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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0157 AM CST Wed Nov 08 2023 Valid 091200Z - 101200Z ...Synopsis... Elevated to critical fire weather conditions are expected to be ongoing at the beginning of the period Thursday as Santa Ana winds are likely across Ventura and Los Angeles counties. Expect these conditions to last through the morning before potentially waning Thursday afternoon. The mid-level ridge is forecast to break down on Thursday in response to the shortwave trough moving toward the Pacific Northwest. As this occurs, high pressure in the Great Basin will weaken/move into the Plains. This should bring an end to this round of Santa Ana winds across southern California. Some windy conditions are expected Thursday in the northern Plains, but fuels are still sufficiently moist to mitigate most fire weather concerns. ..Bentley.. 11/08/2023 ...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 0157 AM CST Wed Nov 08 2023 Valid 091200Z - 101200Z ...Synopsis... Elevated to critical fire weather conditions are expected to be ongoing at the beginning of the period Thursday as Santa Ana winds are likely across Ventura and Los Angeles counties. Expect these conditions to last through the morning before potentially waning Thursday afternoon. The mid-level ridge is forecast to break down on Thursday in response to the shortwave trough moving toward the Pacific Northwest. As this occurs, high pressure in the Great Basin will weaken/move into the Plains. This should bring an end to this round of Santa Ana winds across southern California. Some windy conditions are expected Thursday in the northern Plains, but fuels are still sufficiently moist to mitigate most fire weather concerns. ..Bentley.. 11/08/2023 ...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 0157 AM CST Wed Nov 08 2023 Valid 081200Z - 091200Z ...Synopsis... As a mid-level trough moves east across the Southwest, surface high pressure is arriving in its wake. This surface high is over Oregon this morning and will settle into the Great Basin by this afternoon/evening. This will set up offshore Santa Ana winds across southern California during the day today with some assistance from surface heating and deeper mixing bringing stronger winds to the surface. Therefore, as the boundary layer cools, expect some weakening of winds. However, as high pressure reintensifies across the Great Basin amid cooling overnight temperatures, expect the gradient to intensify again Thursday morning with strong offshore flow developing, particularly in Ventura county. Some Elevated to locally critical conditions may be possible across parts of the Southwest today. However, these conditions appear somewhat transient and may not last long enough to warrant an Elevated delineation. ..Bentley.. 11/08/2023 ...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 0157 AM CST Wed Nov 08 2023 Valid 081200Z - 091200Z ...Synopsis... As a mid-level trough moves east across the Southwest, surface high pressure is arriving in its wake. This surface high is over Oregon this morning and will settle into the Great Basin by this afternoon/evening. This will set up offshore Santa Ana winds across southern California during the day today with some assistance from surface heating and deeper mixing bringing stronger winds to the surface. Therefore, as the boundary layer cools, expect some weakening of winds. However, as high pressure reintensifies across the Great Basin amid cooling overnight temperatures, expect the gradient to intensify again Thursday morning with strong offshore flow developing, particularly in Ventura county. Some Elevated to locally critical conditions may be possible across parts of the Southwest today. However, these conditions appear somewhat transient and may not last long enough to warrant an Elevated delineation. ..Bentley.. 11/08/2023 ...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 0157 AM CST Wed Nov 08 2023 Valid 081200Z - 091200Z ...Synopsis... As a mid-level trough moves east across the Southwest, surface high pressure is arriving in its wake. This surface high is over Oregon this morning and will settle into the Great Basin by this afternoon/evening. This will set up offshore Santa Ana winds across southern California during the day today with some assistance from surface heating and deeper mixing bringing stronger winds to the surface. Therefore, as the boundary layer cools, expect some weakening of winds. However, as high pressure reintensifies across the Great Basin amid cooling overnight temperatures, expect the gradient to intensify again Thursday morning with strong offshore flow developing, particularly in Ventura county. Some Elevated to locally critical conditions may be possible across parts of the Southwest today. However, these conditions appear somewhat transient and may not last long enough to warrant an Elevated delineation. ..Bentley.. 11/08/2023 ...