Severe Storms

No watches are valid as of Wed Aug 21 19:57:02 UTC 2024.

MD 1967 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR EASTERN WY INTO WESTERN SD/NE
Mesoscale Discussion 1967 NWS Storm Prediction Center Norman OK 0255 PM CDT Wed Aug 21 2024 Areas affected...eastern WY into western SD/NE Concerning...Severe potential...Watch possible Valid 211955Z - 212100Z Probability of Watch Issuance...40 percent SUMMARY...Isolated strong to severe thunderstorms may produce gusts of 55-70 mph and hail to 1.5 inches into this evening. Portions of the area may need a severe thunderstorm watch, but timing is uncertain. DISCUSSION...Convection is increasing across WY and western SD/NE this afternoon where strong heating into the 90s F has occurred. Boundary-layer moisture remains modest across much of the area, though 60s F dewpoints are noted into parts of SD. Cool temperatures aloft, aiding in steep midlevel lapse rates, are supporting weak to moderate instability across the region. High-based storms initially developing near higher terrain may pose a risk for strong outflow winds. Clustering may occur with eastward extent toward late afternoon/early evening as storms move into a more moist and unstable environment. Damaging gusts will be possible with this activity. Additionally, modest vertical shear amid a steep lapse rates environment could support a few instance of large hail in the 1-1.5 inch range with any stronger/longer-lived thunderstorm cores. The MCD area is being monitored for possible watch issuance this afternoon. ..Leitman/Hart.. 08/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ABR...LBF...UNR...CYS... LAT...LON 41060348 41020469 41070553 41350576 41830586 43370504 44390444 45020396 45150363 45170238 45000169 44230117 43100105 41550215 41040322 41060348 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Wed Aug 21 2024 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEVADA... ...20z Updated... The previous outlook remains valid with only minor changes for the latest guidance. Sporadic thunderstorms are possible over parts of north-central OR late D2/Thursday into early D3/Friday. While a few of these storms may be on the drier side, confidence in the coverage of storms and lightning over dry fuels remains too low for dry thunder probabilities. See the prior discussion. ..Lyons.. 08/21/2024 .PREV DISCUSSION... /ISSUED 0145 AM CDT Wed Aug 21 2024/ ...Synopsis... A southward-moving shortwave trough is forecast to approach the Oregon/Washington coasts on Thursday, before moving east on Friday. This will result in an intensified height gradient across the Great Basin and a deepening surface low over Oregon that will bring widespread dry/windy conditions to portions of Oregon, Nevada, and Idaho. ...Dry/Windy... Critical fire-weather conditions are forecast across southwestern and central Nevada, where single-digit relative humidity values and winds of 25-30 MPH will overlap with ERC values exceeding the 80th-98th annual percentiles. Uncertainty exists in the eastward extent of the Critical area due to recent wetting rainfall and a tight gradient in fuel receptiveness to wildfire spread, and some areal expansion may be needed in future updates. Elevated fire-weather conditions are expected on the periphery of the Critical highlight area, as well as portions of northwestern Nevada into southeastern Oregon. Southeastern Oregon and northwestern Nevada will have slightly higher boundary-layer relative humidity values of 10-15%, and slightly slower wind speeds of 20-25 MPH. However, fuels in the region are widely receptive to wildfire spread, and if surface winds trend higher, a subsequent upgrade to Critical may be needed in this area. ...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 Wed Aug 21 2024 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEVADA... ...20z Updated... The previous outlook remains valid with only minor changes for the latest guidance. Sporadic thunderstorms are possible over parts of north-central OR late D2/Thursday into early D3/Friday. While a few of these storms may be on the drier side, confidence in the coverage of storms and lightning over dry fuels remains too low for dry thunder probabilities. See the prior discussion. ..Lyons.. 08/21/2024 .PREV DISCUSSION... /ISSUED 0145 AM CDT Wed Aug 21 2024/ ...Synopsis... A southward-moving shortwave trough is forecast to approach the Oregon/Washington coasts on Thursday, before moving east on Friday. This will result in an intensified height gradient across the Great Basin and a deepening surface low over Oregon that will bring widespread dry/windy conditions to portions of Oregon, Nevada, and Idaho. ...Dry/Windy... Critical fire-weather conditions are forecast across southwestern and central Nevada, where single-digit relative humidity values and winds of 25-30 MPH will overlap with ERC values exceeding the 80th-98th annual percentiles. Uncertainty exists in the eastward extent of the Critical area due to recent wetting rainfall and a tight gradient in fuel receptiveness to wildfire spread, and some areal expansion may be needed in future updates. Elevated fire-weather conditions are expected on the periphery of the Critical highlight area, as well as portions of northwestern Nevada into southeastern Oregon. Southeastern Oregon and northwestern Nevada will have slightly higher boundary-layer relative humidity values of 10-15%, and slightly slower wind speeds of 20-25 MPH. However, fuels in the region are widely receptive to wildfire spread, and if surface winds trend higher, a subsequent upgrade to Critical may be needed in this area. ...