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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0210 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z The area delineating potential for isolated dry thunderstorms has been expanded into portions of southwest Montana. The latest HREF guidance indicates potential for isolated thunderstorms into this region amid fuels that remain receptive to large-fire spread. Brief/localized elevated wind/RH conditions may also occur across parts of the northwestern Great Basin, as westerly surface winds develop during the peak heating of the late afternoon/early evening time frame. Otherwise, the previous forecast remains on track. See the discussion below for more details. ..Karstens.. 07/22/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Mon Jul 22 2024/ ...Synopsis... The upper trough over the Northwest is forecast to remain mostly stationary as the adjacent ridge over the Rockies begins to weaken and shift to the east. Stronger flow aloft will gradually overspread the Northwest and northern Rockies through the week. Isolated dry thunderstorms and gusty downslope winds will promote elevated fire-weather potential D2/Tuesday. ...Northwest and Northern Rockies... With the upper trough over the Northwest expected to remain fairly stationary, lingering mid-level moisture and weak ascent will continue to support mid-level destabilization and thunderstorms D2/Tuesday afternoon. Very warm surface temperatures and fast storm speeds will again favor mostly dry storms with the potential for lightning ignitions in dry fuels. Forcing for ascent should be slightly less than previous days, casting some uncertainty on storm coverage. However, at least isolated dry thunderstorms are possible over parts of eastern WA/OR and into western ID. West/southwest flow aloft is forecast to increase over the northern Rockies and Cascade Gaps ahead of the trough. This may promote several hours of gusty downslope winds across parts of eastern ID and western MT. Model guidance shows surface winds of 15-25 mph overlapping with RH values below 20%. This, along with the increase in lightning, will support the potential for elevated fire-weather conditions D2/Tuesday afternoon. ...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 0210 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z The area delineating potential for isolated dry thunderstorms has been expanded into portions of southwest Montana. The latest HREF guidance indicates potential for isolated thunderstorms into this region amid fuels that remain receptive to large-fire spread. Brief/localized elevated wind/RH conditions may also occur across parts of the northwestern Great Basin, as westerly surface winds develop during the peak heating of the late afternoon/early evening time frame. Otherwise, the previous forecast remains on track. See the discussion below for more details. ..Karstens.. 07/22/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Mon Jul 22 2024/ ...Synopsis... The upper trough over the Northwest is forecast to remain mostly stationary as the adjacent ridge over the Rockies begins to weaken and shift to the east. Stronger flow aloft will gradually overspread the Northwest and northern Rockies through the week. Isolated dry thunderstorms and gusty downslope winds will promote elevated fire-weather potential D2/Tuesday. ...Northwest and Northern Rockies... With the upper trough over the Northwest expected to remain fairly stationary, lingering mid-level moisture and weak ascent will continue to support mid-level destabilization and thunderstorms D2/Tuesday afternoon. Very warm surface temperatures and fast storm speeds will again favor mostly dry storms with the potential for lightning ignitions in dry fuels. Forcing for ascent should be slightly less than previous days, casting some uncertainty on storm coverage. However, at least isolated dry thunderstorms are possible over parts of eastern WA/OR and into western ID. West/southwest flow aloft is forecast to increase over the northern Rockies and Cascade Gaps ahead of the trough. This may promote several hours of gusty downslope winds across parts of eastern ID and western MT. Model guidance shows surface winds of 15-25 mph overlapping with RH values below 20%. This, along with the increase in lightning, will support the potential for elevated fire-weather conditions D2/Tuesday afternoon. ...