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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook AMEND 1 NWS Storm Prediction Center Norman OK 0502 PM CDT Mon Jul 22 2024 Valid 222155Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTH DAKOTA AND NORTHWEST MINNESOTA...THE DESERT SOUTHWEST...AND THE MID-ATLANTIC/EASTERN NORTH CAROLINA... AMENDED FOR ADDITION OF HAIL/WIND PROBABILITIES IN NORTH DAKOTA AND NORTHWEST MINNESOTA ...SUMMARY... Isolated severe thunderstorms remain possible this afternoon and early evening over portions of North Dakota and northwest Minnesota, the mid-Atlantic region, as well as western Arizona to the lower Colorado River Valley. ...North Dakota/Northwest Minnesota... Isolated strong to severe thunderstorms are ongoing along a weak boundary/low-level confluence axis across parts of northeast ND and northwest MN. A few instances of large hail have already occurred. The presence of moderate to locally strong instability, along with marginally favorable deep-layer shear with modestly strengthening northwesterly winds at mid/upper levels, should support a continued threat for isolated severe hail and strong to damaging winds as this activity spreads slowly southward across ND and northwest MN late this afternoon and early evening. 5% severe hail/wind probabilities have been included with this amendment to account for this potential. See Mesoscale Discussion 1695 for additional details on the short-term severe threat across this region. ...Previous Discussions... ...20Z Discussion... Aside from minor line adjustments to affect recent/local trends, no appreciable changes appear to be needed, with respect to the ongoing forecast. Prior reasoning continues to reflect expectations regarding convective/severe risk through the end of the period. ...1630Z Discussion... ...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. ..Gleason.. 07/22/2024 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook AMEND 1 NWS Storm Prediction Center Norman OK 0502 PM CDT Mon Jul 22 2024 Valid 222155Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTH DAKOTA AND NORTHWEST MINNESOTA...THE DESERT SOUTHWEST...AND THE MID-ATLANTIC/EASTERN NORTH CAROLINA... AMENDED FOR ADDITION OF HAIL/WIND PROBABILITIES IN NORTH DAKOTA AND NORTHWEST MINNESOTA ...SUMMARY... Isolated severe thunderstorms remain possible this afternoon and early evening over portions of North Dakota and northwest Minnesota, the mid-Atlantic region, as well as western Arizona to the lower Colorado River Valley. ...North Dakota/Northwest Minnesota... Isolated strong to severe thunderstorms are ongoing along a weak boundary/low-level confluence axis across parts of northeast ND and northwest MN. A few instances of large hail have already occurred. The presence of moderate to locally strong instability, along with marginally favorable deep-layer shear with modestly strengthening northwesterly winds at mid/upper levels, should support a continued threat for isolated severe hail and strong to damaging winds as this activity spreads slowly southward across ND and northwest MN late this afternoon and early evening. 5% severe hail/wind probabilities have been included with this amendment to account for this potential. See Mesoscale Discussion 1695 for additional details on the short-term severe threat across this region. ...Previous Discussions... ...20Z Discussion... Aside from minor line adjustments to affect recent/local trends, no appreciable changes appear to be needed, with respect to the ongoing forecast. Prior reasoning continues to reflect expectations regarding convective/severe risk through the end of the period. ...1630Z Discussion... ...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. ..Gleason.. 07/22/2024 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook AMEND 1 NWS Storm Prediction Center Norman OK 0502 PM CDT Mon Jul 22 2024 Valid 222155Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTH DAKOTA AND NORTHWEST MINNESOTA...THE DESERT SOUTHWEST...AND THE MID-ATLANTIC/EASTERN NORTH CAROLINA... AMENDED FOR ADDITION OF HAIL/WIND PROBABILITIES IN NORTH DAKOTA AND NORTHWEST MINNESOTA ...SUMMARY... Isolated severe thunderstorms remain possible this afternoon and early evening over portions of North Dakota and northwest Minnesota, the mid-Atlantic region, as well as western Arizona to the lower Colorado River Valley. ...North Dakota/Northwest Minnesota... Isolated strong to severe thunderstorms are ongoing along a weak boundary/low-level confluence axis across parts of northeast ND and northwest MN. A few instances of large hail have already occurred. The presence of moderate to locally strong instability, along with marginally favorable deep-layer shear with modestly strengthening northwesterly winds at mid/upper levels, should support a continued threat for isolated severe hail and strong to damaging winds as this activity spreads slowly southward across ND and northwest MN late this afternoon and early evening. 