Severe Storms

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1247 AM CDT Sun Nov 05 2023 Valid 061200Z - 071200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from the Pacific Northwest into Idaho and far southwest Montana, as well as over Lower Michigan, on Monday. ...Synopsis and Discussion... Surface low is forecast to be over western Lake Superior early Monday morning, with a cold front extending southwestward from this low to another secondary low over central KS. The primary low is expected to progress eastward throughout the day, moving across the Upper Great Lakes and northeast Ontario into southern Quebec, just ahead of its parent shortwave trough. Portion of the front close to the low will make steady eastward progress across the Upper Great Lakes and OH Valley. Some modest buoyancy is possible across Lower MI within the warm-air advection zone ahead of the front, contributing to the potential for a few deeper updrafts and isolated lightning flashes. Southern portion of the front is expected to stall across KS and MO amid persistent low-level moisture return. Low-level convergence will be sustained along this boundary throughout much of the day, with dewpoints south of the boundary approaching 60 deg F. Even so, warm mid-level temperatures are expected to prevent deep convection and limit thunderstorm chances. Farther west, a pair of shortwave troughs are expected to impact the Pacific Northwest. The lead wave will likely move through early Monday, continuing eastward into the northern Rockies Monday evening. A second, more amplified wave will follow in the wake of the first, approaching the Pacific Northwest and northern/central CA coast early Tuesday morning. Cold mid-level temperatures amid favorable large-scale forcing for ascent will support the potential for a few deeper convective cores capable of lightning from eastern OR into southern ID during the afternoon and evening. Multiple rounds of convection are also possible along the coast as the shortwaves move through. Cold mid-level temperatures will support modest buoyancy over this region as well, with some isolated lightning possible. ..Mosier.. 11/05/2023 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1247 AM CDT Sun Nov 05 2023 Valid 061200Z - 071200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from the Pacific Northwest into Idaho and far southwest Montana, as well as over Lower Michigan, on Monday. ...Synopsis and Discussion... Surface low is forecast to be over western Lake Superior early Monday morning, with a cold front extending southwestward from this low to another secondary low over central KS. The primary low is expected to progress eastward throughout the day, moving across the Upper Great Lakes and northeast Ontario into southern Quebec, just ahead of its parent shortwave trough. Portion of the front close to the low will make steady eastward progress across the Upper Great Lakes and OH Valley. Some modest buoyancy is possible across Lower MI within the warm-air advection zone ahead of the front, contributing to the potential for a few deeper updrafts and isolated lightning flashes. Southern portion of the front is expected to stall across KS and MO amid persistent low-level moisture return. Low-level convergence will be sustained along this boundary throughout much of the day, with dewpoints south of the boundary approaching 60 deg F. Even so, warm mid-level temperatures are expected to prevent deep convection and limit thunderstorm chances. Farther west, a pair of shortwave troughs are expected to impact the Pacific Northwest. The lead wave will likely move through early Monday, continuing eastward into the northern Rockies Monday evening. A second, more amplified wave will follow in the wake of the first, approaching the Pacific Northwest and northern/central CA coast early Tuesday morning. Cold mid-level temperatures amid favorable large-scale forcing for ascent will support the potential for a few deeper convective cores capable of lightning from eastern OR into southern ID during the afternoon and evening. Multiple rounds of convection are also possible along the coast as the shortwaves move through. Cold mid-level temperatures will support modest buoyancy over this region as well, with some isolated lightning possible. ..Mosier.. 11/05/2023 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1247 AM CDT Sun Nov 05 2023 Valid 061200Z - 071200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from the Pacific Northwest into Idaho and far southwest Montana, as well as over Lower Michigan, on Monday. ...Synopsis and Discussion... Surface low is forecast to be over western Lake Superior early Monday morning, with a cold front extending southwestward from this low to another secondary low over central KS. The primary low is expected to progress eastward throughout the day, moving across the Upper Great Lakes and northeast Ontario into southern Quebec, just ahead of its parent shortwave trough. Portion of the front close to the low will make steady eastward progress across the Upper Great Lakes and OH Valley. Some modest buoyancy is possible across Lower MI within the warm-air advection zone ahead of the front, contributing to the potential for a few deeper updrafts and