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 Wed Aug 21 2024 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEVADA... ...20z Updated... The previous outlook remains valid with only minor changes for the latest guidance. Sporadic thunderstorms are possible over parts of north-central OR late D2/Thursday into early D3/Friday. While a few of these storms may be on the drier side, confidence in the coverage of storms and lightning over dry fuels remains too low for dry thunder probabilities. See the prior discussion. ..Lyons.. 08/21/2024 .PREV DISCUSSION... /ISSUED 0145 AM CDT Wed Aug 21 2024/ ...Synopsis... A southward-moving shortwave trough is forecast to approach the Oregon/Washington coasts on Thursday, before moving east on Friday. This will result in an intensified height gradient across the Great Basin and a deepening surface low over Oregon that will bring widespread dry/windy conditions to portions of Oregon, Nevada, and Idaho. ...Dry/Windy... Critical fire-weather conditions are forecast across southwestern and central Nevada, where single-digit relative humidity values and winds of 25-30 MPH will overlap with ERC values exceeding the 80th-98th annual percentiles. Uncertainty exists in the eastward extent of the Critical area due to recent wetting rainfall and a tight gradient in fuel receptiveness to wildfire spread, and some areal expansion may be needed in future updates. Elevated fire-weather conditions are expected on the periphery of the Critical highlight area, as well as portions of northwestern Nevada into southeastern Oregon. Southeastern Oregon and northwestern Nevada will have slightly higher boundary-layer relative humidity values of 10-15%, and slightly slower wind speeds of 20-25 MPH. However, fuels in the region are widely receptive to wildfire spread, and if surface winds trend higher, a subsequent upgrade to Critical may be needed in this area. ...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 Wed Aug 21 2024 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEVADA... ...20z Updated... The previous outlook remains valid with only minor changes for the latest guidance. Sporadic thunderstorms are possible over parts of north-central OR late D2/Thursday into early D3/Friday. While a few of these storms may be on the drier side, confidence in the coverage of storms and lightning over dry fuels remains too low for dry thunder probabilities. See the prior discussion. ..Lyons.. 08/21/2024 .PREV DISCUSSION... /ISSUED 0145 AM CDT Wed Aug 21 2024/ ...Synopsis... A southward-moving shortwave trough is forecast to approach the Oregon/Washington coasts on Thursday, before moving east on Friday. This will result in an intensified height gradient across the Great Basin and a deepening surface low over Oregon that will bring widespread dry/windy conditions to portions of Oregon, Nevada, and Idaho. ...Dry/Windy... Critical fire-weather conditions are forecast across southwestern and central Nevada, where single-digit relative humidity values and winds of 25-30 MPH will overlap with ERC values exceeding the 80th-98th annual percentiles. Uncertainty exists in the eastward extent of the Critical area due to recent wetting rainfall and a tight gradient in fuel receptiveness to wildfire spread, and some areal expansion may be needed in future updates. Elevated fire-weather conditions are expected on the periphery of the Critical highlight area, as well as portions of northwestern Nevada into southeastern Oregon. Southeastern Oregon and northwestern Nevada will have slightly higher boundary-layer relative humidity values of 10-15%, and slightly slower wind speeds of 20-25 MPH. However, fuels in the region are widely receptive to wildfire spread, and if surface winds trend higher, a subsequent upgrade to Critical may be needed in this area. ...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 Wed Aug 21 2024 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEVADA... ...20z Updated... The previous outlook remains valid with only minor changes for the latest guidance. Sporadic thunderstorms are possible over parts of north-central OR late D2/Thursday into early D3/Friday. While a few of these storms may be on the drier side, confidence in the coverage of storms and lightning over dry fuels remains too low for dry thunder probabilities. See the prior discussion. ..Lyons.. 