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 0210 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z The area delineating potential for isolated dry thunderstorms has been expanded into portions of southwest Montana. The latest HREF guidance indicates potential for isolated thunderstorms into this region amid fuels that remain receptive to large-fire spread. Brief/localized elevated wind/RH conditions may also occur across parts of the northwestern Great Basin, as westerly surface winds develop during the peak heating of the late afternoon/early evening time frame. Otherwise, the previous forecast remains on track. See the discussion below for more details. ..Karstens.. 07/22/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Mon Jul 22 2024/ ...Synopsis... The upper trough over the Northwest is forecast to remain mostly stationary as the adjacent ridge over the Rockies begins to weaken and shift to the east. Stronger flow aloft will gradually overspread the Northwest and northern Rockies through the week. Isolated dry thunderstorms and gusty downslope winds will promote elevated fire-weather potential D2/Tuesday. ...Northwest and Northern Rockies... With the upper trough over the Northwest expected to remain fairly stationary, lingering mid-level moisture and weak ascent will continue to support mid-level destabilization and thunderstorms D2/Tuesday afternoon. Very warm surface temperatures and fast storm speeds will again favor mostly dry storms with the potential for lightning ignitions in dry fuels. Forcing for ascent should be slightly less than previous days, casting some uncertainty on storm coverage. However, at least isolated dry thunderstorms are possible over parts of eastern WA/OR and into western ID. West/southwest flow aloft is forecast to increase over the northern Rockies and Cascade Gaps ahead of the trough. This may promote several hours of gusty downslope winds across parts of eastern ID and western MT. Model guidance shows surface winds of 15-25 mph overlapping with RH values below 20%. This, along with the increase in lightning, will support the potential for elevated fire-weather conditions D2/Tuesday afternoon. ...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 0210 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z The area delineating potential for isolated dry thunderstorms has been expanded into portions of southwest Montana. The latest HREF guidance indicates potential for isolated thunderstorms into this region amid fuels that remain receptive to large-fire spread. Brief/localized elevated wind/RH conditions may also occur across parts of the northwestern Great Basin, as westerly surface winds develop during the peak heating of the late afternoon/early evening time frame. Otherwise, the previous forecast remains on track. See the discussion below for more details. ..Karstens.. 07/22/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Mon Jul 22 2024/ ...Synopsis... The upper trough over the Northwest is forecast to remain mostly stationary as the adjacent ridge over the Rockies begins to weaken and shift to the east. Stronger flow aloft will gradually overspread the Northwest and northern Rockies through the week. Isolated dry thunderstorms and gusty downslope winds will promote elevated fire-weather potential D2/Tuesday. ...Northwest and Northern Rockies... With the upper trough over the Northwest expected to remain fairly stationary, lingering mid-level moisture and weak ascent will continue to support mid-level destabilization and thunderstorms D2/Tuesday afternoon. Very warm surface temperatures and fast storm speeds will again favor mostly dry storms with the potential for lightning ignitions in dry fuels. Forcing for ascent should be slightly less than previous days, casting some uncertainty on storm coverage. However, at least isolated dry thunderstorms are possible over parts of eastern WA/OR and into western ID. West/southwest flow aloft is forecast to increase over the northern Rockies and Cascade Gaps ahead of the trough. This may promote several hours of gusty downslope winds across parts of eastern ID and western MT. Model guidance shows surface winds of 15-25 mph overlapping with RH values below 20%. This, along with the increase in lightning, will support the potential for elevated fire-weather conditions D2/Tuesday afternoon. ...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 0210 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z The area delineating potential for isolated dry thunderstorms has been expanded into portions of southwest Montana. The latest HREF guidance indicates potential for isolated thunderstorms into this region amid fuels that remain receptive to large-fire spread. Brief/localized elevated wind/RH conditions may also occur across parts of the northwestern Great Basin, as westerly surface winds develop during the peak heating of the late afternoon/early evening time frame. Otherwise, the previous forecast remains on track. See the discussion below for more details. ..Karstens.. 