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 0157 AM CST Wed Nov 08 2023 Valid 081200Z - 091200Z ...Synopsis... As a mid-level trough moves east across the Southwest, surface high pressure is arriving in its wake. This surface high is over Oregon this morning and will settle into the Great Basin by this afternoon/evening. This will set up offshore Santa Ana winds across southern California during the day today with some assistance from surface heating and deeper mixing bringing stronger winds to the surface. Therefore, as the boundary layer cools, expect some weakening of winds. However, as high pressure reintensifies across the Great Basin amid cooling overnight temperatures, expect the gradient to intensify again Thursday morning with strong offshore flow developing, particularly in Ventura county. Some Elevated to locally critical conditions may be possible across parts of the Southwest today. However, these conditions appear somewhat transient and may not last long enough to warrant an Elevated delineation. ..Bentley.. 11/08/2023 ...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 0157 AM CST Wed Nov 08 2023 Valid 081200Z - 091200Z ...Synopsis... As a mid-level trough moves east across the Southwest, surface high pressure is arriving in its wake. This surface high is over Oregon this morning and will settle into the Great Basin by this afternoon/evening. This will set up offshore Santa Ana winds across southern California during the day today with some assistance from surface heating and deeper mixing bringing stronger winds to the surface. Therefore, as the boundary layer cools, expect some weakening of winds. However, as high pressure reintensifies across the Great Basin amid cooling overnight temperatures, expect the gradient to intensify again Thursday morning with strong offshore flow developing, particularly in Ventura county. Some Elevated to locally critical conditions may be possible across parts of the Southwest today. However, these conditions appear somewhat transient and may not last long enough to warrant an Elevated delineation. ..Bentley.. 11/08/2023 ...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 0157 AM CST Wed Nov 08 2023 Valid 081200Z - 091200Z ...Synopsis... As a mid-level trough moves east across the Southwest, surface high pressure is arriving in its wake. This surface high is over Oregon this morning and will settle into the Great Basin by this afternoon/evening. This will set up offshore Santa Ana winds across southern California during the day today with some assistance from surface heating and deeper mixing bringing stronger winds to the surface. Therefore, as the boundary layer cools, expect some weakening of winds. However, as high pressure reintensifies across the Great Basin amid cooling overnight temperatures, expect the gradient to intensify again Thursday morning with strong offshore flow developing, particularly in Ventura county. Some Elevated to locally critical conditions may be possible across parts of the Southwest today. However, these conditions appear somewhat transient and may not last long enough to warrant an Elevated delineation. ..Bentley.. 11/08/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CST Wed Nov 08 2023 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from central/southern Arkansas and northern Louisiana into south Texas and the Texas Coastal Plain on Thursday. ...Synopsis and Discussion... A southern-stream shortwave trough is forecast to extend from the central Rockies into southern CA early Thursday morning. Northern stream will likely feature a maturing mid-latitude cyclone over northern MN/far northwest Ontario, with a lead shortwave moving from southern Ontario through southern Quebec. Surface low associated with this shortwave will likely progress northeastward across the St. Lawrence Valley, just to the southeast of its parent shortwave. Expansive cold front attendant to this low will stretch back southwestward in the TX Hill Country early Thursday, with gradual southeastward/eastward progression of this front anticipated along the full length of the front throughout the day. Some shallow convection is possible across the Upper OH Valley early Thursday morning. A lightning flash or two is possible, but its limited depth should keep overall coverage below 10%. Farther south, a low-amplitude shortwave trough will likely progress northeastward across TX as the cold front gradually shifts southward. This is expected to lead to the development of a weak low which will gradually move eastward along the front as it moves across the TX Hill Country and Coastal Plain. Despite pre-frontal dewpoints in the mid/upper 60s, warm temperatures aloft and limited heating (due to abundant cloud cover) will keep buoyancy modest. As a result, warm sector thunderstorm development is unlikely. However, mid-level moistening and lift associated with the low-amplitude shortwave will likely support isolated elevated thunderstorms behind the front from south TX into the northern LA and central/southern AR. Highest storm coverage is anticipated of the Arklatex region. Another strong shortwave trough is expected to move across the Pacific Northwest, with the primary frontal band associated with this wave reaching the coast Thursday afternoon. Despite cold temperatures aloft, limited low-level moisture and mild surface temperatures will keep buoyancy very low. As such, convection within the frontal band is expected to remain too shallow for lightning. A few flashes are possible along the WA coast with the more cellular activity behind this band as large-scale ascent persists and mid-level temperatures continue to cool. ..Mosier.. 