5% severe hail/wind probabilities have been included with this amendment to account for this potential. See Mesoscale Discussion 1695 for additional details on the short-term severe threat across this region. ...Previous Discussions... ...20Z Discussion... Aside from minor line adjustments to affect recent/local trends, no appreciable changes appear to be needed, with respect to the ongoing forecast. Prior reasoning continues to reflect expectations regarding convective/severe risk through the end of the period. ...1630Z Discussion... ...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. ..Gleason.. 07/22/2024 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook AMEND 1 NWS Storm Prediction Center Norman OK 0502 PM CDT Mon Jul 22 2024 Valid 222155Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTH DAKOTA AND NORTHWEST MINNESOTA...THE DESERT SOUTHWEST...AND THE MID-ATLANTIC/EASTERN NORTH CAROLINA... AMENDED FOR ADDITION OF HAIL/WIND PROBABILITIES IN NORTH DAKOTA AND NORTHWEST MINNESOTA ...SUMMARY... Isolated severe thunderstorms remain possible this afternoon and early evening over portions of North Dakota and northwest Minnesota, the mid-Atlantic region, as well as western Arizona to the lower Colorado River Valley. ...North Dakota/Northwest Minnesota... Isolated strong to severe thunderstorms are ongoing along a weak boundary/low-level confluence axis across parts of northeast ND and northwest MN. A few instances of large hail have already occurred. The presence of moderate to locally strong instability, along with marginally favorable deep-layer shear with modestly strengthening northwesterly winds at mid/upper levels, should support a continued threat for isolated severe hail and strong to damaging winds as this activity spreads slowly southward across ND and northwest MN late this afternoon and early evening. 5% severe hail/wind probabilities have been included with this amendment to account for this potential. See Mesoscale Discussion 1695 for additional details on the short-term severe threat across this region. ...Previous Discussions... ...20Z Discussion... Aside from minor line adjustments to affect recent/local trends, no appreciable changes appear to be needed, with respect to the ongoing forecast. Prior reasoning continues to reflect expectations regarding convective/severe risk through the end of the period. ...1630Z Discussion... ...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. ..Gleason.. 07/22/2024 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0435 PM CDT Mon Jul 22 2024 Valid 241200Z - 301200Z An upper-level ridge positioned over the West will begin to break down as a mid-level trough enters the Pacific Northwest on D3/Wed and moves through the northern Rockies by D5/Fri. Another weak trough will likely develop in its wake before transitioning to a zonal mid-level flow pattern by early next week. At the surface, hot/dry conditions will persist in most areas of the West, with breezy conditions accompanying the passage of cold front across the northern Rockies. Otherwise, weak surface winds can be expected for most areas of the West into early next week. ...Wind/RH Concerns... Potential for at least elevated fire-weather conditions continues to be expected across parts of the Pacific Northwest and northern Rockies on D3/Wed through D5/Fri, as the mid-level trough traverses this region. Guidance remains consistent with highlighting the areas east of the Cascades on D3/Wed and D4/Thu, and minor expansions were made to the probabilities in this region. D4/Thu continues to show potential for critical fire-weather conditions, though spread among medium-range guidance precludes inclusion of 70% probabilities at this time. Diurnally driven downslope winds and low RH will likely emerge each day across portions of northern Montana, from D3/Wed through D5/Fri. 40% probabilities have been maintained or introduced to encompass this threat. Pre-frontal southerly winds and low RH may allow for briefly elevated conditions across parts of eastern Wyoming and western South Dakota on D4/Thu, but for now probabilities have not been introduced. ...Dry Lightning... The recent surge of sub-tropical moisture into the Pacific Northwest will continue to result in daily chances for thunderstorms and dry lightning potential. Areas on D3/Wed and D4/Thu have been expanded based on the latest guidance. Potential for scattered dry thunderstorms will exist on D3/Wed across portions of eastern Oregon as the trough enters the region, providing broad forcing for ascent and stronger deep-layer flow promoting faster storm motions and more organized storm structures. Confidence in this scenario remains a bit uncertain, but an upgrade may need to be considered in future outlooks. For D6/Sat and beyond, chances for dry thunderstorms will likely reemerge, though predictability of such features/areas is too low to introduce any probabilities. ..Karstens.. 