of the Pacific Northwest and northern Rockies on the northern periphery of a dominant upper ridge centered over the southern Great Basin. ...Dry Thunderstorms - Sierra Nevada and the Great Basin... A weak mid-level low is noted in early-morning water-vapor imagery off the CA coast to the west of a more dominant upper ridge. Concurrently, a plume of 0.5-0.9 inch PWAT values is slowly migrating northward from southern/central CA. This moisture will continue to spread north over the next 48 hours and will phase with the mid-level impulse as it moves north Saturday afternoon/overnight. The combination of increasing mid-level moisture atop very dry boundary-layer conditions - along with 20-25 knot mean storm motions - will support the potential for dry thunderstorms. Forecast guidance suggests thunderstorms will initially develop across the southern Sierra Nevada into the lower CO River Valley Saturday afternoon around peak heating, slowly spreading north during the evening and overnight hours. Ensemble guidance currently depicts low (30% or lower) probability for wetting rainfall, and recent fuel guidance indicates that lightning-ignition efficiency is fairly high (15-20%) along the Sierra Nevada and into central NV/southern OR/ID. Consequently, dry lightning concerns are likely, and an upgrade to Scattered Dry Thunderstorms may be warranted if a corridor of higher thunderstorm potential becomes apparent in high-res guidance. ...Pacific Northwest/northwest Nevada and ID/MT... Hot/dry conditions are expected to continue across the Pacific Northwest with another day of RH values in the single digits to low teens. A belt of strong mid-level flow should reside across the Cascades/northern Sierra Nevada into the northern Rockies, which will maintain lee troughing across eastern OR/WA and across the northern High Plains. A combination of modest gradient winds, downslope wind enhancement, and deep boundary-layer mixing should yield areas of 15-20 mph winds coincident with very dry conditions. Elevated fire weather conditions appear likely with localized critical conditions possible. ..Moore.. 07/12/2024 ...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 0224 AM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z ...Synopsis... Fire weather concerns will continue into the weekend across the western U.S. - especially across the Great Basin where isolated to scattered dry thunderstorms are expected to develop by mid-afternoon and persist into the overnight hours. Continued hot/dry conditions are expected across much of the West, with breezy winds likely across portions of the Pacific Northwest and northern Rockies on the northern periphery of a dominant upper ridge centered over the southern Great Basin. ...Dry Thunderstorms - Sierra Nevada and the Great Basin... A weak mid-level low is noted in early-morning water-vapor imagery off the CA coast to the west of a more dominant upper ridge. Concurrently, a plume of 0.5-0.9 inch PWAT values is slowly migrating northward from southern/central CA. This moisture will continue to spread north over the next 48 hours and will phase with the mid-level impulse as it moves north Saturday afternoon/overnight. The combination of increasing mid-level moisture atop very dry boundary-layer conditions - along with 20-25 knot mean storm motions - will support the potential for dry thunderstorms. Forecast guidance suggests thunderstorms will initially develop across the southern Sierra Nevada into the lower CO River Valley Saturday afternoon around peak heating, slowly spreading north during the evening and overnight hours. Ensemble guidance currently depicts low (30% or lower) probability for wetting rainfall, and recent fuel guidance indicates that lightning-ignition efficiency is fairly high (15-20%) along the Sierra Nevada and into central NV/southern OR/ID. Consequently, dry lightning concerns are likely, and an upgrade to Scattered Dry Thunderstorms may be warranted if a corridor of higher thunderstorm potential becomes apparent in high-res guidance. ...Pacific Northwest/northwest Nevada and ID/MT... Hot/dry conditions are expected to continue across the Pacific Northwest with another day of RH values in the single digits to low teens. A belt of strong mid-level flow should reside across the Cascades/northern Sierra Nevada into the northern Rockies, which will maintain lee troughing across eastern OR/WA and across the northern High Plains. A combination of modest gradient winds, downslope wind enhancement, and deep boundary-layer mixing should yield areas of 15-20 mph winds coincident with very dry conditions. Elevated fire weather conditions appear likely with localized critical conditions possible. ..Moore.. 07/12/2024 ...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 0224 AM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z ...Synopsis... Fire weather concerns will continue into the weekend across the western U.S. - especially across the Great Basin where isolated to scattered dry thunderstorms are expected to develop by mid-afternoon and persist into the overnight hours. Continued hot/dry conditions are expected across much of the West, with breezy winds likely across portions of the Pacific Northwest and northern Rockies on the northern periphery of a dominant upper ridge centered over the southern Great Basin. ...Dry Thunderstorms - Sierra Nevada and the Great Basin... A weak mid-level low is noted in early-morning water-vapor imagery off the CA coast to the west of a more dominant upper ridge. Concurrently, a plume of 0.5-0.9 inch PWAT values is slowly migrating northward from southern/central CA. This moisture will continue to spread north over the next 48 hours and will phase with the mid-level impulse as it moves north Saturday afternoon/overnight. The combination of increasing mid-level moisture atop very dry boundary-layer conditions - along with 20-25 knot mean storm motions - will support the potential for dry thunderstorms. Forecast guidance suggests thunderstorms will initially develop across the southern Sierra Nevada into the lower CO River Valley Saturday afternoon around peak heating, slowly spreading north during the evening and overnight hours. Ensemble guidance currently depicts low (30% or lower) probability for wetting rainfall, and recent fuel guidance indicates that lightning-ignition efficiency is fairly high (15-20%) along the Sierra Nevada and into central NV/southern OR/ID. Consequently, dry lightning concerns are likely, and an upgrade to Scattered Dry Thunderstorms may be warranted if a corridor of higher thunderstorm potential becomes apparent in high-res guidance. ...Pacific Northwest/northwest Nevada and ID/MT... Hot/dry conditions are expected to continue across the Pacific Northwest with another day of RH values in the single digits to low teens. A belt of strong mid-level flow should reside across the Cascades/northern Sierra Nevada into the northern Rockies, which will maintain lee troughing across eastern OR/WA and across the northern High Plains. A combination of modest gradient winds, downslope wind enhancement, and deep boundary-layer mixing should yield areas of 15-20 mph winds coincident with very dry conditions. Elevated fire weather conditions appear likely with localized critical conditions possible. ..Moore.. 