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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Sat Aug 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FROM THE MID-ATLANTIC INTO NORTH CAROLINA...AND ACROSS PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ...SUMMARY... Thunderstorms, associated with a marginal severe threat, will be possible on Monday in parts of the Mid-Atlantic, North Carolina, and from the central to the northern High Plains. ...Mid-Atlantic/North Carolina... An upper-level trough will move slowly eastward across the southern and central Appalachians on Monday, as a cold front advances southeastward toward the middle Atlantic Coast. Surface dewpoints across most of the Mid-Atlantic into North Carolina are forecast to be in the 60s F, with 70+ surface dewpoints confined to the immediate Atlantic coast. As surface temperatures warm, a pocket of instability will likely develop near and ahead of the front, and in the post-frontal airmass. Scattered thunderstorms are expected to form within these areas as surface temperatures warm during the day. Although low-level lapse rates will become steep in many areas by afternoon, deep-layer shear is forecast to remain relatively weak. The instability could still be strong enough for a marginal severe threat. Isolated strong to severe wind gusts could occur near and around peak heating. ...Central to Northern High Plains... An upper-level ridge is forecast to move across the Central High Plains and northern Plains on Monday. An axis of instability will likely develop during the day to the west of the ridge, from eastern Colorado northward into eastern Montana and western North Dakota. Although large-scale ascent will be weak along this corridor, thunderstorms are expected to form in some areas due to topographical forcing in the central and northern Rockies. More isolated storms will be possible in the lower elevations of the central and northern High Plains. Forecast soundings across the central and northern High Plains have steep low to mid-level lapse rates and sufficient deep-layer shear for a marginal severe threat. Relatively large surface temperature-dewpoint spreads could enhance downdrafts associated with high-based storms. Hail could also accompany the stronger cells, especially further west near the higher terrain. ...Ark-La-Tex... North-northwesterly mid-level flow will be in place across the Ark-La-Tex on Monday. At the surface, a quasi-stationary front is forecast from northeast Texas into Louisiana, where surface dewpoints should be in the lower 70s F. As surface temperatures warm during the day, low-level lapse rates will become steep. This combined with moderate deep-layer shear may support an isolated severe threat. Although there is some uncertainty concerning convective coverage, the forecast environment should be enough for a few marginally severe storms. ..Broyles.. 08/17/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Sat Aug 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FROM THE MID-ATLANTIC INTO NORTH CAROLINA...AND ACROSS PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ...SUMMARY... Thunderstorms, associated with a marginal severe threat, will be possible on Monday in parts of the Mid-Atlantic, North Carolina, and from the central to the northern High Plains. ...Mid-Atlantic/North Carolina... An upper-level trough will move slowly eastward across the southern and central Appalachians on Monday, as a cold front advances southeastward toward the middle Atlantic Coast. Surface dewpoints across most of the Mid-Atlantic into North Carolina are forecast to be in the 60s F, with 70+ surface dewpoints confined to the immediate Atlantic coast. As surface temperatures warm, a pocket of instability will likely develop near and ahead of the front, and in the post-frontal airmass. Scattered thunderstorms are expected to form within these areas as surface temperatures warm during the day. Although low-level lapse rates will become steep in many areas by afternoon, deep-layer shear is forecast to remain relatively weak. The instability could still be strong enough for a marginal severe threat. Isolated strong to severe wind gusts could occur near and around peak heating. ...Central to Northern High Plains... An upper-level ridge is forecast to move across the Central High Plains and northern Plains on Monday. An axis of instability will likely develop during the day to the west of the ridge, from eastern Colorado northward into eastern Montana and western North Dakota. Although large-scale ascent will be weak along this corridor, thunderstorms are expected to form in some areas due to topographical forcing in the central and northern Rockies. More isolated storms will be possible in the lower elevations of the central and northern High Plains. Forecast soundings across the central and northern High Plains have steep low to mid-level lapse rates and sufficient deep-layer shear