07/22/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0435 PM CDT Mon Jul 22 2024 Valid 241200Z - 301200Z An upper-level ridge positioned over the West will begin to break down as a mid-level trough enters the Pacific Northwest on D3/Wed and moves through the northern Rockies by D5/Fri. Another weak trough will likely develop in its wake before transitioning to a zonal mid-level flow pattern by early next week. At the surface, hot/dry conditions will persist in most areas of the West, with breezy conditions accompanying the passage of cold front across the northern Rockies. Otherwise, weak surface winds can be expected for most areas of the West into early next week. ...Wind/RH Concerns... Potential for at least elevated fire-weather conditions continues to be expected across parts of the Pacific Northwest and northern Rockies on D3/Wed through D5/Fri, as the mid-level trough traverses this region. Guidance remains consistent with highlighting the areas east of the Cascades on D3/Wed and D4/Thu, and minor expansions were made to the probabilities in this region. D4/Thu continues to show potential for critical fire-weather conditions, though spread among medium-range guidance precludes inclusion of 70% probabilities at this time. Diurnally driven downslope winds and low RH will likely emerge each day across portions of northern Montana, from D3/Wed through D5/Fri. 40% probabilities have been maintained or introduced to encompass this threat. Pre-frontal southerly winds and low RH may allow for briefly elevated conditions across parts of eastern Wyoming and western South Dakota on D4/Thu, but for now probabilities have not been introduced. ...Dry Lightning... The recent surge of sub-tropical moisture into the Pacific Northwest will continue to result in daily chances for thunderstorms and dry lightning potential. Areas on D3/Wed and D4/Thu have been expanded based on the latest guidance. Potential for scattered dry thunderstorms will exist on D3/Wed across portions of eastern Oregon as the trough enters the region, providing broad forcing for ascent and stronger deep-layer flow promoting faster storm motions and more organized storm structures. Confidence in this scenario remains a bit uncertain, but an upgrade may need to be considered in future outlooks. For D6/Sat and beyond, chances for dry thunderstorms will likely reemerge, though predictability of such features/areas is too low to introduce any probabilities. ..Karstens.. 07/22/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0435 PM CDT Mon Jul 22 2024 Valid 241200Z - 301200Z An upper-level ridge positioned over the West will begin to break down as a mid-level trough enters the Pacific Northwest on D3/Wed and moves through the northern Rockies by D5/Fri. Another weak trough will likely develop in its wake before transitioning to a zonal mid-level flow pattern by early next week. At the surface, hot/dry conditions will persist in most areas of the West, with breezy conditions accompanying the passage of cold front across the northern Rockies. Otherwise, weak surface winds can be expected for most areas of the West into early next week. ...Wind/RH Concerns... Potential for at least elevated fire-weather conditions continues to be expected across parts of the Pacific Northwest and northern Rockies on D3/Wed through D5/Fri, as the mid-level trough traverses this region. Guidance remains consistent with highlighting the areas east of the Cascades on D3/Wed and D4/Thu, and minor expansions were made to the probabilities in this region. D4/Thu continues to show potential for critical fire-weather conditions, though spread among medium-range guidance precludes inclusion of 70% probabilities at this time. Diurnally driven downslope winds and low RH will likely emerge each day across portions of northern Montana, from D3/Wed through D5/Fri. 40% probabilities have been maintained or introduced to encompass this threat. Pre-frontal southerly winds and low RH may allow for briefly elevated conditions across parts of eastern Wyoming and western South Dakota on D4/Thu, but for now probabilities have not been introduced. ...Dry Lightning... The recent surge of sub-tropical moisture into the Pacific Northwest will continue to result in daily chances for thunderstorms and dry lightning potential. Areas on D3/Wed and D4/Thu have been expanded based on the latest guidance. Potential for scattered dry thunderstorms will exist on D3/Wed across portions of eastern Oregon as the trough enters the region, providing broad forcing for ascent and stronger deep-layer flow promoting faster storm motions and more organized storm structures. Confidence in this scenario remains a bit uncertain, but an upgrade may need to be considered in future outlooks. For D6/Sat and beyond, chances for dry thunderstorms will likely reemerge, though predictability of such features/areas is too low to introduce any probabilities. ..Karstens.. 