07/12/2024 ...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 0224 AM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z ...Synopsis... Fire weather concerns will continue into the weekend across the western U.S. - especially across the Great Basin where isolated to scattered dry thunderstorms are expected to develop by mid-afternoon and persist into the overnight hours. Continued hot/dry conditions are expected across much of the West, with breezy winds likely across portions of the Pacific Northwest and northern Rockies on the northern periphery of a dominant upper ridge centered over the southern Great Basin. ...Dry Thunderstorms - Sierra Nevada and the Great Basin... A weak mid-level low is noted in early-morning water-vapor imagery off the CA coast to the west of a more dominant upper ridge. Concurrently, a plume of 0.5-0.9 inch PWAT values is slowly migrating northward from southern/central CA. This moisture will continue to spread north over the next 48 hours and will phase with the mid-level impulse as it moves north Saturday afternoon/overnight. The combination of increasing mid-level moisture atop very dry boundary-layer conditions - along with 20-25 knot mean storm motions - will support the potential for dry thunderstorms. Forecast guidance suggests thunderstorms will initially develop across the southern Sierra Nevada into the lower CO River Valley Saturday afternoon around peak heating, slowly spreading north during the evening and overnight hours. Ensemble guidance currently depicts low (30% or lower) probability for wetting rainfall, and recent fuel guidance indicates that lightning-ignition efficiency is fairly high (15-20%) along the Sierra Nevada and into central NV/southern OR/ID. Consequently, dry lightning concerns are likely, and an upgrade to Scattered Dry Thunderstorms may be warranted if a corridor of higher thunderstorm potential becomes apparent in high-res guidance. ...Pacific Northwest/northwest Nevada and ID/MT... Hot/dry conditions are expected to continue across the Pacific Northwest with another day of RH values in the single digits to low teens. A belt of strong mid-level flow should reside across the Cascades/northern Sierra Nevada into the northern Rockies, which will maintain lee troughing across eastern OR/WA and across the northern High Plains. A combination of modest gradient winds, downslope wind enhancement, and deep boundary-layer mixing should yield areas of 15-20 mph winds coincident with very dry conditions. Elevated fire weather conditions appear likely with localized critical conditions possible. ..Moore.. 07/12/2024 ...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 0220 AM CDT Fri Jul 12 2024 Valid 121200Z - 131200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEAST OREGON... ...Synopsis... Fire weather concerns will continue today across portions of the greater Great Basin region. Another day of very hot/dry conditions is expected today as afternoon highs across much of the West climb above 100 F. As of 05 UTC, single-digit RH values were noted across much of the region with little, if any, improvement in surface relative humidity anticipated over the next 24 hours. Despite the hot/dry conditions, an upper ridge centered over southern NV will continue to promote relatively benign winds for most locations, with the exception of the northern Great Basin where gradient winds on the periphery of the ridge will be slightly stronger. Isolated dry thunderstorms will also pose a fire weather concern across parts of the lower CO River Valley and along the Sierra Nevada. ...Southeast OR into southern WY... A low-amplitude mid-level impulse is noted in early-morning water-vapor imagery approaching the Pacific Northwest. Stronger mid-level flow associated with this feature should overspread the Cascades and northern Rockies through the day, leading to modest surface pressure falls across eastern OR/WA into western ID as well as along the northern High Plains. Low-level winds should strengthen to between 15-20 mph within a belt stretching from southern OR into southern ID and southern WY. Active fire behavior over the past 24 hours across east-central OR (even the absence of substantial winds) suggests that fuels are very receptive to fire spread, so the combination of very dry and breezy conditions will support elevated to critical fire weather. A Critical risk area has been introduced for portions of southeast OR into adjacent areas of northwest NV and far northeast CA where ensemble guidance shows a reasonably strong signal (70% probability in latest HREF and NBM guidance) for sustained winds between 20-25 mph and the potential for gusts up to 35 mph. ...Lower CO River Valley into the Sierra Nevada... 00 UTC soundings sampled a plume of 0.5-0.9 inch precipitable water values across the Four Corners region into southern CA. Recent GOES imagery shows this plume gradually migrating west/northwestward along the southern/southwestern side of the upper ridge. Steep mid-level lapse rates across the region coupled with deep boundary-layer mixing should support meager, but sufficient, buoyancy for convection. Thunderstorm coverage should be fairly isolated and tied to terrain features, as orographic ascent drives thunderstorm development around peak heating. However, dry lightning appears probable with any convection that can develop given the very dry low-level conditions, and should pose a fire weather concern given antecedent dry fuels. ..Moore.. 07/12/2024 ...