08/21/2024 .PREV DISCUSSION... /ISSUED 0145 AM CDT Wed Aug 21 2024/ ...Synopsis... A southward-moving shortwave trough is forecast to approach the Oregon/Washington coasts on Thursday, before moving east on Friday. This will result in an intensified height gradient across the Great Basin and a deepening surface low over Oregon that will bring widespread dry/windy conditions to portions of Oregon, Nevada, and Idaho. ...Dry/Windy... Critical fire-weather conditions are forecast across southwestern and central Nevada, where single-digit relative humidity values and winds of 25-30 MPH will overlap with ERC values exceeding the 80th-98th annual percentiles. Uncertainty exists in the eastward extent of the Critical area due to recent wetting rainfall and a tight gradient in fuel receptiveness to wildfire spread, and some areal expansion may be needed in future updates. Elevated fire-weather conditions are expected on the periphery of the Critical highlight area, as well as portions of northwestern Nevada into southeastern Oregon. Southeastern Oregon and northwestern Nevada will have slightly higher boundary-layer relative humidity values of 10-15%, and slightly slower wind speeds of 20-25 MPH. However, fuels in the region are widely receptive to wildfire spread, and if surface winds trend higher, a subsequent upgrade to Critical may be needed in this area. ...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 Wed Aug 21 2024 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEVADA... ...20z Updated... The previous outlook remains valid with only minor changes for the latest guidance. Sporadic thunderstorms are possible over parts of north-central OR late D2/Thursday into early D3/Friday. While a few of these storms may be on the drier side, confidence in the coverage of storms and lightning over dry fuels remains too low for dry thunder probabilities. See the prior discussion. ..Lyons.. 08/21/2024 .PREV DISCUSSION... /ISSUED 0145 AM CDT Wed Aug 21 2024/ ...Synopsis... A southward-moving shortwave trough is forecast to approach the Oregon/Washington coasts on Thursday, before moving east on Friday. This will result in an intensified height gradient across the Great Basin and a deepening surface low over Oregon that will bring widespread dry/windy conditions to portions of Oregon, Nevada, and Idaho. ...Dry/Windy... Critical fire-weather conditions are forecast across southwestern and central Nevada, where single-digit relative humidity values and winds of 25-30 MPH will overlap with ERC values exceeding the 80th-98th annual percentiles. Uncertainty exists in the eastward extent of the Critical area due to recent wetting rainfall and a tight gradient in fuel receptiveness to wildfire spread, and some areal expansion may be needed in future updates. Elevated fire-weather conditions are expected on the periphery of the Critical highlight area, as well as portions of northwestern Nevada into southeastern Oregon. Southeastern Oregon and northwestern Nevada will have slightly higher boundary-layer relative humidity values of 10-15%, and slightly slower wind speeds of 20-25 MPH. However, fuels in the region are widely receptive to wildfire spread, and if surface winds trend higher, a subsequent upgrade to Critical may be needed in this area. ...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 Wed Aug 21 2024 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEVADA... ...20z Updated... The previous outlook remains valid with only minor changes for the latest guidance. Sporadic thunderstorms are possible over parts of north-central OR late D2/Thursday into early D3/Friday. While a few of these storms may be on the drier side, confidence in the coverage of storms and lightning over dry fuels remains too low for dry thunder probabilities. See the prior discussion. ..Lyons.. 08/21/2024 .PREV DISCUSSION... /ISSUED 0145 AM CDT Wed Aug 21 2024/ ...Synopsis... A southward-moving shortwave trough is forecast to approach the Oregon/Washington coasts on Thursday, before moving east on Friday. This will result in an intensified height gradient across the Great Basin and a deepening surface low over Oregon that will bring widespread dry/windy conditions to portions of Oregon, Nevada, and Idaho. ...Dry/Windy... Critical fire-weather conditions are forecast across southwestern and central Nevada, where single-digit relative humidity values and winds of 25-30 MPH will overlap with ERC values exceeding the 80th-98th annual percentiles. Uncertainty exists in the eastward extent of the Critical area due to recent wetting rainfall and a tight gradient in fuel receptiveness to wildfire spread, and some areal expansion may be needed in future updates. Elevated fire-weather conditions are expected on the periphery of the Critical highlight area, as well as portions of northwestern Nevada into southeastern Oregon. Southeastern Oregon and northwestern Nevada will have slightly higher boundary-layer relative humidity values of 10-15%, and slightly slower wind speeds of 20-25 MPH. However, fuels in the region are widely receptive to wildfire spread, and if surface winds trend higher, a subsequent upgrade to Critical may be needed in this area. ...