07/22/2024 .PREV DISCUSSION... /ISSUED 0156 AM CDT Mon Jul 22 2024/ ...Synopsis... The upper trough over the Northwest is forecast to remain mostly stationary as the adjacent ridge over the Rockies begins to weaken and shift to the east. Stronger flow aloft will gradually overspread the Northwest and northern Rockies through the week. Isolated dry thunderstorms and gusty downslope winds will promote elevated fire-weather potential D2/Tuesday. ...Northwest and Northern Rockies... With the upper trough over the Northwest expected to remain fairly stationary, lingering mid-level moisture and weak ascent will continue to support mid-level destabilization and thunderstorms D2/Tuesday afternoon. Very warm surface temperatures and fast storm speeds will again favor mostly dry storms with the potential for lightning ignitions in dry fuels. Forcing for ascent should be slightly less than previous days, casting some uncertainty on storm coverage. However, at least isolated dry thunderstorms are possible over parts of eastern WA/OR and into western ID. West/southwest flow aloft is forecast to increase over the northern Rockies and Cascade Gaps ahead of the trough. This may promote several hours of gusty downslope winds across parts of eastern ID and western MT. Model guidance shows surface winds of 15-25 mph overlapping with RH values below 20%. This, along with the increase in lightning, will support the potential for elevated fire-weather conditions D2/Tuesday afternoon. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

Water conservation guidelines were issued in Somerset while local dairies are producing less milk due to drought. Prohibited activities include watering lawns and gardens, washing paved surfaces and vehicles, watering golf courses, operating fountains and reflecting pools, filling swimming pools, and serving water in restaurants unless requested by the customer. Daily American (PA), July 22, 2024.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Tuesday. ...Discussion... The stagnant upper pattern which has prevailed over the U.S. for the last several days will remain generally unchanged Tuesday. Ridging will remain centered over the West, while troughing/cyclonic flow prevails once again over central and eastern portions of the country. One slight change will be a tightening of the height gradient over the East, as a western Atlantic ridge gradually expands westward. At the surface, a weak baroclinic zone will remain in place from the Mid-Atlantic region west-southwestward into Texas. Showers and thunderstorms are expected near and ahead of this front, coincident with afternoon destabilization. As the aforementioned tightening of the height gradient aloft allows some enhancement to the mid-level flow, and associated mid-level southwesterlies, shear sufficient for multicell organization is expected. However, with low-level flow to remain weak, any risk for severe weather -- largely in the form of gusty winds -- should remain local/isolated. Given the limited magnitude of the risk, the isolated coverage, and the broad area of potential (from the central Gulf Coast region to the Mid-Atlantic area), overall risk across this area is too low to introduce any severe risk areas at this time. Meanwhile in Arizona, storms are again expected to develop over the Rim during the afternoon, and then spread southwestward into the lower deserts given northeasterly winds at mid levels. At this time, however, will refrain from including a severe-weather risk area as coverage of convection remains uncertain given the apparent lack of any mid-level disturbance within the anticyclonic flow-field aloft. ..Goss.. 07/22/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Tuesday. ...Discussion... The stagnant upper pattern which has prevailed over the U.S. for the last several days will remain generally unchanged Tuesday. Ridging will remain centered over the West, while troughing/cyclonic flow prevails once again over central and eastern portions of the country. One slight change will be a tightening of the height gradient over the East, as a western Atlantic ridge gradually expands westward. At the surface, a weak baroclinic zone will remain in place from the Mid-Atlantic region west-southwestward into Texas. Showers and thunderstorms are expected near and ahead of this front, coincident with afternoon destabilization. As the aforementioned tightening of the height gradient aloft allows some enhancement to the mid-level flow, and associated mid-level southwesterlies, shear sufficient for multicell organization is expected. However, with low-level flow to remain weak, any