for a marginal severe threat. Relatively large surface temperature-dewpoint spreads could enhance downdrafts associated with high-based storms. Hail could also accompany the stronger cells, especially further west near the higher terrain. ...Ark-La-Tex... North-northwesterly mid-level flow will be in place across the Ark-La-Tex on Monday. At the surface, a quasi-stationary front is forecast from northeast Texas into Louisiana, where surface dewpoints should be in the lower 70s F. As surface temperatures warm during the day, low-level lapse rates will become steep. This combined with moderate deep-layer shear may support an isolated severe threat. Although there is some uncertainty concerning convective coverage, the forecast environment should be enough for a few marginally severe storms. ..Broyles.. 08/17/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Sat Aug 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FROM THE MID-ATLANTIC INTO NORTH CAROLINA...AND ACROSS PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ...SUMMARY... Thunderstorms, associated with a marginal severe threat, will be possible on Monday in parts of the Mid-Atlantic, North Carolina, and from the central to the northern High Plains. ...Mid-Atlantic/North Carolina... An upper-level trough will move slowly eastward across the southern and central Appalachians on Monday, as a cold front advances southeastward toward the middle Atlantic Coast. Surface dewpoints across most of the Mid-Atlantic into North Carolina are forecast to be in the 60s F, with 70+ surface dewpoints confined to the immediate Atlantic coast. As surface temperatures warm, a pocket of instability will likely develop near and ahead of the front, and in the post-frontal airmass. Scattered thunderstorms are expected to form within these areas as surface temperatures warm during the day. Although low-level lapse rates will become steep in many areas by afternoon, deep-layer shear is forecast to remain relatively weak. The instability could still be strong enough for a marginal severe threat. Isolated strong to severe wind gusts could occur near and around peak heating. ...Central to Northern High Plains... An upper-level ridge is forecast to move across the Central High Plains and northern Plains on Monday. An axis of instability will likely develop during the day to the west of the ridge, from eastern Colorado northward into eastern Montana and western North Dakota. Although large-scale ascent will be weak along this corridor, thunderstorms are expected to form in some areas due to topographical forcing in the central and northern Rockies. More isolated storms will be possible in the lower elevations of the central and northern High Plains. Forecast soundings across the central and northern High Plains have steep low to mid-level lapse rates and sufficient deep-layer shear for a marginal severe threat. Relatively large surface temperature-dewpoint spreads could enhance downdrafts associated with high-based storms. Hail could also accompany the stronger cells, especially further west near the higher terrain. ...Ark-La-Tex... North-northwesterly mid-level flow will be in place across the Ark-La-Tex on Monday. At the surface, a quasi-stationary front is forecast from northeast Texas into Louisiana, where surface dewpoints should be in the lower 70s F. As surface temperatures warm during the day, low-level lapse rates will become steep. This combined with moderate deep-layer shear may support an isolated severe threat. Although there is some uncertainty concerning convective coverage, the forecast environment should be enough for a few marginally severe storms. ..Broyles.. 08/17/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Sat Aug 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FROM THE MID-ATLANTIC INTO NORTH CAROLINA...AND ACROSS PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ...SUMMARY... Thunderstorms, associated with a marginal severe threat, will be possible on Monday in parts of the Mid-Atlantic, North Carolina, and from the central to the northern High Plains. ...Mid-Atlantic/North Carolina... An upper-level trough will move slowly eastward across the southern and central Appalachians on Monday, as a cold front advances southeastward toward the middle Atlantic Coast. Surface dewpoints across most of the Mid-Atlantic into North Carolina are forecast to be in the 60s F, with 70+ surface dewpoints confined to the immediate Atlantic coast. As surface temperatures warm, a pocket of instability will likely develop near and ahead of the front, and in the post-frontal airmass. Scattered thunderstorms are expected to form within these areas as surface temperatures warm during the day. Although low-level lapse rates will become steep in many areas by afternoon, deep-layer shear is forecast to remain relatively weak. The instability could still be strong enough for a marginal severe threat. Isolated strong to severe wind