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 0220 AM CDT Fri Jul 12 2024 Valid 121200Z - 131200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEAST OREGON... ...Synopsis... Fire weather concerns will continue today across portions of the greater Great Basin region. Another day of very hot/dry conditions is expected today as afternoon highs across much of the West climb above 100 F. As of 05 UTC, single-digit RH values were noted across much of the region with little, if any, improvement in surface relative humidity anticipated over the next 24 hours. Despite the hot/dry conditions, an upper ridge centered over southern NV will continue to promote relatively benign winds for most locations, with the exception of the northern Great Basin where gradient winds on the periphery of the ridge will be slightly stronger. Isolated dry thunderstorms will also pose a fire weather concern across parts of the lower CO River Valley and along the Sierra Nevada. ...Southeast OR into southern WY... A low-amplitude mid-level impulse is noted in early-morning water-vapor imagery approaching the Pacific Northwest. Stronger mid-level flow associated with this feature should overspread the Cascades and northern Rockies through the day, leading to modest surface pressure falls across eastern OR/WA into western ID as well as along the northern High Plains. Low-level winds should strengthen to between 15-20 mph within a belt stretching from southern OR into southern ID and southern WY. Active fire behavior over the past 24 hours across east-central OR (even the absence of substantial winds) suggests that fuels are very receptive to fire spread, so the combination of very dry and breezy conditions will support elevated to critical fire weather. A Critical risk area has been introduced for portions of southeast OR into adjacent areas of northwest NV and far northeast CA where ensemble guidance shows a reasonably strong signal (70% probability in latest HREF and NBM guidance) for sustained winds between 20-25 mph and the potential for gusts up to 35 mph. ...Lower CO River Valley into the Sierra Nevada... 00 UTC soundings sampled a plume of 0.5-0.9 inch precipitable water values across the Four Corners region into southern CA. Recent GOES imagery shows this plume gradually migrating west/northwestward along the southern/southwestern side of the upper ridge. Steep mid-level lapse rates across the region coupled with deep boundary-layer mixing should support meager, but sufficient, buoyancy for convection. Thunderstorm coverage should be fairly isolated and tied to terrain features, as orographic ascent drives thunderstorm development around peak heating. However, dry lightning appears probable with any convection that can develop given the very dry low-level conditions, and should pose a fire weather concern given antecedent dry fuels. ..Moore.. 07/12/2024 ...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 0220 AM CDT Fri Jul 12 2024 Valid 121200Z - 131200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEAST OREGON... ...Synopsis... Fire weather concerns will continue today across portions of the greater Great Basin region. Another day of very hot/dry conditions is expected today as afternoon highs across much of the West climb above 100 F. As of 05 UTC, single-digit RH values were noted across much of the region with little, if any, improvement in surface relative humidity anticipated over the next 24 hours. Despite the hot/dry conditions, an upper ridge centered over southern NV will continue to promote relatively benign winds for most locations, with the exception of the northern Great Basin where gradient winds on the periphery of the ridge will be slightly stronger. Isolated dry thunderstorms will also pose a fire weather concern across parts of the lower CO River Valley and along the Sierra Nevada. ...Southeast OR into southern WY... A low-amplitude mid-level impulse is noted in early-morning water-vapor imagery approaching the Pacific Northwest. Stronger mid-level flow associated with this feature should overspread the Cascades and northern Rockies through the day, leading to modest surface pressure falls across eastern OR/WA into western ID as well as along the northern High Plains. Low-level winds should strengthen to between 15-20 mph within a belt stretching from southern OR into southern ID and southern WY. Active fire behavior over the past 24 hours across east-central OR (even the absence of substantial winds) suggests that fuels are very receptive to fire spread, so the combination of very dry and breezy conditions will support elevated to critical fire weather. A Critical risk area has been introduced for portions of southeast OR into adjacent areas of northwest NV and far northeast CA where ensemble guidance shows a reasonably strong signal (70% probability in latest HREF and NBM guidance) for sustained winds between 20-25 mph and the potential for gusts up to 35 mph. ...Lower CO River Valley into the Sierra Nevada... 00 UTC soundings sampled a plume of 0.5-0.9 inch precipitable water values across the Four Corners region into southern CA. Recent GOES imagery shows this plume gradually migrating west/northwestward along the southern/southwestern side of the upper ridge. Steep mid-level lapse rates across the region coupled with deep boundary-layer mixing should support meager, but sufficient, buoyancy for convection. Thunderstorm coverage should be fairly isolated and tied to terrain features, as orographic ascent drives thunderstorm development around peak heating. However, dry lightning appears probable with any convection that can develop given the very dry low-level conditions, and should pose a fire weather concern given antecedent dry fuels. ..Moore.. 07/12/2024 ...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 0220 AM CDT Fri Jul 12 2024 Valid 121200Z - 131200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEAST OREGON... ...Synopsis... Fire weather concerns will continue today across portions of the greater Great Basin region. Another day of very hot/dry conditions is expected today as afternoon highs across much of the West climb above 100 F. As of 05 UTC, single-digit RH values were noted across much of the region with little, if any, improvement in surface relative humidity anticipated over the next 24 hours. Despite the hot/dry conditions, an upper ridge centered over southern NV will continue to promote relatively benign winds for most locations, with the exception of the northern Great Basin where gradient winds on the periphery of the ridge will be slightly stronger. Isolated dry thunderstorms will also pose a fire weather concern across parts of the lower CO River Valley and along the Sierra Nevada. ...Southeast OR into southern WY... A low-amplitude mid-level impulse is noted in early-morning water-vapor imagery approaching the Pacific Northwest. Stronger mid-level flow associated with this feature should overspread the Cascades and northern Rockies through the day, leading to modest surface pressure falls across eastern OR/WA into western ID as well as along the northern High Plains. Low-level winds should strengthen to between 15-20 mph within a belt stretching from southern OR into southern ID and southern WY. Active fire behavior over the past 24 hours across east-central OR (even the absence of substantial winds) suggests that fuels are very receptive to fire spread, so the combination of very dry and breezy conditions will support elevated to critical fire weather. A Critical risk area has been introduced for portions of southeast OR into adjacent areas of northwest NV and far northeast CA where ensemble guidance shows a reasonably strong signal (70% probability in latest HREF and NBM guidance) for sustained winds between 20-25 mph and the potential for gusts up to 35 mph. ...Lower CO River Valley into the Sierra Nevada... 