risk for severe weather -- largely in the form of gusty winds -- should remain local/isolated. Given the limited magnitude of the risk, the isolated coverage, and the broad area of potential (from the central Gulf Coast region to the Mid-Atlantic area), overall risk across this area is too low to introduce any severe risk areas at this time. Meanwhile in Arizona, storms are again expected to develop over the Rim during the afternoon, and then spread southwestward into the lower deserts given northeasterly winds at mid levels. At this time, however, will refrain from including a severe-weather risk area as coverage of convection remains uncertain given the apparent lack of any mid-level disturbance within the anticyclonic flow-field aloft. ..Goss.. 07/22/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Tuesday. ...Discussion... The stagnant upper pattern which has prevailed over the U.S. for the last several days will remain generally unchanged Tuesday. Ridging will remain centered over the West, while troughing/cyclonic flow prevails once again over central and eastern portions of the country. One slight change will be a tightening of the height gradient over the East, as a western Atlantic ridge gradually expands westward. At the surface, a weak baroclinic zone will remain in place from the Mid-Atlantic region west-southwestward into Texas. Showers and thunderstorms are expected near and ahead of this front, coincident with afternoon destabilization. As the aforementioned tightening of the height gradient aloft allows some enhancement to the mid-level flow, and associated mid-level southwesterlies, shear sufficient for multicell organization is expected. However, with low-level flow to remain weak, any risk for severe weather -- largely in the form of gusty winds -- should remain local/isolated. Given the limited magnitude of the risk, the isolated coverage, and the broad area of potential (from the central Gulf Coast region to the Mid-Atlantic area), overall risk across this area is too low to introduce any severe risk areas at this time. Meanwhile in Arizona, storms are again expected to develop over the Rim during the afternoon, and then spread southwestward into the lower deserts given northeasterly winds at mid levels. At this time, however, will refrain from including a severe-weather risk area as coverage of convection remains uncertain given the apparent lack of any mid-level disturbance within the anticyclonic flow-field aloft. ..Goss.. 07/22/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Tuesday. ...Discussion... The stagnant upper pattern which has prevailed over the U.S. for the last several days will remain generally unchanged Tuesday. Ridging will remain centered over the West, while troughing/cyclonic flow prevails once again over central and eastern portions of the country. One slight change will be a tightening of the height gradient over the East, as a western Atlantic ridge gradually expands westward. At the surface, a weak baroclinic zone will remain in place from the Mid-Atlantic region west-southwestward into Texas. Showers and thunderstorms are expected near and ahead of this front, coincident with afternoon destabilization. As the aforementioned tightening of the height gradient aloft allows some enhancement to the mid-level flow, and associated mid-level southwesterlies, shear sufficient for multicell organization is expected. However, with low-level flow to remain weak, any risk for severe weather -- largely in the form of gusty winds -- should remain local/isolated. Given the limited magnitude of the risk, the isolated coverage, and the broad area of potential (from the central Gulf Coast region to the Mid-Atlantic area), overall risk across this area is too low to introduce any severe risk areas at this time. Meanwhile in Arizona, storms are again expected to develop over the Rim during the afternoon, and then spread southwestward into the lower deserts given northeasterly winds at mid levels. At this time, however, will refrain from including a severe-weather risk area as coverage of convection remains uncertain given the apparent lack of any mid-level disturbance within the anticyclonic flow-field aloft. ..Goss.. 07/22/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Tuesday. ...Discussion... The stagnant upper pattern which has prevailed over the U.S. for the last several days will remain generally unchanged Tuesday. Ridging will remain centered over the West, while troughing/cyclonic flow prevails once again over central and eastern portions of the country. One slight change will be a tightening of the height gradient over the East, as a western Atlantic ridge gradually expands