SPC Day 1 Fire Weather Outlook

1 year 8 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Mon Dec 11 2023 Valid 111700Z - 121200Z ...NO CRITICAL AREAS... The previous forecast remains on track. Latest observations across southern CA/lower CO River Valley and the southern Plains show dry conditions, but generally weak winds. Latest ensemble guidance continues to show low potential for strong winds and elevated/critical fire weather conditions. ..Moore.. 12/11/2023 .PREV DISCUSSION... /ISSUED 1252 AM CST Mon Dec 11 2023/ ...Synopsis... A quasi-zonal upper-level pattern will develop as a strong upper-level trough exists the East Coast today. Surface high pressure will be present over a vast majority of the CONUS. Cooler temperatures and lighter winds over the driest fuels should keep fire weather concerns low. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 year 8 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Mon Dec 11 2023 Valid 111700Z - 121200Z ...NO CRITICAL AREAS... The previous forecast remains on track. Latest observations across southern CA/lower CO River Valley and the southern Plains show dry conditions, but generally weak winds. Latest ensemble guidance continues to show low potential for strong winds and elevated/critical fire weather conditions. ..Moore.. 12/11/2023 .PREV DISCUSSION... /ISSUED 1252 AM CST Mon Dec 11 2023/ ...Synopsis... A quasi-zonal upper-level pattern will develop as a strong upper-level trough exists the East Coast today. Surface high pressure will be present over a vast majority of the CONUS. Cooler temperatures and lighter winds over the driest fuels should keep fire weather concerns low. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 year 8 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Mon Dec 11 2023 Valid 111700Z - 121200Z ...NO CRITICAL AREAS... The previous forecast remains on track. Latest observations across southern CA/lower CO River Valley and the southern Plains show dry conditions, but generally weak winds. Latest ensemble guidance continues to show low potential for strong winds and elevated/critical fire weather conditions. ..Moore.. 12/11/2023 .PREV DISCUSSION... /ISSUED 1252 AM CST Mon Dec 11 2023/ ...Synopsis... A quasi-zonal upper-level pattern will develop as a strong upper-level trough exists the East Coast today. Surface high pressure will be present over a vast majority of the CONUS. Cooler temperatures and lighter winds over the driest fuels should keep fire weather concerns low. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 year 8 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Mon Dec 11 2023 Valid 111700Z - 121200Z ...NO CRITICAL AREAS... The previous forecast remains on track. Latest observations across southern CA/lower CO River Valley and the southern Plains show dry conditions, but generally weak winds. Latest ensemble guidance continues to show low potential for strong winds and elevated/critical fire weather conditions. ..Moore.. 12/11/2023 .PREV DISCUSSION... /ISSUED 1252 AM CST Mon Dec 11 2023/ ...Synopsis... A quasi-zonal upper-level pattern will develop as a strong upper-level trough exists the East Coast today. Surface high pressure will be present over a vast majority of the CONUS. Cooler temperatures and lighter winds over the driest fuels should keep fire weather concerns low. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC MD 2330

1 year 8 months ago
MD 2330 CONCERNING HEAVY SNOW FOR PORTIONS OF NEW YORK INTO NORTHERN NEW ENGLAND
Mesoscale Discussion 2330 NWS Storm Prediction Center Norman OK 0206 AM CST Mon Dec 11 2023 Areas affected...Portions of New York into northern New England Concerning...Heavy snow Valid 110806Z - 111400Z SUMMARY...Moderate to heavy snow, with rates up to around 0.75 to 1 inch per hour, should persist across parts of New York into New England this morning. DISCUSSION...A pronounced upper trough will continue to progress east-northeastward across the Mid-Atlantic and Northeast this morning. A surface low near southern New England will consolidate and deepen further over the next several hours as it develops northward into ME. A cold front has cleared most of the Mid-Atlantic Coast early this morning, with low-level cold advection occurring in its wake across parts of NY and New England. Low-level thermal profiles behind the cold front are marginal to support snow, with many surface observations reporting temperatures in the low to mid 30s. Still, pronounced ascent preceding the upper trough and strong low-level frontogenetic forcing are supporting a swath of precipitation extending from the eastern Mid-Atlantic into New England. Cooling thermal profiles aloft are aiding a transition from rain to snow behind the cold front, especially at higher elevations. A band of moderate to heavy snow, with snowfall rates up to around 0.75 to 1 inch per hour, should extend from parts of eastern NY into VT, northern NH, and western/northern ME for several hours this morning. This band is expected to shift gradually east-northeastward in tandem with the upper trough progression for the next several hours. ..Gleason.. 12/11/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CAR...GYX...BTV...ALY...BGM... LAT...LON 42497528 43307502 44767417 45057336 45067167 45367132 45417089 46757005 47466930 47446901 47186886 46566917 45606995 44577108 43937215 43347278 43287363 42727405 42037411 41947489 42497528 Read more