11/08/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CST Wed Nov 08 2023 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from central/southern Arkansas and northern Louisiana into south Texas and the Texas Coastal Plain on Thursday. ...Synopsis and Discussion... A southern-stream shortwave trough is forecast to extend from the central Rockies into southern CA early Thursday morning. Northern stream will likely feature a maturing mid-latitude cyclone over northern MN/far northwest Ontario, with a lead shortwave moving from southern Ontario through southern Quebec. Surface low associated with this shortwave will likely progress northeastward across the St. Lawrence Valley, just to the southeast of its parent shortwave. Expansive cold front attendant to this low will stretch back southwestward in the TX Hill Country early Thursday, with gradual southeastward/eastward progression of this front anticipated along the full length of the front throughout the day. Some shallow convection is possible across the Upper OH Valley early Thursday morning. A lightning flash or two is possible, but its limited depth should keep overall coverage below 10%. Farther south, a low-amplitude shortwave trough will likely progress northeastward across TX as the cold front gradually shifts southward. This is expected to lead to the development of a weak low which will gradually move eastward along the front as it moves across the TX Hill Country and Coastal Plain. Despite pre-frontal dewpoints in the mid/upper 60s, warm temperatures aloft and limited heating (due to abundant cloud cover) will keep buoyancy modest. As a result, warm sector thunderstorm development is unlikely. However, mid-level moistening and lift associated with the low-amplitude shortwave will likely support isolated elevated thunderstorms behind the front from south TX into the northern LA and central/southern AR. Highest storm coverage is anticipated of the Arklatex region. Another strong shortwave trough is expected to move across the Pacific Northwest, with the primary frontal band associated with this wave reaching the coast Thursday afternoon. Despite cold temperatures aloft, limited low-level moisture and mild surface temperatures will keep buoyancy very low. As such, convection within the frontal band is expected to remain too shallow for lightning. A few flashes are possible along the WA coast with the more cellular activity behind this band as large-scale ascent persists and mid-level temperatures continue to cool. ..Mosier.. 11/08/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CST Wed Nov 08 2023 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from central/southern Arkansas and northern Louisiana into south Texas and the Texas Coastal Plain on Thursday. ...Synopsis and Discussion... A southern-stream shortwave trough is forecast to extend from the central Rockies into southern CA early Thursday morning. Northern stream will likely feature a maturing mid-latitude cyclone over northern MN/far northwest Ontario, with a lead shortwave moving from southern Ontario through southern Quebec. Surface low associated with this shortwave will likely progress northeastward across the St. Lawrence Valley, just to the southeast of its parent shortwave. Expansive cold front attendant to this low will stretch back southwestward in the TX Hill Country early Thursday, with gradual southeastward/eastward progression of this front anticipated along the full length of the front throughout the day. Some shallow convection is possible across the Upper OH Valley early Thursday morning. A lightning flash or two is possible, but its limited depth should keep overall coverage below 10%. Farther south, a low-amplitude shortwave trough will likely progress northeastward across TX as the cold front gradually shifts southward. This is expected to lead to the development of a weak low which will gradually move eastward along the front as it moves across the TX Hill Country and Coastal Plain. Despite pre-frontal dewpoints in the mid/upper 60s, warm temperatures aloft and limited heating (due to abundant cloud cover) will keep buoyancy modest. As a result, warm sector thunderstorm development is unlikely. However, mid-level moistening and lift associated with the low-amplitude shortwave will likely support isolated elevated thunderstorms behind the front from south TX into the northern LA and central/southern AR. Highest storm coverage is anticipated of the Arklatex region. Another strong shortwave trough is expected to move across the Pacific Northwest, with the primary frontal band associated with this wave reaching the coast Thursday afternoon. Despite cold temperatures aloft, limited low-level moisture and mild surface temperatures will keep buoyancy very low. As such, convection within the frontal band is expected to remain too shallow for lightning. A few flashes are possible along the WA coast with the more cellular activity behind this band as large-scale ascent persists and mid-level temperatures continue to cool. ..Mosier.. 