westward. At the surface, a weak baroclinic zone will remain in place from the Mid-Atlantic region west-southwestward into Texas. Showers and thunderstorms are expected near and ahead of this front, coincident with afternoon destabilization. As the aforementioned tightening of the height gradient aloft allows some enhancement to the mid-level flow, and associated mid-level southwesterlies, shear sufficient for multicell organization is expected. However, with low-level flow to remain weak, any risk for severe weather -- largely in the form of gusty winds -- should remain local/isolated. Given the limited magnitude of the risk, the isolated coverage, and the broad area of potential (from the central Gulf Coast region to the Mid-Atlantic area), overall risk across this area is too low to introduce any severe risk areas at this time. Meanwhile in Arizona, storms are again expected to develop over the Rim during the afternoon, and then spread southwestward into the lower deserts given northeasterly winds at mid levels. At this time, however, will refrain from including a severe-weather risk area as coverage of convection remains uncertain given the apparent lack of any mid-level disturbance within the anticyclonic flow-field aloft. ..Goss.. 07/22/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Tuesday. ...Discussion... The stagnant upper pattern which has prevailed over the U.S. for the last several days will remain generally unchanged Tuesday. Ridging will remain centered over the West, while troughing/cyclonic flow prevails once again over central and eastern portions of the country. One slight change will be a tightening of the height gradient over the East, as a western Atlantic ridge gradually expands westward. At the surface, a weak baroclinic zone will remain in place from the Mid-Atlantic region west-southwestward into Texas. Showers and thunderstorms are expected near and ahead of this front, coincident with afternoon destabilization. As the aforementioned tightening of the height gradient aloft allows some enhancement to the mid-level flow, and associated mid-level southwesterlies, shear sufficient for multicell organization is expected. However, with low-level flow to remain weak, any risk for severe weather -- largely in the form of gusty winds -- should remain local/isolated. Given the limited magnitude of the risk, the isolated coverage, and the broad area of potential (from the central Gulf Coast region to the Mid-Atlantic area), overall risk across this area is too low to introduce any severe risk areas at this time. Meanwhile in Arizona, storms are again expected to develop over the Rim during the afternoon, and then spread southwestward into the lower deserts given northeasterly winds at mid levels. At this time, however, will refrain from including a severe-weather risk area as coverage of convection remains uncertain given the apparent lack of any mid-level disturbance within the anticyclonic flow-field aloft. ..Goss.. 07/22/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Tuesday. ...Discussion... The stagnant upper pattern which has prevailed over the U.S. for the last several days will remain generally unchanged Tuesday. Ridging will remain centered over the West, while troughing/cyclonic flow prevails once again over central and eastern portions of the country. One slight change will be a tightening of the height gradient over the East, as a western Atlantic ridge gradually expands westward. At the surface, a weak baroclinic zone will remain in place from the Mid-Atlantic region west-southwestward into Texas. Showers and thunderstorms are expected near and ahead of this front, coincident with afternoon destabilization. As the aforementioned tightening of the height gradient aloft allows some enhancement to the mid-level flow, and associated mid-level southwesterlies, shear sufficient for multicell organization is expected. However, with low-level flow to remain weak, any risk for severe weather -- largely in the form of gusty winds -- should remain local/isolated. Given the limited magnitude of the risk, the isolated coverage, and the broad area of potential (from the central Gulf Coast region to the Mid-Atlantic area), overall risk across this area is too low to introduce any severe risk areas at this time. Meanwhile in Arizona, storms are again expected to develop over the Rim during the afternoon, and then spread southwestward into the lower deserts given northeasterly winds at mid levels. At this time, however, will refrain from including a severe-weather risk area as coverage of convection remains uncertain given the apparent lack of any mid-level disturbance within the anticyclonic flow-field