07/22/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0435 PM CDT Mon Jul 22 2024 Valid 241200Z - 301200Z An upper-level ridge positioned over the West will begin to break down as a mid-level trough enters the Pacific Northwest on D3/Wed and moves through the northern Rockies by D5/Fri. Another weak trough will likely develop in its wake before transitioning to a zonal mid-level flow pattern by early next week. At the surface, hot/dry conditions will persist in most areas of the West, with breezy conditions accompanying the passage of cold front across the northern Rockies. Otherwise, weak surface winds can be expected for most areas of the West into early next week. ...Wind/RH Concerns... Potential for at least elevated fire-weather conditions continues to be expected across parts of the Pacific Northwest and northern Rockies on D3/Wed through D5/Fri, as the mid-level trough traverses this region. Guidance remains consistent with highlighting the areas east of the Cascades on D3/Wed and D4/Thu, and minor expansions were made to the probabilities in this region. D4/Thu continues to show potential for critical fire-weather conditions, though spread among medium-range guidance precludes inclusion of 70% probabilities at this time. Diurnally driven downslope winds and low RH will likely emerge each day across portions of northern Montana, from D3/Wed through D5/Fri. 40% probabilities have been maintained or introduced to encompass this threat. Pre-frontal southerly winds and low RH may allow for briefly elevated conditions across parts of eastern Wyoming and western South Dakota on D4/Thu, but for now probabilities have not been introduced. ...Dry Lightning... The recent surge of sub-tropical moisture into the Pacific Northwest will continue to result in daily chances for thunderstorms and dry lightning potential. Areas on D3/Wed and D4/Thu have been expanded based on the latest guidance. Potential for scattered dry thunderstorms will exist on D3/Wed across portions of eastern Oregon as the trough enters the region, providing broad forcing for ascent and stronger deep-layer flow promoting faster storm motions and more organized storm structures. Confidence in this scenario remains a bit uncertain, but an upgrade may need to be considered in future outlooks. For D6/Sat and beyond, chances for dry thunderstorms will likely reemerge, though predictability of such features/areas is too low to introduce any probabilities. ..Karstens.. 07/22/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0435 PM CDT Mon Jul 22 2024 Valid 241200Z - 301200Z An upper-level ridge positioned over the West will begin to break down as a mid-level trough enters the Pacific Northwest on D3/Wed and moves through the northern Rockies by D5/Fri. Another weak trough will likely develop in its wake before transitioning to a zonal mid-level flow pattern by early next week. At the surface, hot/dry conditions will persist in most areas of the West, with breezy conditions accompanying the passage of cold front across the northern Rockies. Otherwise, weak surface winds can be expected for most areas of the West into early next week. ...Wind/RH Concerns... Potential for at least elevated fire-weather conditions continues to be expected across parts of the Pacific Northwest and northern Rockies on D3/Wed through D5/Fri, as the mid-level trough traverses this region. Guidance remains consistent with highlighting the areas east of the Cascades on D3/Wed and D4/Thu, and minor expansions were made to the probabilities in this region. D4/Thu continues to show potential for critical fire-weather conditions, though spread among medium-range guidance precludes inclusion of 70% probabilities at this time. Diurnally driven downslope winds and low RH will likely emerge each day across portions of northern Montana, from D3/Wed through D5/Fri. 40% probabilities have been maintained or introduced to encompass this threat. Pre-frontal southerly winds and low RH may allow for briefly elevated conditions across parts of eastern Wyoming and western South Dakota on D4/Thu, but for now probabilities have not been introduced. ...Dry Lightning... The recent surge of sub-tropical moisture into the Pacific Northwest will continue to result in daily chances for thunderstorms and dry lightning potential. Areas on D3/Wed and D4/Thu have been expanded based on the latest guidance. Potential for scattered dry thunderstorms will exist on D3/Wed across portions of eastern Oregon as the trough enters the region, providing broad forcing for ascent and stronger deep-layer flow promoting faster storm motions and more organized storm structures. Confidence in this scenario remains a bit uncertain, but an upgrade may need to be considered in future outlooks. For D6/Sat and beyond, chances for dry thunderstorms will likely reemerge, though predictability of such features/areas is too low to introduce any probabilities. ..Karstens.. 