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 Wed Aug 21 2024 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEVADA... ...20z Updated... The previous outlook remains valid with only minor changes for the latest guidance. Sporadic thunderstorms are possible over parts of north-central OR late D2/Thursday into early D3/Friday. While a few of these storms may be on the drier side, confidence in the coverage of storms and lightning over dry fuels remains too low for dry thunder probabilities. See the prior discussion. ..Lyons.. 08/21/2024 .PREV DISCUSSION... /ISSUED 0145 AM CDT Wed Aug 21 2024/ ...Synopsis... A southward-moving shortwave trough is forecast to approach the Oregon/Washington coasts on Thursday, before moving east on Friday. This will result in an intensified height gradient across the Great Basin and a deepening surface low over Oregon that will bring widespread dry/windy conditions to portions of Oregon, Nevada, and Idaho. ...Dry/Windy... Critical fire-weather conditions are forecast across southwestern and central Nevada, where single-digit relative humidity values and winds of 25-30 MPH will overlap with ERC values exceeding the 80th-98th annual percentiles. Uncertainty exists in the eastward extent of the Critical area due to recent wetting rainfall and a tight gradient in fuel receptiveness to wildfire spread, and some areal expansion may be needed in future updates. Elevated fire-weather conditions are expected on the periphery of the Critical highlight area, as well as portions of northwestern Nevada into southeastern Oregon. Southeastern Oregon and northwestern Nevada will have slightly higher boundary-layer relative humidity values of 10-15%, and slightly slower wind speeds of 20-25 MPH. However, fuels in the region are widely receptive to wildfire spread, and if surface winds trend higher, a subsequent upgrade to Critical may be needed in this area. ...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 Wed Aug 21 2024 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEVADA... ...20z Updated... The previous outlook remains valid with only minor changes for the latest guidance. Sporadic thunderstorms are possible over parts of north-central OR late D2/Thursday into early D3/Friday. While a few of these storms may be on the drier side, confidence in the coverage of storms and lightning over dry fuels remains too low for dry thunder probabilities. See the prior discussion. ..Lyons.. 08/21/2024 .PREV DISCUSSION... /ISSUED 0145 AM CDT Wed Aug 21 2024/ ...Synopsis... A southward-moving shortwave trough is forecast to approach the Oregon/Washington coasts on Thursday, before moving east on Friday. This will result in an intensified height gradient across the Great Basin and a deepening surface low over Oregon that will bring widespread dry/windy conditions to portions of Oregon, Nevada, and Idaho. ...Dry/Windy... Critical fire-weather conditions are forecast across southwestern and central Nevada, where single-digit relative humidity values and winds of 25-30 MPH will overlap with ERC values exceeding the 80th-98th annual percentiles. Uncertainty exists in the eastward extent of the Critical area due to recent wetting rainfall and a tight gradient in fuel receptiveness to wildfire spread, and some areal expansion may be needed in future updates. Elevated fire-weather conditions are expected on the periphery of the Critical highlight area, as well as portions of northwestern Nevada into southeastern Oregon. Southeastern Oregon and northwestern Nevada will have slightly higher boundary-layer relative humidity values of 10-15%, and slightly slower wind speeds of 20-25 MPH. However, fuels in the region are widely receptive to wildfire spread, and if surface winds trend higher, a subsequent upgrade to Critical may be needed in this area. ...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 Wed Aug 21 2024 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEVADA... ...20z Updated... The previous outlook remains valid with only minor changes for the latest guidance. Sporadic thunderstorms are possible over parts of north-central OR late D2/Thursday into early D3/Friday. While a few of these storms may be on the drier side, confidence in the coverage of storms and lightning over dry fuels remains too low for dry thunder probabilities. See the prior discussion. ..Lyons.. 08/21/2024 .PREV DISCUSSION... /ISSUED 0145 AM CDT Wed Aug 21 2024/ ...Synopsis... A southward-moving shortwave trough is forecast to approach the Oregon/Washington coasts on Thursday, before moving east on Friday. This will result in an intensified height gradient across the Great Basin and a deepening surface low over Oregon that will bring widespread dry/windy conditions to portions of Oregon, Nevada, and Idaho. ...Dry/Windy... Critical fire-weather conditions are forecast across southwestern and central Nevada, where single-digit relative humidity values and winds of 25-30 MPH will overlap with ERC values exceeding the 80th-98th annual percentiles. Uncertainty exists in the eastward extent of the Critical area due to recent wetting rainfall and a tight gradient in fuel receptiveness to wildfire spread, and some areal expansion may be needed in future updates. Elevated fire-weather conditions are expected on the periphery of the Critical highlight area, as well as portions of northwestern Nevada into southeastern Oregon. Southeastern Oregon and northwestern Nevada will have slightly higher boundary-layer relative humidity values of 10-15%, and slightly slower wind speeds of 20-25 MPH. However, fuels in the region are widely receptive to wildfire spread, and if surface winds trend higher, a subsequent upgrade to Critical may be needed in this area. ...