aloft. ..Goss.. 07/22/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Tuesday. ...Discussion... The stagnant upper pattern which has prevailed over the U.S. for the last several days will remain generally unchanged Tuesday. Ridging will remain centered over the West, while troughing/cyclonic flow prevails once again over central and eastern portions of the country. One slight change will be a tightening of the height gradient over the East, as a western Atlantic ridge gradually expands westward. At the surface, a weak baroclinic zone will remain in place from the Mid-Atlantic region west-southwestward into Texas. Showers and thunderstorms are expected near and ahead of this front, coincident with afternoon destabilization. As the aforementioned tightening of the height gradient aloft allows some enhancement to the mid-level flow, and associated mid-level southwesterlies, shear sufficient for multicell organization is expected. However, with low-level flow to remain weak, any risk for severe weather -- largely in the form of gusty winds -- should remain local/isolated. Given the limited magnitude of the risk, the isolated coverage, and the broad area of potential (from the central Gulf Coast region to the Mid-Atlantic area), overall risk across this area is too low to introduce any severe risk areas at this time. Meanwhile in Arizona, storms are again expected to develop over the Rim during the afternoon, and then spread southwestward into the lower deserts given northeasterly winds at mid levels. At this time, however, will refrain from including a severe-weather risk area as coverage of convection remains uncertain given the apparent lack of any mid-level disturbance within the anticyclonic flow-field aloft. ..Goss.. 07/22/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Mon Jul 22 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Tuesday. ...Discussion... The stagnant upper pattern which has prevailed over the U.S. for the last several days will remain generally unchanged Tuesday. Ridging will remain centered over the West, while troughing/cyclonic flow prevails once again over central and eastern portions of the country. One slight change will be a tightening of the height gradient over the East, as a western Atlantic ridge gradually expands westward. At the surface, a weak baroclinic zone will remain in place from the Mid-Atlantic region west-southwestward into Texas. Showers and thunderstorms are expected near and ahead of this front, coincident with afternoon destabilization. As the aforementioned tightening of the height gradient aloft allows some enhancement to the mid-level flow, and associated mid-level southwesterlies, shear sufficient for multicell organization is expected. However, with low-level flow to remain weak, any risk for severe weather -- largely in the form of gusty winds -- should remain local/isolated. Given the limited magnitude of the risk, the isolated coverage, and the broad area of potential (from the central Gulf Coast region to the Mid-Atlantic area), overall risk across this area is too low to introduce any severe risk areas at this time. Meanwhile in Arizona, storms are again expected to develop over the Rim during the afternoon, and then spread southwestward into the lower deserts given northeasterly winds at mid levels. At this time, however, will refrain from including a severe-weather risk area as coverage of convection remains uncertain given the apparent lack of any mid-level disturbance within the anticyclonic flow-field aloft. ..Goss.. 07/22/2024 Read more

198
ABPZ20 KNHC 221719
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Mon Jul 22 2024

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

Central and Western East Pacific:
A tropical wave located several hundred miles south-southwest of the
southern tip of the Baja California Peninsula is producing
disorganized shower and thunderstorm activity. Environmental
conditions could become a little more conducive for some gradual
development of this system over the next several days while it moves
westward to west-northwestward at 10 to 15 mph across the central
and western portions of the basin.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...30 percent.

Offshore Southwestern Mexico:
Disorganized showers and thunderstorms located a few hundred miles
south-southwest of Acapulco, Mexico are associated with a tropical
wave. Environmental conditions could support slight development
over the next couple of days as the system moves slowly
west-northwestward or northwestward, remaining offshore of
southwestern Mexico.
*Formation chance through 48 hours...low...10 percent.
*Formation chance through 7 days...low...10 percent.