07/22/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0435 PM CDT Mon Jul 22 2024 Valid 241200Z - 301200Z An upper-level ridge positioned over the West will begin to break down as a mid-level trough enters the Pacific Northwest on D3/Wed and moves through the northern Rockies by D5/Fri. Another weak trough will likely develop in its wake before transitioning to a zonal mid-level flow pattern by early next week. At the surface, hot/dry conditions will persist in most areas of the West, with breezy conditions accompanying the passage of cold front across the northern Rockies. Otherwise, weak surface winds can be expected for most areas of the West into early next week. ...Wind/RH Concerns... Potential for at least elevated fire-weather conditions continues to be expected across parts of the Pacific Northwest and northern Rockies on D3/Wed through D5/Fri, as the mid-level trough traverses this region. Guidance remains consistent with highlighting the areas east of the Cascades on D3/Wed and D4/Thu, and minor expansions were made to the probabilities in this region. D4/Thu continues to show potential for critical fire-weather conditions, though spread among medium-range guidance precludes inclusion of 70% probabilities at this time. Diurnally driven downslope winds and low RH will likely emerge each day across portions of northern Montana, from D3/Wed through D5/Fri. 40% probabilities have been maintained or introduced to encompass this threat. Pre-frontal southerly winds and low RH may allow for briefly elevated conditions across parts of eastern Wyoming and western South Dakota on D4/Thu, but for now probabilities have not been introduced. ...Dry Lightning... The recent surge of sub-tropical moisture into the Pacific Northwest will continue to result in daily chances for thunderstorms and dry lightning potential. Areas on D3/Wed and D4/Thu have been expanded based on the latest guidance. Potential for scattered dry thunderstorms will exist on D3/Wed across portions of eastern Oregon as the trough enters the region, providing broad forcing for ascent and stronger deep-layer flow promoting faster storm motions and more organized storm structures. Confidence in this scenario remains a bit uncertain, but an upgrade may need to be considered in future outlooks. For D6/Sat and beyond, chances for dry thunderstorms will likely reemerge, though predictability of such features/areas is too low to introduce any probabilities. ..Karstens.. 07/22/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0435 PM CDT Mon Jul 22 2024 Valid 241200Z - 301200Z An upper-level ridge positioned over the West will begin to break down as a mid-level trough enters the Pacific Northwest on D3/Wed and moves through the northern Rockies by D5/Fri. Another weak trough will likely develop in its wake before transitioning to a zonal mid-level flow pattern by early next week. At the surface, hot/dry conditions will persist in most areas of the West, with breezy conditions accompanying the passage of cold front across the northern Rockies. Otherwise, weak surface winds can be expected for most areas of the West into early next week. ...Wind/RH Concerns... Potential for at least elevated fire-weather conditions continues to be expected across parts of the Pacific Northwest and northern Rockies on D3/Wed through D5/Fri, as the mid-level trough traverses this region. Guidance remains consistent with highlighting the areas east of the Cascades on D3/Wed and D4/Thu, and minor expansions were made to the probabilities in this region. D4/Thu continues to show potential for critical fire-weather conditions, though spread among medium-range guidance precludes inclusion of 70% probabilities at this time. Diurnally driven downslope winds and low RH will likely emerge each day across portions of northern Montana, from D3/Wed through D5/Fri. 40% probabilities have been maintained or introduced to encompass this threat. Pre-frontal southerly winds and low RH may allow for briefly elevated conditions across parts of eastern Wyoming and western South Dakota on D4/Thu, but for now probabilities have not been introduced. ...Dry Lightning... The recent surge of sub-tropical moisture into the Pacific Northwest will continue to result in daily chances for thunderstorms and dry lightning potential. Areas on D3/Wed and D4/Thu have been expanded based on the latest guidance. Potential for scattered dry thunderstorms will exist on D3/Wed across portions of eastern Oregon as the trough enters the region, providing broad forcing for ascent and stronger deep-layer flow promoting faster storm motions and more organized storm structures. Confidence in this scenario remains a bit uncertain, but an upgrade may need to be considered in future outlooks. For D6/Sat and beyond, chances for dry thunderstorms will likely reemerge, though predictability of such features/areas is too low to introduce any probabilities. ..Karstens.. 