isolated lightning flashes. Southern portion of the front is expected to stall across KS and MO amid persistent low-level moisture return. Low-level convergence will be sustained along this boundary throughout much of the day, with dewpoints south of the boundary approaching 60 deg F. Even so, warm mid-level temperatures are expected to prevent deep convection and limit thunderstorm chances. Farther west, a pair of shortwave troughs are expected to impact the Pacific Northwest. The lead wave will likely move through early Monday, continuing eastward into the northern Rockies Monday evening. A second, more amplified wave will follow in the wake of the first, approaching the Pacific Northwest and northern/central CA coast early Tuesday morning. Cold mid-level temperatures amid favorable large-scale forcing for ascent will support the potential for a few deeper convective cores capable of lightning from eastern OR into southern ID during the afternoon and evening. Multiple rounds of convection are also possible along the coast as the shortwaves move through. Cold mid-level temperatures will support modest buoyancy over this region as well, with some isolated lightning possible. ..Mosier.. 11/05/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1241 AM CDT Sun Nov 05 2023 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Several rounds of scattered thunderstorms are expected across the Pacific Northwest this afternoon through early Monday morning. ...Synopsis... The upper-level ridge across the central CONUS will flatten through the day on Sunday. Farther west, a mid-level trough will approach the Pacific Northwest coast. At the surface, a surface low will develop across the northern Plains in response to a shortwave moving through the region. In addition, a surface low will develop off the Oregon coast and approach the Pacific Northwest coastline near the end of the period. ...Pacific Northwest Coast... Temperatures will start to cool aloft by later this afternoon off the Oregon coast. These cooling temperatures over the marine airmass will result in an increase in thunderstorm activity during the afternoon which will persist through the overnight period. Forecast soundings show marginal instability (~250 J/kg MLCAPE) and strong shear with some low-level turning. The most favorable period for rotating updrafts and potentially some enhanced low-level rotation is expected late in the period 06Z to 12Z when the surface low approaches the coast. As this occurs, cooling temperatures aloft should result in maximum instability with some backing surface winds ahead of the approaching surface low. This pattern loosely matches previous patterns which have resulted in tornadoes in the northern California/Oregon coast environment. However, at this time, forecast instability and low-level streamwise vorticity remains too limited for a marginal risk along the coast. ..Bentley.. 11/05/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1241 AM CDT Sun Nov 05 2023 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Several rounds of scattered thunderstorms are expected across the Pacific Northwest this afternoon through early Monday morning. ...Synopsis... The upper-level ridge across the central CONUS will flatten through the day on Sunday. Farther west, a mid-level trough will approach the Pacific Northwest coast. At the surface, a surface low will develop across the northern Plains in response to a shortwave moving through the region. In addition, a surface low will develop off the Oregon coast and approach the Pacific Northwest coastline near the end of the period. ...Pacific Northwest Coast... Temperatures will start to cool aloft by later this afternoon off the Oregon coast. These cooling temperatures over the marine airmass will result in an increase in thunderstorm activity during the afternoon which will persist through the overnight period. Forecast soundings show marginal instability (~250 J/kg MLCAPE) and strong shear with some low-level turning. The most favorable period for rotating updrafts and potentially some enhanced low-level rotation is expected late in the period 06Z to 12Z when the surface low approaches the coast. As this occurs, cooling temperatures aloft should result in maximum instability with some backing surface winds ahead of the approaching surface low. This pattern loosely matches previous patterns which have resulted in tornadoes in the northern California/Oregon coast environment. However, at this time, forecast instability and low-level streamwise vorticity remains too limited for a marginal risk along the coast. ..Bentley.. 