$$
Forecaster Hagen/Brown

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Mon Jul 22 2024 Valid 221630Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF THE MID-ATLANTIC REGION....AND WESTERN ARIZONA TO THE LOWER COLORADO RIVER VALLEY... ...SUMMARY... Isolated severe thunderstorms will be possible this afternoon and early evening over portions of the mid-Atlantic region, as well as western Arizona to the lower Colorado River Valley. ...Mid-Atlantic states... A narrow ribbon of slightly enhanced southwesterly 500-mb flow will remain across NC/Delmarva to the southeast of a broad/weak mid-level trough centered over the Great Lakes southwestward through the Ozarks. Although large-scale forcing will be modest, a seasonably moist airmass (14-16 g/kg lowest 100-mb mean mixing ratios per 12 UTC area raobs) will gradually destabilize through the mid afternoon. Midday visible satellite imagery shows the initial stages of a building cumulus field across the Carolinas northward into eastern VA. Widely scattered to scattered thunderstorms are forecast to develop this afternoon within the moderately unstable airmass. Some strengthening in south-southwesterly 850-mb flow is progged by models later this afternoon into the early evening. A few of the stronger storms may pose a localized risk for damaging gusts (45-60 mph). If a transient supercell can develop (primarily 21-01z), a brief tornado is possible. This activity will likely diminish by mid-late evening owing to nocturnal stabilization. ...Western AZ/lower CO River Valley... Widely scattered thunderstorms are forecast to develop later this afternoon/evening as surface temperatures soar into the 100s. Although flow will be weak due to proximity to the mid- to upper-level ridge, large surface temperature-dewpoint depressions (around 50 deg F) will favor evaporative cooled downdrafts with the more robust thunderstorm cores. A few severe gusts (60-70 mph) are possible before this activity wanes by mid evening. ...Southeast New England... Model guidance indicates increased shower/thunderstorm potential late tonight (08-12 UTC) as a strengthening LLJ shifts northeastward from the Mid-Atlantic coast to near the continental shelf/deep Atlantic waters off the southeast New England coast. The latest models generally indicate meager to no surface-based buoyancy penetrating the coast, thus precluding low-severe probabilities this outlook update. ..Smith/Barnes.. 07/22/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Mon Jul 22 2024 Valid 221630Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF THE MID-ATLANTIC REGION....AND WESTERN ARIZONA TO THE LOWER COLORADO RIVER VALLEY... ...SUMMARY... Isolated severe thunderstorms will be possible this afternoon and early evening over portions of the mid-Atlantic region, as well as western Arizona to the lower Colorado River Valley. ...Mid-Atlantic states... A narrow ribbon of slightly enhanced southwesterly 500-mb flow will remain across NC/Delmarva to the southeast of a broad/weak mid-level trough centered over the Great Lakes southwestward through the Ozarks. Although large-scale forcing will be modest, a seasonably moist airmass (14-16 g/kg lowest 100-mb mean mixing ratios per 12 UTC area raobs) will gradually destabilize through the mid afternoon. Midday visible satellite imagery shows the initial stages of a building cumulus field across the Carolinas northward into eastern VA. Widely scattered to scattered thunderstorms are forecast to develop this afternoon within the moderately unstable airmass. Some strengthening in south-southwesterly 850-mb flow is progged by models later this afternoon into the early evening. A few of the stronger storms may pose a localized risk for damaging gusts (45-60 mph). If a transient supercell can develop (primarily 21-01z), a brief tornado is possible. This activity will likely diminish by mid-late evening owing to nocturnal stabilization. ...Western AZ/lower CO River Valley... Widely scattered thunderstorms are forecast to develop later this afternoon/evening as surface temperatures soar into the 100s. Although flow will be weak due to proximity to the mid- to upper-level ridge, large surface temperature-dewpoint depressions (around 50 deg F) will favor evaporative cooled downdrafts with the more robust thunderstorm cores. A few severe gusts (60-70 mph) are possible before this activity wanes by mid evening. ...Southeast New England... Model guidance indicates increased shower/thunderstorm potential late tonight (08-12 UTC) as a strengthening LLJ shifts northeastward from the Mid-Atlantic coast to near the continental shelf/deep Atlantic waters off the southeast New England coast. The latest models generally indicate meager to no surface-based buoyancy penetrating the coast, thus precluding low-severe probabilities this outlook update. ..Smith/Barnes.. 