00 UTC soundings sampled a plume of 0.5-0.9 inch precipitable water values across the Four Corners region into southern CA. Recent GOES imagery shows this plume gradually migrating west/northwestward along the southern/southwestern side of the upper ridge. Steep mid-level lapse rates across the region coupled with deep boundary-layer mixing should support meager, but sufficient, buoyancy for convection. Thunderstorm coverage should be fairly isolated and tied to terrain features, as orographic ascent drives thunderstorm development around peak heating. However, dry lightning appears probable with any convection that can develop given the very dry low-level conditions, and should pose a fire weather concern given antecedent dry fuels. ..Moore.. 07/12/2024 ...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 0220 AM CDT Fri Jul 12 2024 Valid 121200Z - 131200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEAST OREGON... ...Synopsis... Fire weather concerns will continue today across portions of the greater Great Basin region. Another day of very hot/dry conditions is expected today as afternoon highs across much of the West climb above 100 F. As of 05 UTC, single-digit RH values were noted across much of the region with little, if any, improvement in surface relative humidity anticipated over the next 24 hours. Despite the hot/dry conditions, an upper ridge centered over southern NV will continue to promote relatively benign winds for most locations, with the exception of the northern Great Basin where gradient winds on the periphery of the ridge will be slightly stronger. Isolated dry thunderstorms will also pose a fire weather concern across parts of the lower CO River Valley and along the Sierra Nevada. ...Southeast OR into southern WY... A low-amplitude mid-level impulse is noted in early-morning water-vapor imagery approaching the Pacific Northwest. Stronger mid-level flow associated with this feature should overspread the Cascades and northern Rockies through the day, leading to modest surface pressure falls across eastern OR/WA into western ID as well as along the northern High Plains. Low-level winds should strengthen to between 15-20 mph within a belt stretching from southern OR into southern ID and southern WY. Active fire behavior over the past 24 hours across east-central OR (even the absence of substantial winds) suggests that fuels are very receptive to fire spread, so the combination of very dry and breezy conditions will support elevated to critical fire weather. A Critical risk area has been introduced for portions of southeast OR into adjacent areas of northwest NV and far northeast CA where ensemble guidance shows a reasonably strong signal (70% probability in latest HREF and NBM guidance) for sustained winds between 20-25 mph and the potential for gusts up to 35 mph. ...Lower CO River Valley into the Sierra Nevada... 00 UTC soundings sampled a plume of 0.5-0.9 inch precipitable water values across the Four Corners region into southern CA. Recent GOES imagery shows this plume gradually migrating west/northwestward along the southern/southwestern side of the upper ridge. Steep mid-level lapse rates across the region coupled with deep boundary-layer mixing should support meager, but sufficient, buoyancy for convection. Thunderstorm coverage should be fairly isolated and tied to terrain features, as orographic ascent drives thunderstorm development around peak heating. However, dry lightning appears probable with any convection that can develop given the very dry low-level conditions, and should pose a fire weather concern given antecedent dry fuels. ..Moore.. 07/12/2024 ...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 0100 AM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN PLAINS INTO THE UPPER MIDWEST... ...SUMMARY... Multiple clusters of strong to severe thunderstorms are possible across portions of the Northern Plains into the Upper Mississippi Valley on Saturday. ...Synopsis... Upper ridging is forecast to be centered over the Four Corners early Saturday morning, remaining largely in place for the remainder of the period. An upper trough is expected to progress through north-central Canada, contributing to moderate westerly mid-level flow between this trough and the Four Corners ridging. A shortwave trough will likely move through this westerly flow, progressing across the northern Plains/southern Canadian Prairie Provinces into the Upper Midwest. Primary surface low associated with this wave will likely move just ahead of it from central Manitoba into far northwestern Ontario. A secondary surface low may develop at the triple point, with this low likely moving from central ND eastward across northern MN. Farther east, a shortwave trough is forecast to progress eastward from southern Quebec/western NY across the Northeast while subtropical ridging persists over the Southeast. ...Eastern Dakotas into the Upper Midwest... A very moist airmass will likely be in place from the eastern Dakotas into the Upper Midwest on Saturday morning, preceding the shortwave trough and associated surface features mentioned in the synopsis. Some isolated thunderstorms may be ongoing across MN early Saturday morning, supported by warm-air advection throughout the warm sector. Evolution of this early morning convection is uncertain, but it will likely shift gradually southeastward throughout the morning, potentially persisting long enough to become surface-based in the northeast IA/southern WI/northern IL vicinity. If this scenario is realized, the primary severe threat would be damaging gusts. Afternoon thunderstorm development also appears probable across western MN as the surface low interacts with the warm and moist airmass expected to be in place. Surface temperatures in the mid to upper 80s/low 90s amid upper 60s/low 70 dewpoints will support strong to very strong buoyancy, with MLCAPE over 3000 J/kg probable. Moderate vertical shear is anticipated across the region, but precipitation-laden updrafts are still expected to promote a predominantly outflow-dominant storm mode. Some outflow amalgamation is possible, with the resulting convective line then progressing southeastward into west-central WI. Primary severe threat is damaging gusts, but isolated large hail is possible with early cellular development. Outflow-dominant storm mode should keep the tornado threat low, but more southerly flow is possible near the surface low, with surface vorticity greater in this region as well. This could result in some low-probability tornado potential. ...Northeast