gusts could occur near and around peak heating. ...Central to Northern High Plains... An upper-level ridge is forecast to move across the Central High Plains and northern Plains on Monday. An axis of instability will likely develop during the day to the west of the ridge, from eastern Colorado northward into eastern Montana and western North Dakota. Although large-scale ascent will be weak along this corridor, thunderstorms are expected to form in some areas due to topographical forcing in the central and northern Rockies. More isolated storms will be possible in the lower elevations of the central and northern High Plains. Forecast soundings across the central and northern High Plains have steep low to mid-level lapse rates and sufficient deep-layer shear for a marginal severe threat. Relatively large surface temperature-dewpoint spreads could enhance downdrafts associated with high-based storms. Hail could also accompany the stronger cells, especially further west near the higher terrain. ...Ark-La-Tex... North-northwesterly mid-level flow will be in place across the Ark-La-Tex on Monday. At the surface, a quasi-stationary front is forecast from northeast Texas into Louisiana, where surface dewpoints should be in the lower 70s F. As surface temperatures warm during the day, low-level lapse rates will become steep. This combined with moderate deep-layer shear may support an isolated severe threat. Although there is some uncertainty concerning convective coverage, the forecast environment should be enough for a few marginally severe storms. ..Broyles.. 08/17/2024 Read more

MD 1929 CONCERNING SEVERE THUNDERSTORM WATCH 629... FOR FAR SOUTHEAST KS...NORTHEAST OK...NORTHERN/CENTRAL AR...FAR SOUTHEAST MO/MO BOOTHEEL
Mesoscale Discussion 1929 NWS Storm Prediction Center Norman OK 0122 AM CDT Sat Aug 17 2024 Areas affected...Far Southeast KS...Northeast OK...Northern/Central AR...Far Southeast MO/MO Bootheel Concerning...Severe Thunderstorm Watch 629... Valid 170622Z - 170815Z The severe weather threat for Severe Thunderstorm Watch 629 continues. SUMMARY...A few damaging gusts remain possible along the outflow pushing south across central Arkansas. Isolated hail is also possible from northeast Oklahoma into far southeast Kansas, and southeast Missouri into the Missouri Bootheel. DISCUSSION...Surface analysis reveals an extensive outflow boundary extending from northwest OK southwestward into central AR and then back northeastward into northeast AR and southeast MO. Convective cluster responsible for this outflow continues to progress southeastward across northern and central AR, with the outflow now notably ahead of the deep convection. This displacement between the deep convection and the outflow should persist, and perhaps even increase, over the next few hours with the overall intensity/organization of the convective line expected to decrease. Farther northwest, warm-air advection atop the outflow has resulted in more cellular development across northeast OK and southeast KS. Moderate elevated buoyancy (i.e. MUCAPE from around 2000-2500 J/kg) and moderate vertical shear (i.e. effective bulk shear around 30 to 35 kt) is supporting strong to occasionally severe storms within this warm-air advection regime. Overall storm coverage is likely near a maximum now, with isolated hail possible for the next hour or two. Lastly, a few storms have quickly intensified across far southeast MO/MO Bootheel over the past hour, amid modest warm-air advection near the outflow. Buoyancy is less in this region than areas south and west, but bulk shear is slightly stronger. As a result, some isolated hail is possible here for the next hour or two as well. ..Mosier.. 08/17/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PAH...MEG...LSX...LZK...SGF...SHV...TSA...ICT... LAT...LON 36579611 37869621 37799525 36539366 36389229 37379067 36948942 36268968 34509192 34079313 34339426 35219525 36579611 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0152 AM CDT Sat Aug 17 2024 Valid 171200Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEASTERN OREGON... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHWESTERN NEVADA... ...Synopsis... A mid-level trough will impinge on the West Coast as upper ridging amplifies over the Rockies into the Plains today. Surface cyclone development is likely to the lee of the Cascades by afternoon, promoting ample buoyancy, lift, and shear for thunderstorms, some of which may be strong. Otherwise, strong downslope and isallobaric flow across the western Great Basin ahead of the upper trough/surface low will promote widespread dry and breezy conditions capable of supporting wildfire spread. ...Along and to the lee of the Cascades - Thunderstorms... By late afternoon, multiple strong thunderstorms should develop amid strong flow aloft. Some of the storms may be high-based, with a couple of dry strikes possible. Of greater concern is the potential for erratic and strong to possibly severe gusts, which may exacerbate ongoing fire concerns, as well as with ignitions from strikes accompanying the storms. Given receptive fuels, isolated dry thunderstorm highlights have been maintained. ...Harney Basin and western Great Basin - Dry/Windy Conditions... By afternoon peak heating, RH is expected to drop into the 15-20 percent range as the boundary layer mixes. When also considering the contribution of isallobaric flow, winds may sustain above 20 mph, particularly over portions of the Harney Basin and in southwestern Nevada, where Critical highlights have been maintained. Otherwise, Elevated highlights remain over a broader area where dry and breezy conditions are expected to overlap with dry fuel beds. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0152 AM CDT Sat Aug 17 2024 Valid 171200Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEASTERN OREGON... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHWESTERN NEVADA... ...Synopsis... A mid-level trough will impinge on the West Coast as upper ridging amplifies over the Rockies into the Plains today. Surface cyclone development is likely to the lee of the Cascades by afternoon, promoting ample buoyancy, lift, and shear for thunderstorms, some of which may be strong. Otherwise, strong downslope and isallobaric flow across the western Great Basin ahead of the upper trough/surface low will promote widespread dry and breezy conditions capable of supporting wildfire spread. ...Along and to the lee of the Cascades - Thunderstorms... By late afternoon, multiple strong thunderstorms should develop amid strong flow aloft. Some of the storms may be high-based, with a couple of dry strikes possible. Of greater concern is the potential for erratic and strong to possibly severe gusts, which may exacerbate ongoing fire concerns, as well as with ignitions from strikes accompanying the storms. Given receptive fuels, isolated dry thunderstorm highlights have been maintained. ...Harney Basin and western Great Basin - Dry/Windy Conditions... By afternoon peak heating, RH is expected to drop into the 15-20 percent range as the boundary layer mixes. When also considering the contribution of isallobaric flow, winds may sustain above 20 mph, particularly over portions of the Harney Basin and in southwestern Nevada, where Critical highlights have been maintained. Otherwise, Elevated highlights remain over a broader area where dry and breezy conditions are expected to overlap with dry fuel beds. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0152 AM CDT Sat Aug 17 2024 Valid 171200Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEASTERN OREGON... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHWESTERN NEVADA... ...Synopsis... A mid-level trough will impinge on the West Coast as upper ridging amplifies over the Rockies into the Plains today. Surface cyclone development is likely to the lee of the Cascades by afternoon, promoting ample buoyancy, lift, and shear for thunderstorms, some of which may be strong. Otherwise, strong downslope and isallobaric flow across the western Great Basin ahead of the upper trough/surface low will promote widespread dry and breezy conditions capable of supporting wildfire spread. ...Along and to the lee of the Cascades - Thunderstorms... By late afternoon, multiple strong thunderstorms should develop amid strong flow aloft. Some of the storms may be high-based, with a couple of dry strikes possible. Of greater concern is the potential for erratic and strong to possibly severe gusts, which may exacerbate ongoing fire concerns, as well as with ignitions from strikes accompanying the storms. Given receptive fuels, isolated dry thunderstorm highlights have been maintained. ...Harney Basin and western Great Basin - Dry/Windy Conditions... By afternoon peak heating, RH is expected to drop into the 15-20 percent range as the boundary layer mixes. When also considering the contribution of isallobaric flow, winds may sustain above 20 mph, particularly over portions of the Harney Basin and in southwestern Nevada, where Critical highlights have been maintained. Otherwise, Elevated highlights remain over a broader area where dry and breezy conditions are expected to overlap with dry fuel beds. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0152 AM CDT Sat Aug 17 2024 Valid 171200Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEASTERN OREGON... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHWESTERN NEVADA... ...Synopsis... A mid-level trough will impinge on the West Coast as upper ridging amplifies over the Rockies into the Plains today. Surface cyclone development is likely to the lee of the Cascades by afternoon, promoting ample buoyancy, lift, and shear for thunderstorms, some of which may be strong. Otherwise, strong downslope and isallobaric flow across the western Great Basin ahead of the upper trough/surface low will promote widespread dry and breezy conditions capable of supporting wildfire spread. ...Along and to the lee of the Cascades - Thunderstorms... By late afternoon, multiple strong thunderstorms should develop amid strong flow aloft. Some of the storms may be high-based, with a couple of dry strikes possible. Of greater concern is the potential for erratic and strong to possibly severe gusts, which may exacerbate ongoing fire concerns, as well as with ignitions from strikes accompanying the storms. Given receptive fuels, isolated dry thunderstorm highlights have been maintained. ...Harney Basin and western Great Basin - Dry/Windy Conditions... By afternoon peak heating, RH is expected to drop into the 15-20 percent range as the boundary layer mixes. When also considering the contribution of isallobaric flow, winds may sustain above 20 mph, particularly over portions of the Harney Basin and in southwestern Nevada, where Critical highlights have been maintained. Otherwise, Elevated highlights remain over a broader area where dry and breezy conditions are expected to overlap with dry fuel beds. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0152 AM CDT Sat Aug 17 2024 Valid 171200Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEASTERN OREGON... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHWESTERN NEVADA... ...Synopsis... A mid-level trough will impinge on the West Coast as upper ridging amplifies over the Rockies into the Plains today. Surface cyclone development is likely to the lee of the Cascades by afternoon, promoting ample buoyancy, lift, and shear for thunderstorms, some of which may be strong. Otherwise, strong downslope and isallobaric flow across the western Great Basin ahead of the upper trough/surface low will promote widespread dry and breezy conditions capable of supporting wildfire spread. ...Along and to the lee of the Cascades - Thunderstorms... By late afternoon, multiple strong thunderstorms should develop amid strong flow aloft. Some of the storms may be high-based, with a couple of dry strikes possible. Of greater concern is the potential for erratic and strong to possibly severe gusts, which may exacerbate ongoing fire concerns, as well as with ignitions from strikes accompanying the storms. Given receptive fuels, isolated dry thunderstorm highlights have been maintained. ...Harney Basin and western Great Basin - Dry/Windy Conditions... By afternoon peak heating, RH is expected to drop into the 15-20 percent range as the boundary layer mixes. When also considering the contribution of isallobaric flow, winds may sustain above 20 mph, particularly over portions of the Harney Basin and in southwestern Nevada, where Critical highlights have been maintained. Otherwise, Elevated highlights remain over a broader area where dry and breezy conditions are expected to overlap with dry fuel beds. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0152 AM CDT Sat Aug 17 2024 Valid 171200Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEASTERN OREGON... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHWESTERN NEVADA... ...Synopsis... A mid-level trough will impinge on the West Coast as upper ridging amplifies over the Rockies into the Plains today. Surface cyclone development is likely to the lee of the Cascades by afternoon, promoting ample buoyancy, lift, and shear for thunderstorms, some of which may be strong. Otherwise, strong downslope and isallobaric flow across the western Great Basin ahead of the upper trough/surface low will promote widespread dry and breezy conditions capable of supporting wildfire spread. ...Along and to the lee of the Cascades - Thunderstorms... By late afternoon, multiple strong thunderstorms should develop amid strong flow aloft. Some of the storms may be high-based, with a couple of dry strikes possible. Of greater concern is the potential for erratic and strong to possibly severe gusts, which may exacerbate ongoing fire concerns, as well as with ignitions from strikes accompanying the storms. Given receptive fuels, isolated dry thunderstorm highlights have been maintained. ...Harney Basin and western Great Basin - Dry/Windy Conditions... By afternoon peak heating, RH is expected to drop into the 15-20 percent range as the boundary layer mixes. When also considering the contribution of isallobaric flow, winds may sustain above 20 mph, particularly over portions of the Harney Basin and in southwestern Nevada, where Critical highlights have been maintained. Otherwise, Elevated highlights remain over a broader area where dry and breezy conditions are expected to overlap with dry fuel beds. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0152 AM CDT Sat Aug 17 2024 Valid 171200Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEASTERN OREGON... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHWESTERN NEVADA... ...Synopsis... A mid-level trough will impinge on the West Coast as upper ridging amplifies over the Rockies into the Plains today. Surface cyclone development is likely to the lee of the Cascades by afternoon, promoting ample buoyancy, lift, and shear for thunderstorms, some of which may be strong. Otherwise, strong downslope and isallobaric flow across the western Great Basin ahead of the upper trough/surface low will promote widespread dry and breezy conditions capable of supporting wildfire spread. ...Along and to the lee of the Cascades - Thunderstorms... By late afternoon, multiple strong thunderstorms should develop amid strong flow aloft. Some of the storms may be high-based, with a couple of dry strikes possible. Of greater concern is the potential for erratic and strong to possibly severe gusts, which may exacerbate ongoing fire concerns, as well as with ignitions from strikes accompanying the storms. Given receptive fuels, isolated dry thunderstorm highlights have been maintained. ...Harney Basin and western Great Basin - Dry/Windy Conditions... By afternoon peak heating, RH is expected to drop into the 15-20 percent range as the boundary layer mixes. When also considering the contribution of isallobaric flow, winds may sustain above 20 mph, particularly over portions of the Harney Basin and in southwestern Nevada, where Critical highlights have been maintained. Otherwise, Elevated highlights remain over a broader area where dry and breezy conditions are expected to overlap with dry fuel beds. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CAROLINAS AND SOUTHEAST... ...SUMMARY... Scattered strong thunderstorms, associated with a severe threat, will be possible on Sunday from the Mid-Atlantic and Carolinas westward into the Southeast, and in parts of the central and northern Plains. ...Mid-Atlantic/Carolinas/Southeast An upper-level trough will move across the Ohio Valley and southern Appalachians on Sunday. At the surface, an associated cold front will approach the Mid Atlantic Seaboard, and move into the Southeast. Ahead of the front, surface dewpoints in the lower to mid 70s F, will contribute to the development of moderate instability by midday. As surface temperatures warm, thunderstorms are expected to form in the higher terrain of the southern and central Appalachians. Additional storms appear likely to develop further to the east near the front and across the moist sector ahead of the front. Current model forecasts suggest that a pocket of moderate instability, with MLCAPE potentially above 2000 J/kg, may develop in parts of the Carolinas. Forecast soundings across eastern North Carolina around 21Z show some directional shear below 850 mb, with speed shear in the mid-levels, resulting in 0-6 km shear in the 25 to 35 knot range. In addition, lapse rates are forecast to become steep, with 0-3 km lapse rates peaking near 8 C/km in the mid afternoon. This should be favorable for an isolated severe threat. The wind profile will favor multicells with isolated wind-damage potential. ...Ozarks/Lower Mississippi Valley... Northwest mid-level flow will be in place on Sunday across the lower to mid Mississippi and Tennessee Valleys. A front is forecast to move southward across the Lower Mississippi Valley and central Gulf Coast States. To the south of the front, surface dewpoints in the lower to mid 70s F will contribute to the development of moderate to strong instability. As low-level convergence increases along and ahead of the front, thunderstorms are expected to form in the early to mid afternoon. Storms will likely expand in coverage, moving southeastward across the Lower Mississippi Valley during the late afternoon. Forecast soundings at 21Z from southern Arkansas southeastward into central Mississippi have MLCAPE reaching the 2500 to 3500 J/kg range, and show 0-6 km shear in the 30 to 35 knot range. 0-3 km lapse-rates are forecast to peak near 8 C/km during the afternoon. This will be favorable for an isolated severe threat, with isolated supercells possible. However, multicell may be the prevalent storm mode. Rotating storms will have potential for isolated large hail. Severe wind gusts will be possible with any cell that can become organized. ...Central and Northern High Plains... An upper-level ridge will be in place on Sunday from the central Rockies into the northern High Plains. An axis of instability is forecast to develop to the east of the ridge from western Kansas north-northwestward into eastern Montana. Although large-scale ascent will be weak, isolated thunderstorms may form as temperatures warm during the day. Model forecasts Sunday afternoon along and near the instability axis have surface dewpoints around 60 F, steep low to mid-level lapse rates, and relatively large surface-dewpoint temperature spreads. This would be favorable for strong outflow gusts with isolated high-based storms in areas with sufficient instability. Hail will also be possible, mainly within rotating cells that come out of higher terrain, where the steepest mid-level lapse rates are forecast. ..Broyles.. 08/17/2024 Read more