07/22/2024 ...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 0235 PM CDT Mon Jul 22 2024 Valid 222000Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DESERT SOUTHWEST...AND PARTS OF THE MID-ATLANTIC/EASTERN NORTH CAROLINA... ...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. ...Discussion... Aside from minor line adjustments to affect recent/local trends, no appreciable changes appear to be needed, with respect to the ongoing forecast. Prior reasoning continues to reflect expectations regarding convective/severe risk through the end of the period. ..Goss.. 07/22/2024 .PREV DISCUSSION... /ISSUED 1127 AM CDT Mon Jul 22 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0235 PM CDT Mon Jul 22 2024 Valid 222000Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DESERT SOUTHWEST...AND PARTS OF THE MID-ATLANTIC/EASTERN NORTH CAROLINA... ...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. ...Discussion... Aside from minor line adjustments to affect recent/local trends, no appreciable changes appear to be needed, with respect to the ongoing forecast. Prior reasoning continues to reflect expectations regarding convective/severe risk through the end of the period. ..Goss.. 07/22/2024 .PREV DISCUSSION... /ISSUED 1127 AM CDT Mon Jul 22 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0235 PM CDT Mon Jul 22 2024 Valid 222000Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DESERT SOUTHWEST...AND PARTS OF THE MID-ATLANTIC/EASTERN NORTH CAROLINA... ...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. ...Discussion... Aside from minor line adjustments to affect recent/local trends, no appreciable changes appear to be needed, with respect to the ongoing forecast. Prior reasoning continues to reflect expectations regarding convective/severe risk through the end of the period. ..Goss.. 07/22/2024 .PREV DISCUSSION... /ISSUED 1127 AM CDT Mon Jul 22 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0235 PM CDT Mon Jul 22 2024 Valid 222000Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE DESERT SOUTHWEST...AND PARTS OF THE MID-ATLANTIC/EASTERN NORTH CAROLINA... ...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. ...Discussion... Aside from minor line adjustments to affect recent/local trends, no appreciable changes appear to be needed, with respect to the ongoing forecast. Prior reasoning continues to reflect expectations regarding convective/severe risk through the end of the period. ..Goss.. 07/22/2024 .PREV DISCUSSION... /ISSUED 1127 AM CDT Mon Jul 22 2024/ ...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. Read more

MD 1693 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR CENTRAL AND EASTERN NORTH CAROLINA
Mesoscale Discussion 1693 NWS Storm Prediction Center Norman OK 0132 PM CDT Mon Jul 22 2024 Areas affected...Central and eastern North Carolina Concerning...Severe potential...Watch unlikely Valid 221832Z - 222030Z Probability of Watch Issuance...20 percent SUMMARY...A few strong to severe thunderstorms are expected through late this afternoon across portions of central and eastern NC. Damaging wind gusts, and perhaps a tornado late this afternoon, will be possible. DISCUSSION...Latest visible satellite and radar imagery suggest an increase in moist convection is ongoing along a weakly convergent sea breeze and within subtle DCVA. This area is also under a belt of relatively stronger mid to upper level southwesterly flow, and near a moderate instability axis extending southwest to northeast. Dewpoints in the mid to upper 70s combined with temperatures in the mid to upper 80s are contributing to MLCAPE ~2000 J/kg. As destabilization continues through this afternoon, and effective shear remains around 30-35 kt, a few organized updrafts are anticipated. In addition, a modest increase in low-level flow late this afternoon near the northeastern NC coastline may result in some enhanced low-level helicity and the opportunity for a brief tornado. The main concern, however, will be damaging wind gusts via precipitation loading especially with any supercells that manage to develop and/or clusters contributing to deepening cold pools. Given the expected severe weather coverage, a WW is not anticipated at this time. ..Barnes/Smith.. 07/22/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...MHX...RAH...ILM...RNK... LAT...LON 34327849 34267878 34647918 35657920 36547882 36557626 36547582 36107566 35927570 35077655 34847709 34327849 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