MT into northern ND... Combination of low-level convergence along the lee trough and moderate low-level moisture (likely via post-frontal upslope flow) may result in convective initiation over northeast MT. Easterly low-level flow veering to westerly aloft will support strong vertical shear capable of maintaining a supercellular storm mode. Large hail and/or damaging gusts are the primary risks with these storms as the move eastward into northwest/northern ND. ...Western/Central SD and the NE Panhandle... Isolated thunderstorm development is possible Saturday afternoon amid the low-level convergence across western SD and the NE Panhandle. High cloud bases and moderate northwesterly flow aloft could support a few strong downbursts with any more robust convection. ...Lower MO Valley/Ozark Plateau into the Lower OH Valley... Thunderstorms may be ongoing over the Lower MO Valley/Ozark Plateau early Saturday morning, supported by warm-air advection associated with the low-level jet. These storms will likely be sub-severe, but an associated convectively induced vorticity maximum may drift eastward throughout the day, leading to additional storm development during the afternoon across the Lower OH Valley. Current expectation is that modest vertical shear should limit the severe potential within these storms. ..Mosier.. 07/12/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN PLAINS INTO THE UPPER MIDWEST... ...SUMMARY... Multiple clusters of strong to severe thunderstorms are possible across portions of the Northern Plains into the Upper Mississippi Valley on Saturday. ...Synopsis... Upper ridging is forecast to be centered over the Four Corners early Saturday morning, remaining largely in place for the remainder of the period. An upper trough is expected to progress through north-central Canada, contributing to moderate westerly mid-level flow between this trough and the Four Corners ridging. A shortwave trough will likely move through this westerly flow, progressing across the northern Plains/southern Canadian Prairie Provinces into the Upper Midwest. Primary surface low associated with this wave will likely move just ahead of it from central Manitoba into far northwestern Ontario. A secondary surface low may develop at the triple point, with this low likely moving from central ND eastward across northern MN. Farther east, a shortwave trough is forecast to progress eastward from southern Quebec/western NY across the Northeast while subtropical ridging persists over the Southeast. ...Eastern Dakotas into the Upper Midwest... A very moist airmass will likely be in place from the eastern Dakotas into the Upper Midwest on Saturday morning, preceding the shortwave trough and associated surface features mentioned in the synopsis. Some isolated thunderstorms may be ongoing across MN early Saturday morning, supported by warm-air advection throughout the warm sector. Evolution of this early morning convection is uncertain, but it will likely shift gradually southeastward throughout the morning, potentially persisting long enough to become surface-based in the northeast IA/southern WI/northern IL vicinity. If this scenario is realized, the primary severe threat would be damaging gusts. Afternoon thunderstorm development also appears probable across western MN as the surface low interacts with the warm and moist airmass expected to be in place. Surface temperatures in the mid to upper 80s/low 90s amid upper 60s/low 70 dewpoints will support strong to very strong buoyancy, with MLCAPE over 3000 J/kg probable. Moderate vertical shear is anticipated across the region, but precipitation-laden updrafts are still expected to promote a predominantly outflow-dominant storm mode. Some outflow amalgamation is possible, with the resulting convective line then progressing southeastward into west-central WI. Primary severe threat is damaging gusts, but isolated large hail is possible with early cellular development. Outflow-dominant storm mode should keep the tornado threat low, but more southerly flow is possible near the surface low, with surface vorticity greater in this region as well. This could result in some low-probability tornado potential. ...Northeast MT into northern ND... Combination of low-level convergence along the lee trough and moderate low-level moisture (likely via post-frontal upslope flow) may result in convective initiation over northeast MT. Easterly low-level flow veering to westerly aloft will support strong vertical shear capable of maintaining a supercellular storm mode. Large hail and/or damaging gusts are the primary risks with these storms as the move eastward into northwest/northern ND. ...Western/Central SD and the NE Panhandle... Isolated thunderstorm development is possible Saturday afternoon amid the low-level convergence across western SD and the NE Panhandle. High cloud bases and moderate northwesterly flow aloft could support a few strong downbursts with any more robust convection. ...Lower MO Valley/Ozark Plateau into the Lower OH Valley... Thunderstorms may be ongoing over the Lower MO Valley/Ozark Plateau early Saturday morning, supported by warm-air advection associated with the low-level jet. These storms will likely be sub-severe, but an associated convectively induced vorticity maximum may drift eastward throughout the day, leading to additional storm development during the afternoon across the Lower OH Valley. Current expectation is that modest vertical shear should limit the severe potential within these storms. ..Mosier.. 07/12/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN PLAINS INTO THE UPPER MIDWEST... ...SUMMARY... Multiple clusters of strong to severe thunderstorms are possible across portions of the Northern Plains into the Upper Mississippi Valley on Saturday. ...Synopsis... Upper ridging is forecast to be centered over the Four Corners early Saturday morning, remaining largely in place for the remainder of the period. An upper trough is expected to progress through north-central Canada, contributing to moderate westerly mid-level flow between this trough and the Four Corners ridging. A shortwave trough will likely move through this westerly flow, progressing across the northern Plains/southern Canadian Prairie Provinces into the Upper Midwest. Primary surface low associated with this wave will likely move just ahead of it from central Manitoba into far northwestern Ontario. A secondary surface low may develop at the triple point, with this low likely moving from central ND eastward across northern MN. Farther east, a shortwave trough is forecast to progress eastward from southern Quebec/western NY across the Northeast while subtropical ridging persists over the Southeast. ...Eastern Dakotas into the Upper Midwest... A very moist airmass will likely be in place