07/22/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Mon Jul 22 2024 Valid 221630Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF THE MID-ATLANTIC REGION....AND WESTERN ARIZONA TO THE LOWER COLORADO RIVER VALLEY... ...SUMMARY... Isolated severe thunderstorms will be possible this afternoon and early evening over portions of the mid-Atlantic region, as well as western Arizona to the lower Colorado River Valley. ...Mid-Atlantic states... A narrow ribbon of slightly enhanced southwesterly 500-mb flow will remain across NC/Delmarva to the southeast of a broad/weak mid-level trough centered over the Great Lakes southwestward through the Ozarks. Although large-scale forcing will be modest, a seasonably moist airmass (14-16 g/kg lowest 100-mb mean mixing ratios per 12 UTC area raobs) will gradually destabilize through the mid afternoon. Midday visible satellite imagery shows the initial stages of a building cumulus field across the Carolinas northward into eastern VA. Widely scattered to scattered thunderstorms are forecast to develop this afternoon within the moderately unstable airmass. Some strengthening in south-southwesterly 850-mb flow is progged by models later this afternoon into the early evening. A few of the stronger storms may pose a localized risk for damaging gusts (45-60 mph). If a transient supercell can develop (primarily 21-01z), a brief tornado is possible. This activity will likely diminish by mid-late evening owing to nocturnal stabilization. ...Western AZ/lower CO River Valley... Widely scattered thunderstorms are forecast to develop later this afternoon/evening as surface temperatures soar into the 100s. Although flow will be weak due to proximity to the mid- to upper-level ridge, large surface temperature-dewpoint depressions (around 50 deg F) will favor evaporative cooled downdrafts with the more robust thunderstorm cores. A few severe gusts (60-70 mph) are possible before this activity wanes by mid evening. ...Southeast New England... Model guidance indicates increased shower/thunderstorm potential late tonight (08-12 UTC) as a strengthening LLJ shifts northeastward from the Mid-Atlantic coast to near the continental shelf/deep Atlantic waters off the southeast New England coast. The latest models generally indicate meager to no surface-based buoyancy penetrating the coast, thus precluding low-severe probabilities this outlook update. ..Smith/Barnes.. 07/22/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Mon Jul 22 2024 Valid 221630Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF THE MID-ATLANTIC REGION....AND WESTERN ARIZONA TO THE LOWER COLORADO RIVER VALLEY... ...SUMMARY... Isolated severe thunderstorms will be possible this afternoon and early evening over portions of the mid-Atlantic region, as well as western Arizona to the lower Colorado River Valley. ...Mid-Atlantic states... A narrow ribbon of slightly enhanced southwesterly 500-mb flow will remain across NC/Delmarva to the southeast of a broad/weak mid-level trough centered over the Great Lakes southwestward through the Ozarks. Although large-scale forcing will be modest, a seasonably moist airmass (14-16 g/kg lowest 100-mb mean mixing ratios per 12 UTC area raobs) will gradually destabilize through the mid afternoon. Midday visible satellite imagery shows the initial stages of a building cumulus field across the Carolinas northward into eastern VA. Widely scattered to scattered thunderstorms are forecast to develop this afternoon within the moderately unstable airmass. Some strengthening in south-southwesterly 850-mb flow is progged by models later this afternoon into the early evening. A few of the stronger storms may pose a localized risk for damaging gusts (45-60 mph). If a transient supercell can develop (primarily 21-01z), a brief tornado is possible. This activity will likely diminish by mid-late evening owing to nocturnal stabilization. ...Western AZ/lower CO River Valley... Widely scattered thunderstorms are forecast to develop later this afternoon/evening as surface temperatures soar into the 100s. Although flow will be weak due to proximity to the mid- to upper-level ridge, large surface temperature-dewpoint depressions (around 50 deg F) will favor evaporative cooled downdrafts with the more robust thunderstorm cores. A few severe gusts (60-70 mph) are possible before this activity wanes by mid evening. ...Southeast New England... Model guidance indicates increased shower/thunderstorm potential late tonight (08-12 UTC) as a strengthening LLJ shifts northeastward from the Mid-Atlantic coast to near the continental shelf/deep Atlantic waters off the southeast New England coast. The latest models generally indicate meager to no surface-based buoyancy penetrating the coast, thus precluding low-severe probabilities this outlook update. ..Smith/Barnes.. 07/22/2024 Read more