11/08/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CST Wed Nov 08 2023 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from central/southern Arkansas and northern Louisiana into south Texas and the Texas Coastal Plain on Thursday. ...Synopsis and Discussion... A southern-stream shortwave trough is forecast to extend from the central Rockies into southern CA early Thursday morning. Northern stream will likely feature a maturing mid-latitude cyclone over northern MN/far northwest Ontario, with a lead shortwave moving from southern Ontario through southern Quebec. Surface low associated with this shortwave will likely progress northeastward across the St. Lawrence Valley, just to the southeast of its parent shortwave. Expansive cold front attendant to this low will stretch back southwestward in the TX Hill Country early Thursday, with gradual southeastward/eastward progression of this front anticipated along the full length of the front throughout the day. Some shallow convection is possible across the Upper OH Valley early Thursday morning. A lightning flash or two is possible, but its limited depth should keep overall coverage below 10%. Farther south, a low-amplitude shortwave trough will likely progress northeastward across TX as the cold front gradually shifts southward. This is expected to lead to the development of a weak low which will gradually move eastward along the front as it moves across the TX Hill Country and Coastal Plain. Despite pre-frontal dewpoints in the mid/upper 60s, warm temperatures aloft and limited heating (due to abundant cloud cover) will keep buoyancy modest. As a result, warm sector thunderstorm development is unlikely. However, mid-level moistening and lift associated with the low-amplitude shortwave will likely support isolated elevated thunderstorms behind the front from south TX into the northern LA and central/southern AR. Highest storm coverage is anticipated of the Arklatex region. Another strong shortwave trough is expected to move across the Pacific Northwest, with the primary frontal band associated with this wave reaching the coast Thursday afternoon. Despite cold temperatures aloft, limited low-level moisture and mild surface temperatures will keep buoyancy very low. As such, convection within the frontal band is expected to remain too shallow for lightning. A few flashes are possible along the WA coast with the more cellular activity behind this band as large-scale ascent persists and mid-level temperatures continue to cool. ..Mosier.. 11/08/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CST Wed Nov 08 2023 Valid 091200Z - 101200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from central/southern Arkansas and northern Louisiana into south Texas and the Texas Coastal Plain on Thursday. ...Synopsis and Discussion... A southern-stream shortwave trough is forecast to extend from the central Rockies into southern CA early Thursday morning. Northern stream will likely feature a maturing mid-latitude cyclone over northern MN/far northwest Ontario, with a lead shortwave moving from southern Ontario through southern Quebec. Surface low associated with this shortwave will likely progress northeastward across the St. Lawrence Valley, just to the southeast of its parent shortwave. Expansive cold front attendant to this low will stretch back southwestward in the TX Hill Country early Thursday, with gradual southeastward/eastward progression of this front anticipated along the full length of the front throughout the day. Some shallow convection is possible across the Upper OH Valley early Thursday morning. A lightning flash or two is possible, but its limited depth should keep overall coverage below 10%. Farther south, a low-amplitude shortwave trough will likely progress northeastward across TX as the cold front gradually shifts southward. This is expected to lead to the development of a weak low which will gradually move eastward along the front as it moves across the TX Hill Country and Coastal Plain. Despite pre-frontal dewpoints in the mid/upper 60s, warm temperatures aloft and limited heating (due to abundant cloud cover) will keep buoyancy modest. As a result, warm sector thunderstorm development is unlikely. However, mid-level moistening and lift associated with the low-amplitude shortwave will likely support isolated elevated thunderstorms behind the front from south TX into the northern LA and central/southern AR. Highest storm coverage is anticipated of the Arklatex region. Another strong shortwave trough is expected to move across the Pacific Northwest, with the primary frontal band associated with this wave reaching the coast Thursday afternoon. Despite cold temperatures aloft, limited low-level moisture and mild surface temperatures will keep buoyancy very low. As such, convection within the frontal band is expected to remain too shallow for lightning. A few flashes are possible along the WA coast with the more cellular activity behind this band as large-scale ascent persists and mid-level temperatures continue to cool. ..Mosier.. 