from the eastern Dakotas into the Upper Midwest on Saturday morning, preceding the shortwave trough and associated surface features mentioned in the synopsis. Some isolated thunderstorms may be ongoing across MN early Saturday morning, supported by warm-air advection throughout the warm sector. Evolution of this early morning convection is uncertain, but it will likely shift gradually southeastward throughout the morning, potentially persisting long enough to become surface-based in the northeast IA/southern WI/northern IL vicinity. If this scenario is realized, the primary severe threat would be damaging gusts. Afternoon thunderstorm development also appears probable across western MN as the surface low interacts with the warm and moist airmass expected to be in place. Surface temperatures in the mid to upper 80s/low 90s amid upper 60s/low 70 dewpoints will support strong to very strong buoyancy, with MLCAPE over 3000 J/kg probable. Moderate vertical shear is anticipated across the region, but precipitation-laden updrafts are still expected to promote a predominantly outflow-dominant storm mode. Some outflow amalgamation is possible, with the resulting convective line then progressing southeastward into west-central WI. Primary severe threat is damaging gusts, but isolated large hail is possible with early cellular development. Outflow-dominant storm mode should keep the tornado threat low, but more southerly flow is possible near the surface low, with surface vorticity greater in this region as well. This could result in some low-probability tornado potential. ...Northeast MT into northern ND... Combination of low-level convergence along the lee trough and moderate low-level moisture (likely via post-frontal upslope flow) may result in convective initiation over northeast MT. Easterly low-level flow veering to westerly aloft will support strong vertical shear capable of maintaining a supercellular storm mode. Large hail and/or damaging gusts are the primary risks with these storms as the move eastward into northwest/northern ND. ...Western/Central SD and the NE Panhandle... Isolated thunderstorm development is possible Saturday afternoon amid the low-level convergence across western SD and the NE Panhandle. High cloud bases and moderate northwesterly flow aloft could support a few strong downbursts with any more robust convection. ...Lower MO Valley/Ozark Plateau into the Lower OH Valley... Thunderstorms may be ongoing over the Lower MO Valley/Ozark Plateau early Saturday morning, supported by warm-air advection associated with the low-level jet. These storms will likely be sub-severe, but an associated convectively induced vorticity maximum may drift eastward throughout the day, leading to additional storm development during the afternoon across the Lower OH Valley. Current expectation is that modest vertical shear should limit the severe potential within these storms. ..Mosier.. 07/12/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN PLAINS INTO THE UPPER MIDWEST... ...SUMMARY... Multiple clusters of strong to severe thunderstorms are possible across portions of the Northern Plains into the Upper Mississippi Valley on Saturday. ...Synopsis... Upper ridging is forecast to be centered over the Four Corners early Saturday morning, remaining largely in place for the remainder of the period. An upper trough is expected to progress through north-central Canada, contributing to moderate westerly mid-level flow between this trough and the Four Corners ridging. A shortwave trough will likely move through this westerly flow, progressing across the northern Plains/southern Canadian Prairie Provinces into the Upper Midwest. Primary surface low associated with this wave will likely move just ahead of it from central Manitoba into far northwestern Ontario. A secondary surface low may develop at the triple point, with this low likely moving from central ND eastward across northern MN. Farther east, a shortwave trough is forecast to progress eastward from southern Quebec/western NY across the Northeast while subtropical ridging persists over the Southeast. ...Eastern Dakotas into the Upper Midwest... A very moist airmass will likely be in place from the eastern Dakotas into the Upper Midwest on Saturday morning, preceding the shortwave trough and associated surface features mentioned in the synopsis. Some isolated thunderstorms may be ongoing across MN early Saturday morning, supported by warm-air advection throughout the warm sector. Evolution of this early morning convection is uncertain, but it will likely shift gradually southeastward throughout the morning, potentially persisting long enough to become surface-based in the northeast IA/southern WI/northern IL vicinity. If this scenario is realized, the primary severe threat would be damaging gusts. Afternoon thunderstorm development also appears probable across western MN as the surface low interacts with the warm and moist airmass expected to be in place. Surface temperatures in the mid to upper 80s/low 90s amid upper 60s/low 70 dewpoints will support strong to very strong buoyancy, with MLCAPE over 3000 J/kg probable. Moderate vertical shear is anticipated across the region, but precipitation-laden updrafts are still expected to promote a predominantly outflow-dominant storm mode. Some outflow amalgamation is possible, with the resulting convective line then progressing southeastward into west-central WI. Primary severe threat is damaging gusts, but isolated large hail is possible with early cellular development. Outflow-dominant storm mode should keep the tornado threat low, but more southerly flow is possible near the surface low, with surface vorticity greater in this region as well. This could result in some low-probability tornado potential. ...Northeast MT into northern ND... Combination of low-level convergence along the lee trough and moderate low-level moisture (likely via post-frontal upslope flow) may result in convective initiation over northeast MT. Easterly low-level flow veering to westerly aloft will support strong vertical shear capable of maintaining a supercellular storm mode. Large hail and/or damaging gusts are the primary risks with these storms as the move eastward into northwest/northern ND. ...Western/Central SD and the NE Panhandle... Isolated thunderstorm development is possible Saturday afternoon amid the low-level convergence across western SD and the NE Panhandle. High cloud bases and moderate northwesterly flow aloft could support a few strong downbursts with any more robust convection. ...Lower MO Valley/Ozark Plateau into the Lower OH Valley... Thunderstorms may be ongoing over the Lower MO Valley/Ozark Plateau early Saturday morning, supported by warm-air advection associated with the low-level jet. These storms will likely be sub-severe, but an associated convectively induced vorticity maximum may drift eastward throughout the day, leading to additional storm development during the afternoon across the Lower OH Valley. Current expectation is that modest vertical shear should limit the severe potential within these storms. ..Mosier.. 