11/05/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1241 AM CDT Sun Nov 05 2023 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Several rounds of scattered thunderstorms are expected across the Pacific Northwest this afternoon through early Monday morning. ...Synopsis... The upper-level ridge across the central CONUS will flatten through the day on Sunday. Farther west, a mid-level trough will approach the Pacific Northwest coast. At the surface, a surface low will develop across the northern Plains in response to a shortwave moving through the region. In addition, a surface low will develop off the Oregon coast and approach the Pacific Northwest coastline near the end of the period. ...Pacific Northwest Coast... Temperatures will start to cool aloft by later this afternoon off the Oregon coast. These cooling temperatures over the marine airmass will result in an increase in thunderstorm activity during the afternoon which will persist through the overnight period. Forecast soundings show marginal instability (~250 J/kg MLCAPE) and strong shear with some low-level turning. The most favorable period for rotating updrafts and potentially some enhanced low-level rotation is expected late in the period 06Z to 12Z when the surface low approaches the coast. As this occurs, cooling temperatures aloft should result in maximum instability with some backing surface winds ahead of the approaching surface low. This pattern loosely matches previous patterns which have resulted in tornadoes in the northern California/Oregon coast environment. However, at this time, forecast instability and low-level streamwise vorticity remains too limited for a marginal risk along the coast. ..Bentley.. 11/05/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1241 AM CDT Sun Nov 05 2023 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Several rounds of scattered thunderstorms are expected across the Pacific Northwest this afternoon through early Monday morning. ...Synopsis... The upper-level ridge across the central CONUS will flatten through the day on Sunday. Farther west, a mid-level trough will approach the Pacific Northwest coast. At the surface, a surface low will develop across the northern Plains in response to a shortwave moving through the region. In addition, a surface low will develop off the Oregon coast and approach the Pacific Northwest coastline near the end of the period. ...Pacific Northwest Coast... Temperatures will start to cool aloft by later this afternoon off the Oregon coast. These cooling temperatures over the marine airmass will result in an increase in thunderstorm activity during the afternoon which will persist through the overnight period. Forecast soundings show marginal instability (~250 J/kg MLCAPE) and strong shear with some low-level turning. The most favorable period for rotating updrafts and potentially some enhanced low-level rotation is expected late in the period 06Z to 12Z when the surface low approaches the coast. As this occurs, cooling temperatures aloft should result in maximum instability with some backing surface winds ahead of the approaching surface low. This pattern loosely matches previous patterns which have resulted in tornadoes in the northern California/Oregon coast environment. However, at this time, forecast instability and low-level streamwise vorticity remains too limited for a marginal risk along the coast. ..Bentley.. 11/05/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0758 PM CDT Sat Nov 04 2023 Valid 050100Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. Cooling temperatures aloft will continue to support intermittent thunderstorm activity across the Northwest this evening with some threat continuing into the overnight hours. However, most thunderstorm activity is expected to dissipate by the early morning hours Sunday as larger scale dynamic support wanes. Elevated convection moving into southwest Missouri this evening has not produced any lightning thus far. The environment is most favorable for thunderstorm activity now, with a decreasing threat into the overnight hours, therefore, have removed the general thunderstorm outlook line from southeast Kansas and southwest Missouri. ..Bentley.. 11/05/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0758 PM CDT Sat Nov 04 2023 Valid 050100Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. Cooling temperatures aloft will continue to support intermittent thunderstorm activity across the Northwest this evening with some threat continuing into the overnight hours. However, most thunderstorm activity is expected to dissipate by the early morning hours Sunday as larger scale dynamic support wanes. Elevated convection moving into southwest Missouri this evening has not produced any lightning thus far. The environment is most favorable for thunderstorm activity now, with a decreasing threat into the overnight hours, therefore, have removed the general thunderstorm outlook line from southeast Kansas and southwest Missouri. ..Bentley.. 11/05/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0758 PM CDT Sat Nov 04 2023 Valid 050100Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. Cooling temperatures aloft will continue to support intermittent thunderstorm activity across the Northwest this evening with some threat continuing into the overnight hours. However, most thunderstorm activity is expected to dissipate by the early morning hours Sunday as larger scale dynamic support wanes. Elevated convection moving into southwest Missouri this evening has not produced any lightning thus far. The environment is most favorable for thunderstorm activity now, with a decreasing threat into the overnight hours, therefore, have removed the general thunderstorm outlook line from southeast Kansas and southwest Missouri. ..Bentley.. 11/05/2023 Read more

No watches are valid as of Sat Nov 4 22:42:01 UTC 2023.