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 Wed Aug 21 2024 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEVADA... ...20z Updated... The previous outlook remains valid with only minor changes for the latest guidance. Sporadic thunderstorms are possible over parts of north-central OR late D2/Thursday into early D3/Friday. While a few of these storms may be on the drier side, confidence in the coverage of storms and lightning over dry fuels remains too low for dry thunder probabilities. See the prior discussion. ..Lyons.. 08/21/2024 .PREV DISCUSSION... /ISSUED 0145 AM CDT Wed Aug 21 2024/ ...Synopsis... A southward-moving shortwave trough is forecast to approach the Oregon/Washington coasts on Thursday, before moving east on Friday. This will result in an intensified height gradient across the Great Basin and a deepening surface low over Oregon that will bring widespread dry/windy conditions to portions of Oregon, Nevada, and Idaho. ...Dry/Windy... Critical fire-weather conditions are forecast across southwestern and central Nevada, where single-digit relative humidity values and winds of 25-30 MPH will overlap with ERC values exceeding the 80th-98th annual percentiles. Uncertainty exists in the eastward extent of the Critical area due to recent wetting rainfall and a tight gradient in fuel receptiveness to wildfire spread, and some areal expansion may be needed in future updates. Elevated fire-weather conditions are expected on the periphery of the Critical highlight area, as well as portions of northwestern Nevada into southeastern Oregon. Southeastern Oregon and northwestern Nevada will have slightly higher boundary-layer relative humidity values of 10-15%, and slightly slower wind speeds of 20-25 MPH. However, fuels in the region are widely receptive to wildfire spread, and if surface winds trend higher, a subsequent upgrade to Critical may be needed in this area. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Wed Aug 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN HIGH PLAINS... ...SUMMARY... Severe hail and thunderstorm gusts are most probable today over parts of eastern Montana and the western Dakotas. ...20Z Update... The previous forecast remains on track for the northern and central High Plains based on recent observed trends and latest forecast guidance. The Marginal risk area across south-central AZ has been modified to remove areas that have seen little diurnal destabilization owing to persistent stratiform rain and/or cirrus emanating from a broken line of weak convection. Additionally, wind risk probabilities have been expanded slightly east to account for recent thunderstorm development within a similarly buoyant and deeply-mixed environment as the remainder of the risk area. See the previous discussion for additional details. ..Moore.. 08/21/2024 .PREV DISCUSSION... /ISSUED 1120 AM CDT Wed Aug 21 2024/ ...Northern High Plains... Morning water vapor imagery shows a fast-moving shortwave trough over ID/NV tracking northeastward. Lift associated with this system will overspread parts of MT/WY/Dakotas later this afternoon and evening. This will help to initiate scattered thunderstorms over the higher terrain of southern MT and WY, building eastward into the Plains during the evening. Instability in the mountains is quite weak with dewpoints only in the 40s, but with steep low/mid level lapse rates and moderately strong westerly flow aloft posing a risk of gusty winds. Storms will eventually move/develop eastward into a more moist/unstable air mass across eastern MT and western SD/ND where more robust/severe storms are expected, capable of damaging winds and large hail. ...CO/NE/KS... Ample mid-level moisture will result in scattered afternoon thunderstorms over the mountains of central CO and southern WY. This area will be on the fringe of the stronger westerly flow aloft, and with pockets of strong daytime heating helping to steepen low-level lapse rates. This will promote a risk of gusty/damaging winds in the strongest cells. As the activity spreads eastward into the Plains, further intensification is possible with a few cells continuing a risk of gusty winds and hail during the evening. ...Southeast AZ... Afternoon thunderstorms have been occurring daily over southeast AZ, with isolated strong cells capable of gusty winds. Today will be similar as daytime heating dewpoints in the 60s promote storms over the higher terrain that track slowly northwestward during the late afternoon and early evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Wed Aug 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN HIGH PLAINS... ...SUMMARY... Severe hail and thunderstorm gusts are most probable today over parts of eastern Montana and the western Dakotas. ...20Z Update... The previous forecast remains on track for the northern and central High Plains based on recent observed trends and latest forecast guidance. The Marginal risk area across south-central AZ has been modified to remove areas that have seen little diurnal destabilization owing to persistent stratiform rain and/or cirrus emanating from a broken line of weak convection. Additionally, wind risk probabilities have been expanded slightly east to account for recent thunderstorm development within a similarly buoyant and deeply-mixed environment as the remainder of the risk area. See the previous discussion for additional details. ..Moore.. 