07/12/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN PLAINS INTO THE UPPER MIDWEST... ...SUMMARY... Multiple clusters of strong to severe thunderstorms are possible across portions of the Northern Plains into the Upper Mississippi Valley on Saturday. ...Synopsis... Upper ridging is forecast to be centered over the Four Corners early Saturday morning, remaining largely in place for the remainder of the period. An upper trough is expected to progress through north-central Canada, contributing to moderate westerly mid-level flow between this trough and the Four Corners ridging. A shortwave trough will likely move through this westerly flow, progressing across the northern Plains/southern Canadian Prairie Provinces into the Upper Midwest. Primary surface low associated with this wave will likely move just ahead of it from central Manitoba into far northwestern Ontario. A secondary surface low may develop at the triple point, with this low likely moving from central ND eastward across northern MN. Farther east, a shortwave trough is forecast to progress eastward from southern Quebec/western NY across the Northeast while subtropical ridging persists over the Southeast. ...Eastern Dakotas into the Upper Midwest... A very moist airmass will likely be in place from the eastern Dakotas into the Upper Midwest on Saturday morning, preceding the shortwave trough and associated surface features mentioned in the synopsis. Some isolated thunderstorms may be ongoing across MN early Saturday morning, supported by warm-air advection throughout the warm sector. Evolution of this early morning convection is uncertain, but it will likely shift gradually southeastward throughout the morning, potentially persisting long enough to become surface-based in the northeast IA/southern WI/northern IL vicinity. If this scenario is realized, the primary severe threat would be damaging gusts. Afternoon thunderstorm development also appears probable across western MN as the surface low interacts with the warm and moist airmass expected to be in place. Surface temperatures in the mid to upper 80s/low 90s amid upper 60s/low 70 dewpoints will support strong to very strong buoyancy, with MLCAPE over 3000 J/kg probable. Moderate vertical shear is anticipated across the region, but precipitation-laden updrafts are still expected to promote a predominantly outflow-dominant storm mode. Some outflow amalgamation is possible, with the resulting convective line then progressing southeastward into west-central WI. Primary severe threat is damaging gusts, but isolated large hail is possible with early cellular development. Outflow-dominant storm mode should keep the tornado threat low, but more southerly flow is possible near the surface low, with surface vorticity greater in this region as well. This could result in some low-probability tornado potential. ...Northeast MT into northern ND... Combination of low-level convergence along the lee trough and moderate low-level moisture (likely via post-frontal upslope flow) may result in convective initiation over northeast MT. Easterly low-level flow veering to westerly aloft will support strong vertical shear capable of maintaining a supercellular storm mode. Large hail and/or damaging gusts are the primary risks with these storms as the move eastward into northwest/northern ND. ...Western/Central SD and the NE Panhandle... Isolated thunderstorm development is possible Saturday afternoon amid the low-level convergence across western SD and the NE Panhandle. High cloud bases and moderate northwesterly flow aloft could support a few strong downbursts with any more robust convection. ...Lower MO Valley/Ozark Plateau into the Lower OH Valley... Thunderstorms may be ongoing over the Lower MO Valley/Ozark Plateau early Saturday morning, supported by warm-air advection associated with the low-level jet. These storms will likely be sub-severe, but an associated convectively induced vorticity maximum may drift eastward throughout the day, leading to additional storm development during the afternoon across the Lower OH Valley. Current expectation is that modest vertical shear should limit the severe potential within these storms. ..Mosier.. 07/12/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN PLAINS INTO THE UPPER MIDWEST... ...SUMMARY... Multiple clusters of strong to severe thunderstorms are possible across portions of the Northern Plains into the Upper Mississippi Valley on Saturday. ...Synopsis... Upper ridging is forecast to be centered over the Four Corners early Saturday morning, remaining largely in place for the remainder of the period. An upper trough is expected to progress through north-central Canada, contributing to moderate westerly mid-level flow between this trough and the Four Corners ridging. A shortwave trough will likely move through this westerly flow, progressing across the northern Plains/southern Canadian Prairie Provinces into the Upper Midwest. Primary surface low associated with this wave will likely move just ahead of it from central Manitoba into far northwestern Ontario. A secondary surface low may develop at the triple point, with this low likely moving from central ND eastward across northern MN. Farther east, a shortwave trough is forecast to progress eastward from southern Quebec/western NY across the Northeast while subtropical ridging persists over the Southeast. ...Eastern Dakotas into the Upper Midwest... A very moist airmass will likely be in place from the eastern Dakotas into the Upper Midwest on Saturday morning, preceding the shortwave trough and associated surface features mentioned in the synopsis. Some isolated thunderstorms may be ongoing across MN early Saturday morning, supported by warm-air advection throughout the warm sector. Evolution of this early morning convection is uncertain, but it will likely shift gradually southeastward throughout the morning, potentially persisting long enough to become surface-based in the northeast IA/southern WI/northern IL vicinity. If this scenario is realized, the primary severe threat would be damaging gusts. Afternoon thunderstorm development also appears probable across western MN as the surface low interacts with the warm and moist airmass expected to be in place. Surface temperatures in the mid to upper 80s/low 90s amid upper 60s/low 70 dewpoints will support strong to very strong buoyancy, with MLCAPE over 3000 J/kg probable. Moderate vertical shear is anticipated across the region, but precipitation-laden updrafts