No Mesoscale Discussions are in effect as of Sat Nov 4 22:42:01 UTC 2023.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0356 PM CDT Sat Nov 04 2023 Valid 061200Z - 121200Z ...Days 3-5/Monday-Wednesday... A belt of strong midlevel west-southwesterly flow will overspread the western CONUS, as a large-scale trough gradually develops. Across the Southwest, deep boundary-layer mixing along the southern fringes of the strong flow aloft will promote multiple days of dry/breezy conditions during the afternoon. While locally elevated fire-weather conditions are possible (especially over wind-prone areas), these conditions appear too marginal for Critical probabilities given marginally receptive fuels across the region. Farther east, the strengthening downslope flow across the southern High Plains will favor warm/dry conditions west of a lee trough/dryline each afternoon. This, coupled with a tightening pressure gradient and boundary-layer mixing into the strengthening flow aloft, will yield dry/windy conditions across the region -- especially on Day 4/Tuesday from eastern NM into the TX Panhandle. While fuels appear marginally receptive across the area, elevated to locally critical conditions will be possible. ...Southern California... An expansive surface high will develop over the Great Basin late in the forecast period. This will favor an offshore pressure gradient and dry/breezy conditions across southern CA. This area will need to be monitored for an increase in fire-weather potential. ..Weinman.. 11/04/2023 ...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 0356 PM CDT Sat Nov 04 2023 Valid 061200Z - 121200Z ...Days 3-5/Monday-Wednesday... A belt of strong midlevel west-southwesterly flow will overspread the western CONUS, as a large-scale trough gradually develops. Across the Southwest, deep boundary-layer mixing along the southern fringes of the strong flow aloft will promote multiple days of dry/breezy conditions during the afternoon. While locally elevated fire-weather conditions are possible (especially over wind-prone areas), these conditions appear too marginal for Critical probabilities given marginally receptive fuels across the region. Farther east, the strengthening downslope flow across the southern High Plains will favor warm/dry conditions west of a lee trough/dryline each afternoon. This, coupled with a tightening pressure gradient and boundary-layer mixing into the strengthening flow aloft, will yield dry/windy conditions across the region -- especially on Day 4/Tuesday from eastern NM into the TX Panhandle. While fuels appear marginally receptive across the area, elevated to locally critical conditions will be possible. ...Southern California... An expansive surface high will develop over the Great Basin late in the forecast period. This will favor an offshore pressure gradient and dry/breezy conditions across southern CA. This area will need to be monitored for an increase in fire-weather potential. ..Weinman.. 11/04/2023 ...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 0356 PM CDT Sat Nov 04 2023 Valid 061200Z - 121200Z ...Days 3-5/Monday-Wednesday... A belt of strong midlevel west-southwesterly flow will overspread the western CONUS, as a large-scale trough gradually develops. Across the Southwest, deep boundary-layer mixing along the southern fringes of the strong flow aloft will promote multiple days of dry/breezy conditions during the afternoon. While locally elevated fire-weather conditions are possible (especially over wind-prone areas), these conditions appear too marginal for Critical probabilities given marginally receptive fuels across the region. Farther east, the strengthening downslope flow across the southern High Plains will favor warm/dry conditions west of a lee trough/dryline each afternoon. This, coupled with a tightening pressure gradient and boundary-layer mixing into the strengthening flow aloft, will yield dry/windy conditions across the region -- especially on Day 4/Tuesday from eastern NM into the TX Panhandle. While fuels appear marginally receptive across the area, elevated to locally critical conditions will be possible. ...Southern California... An expansive surface high will develop over the Great Basin late in the forecast period. This will favor an offshore pressure gradient and dry/breezy conditions across southern CA. This area will need to be monitored for an increase in fire-weather potential. ..Weinman.. 11/04/2023 ...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 0356 PM CDT Sat Nov 04 2023 Valid 061200Z - 121200Z ...Days 3-5/Monday-Wednesday... A belt of strong midlevel west-southwesterly flow will overspread the western CONUS, as a large-scale trough gradually develops. Across the Southwest, deep boundary-layer mixing along the southern fringes of the strong flow aloft will promote multiple days of dry/breezy conditions during the afternoon. While locally elevated fire-weather conditions are possible (especially over wind-prone areas), these conditions appear too marginal for Critical probabilities given marginally receptive fuels across the region. Farther east, the strengthening downslope flow across the southern High Plains will favor warm/dry conditions west of a lee trough/dryline each afternoon. This, coupled with a tightening pressure gradient and boundary-layer mixing into the strengthening flow aloft, will yield dry/windy conditions across the region -- especially on Day 4/Tuesday from eastern NM into the TX Panhandle. While fuels appear marginally receptive across the area, elevated to locally critical conditions will be possible. ...Southern California... An expansive surface high will develop over the Great Basin late in the forecast period. This will favor an offshore pressure gradient and dry/breezy conditions across southern CA. This area will need to be monitored for an increase in fire-weather potential. ..Weinman.. 11/04/2023 ...