11/08/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 PM CST Tue Nov 07 2023 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Wednesday. ...Synopsis... An upper-level trough (with several embedded shortwaves) is forecast to move eastward across the Plains into parts of the Midwest/Great Lakes through the forecast period. As this occurs, a surface cyclone will move from the east-central Great Plains toward the lower Great Lakes, and a trailing cold front will move through parts of the southern Plains, mid-MS Valley, and Midwest. Multiple rounds of elevated convection will be possible across the Great Lakes region. The first round will move eastward across lower MI during the morning and early afternoon, in association with a midlevel shortwave trough. The second round is expected to develop during the afternoon/evening to the north of the warm front across southern lower MI into the lower Great Lakes region, and just north of the trailing cold front into parts of southeast WI/northeast IL. The strongest storms may produce small hail within a favorably sheared environment, but elevated buoyancy appears too weak to support a severe-hail threat. Post-frontal showers may also develop during the late evening and overnight from northeast TX/southeast OK into AR, but with weaker large-scale ascent across this region, it remains uncertain as to whether convection will become deep enough to support lightning prior to the end of the forecast period. ..Dean.. 11/08/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 PM CST Tue Nov 07 2023 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Wednesday. ...Synopsis... An upper-level trough (with several embedded shortwaves) is forecast to move eastward across the Plains into parts of the Midwest/Great Lakes through the forecast period. As this occurs, a surface cyclone will move from the east-central Great Plains toward the lower Great Lakes, and a trailing cold front will move through parts of the southern Plains, mid-MS Valley, and Midwest. Multiple rounds of elevated convection will be possible across the Great Lakes region. The first round will move eastward across lower MI during the morning and early afternoon, in association with a midlevel shortwave trough. The second round is expected to develop during the afternoon/evening to the north of the warm front across southern lower MI into the lower Great Lakes region, and just north of the trailing cold front into parts of southeast WI/northeast IL. The strongest storms may produce small hail within a favorably sheared environment, but elevated buoyancy appears too weak to support a severe-hail threat. Post-frontal showers may also develop during the late evening and overnight from northeast TX/southeast OK into AR, but with weaker large-scale ascent across this region, it remains uncertain as to whether convection will become deep enough to support lightning prior to the end of the forecast period. ..Dean.. 11/08/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 PM CST Tue Nov 07 2023 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Wednesday. ...Synopsis... An upper-level trough (with several embedded shortwaves) is forecast to move eastward across the Plains into parts of the Midwest/Great Lakes through the forecast period. As this occurs, a surface cyclone will move from the east-central Great Plains toward the lower Great Lakes, and a trailing cold front will move through parts of the southern Plains, mid-MS Valley, and Midwest. Multiple rounds of elevated convection will be possible across the Great Lakes region. The first round will move eastward across lower MI during the morning and early afternoon, in association with a midlevel shortwave trough. The second round is expected to develop during the afternoon/evening to the north of the warm front across southern lower MI into the lower Great Lakes region, and just north of the trailing cold front into parts of southeast WI/northeast IL. The strongest storms may produce small hail within a favorably sheared environment, but elevated buoyancy appears too weak to support a severe-hail threat. Post-frontal showers may also develop during the late evening and overnight from northeast TX/southeast OK into AR, but with weaker large-scale ascent across this region, it remains uncertain as to whether convection will become deep enough to support lightning prior to the end of the forecast period. ..Dean.. 11/08/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 PM CST Tue Nov 07 2023 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Wednesday. ...Synopsis... An upper-level trough (with several embedded shortwaves) is forecast to move eastward across the Plains into parts of the Midwest/Great Lakes through the forecast period. As this occurs, a surface cyclone will move from the east-central Great Plains toward the lower Great Lakes, and a trailing cold front will move through parts of the southern Plains, mid-MS Valley, and Midwest. Multiple rounds of elevated convection will be possible across the Great Lakes region. The first round will move eastward across lower MI