08/21/2024 .PREV DISCUSSION... /ISSUED 1120 AM CDT Wed Aug 21 2024/ ...Northern High Plains... Morning water vapor imagery shows a fast-moving shortwave trough over ID/NV tracking northeastward. Lift associated with this system will overspread parts of MT/WY/Dakotas later this afternoon and evening. This will help to initiate scattered thunderstorms over the higher terrain of southern MT and WY, building eastward into the Plains during the evening. Instability in the mountains is quite weak with dewpoints only in the 40s, but with steep low/mid level lapse rates and moderately strong westerly flow aloft posing a risk of gusty winds. Storms will eventually move/develop eastward into a more moist/unstable air mass across eastern MT and western SD/ND where more robust/severe storms are expected, capable of damaging winds and large hail. ...CO/NE/KS... Ample mid-level moisture will result in scattered afternoon thunderstorms over the mountains of central CO and southern WY. This area will be on the fringe of the stronger westerly flow aloft, and with pockets of strong daytime heating helping to steepen low-level lapse rates. This will promote a risk of gusty/damaging winds in the strongest cells. As the activity spreads eastward into the Plains, further intensification is possible with a few cells continuing a risk of gusty winds and hail during the evening. ...Southeast AZ... Afternoon thunderstorms have been occurring daily over southeast AZ, with isolated strong cells capable of gusty winds. Today will be similar as daytime heating dewpoints in the 60s promote storms over the higher terrain that track slowly northwestward during the late afternoon and early evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Wed Aug 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN HIGH PLAINS... ...SUMMARY... Severe hail and thunderstorm gusts are most probable today over parts of eastern Montana and the western Dakotas. ...20Z Update... The previous forecast remains on track for the northern and central High Plains based on recent observed trends and latest forecast guidance. The Marginal risk area across south-central AZ has been modified to remove areas that have seen little diurnal destabilization owing to persistent stratiform rain and/or cirrus emanating from a broken line of weak convection. Additionally, wind risk probabilities have been expanded slightly east to account for recent thunderstorm development within a similarly buoyant and deeply-mixed environment as the remainder of the risk area. See the previous discussion for additional details. ..Moore.. 08/21/2024 .PREV DISCUSSION... /ISSUED 1120 AM CDT Wed Aug 21 2024/ ...Northern High Plains... Morning water vapor imagery shows a fast-moving shortwave trough over ID/NV tracking northeastward. Lift associated with this system will overspread parts of MT/WY/Dakotas later this afternoon and evening. This will help to initiate scattered thunderstorms over the higher terrain of southern MT and WY, building eastward into the Plains during the evening. Instability in the mountains is quite weak with dewpoints only in the 40s, but with steep low/mid level lapse rates and moderately strong westerly flow aloft posing a risk of gusty winds. Storms will eventually move/develop eastward into a more moist/unstable air mass across eastern MT and western SD/ND where more robust/severe storms are expected, capable of damaging winds and large hail. ...CO/NE/KS... Ample mid-level moisture will result in scattered afternoon thunderstorms over the mountains of central CO and southern WY. This area will be on the fringe of the stronger westerly flow aloft, and with pockets of strong daytime heating helping to steepen low-level lapse rates. This will promote a risk of gusty/damaging winds in the strongest cells. As the activity spreads eastward into the Plains, further intensification is possible with a few cells continuing a risk of gusty winds and hail during the evening. ...Southeast AZ... Afternoon thunderstorms have been occurring daily over southeast AZ, with isolated strong cells capable of gusty winds. Today will be similar as daytime heating dewpoints in the 60s promote storms over the higher terrain that track slowly northwestward during the late afternoon and early evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Wed Aug 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN HIGH PLAINS... ...SUMMARY... Severe