are still expected to promote a predominantly outflow-dominant storm mode. Some outflow amalgamation is possible, with the resulting convective line then progressing southeastward into west-central WI. Primary severe threat is damaging gusts, but isolated large hail is possible with early cellular development. Outflow-dominant storm mode should keep the tornado threat low, but more southerly flow is possible near the surface low, with surface vorticity greater in this region as well. This could result in some low-probability tornado potential. ...Northeast MT into northern ND... Combination of low-level convergence along the lee trough and moderate low-level moisture (likely via post-frontal upslope flow) may result in convective initiation over northeast MT. Easterly low-level flow veering to westerly aloft will support strong vertical shear capable of maintaining a supercellular storm mode. Large hail and/or damaging gusts are the primary risks with these storms as the move eastward into northwest/northern ND. ...Western/Central SD and the NE Panhandle... Isolated thunderstorm development is possible Saturday afternoon amid the low-level convergence across western SD and the NE Panhandle. High cloud bases and moderate northwesterly flow aloft could support a few strong downbursts with any more robust convection. ...Lower MO Valley/Ozark Plateau into the Lower OH Valley... Thunderstorms may be ongoing over the Lower MO Valley/Ozark Plateau early Saturday morning, supported by warm-air advection associated with the low-level jet. These storms will likely be sub-severe, but an associated convectively induced vorticity maximum may drift eastward throughout the day, leading to additional storm development during the afternoon across the Lower OH Valley. Current expectation is that modest vertical shear should limit the severe potential within these storms. ..Mosier.. 07/12/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1243 AM CDT Fri Jul 12 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN AND CENTRAL GREAT PLAINS... ...SUMMARY... Isolated severe wind and hail will be possible over the northern and central Great Plains from late afternoon into tonight. ...Northern/central Great Plains... Hot temperatures from the upper 90s to 105 will be prevalent near a surface trough extending from the MT/ND border area to eastern CO. Rich boundary-layer moisture will be displaced farther east across the central to eastern Dakotas to the Lower MO Valley, beneath an elevated mixed layer and modest capping. Scattered high-based thunderstorms will most likely develop during the late afternoon to early evening, within the uncapped and deeply mixed environment along the surface trough. In the mid-levels, the region will lie within a modest northwesterly flow regime between a stout anticyclone over the southern Great Basin and a low-amplitude shortwave trough in the eastern Great Lakes. This flow orientation should result in outflow-dominated cells/clusters impinging on greater buoyancy downstream. This may sustain a severe wind threat past sunset into the lower plains. In addition, a modest low-level warm advection regime tonight within a conditionally favorable supercell environment could support a threat for large hail, similar to what occurred on Thursday evening in the Kansas City Metro vicinity. Spatial confidence is low given the expected weak large-scale forcing for ascent. Still, have broadened the level 1-MRGL risk eastward to account for both possibilities. ..Grams/Moore.. 07/12/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1243 AM CDT Fri Jul 12 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN AND CENTRAL GREAT PLAINS... ...SUMMARY... Isolated severe wind and hail will be possible over the northern and central Great Plains from late afternoon into tonight. ...Northern/central Great Plains... Hot temperatures from the upper 90s to 105 will be prevalent near a surface trough extending from the MT/ND border area to eastern CO. Rich boundary-layer moisture will be displaced farther east across the central to eastern Dakotas to the Lower MO Valley, beneath an elevated mixed layer and modest capping. Scattered high-based thunderstorms will most likely develop during the late afternoon to early evening, within the uncapped and deeply mixed environment along the surface trough. In the mid-levels, the region will lie within a modest northwesterly flow regime between a stout anticyclone over the southern Great Basin and a low-amplitude shortwave trough in the eastern Great Lakes. This flow orientation should result in outflow-dominated cells/clusters impinging on greater buoyancy downstream. This may sustain a severe wind threat past sunset into the lower plains. In addition, a modest low-level warm advection regime tonight within a conditionally favorable supercell environment could support a threat for large hail, similar to what occurred on Thursday evening in the Kansas City Metro vicinity. Spatial confidence is low given the expected weak large-scale forcing for ascent. Still, have broadened the level 1-MRGL risk eastward to account for both possibilities. ..Grams/Moore.. 07/12/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1243 AM CDT Fri Jul 12 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN AND CENTRAL GREAT PLAINS... ...SUMMARY... Isolated severe wind and hail will be possible over the northern and central Great Plains from late afternoon into tonight. ...Northern/central Great Plains... Hot temperatures from the upper 90s to 105 will be prevalent near a surface trough extending from the MT/ND border area to eastern CO. Rich boundary-layer moisture will be displaced farther east across the central to eastern Dakotas to the Lower MO Valley, beneath an elevated mixed layer and modest capping. Scattered high-based thunderstorms will most likely develop during the late afternoon to early evening, within the uncapped and deeply mixed environment along the surface trough. In the mid-levels, the region will lie within a modest northwesterly flow regime between a stout anticyclone over the southern Great Basin and a low-amplitude shortwave trough in the eastern Great Lakes. This flow orientation should result in outflow-dominated cells/clusters impinging on greater buoyancy downstream. This may sustain a severe wind threat past sunset into the lower plains. In addition, a modest low-level warm advection regime tonight within a conditionally favorable supercell environment could support a threat for large hail, similar to what occurred on Thursday evening in the Kansas City Metro vicinity. Spatial confidence is low given the expected weak large-scale forcing for ascent. Still, have broadened the level 1-MRGL risk eastward to account for both possibilities. ..Grams/Moore.. 07/12/2024 Read more