during the morning and early afternoon, in association with a midlevel shortwave trough. The second round is expected to develop during the afternoon/evening to the north of the warm front across southern lower MI into the lower Great Lakes region, and just north of the trailing cold front into parts of southeast WI/northeast IL. The strongest storms may produce small hail within a favorably sheared environment, but elevated buoyancy appears too weak to support a severe-hail threat. Post-frontal showers may also develop during the late evening and overnight from northeast TX/southeast OK into AR, but with weaker large-scale ascent across this region, it remains uncertain as to whether convection will become deep enough to support lightning prior to the end of the forecast period. ..Dean.. 11/08/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 PM CST Tue Nov 07 2023 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Wednesday. ...Synopsis... An upper-level trough (with several embedded shortwaves) is forecast to move eastward across the Plains into parts of the Midwest/Great Lakes through the forecast period. As this occurs, a surface cyclone will move from the east-central Great Plains toward the lower Great Lakes, and a trailing cold front will move through parts of the southern Plains, mid-MS Valley, and Midwest. Multiple rounds of elevated convection will be possible across the Great Lakes region. The first round will move eastward across lower MI during the morning and early afternoon, in association with a midlevel shortwave trough. The second round is expected to develop during the afternoon/evening to the north of the warm front across southern lower MI into the lower Great Lakes region, and just north of the trailing cold front into parts of southeast WI/northeast IL. The strongest storms may produce small hail within a favorably sheared environment, but elevated buoyancy appears too weak to support a severe-hail threat. Post-frontal showers may also develop during the late evening and overnight from northeast TX/southeast OK into AR, but with weaker large-scale ascent across this region, it remains uncertain as to whether convection will become deep enough to support lightning prior to the end of the forecast period. ..Dean.. 11/08/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 PM CST Tue Nov 07 2023 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Wednesday. ...Synopsis... An upper-level trough (with several embedded shortwaves) is forecast to move eastward across the Plains into parts of the Midwest/Great Lakes through the forecast period. As this occurs, a surface cyclone will move from the east-central Great Plains toward the lower Great Lakes, and a trailing cold front will move through parts of the southern Plains, mid-MS Valley, and Midwest. Multiple rounds of elevated convection will be possible across the Great Lakes region. The first round will move eastward across lower MI during the morning and early afternoon, in association with a midlevel shortwave trough. The second round is expected to develop during the afternoon/evening to the north of the warm front across southern lower MI into the lower Great Lakes region, and just north of the trailing cold front into parts of southeast WI/northeast IL. The strongest storms may produce small hail within a favorably sheared environment, but elevated buoyancy appears too weak to support a severe-hail threat. Post-frontal showers may also develop during the late evening and overnight from northeast TX/southeast OK into AR, but with weaker large-scale ascent across this region, it remains uncertain as to whether convection will become deep enough to support lightning prior to the end of the forecast period. ..Dean.. 11/08/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0654 PM CST Tue Nov 07 2023 Valid 080100Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected for the remainder of tonight. ...Southeast MN/eastern IA into WI/northern IL... Low-level moisture transport related to a strengthening low-level jet will support the development of modest MUCAPE (150-300 J/kg) late tonight into parts of WI/northern IL, and adjacent portions of southern MN and eastern IA. Elevated convection within the developing warm-advection regime may become capable of producing sporadic lightning flashes late this evening into the overnight hours, with the greatest relative coverage still expected across southern WI and far northern IL. Very isolated lightning flashes cannot be ruled out as far north as east-central MN and central WI, though very weak buoyancy should limit thunderstorm coverage in that area. ...Elsewhere... Diurnal convection across parts of the Sierra Nevada has produced sporadic lightning flashes through the afternoon. This convection is expected to diminish with time, though very isolated lightning flashes could persist into the early evening. Very sporadic lightning flashes have also been noted across northern UT, though with very weak buoyancy across the region (as noted on the 00Z SLC sounding), any lightning activity this evening is expected to remain quite sporadic and isolated. ..Dean.. 11/08/2023 Read more