hail and thunderstorm gusts are most probable today over parts of eastern Montana and the western Dakotas. ...20Z Update... The previous forecast remains on track for the northern and central High Plains based on recent observed trends and latest forecast guidance. The Marginal risk area across south-central AZ has been modified to remove areas that have seen little diurnal destabilization owing to persistent stratiform rain and/or cirrus emanating from a broken line of weak convection. Additionally, wind risk probabilities have been expanded slightly east to account for recent thunderstorm development within a similarly buoyant and deeply-mixed environment as the remainder of the risk area. See the previous discussion for additional details. ..Moore.. 08/21/2024 .PREV DISCUSSION... /ISSUED 1120 AM CDT Wed Aug 21 2024/ ...Northern High Plains... Morning water vapor imagery shows a fast-moving shortwave trough over ID/NV tracking northeastward. Lift associated with this system will overspread parts of MT/WY/Dakotas later this afternoon and evening. This will help to initiate scattered thunderstorms over the higher terrain of southern MT and WY, building eastward into the Plains during the evening. Instability in the mountains is quite weak with dewpoints only in the 40s, but with steep low/mid level lapse rates and moderately strong westerly flow aloft posing a risk of gusty winds. Storms will eventually move/develop eastward into a more moist/unstable air mass across eastern MT and western SD/ND where more robust/severe storms are expected, capable of damaging winds and large hail. ...CO/NE/KS... Ample mid-level moisture will result in scattered afternoon thunderstorms over the mountains of central CO and southern WY. This area will be on the fringe of the stronger westerly flow aloft, and with pockets of strong daytime heating helping to steepen low-level lapse rates. This will promote a risk of gusty/damaging winds in the strongest cells. As the activity spreads eastward into the Plains, further intensification is possible with a few cells continuing a risk of gusty winds and hail during the evening. ...Southeast AZ... Afternoon thunderstorms have been occurring daily over southeast AZ, with isolated strong cells capable of gusty winds. Today will be similar as daytime heating dewpoints in the 60s promote storms over the higher terrain that track slowly northwestward during the late afternoon and early evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Wed Aug 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN HIGH PLAINS... ...SUMMARY... Severe hail and thunderstorm gusts are most probable today over parts of eastern Montana and the western Dakotas. ...20Z Update... The previous forecast remains on track for the northern and central High Plains based on recent observed trends and latest forecast guidance. The Marginal risk area across south-central AZ has been modified to remove areas that have seen little diurnal destabilization owing to persistent stratiform rain and/or cirrus emanating from a broken line of weak convection. Additionally, wind risk probabilities have been expanded slightly east to account for recent thunderstorm development within a similarly buoyant and deeply-mixed environment as the remainder of the risk area. See the previous discussion for additional details. ..Moore.. 08/21/2024 .PREV DISCUSSION... /ISSUED 1120 AM CDT Wed Aug 21 2024/ ...Northern High Plains... Morning water vapor imagery shows a fast-moving shortwave trough over ID/NV tracking northeastward. Lift associated with this system will overspread parts of MT/WY/Dakotas later this afternoon and evening. This will help to initiate scattered thunderstorms over the higher terrain of southern MT and WY, building eastward into the Plains during the evening. Instability in the mountains is quite weak with dewpoints only in the 40s, but with steep low/mid level lapse rates and moderately strong westerly flow aloft posing a risk of gusty winds. Storms will eventually move/develop eastward into a more moist/unstable air mass across eastern MT and western SD/ND where more robust/severe storms are expected, capable of damaging winds and large hail. ...CO/NE/KS... Ample mid-level moisture will result in scattered afternoon thunderstorms over the mountains of central CO and southern WY. This area will be on the fringe of the stronger westerly flow aloft, and with pockets of strong daytime heating helping to steepen low-level lapse rates. This will promote a risk of gusty/damaging winds in the strongest cells. As the activity spreads eastward into the Plains, further intensification is possible with a few cells continuing a risk of gusty winds and hail during the evening. ...Southeast AZ... Afternoon thunderstorms have been occurring daily over southeast AZ, with isolated strong cells capable of gusty winds. Today will be similar as daytime heating dewpoints in the 60s promote storms over the higher terrain that track slowly northwestward during the late afternoon and early evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Wed Aug 