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 0356 PM CDT Sat Nov 04 2023 Valid 061200Z - 121200Z ...Days 3-5/Monday-Wednesday... A belt of strong midlevel west-southwesterly flow will overspread the western CONUS, as a large-scale trough gradually develops. Across the Southwest, deep boundary-layer mixing along the southern fringes of the strong flow aloft will promote multiple days of dry/breezy conditions during the afternoon. While locally elevated fire-weather conditions are possible (especially over wind-prone areas), these conditions appear too marginal for Critical probabilities given marginally receptive fuels across the region. Farther east, the strengthening downslope flow across the southern High Plains will favor warm/dry conditions west of a lee trough/dryline each afternoon. This, coupled with a tightening pressure gradient and boundary-layer mixing into the strengthening flow aloft, will yield dry/windy conditions across the region -- especially on Day 4/Tuesday from eastern NM into the TX Panhandle. While fuels appear marginally receptive across the area, elevated to locally critical conditions will be possible. ...Southern California... An expansive surface high will develop over the Great Basin late in the forecast period. This will favor an offshore pressure gradient and dry/breezy conditions across southern CA. This area will need to be monitored for an increase in fire-weather potential. ..Weinman.. 11/04/2023 ...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 0356 PM CDT Sat Nov 04 2023 Valid 061200Z - 121200Z ...Days 3-5/Monday-Wednesday... A belt of strong midlevel west-southwesterly flow will overspread the western CONUS, as a large-scale trough gradually develops. Across the Southwest, deep boundary-layer mixing along the southern fringes of the strong flow aloft will promote multiple days of dry/breezy conditions during the afternoon. While locally elevated fire-weather conditions are possible (especially over wind-prone areas), these conditions appear too marginal for Critical probabilities given marginally receptive fuels across the region. Farther east, the strengthening downslope flow across the southern High Plains will favor warm/dry conditions west of a lee trough/dryline each afternoon. This, coupled with a tightening pressure gradient and boundary-layer mixing into the strengthening flow aloft, will yield dry/windy conditions across the region -- especially on Day 4/Tuesday from eastern NM into the TX Panhandle. While fuels appear marginally receptive across the area, elevated to locally critical conditions will be possible. ...Southern California... An expansive surface high will develop over the Great Basin late in the forecast period. This will favor an offshore pressure gradient and dry/breezy conditions across southern CA. This area will need to be monitored for an increase in fire-weather potential. ..Weinman.. 11/04/2023 ...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 0356 PM CDT Sat Nov 04 2023 Valid 061200Z - 121200Z ...Days 3-5/Monday-Wednesday... A belt of strong midlevel west-southwesterly flow will overspread the western CONUS, as a large-scale trough gradually develops. Across the Southwest, deep boundary-layer mixing along the southern fringes of the strong flow aloft will promote multiple days of dry/breezy conditions during the afternoon. While locally elevated fire-weather conditions are possible (especially over wind-prone areas), these conditions appear too marginal for Critical probabilities given marginally receptive fuels across the region. Farther east, the strengthening downslope flow across the southern High Plains will favor warm/dry conditions west of a lee trough/dryline each afternoon. This, coupled with a tightening pressure gradient and boundary-layer mixing into the strengthening flow aloft, will yield dry/windy conditions across the region -- especially on Day 4/Tuesday from eastern NM into the TX Panhandle. While fuels appear marginally receptive across the area, elevated to locally critical conditions will be possible. ...Southern California... An expansive surface high will develop over the Great Basin late in the forecast period. This will favor an offshore pressure gradient and dry/breezy conditions across southern CA. This area will need to be monitored for an increase in fire-weather potential. ..Weinman.. 11/04/2023 ...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 0241 PM CDT Sat Nov 04 2023 Valid 042000Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis... The only change with the 20z update is to remove the 10 percent general thunderstorm area across parts of northwest OR/far southwest WA. Isolated thunderstorms remain possible further south across southwest OR/northwest CA the next few hours, before diminishing by evening. ..Leitman.. 11/04/2023 .PREV DISCUSSION... /ISSUED 1114 AM CDT Sat Nov 04 2023/ ...Discussion... Sporadic lightning flashes have been focused this morning near the southwest OR coast where low-level convergence was maximized within the warm conveyor downstream of a large upper trough shifting northeast towards the BC coast. Convergence and large-scale ascent will gradually wane through the afternoon, yielding a diminishing thunder threat by evening along the coast. Farther inland, meager elevated buoyancy developing east of the Cascades within the warm conveyor may support very isolated thunderstorms across eastern OR and parts of western ID, mainly this evening into tonight. A limited spatiotemporal window will also exist for a few elevated thunderstorms amid scant buoyancy (MUCAPE near 100 J/kg) in the southeast KS/southwest MO vicinity this evening. Modest 850-700 mb warm theta-e advection beneath thermodynamic profiles barely adequate for charge separation will support this potential for a few hours. Relatively abrupt warming at and above 500 mb will occur with the passage of a mid-level shortwave trough moving southeast from the central Great Plains, curtailing the longevity of the low probability thunder threat. Read more