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN HIGH PLAINS... ...SUMMARY... Severe hail and thunderstorm gusts are most probable today over parts of eastern Montana and the western Dakotas. ...20Z Update... The previous forecast remains on track for the northern and central High Plains based on recent observed trends and latest forecast guidance. The Marginal risk area across south-central AZ has been modified to remove areas that have seen little diurnal destabilization owing to persistent stratiform rain and/or cirrus emanating from a broken line of weak convection. Additionally, wind risk probabilities have been expanded slightly east to account for recent thunderstorm development within a similarly buoyant and deeply-mixed environment as the remainder of the risk area. See the previous discussion for additional details. ..Moore.. 08/21/2024 .PREV DISCUSSION... /ISSUED 1120 AM CDT Wed Aug 21 2024/ ...Northern High Plains... Morning water vapor imagery shows a fast-moving shortwave trough over ID/NV tracking northeastward. Lift associated with this system will overspread parts of MT/WY/Dakotas later this afternoon and evening. This will help to initiate scattered thunderstorms over the higher terrain of southern MT and WY, building eastward into the Plains during the evening. Instability in the mountains is quite weak with dewpoints only in the 40s, but with steep low/mid level lapse rates and moderately strong westerly flow aloft posing a risk of gusty winds. Storms will eventually move/develop eastward into a more moist/unstable air mass across eastern MT and western SD/ND where more robust/severe storms are expected, capable of damaging winds and large hail. ...CO/NE/KS... Ample mid-level moisture will result in scattered afternoon thunderstorms over the mountains of central CO and southern WY. This area will be on the fringe of the stronger westerly flow aloft, and with pockets of strong daytime heating helping to steepen low-level lapse rates. This will promote a risk of gusty/damaging winds in the strongest cells. As the activity spreads eastward into the Plains, further intensification is possible with a few cells continuing a risk of gusty winds and hail during the evening. ...Southeast AZ... Afternoon thunderstorms have been occurring daily over southeast AZ, with isolated strong cells capable of gusty winds. Today will be similar as daytime heating dewpoints in the 60s promote storms over the higher terrain that track slowly northwestward during the late afternoon and early evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Wed Aug 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN HIGH PLAINS... ...SUMMARY... Severe hail and thunderstorm gusts are most probable today over parts of eastern Montana and the western Dakotas. ...20Z Update... The previous forecast remains on track for the northern and central High Plains based on recent observed trends and latest forecast guidance. The Marginal risk area across south-central AZ has been modified to remove areas that have seen little diurnal destabilization owing to persistent stratiform rain and/or cirrus emanating from a broken line of weak convection. Additionally, wind risk probabilities have been expanded slightly east to account for recent thunderstorm development within a similarly buoyant and deeply-mixed environment as the remainder of the risk area. See the previous discussion for additional details. ..Moore.. 08/21/2024 .PREV DISCUSSION... /ISSUED 1120 AM CDT Wed Aug 21 2024/ ...Northern High Plains... Morning water vapor imagery shows a fast-moving shortwave trough over ID/NV tracking northeastward. Lift associated with this system will overspread parts of MT/WY/Dakotas later this afternoon and evening. This will help to initiate scattered thunderstorms over the higher terrain of southern MT and WY, building eastward into the Plains during the evening. Instability in the mountains is quite weak with dewpoints only in the 40s, but with steep low/mid level lapse rates and moderately strong westerly flow aloft posing a risk of gusty winds. Storms will eventually move/develop eastward into a more moist/unstable air mass across eastern MT and western SD/ND where more robust/severe storms are expected, capable of damaging winds and large hail. ...CO/NE/KS... Ample mid-level moisture will result in scattered afternoon thunderstorms over the mountains of central CO and southern WY. This area will be on the fringe of the stronger westerly flow aloft, and with pockets of strong daytime heating helping to steepen low-level lapse rates. This will promote a risk of gusty/damaging winds in the strongest cells. As the activity spreads eastward into the Plains, further intensification is possible with a few cells continuing a risk of gusty winds and hail during the evening. ...Southeast AZ... Afternoon thunderstorms have been occurring daily over southeast AZ, with isolated strong cells capable of gusty winds. Today will be similar as daytime heating dewpoints in the 60s promote storms over the higher terrain that track slowly northwestward during the late afternoon and early evening. Read more