SPC Dec 11, 2023 1300 UTC Day 1 Convective Outlook

1 year 8 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0629 AM CST Mon Dec 11 2023 Valid 111300Z - 121200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected in the U.S. through tonight. ...Synopsis/Discussion... In mid/upper levels, cyclonic flow will remain over the East, but will lose amplitude in response to two processes: 1. The eastward ejection of a substantial trough now over the Lower Great Lakes and Mid-Atlantic region. The associated low-level cold front is in the process of clearing the New England Coast, with the surface-based buoyancy well south of the area, and another couple hours of 100-300 J/kg MUCAPE largely confined to between the top of a stable boundary layer and the -20 deg C thermal level. While a rogue flash cannot be ruled out around Cape Cod, lightning potential appears too low and isolated to introduce a general-thunder area. 2. Amplification and slow eastward shift of initially weak troughing now over the Pacific Coast vicinity, reaching interior OR/western ID, northwestern NV, and east-central/southwestern CA by the end of the period. Associated strengthening DCVA/cooling aloft should remain too displaced from enough elevated moisture to support a thunderstorm area until day 2. ..Edwards/Gleason.. 12/11/2023 Read more

SPC Dec 11, 2023 1300 UTC Day 1 Convective Outlook

1 year 8 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0629 AM CST Mon Dec 11 2023 Valid 111300Z - 121200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected in the U.S. through tonight. ...Synopsis/Discussion... In mid/upper levels, cyclonic flow will remain over the East, but will lose amplitude in response to two processes: 1. The eastward ejection of a substantial trough now over the Lower Great Lakes and Mid-Atlantic region. The associated low-level cold front is in the process of clearing the New England Coast, with the surface-based buoyancy well south of the area, and another couple hours of 100-300 J/kg MUCAPE largely confined to between the top of a stable boundary layer and the -20 deg C thermal level. While a rogue flash cannot be ruled out around Cape Cod, lightning potential appears too low and isolated to introduce a general-thunder area. 2. Amplification and slow eastward shift of initially weak troughing now over the Pacific Coast vicinity, reaching interior OR/western ID, northwestern NV, and east-central/southwestern CA by the end of the period. Associated strengthening DCVA/cooling aloft should remain too displaced from enough elevated moisture to support a thunderstorm area until day 2. ..Edwards/Gleason.. 12/11/2023 Read more

SPC Dec 11, 2023 1300 UTC Day 1 Convective Outlook

1 year 8 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0629 AM CST Mon Dec 11 2023 Valid 111300Z - 121200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected in the U.S. through tonight. ...Synopsis/Discussion... In mid/upper levels, cyclonic flow will remain over the East, but will lose amplitude in response to two processes: 1. The eastward ejection of a substantial trough now over the Lower Great Lakes and Mid-Atlantic region. The associated low-level cold front is in the process of clearing the New England Coast, with the surface-based buoyancy well south of the area, and another couple hours of 100-300 J/kg MUCAPE largely confined to between the top of a stable boundary layer and the -20 deg C thermal level. While a rogue flash cannot be ruled out around Cape Cod, lightning potential appears too low and isolated to introduce a general-thunder area. 2. Amplification and slow eastward shift of initially weak troughing now over the Pacific Coast vicinity, reaching interior OR/western ID, northwestern NV, and east-central/southwestern CA by the end of the period. Associated strengthening DCVA/cooling aloft should remain too displaced from enough elevated moisture to support a thunderstorm area until day 2. ..Edwards/Gleason.. 12/11/2023 Read more

SPC Dec 11, 2023 1300 UTC Day 1 Convective Outlook

1 year 8 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0629 AM CST Mon Dec 11 2023 Valid 111300Z - 121200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected in the U.S. through tonight. ...Synopsis/Discussion... In mid/upper levels, cyclonic flow will remain over the East, but will lose amplitude in response to two processes: 1. The eastward ejection of a substantial trough now over the Lower Great Lakes and Mid-Atlantic region. The associated low-level cold front is in the process of clearing the New England Coast, with the surface-based buoyancy well south of the area, and another couple hours of 100-300 J/kg MUCAPE largely confined to between the top of a stable boundary layer and the -20 deg C thermal level. While a rogue flash cannot be ruled out around Cape Cod, lightning potential appears too low and isolated to introduce a general-thunder area. 2. Amplification and slow eastward shift of initially weak troughing now over the Pacific Coast vicinity, reaching interior OR/western ID, northwestern NV, and east-central/southwestern CA by the end of the period. Associated strengthening DCVA/cooling aloft should remain too displaced from enough elevated moisture to support a thunderstorm area until day 2. ..Edwards/Gleason.. 12/11/2023 Read more

SPC Dec 11, 2023 1300 UTC Day 1 Convective Outlook

1 year 8 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0629 AM CST Mon Dec 11 2023 Valid 111300Z - 121200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected in the U.S. through tonight. ...Synopsis/Discussion... In mid/upper levels, cyclonic flow will remain over the East, but will lose amplitude in response to two processes: 1. The eastward ejection of a substantial trough now over the Lower Great Lakes and Mid-Atlantic region. The associated low-level cold front is in the process of clearing the New England Coast, with the surface-based buoyancy well south of the area, and another couple hours of 100-300 J/kg MUCAPE largely confined to between the top of a stable boundary layer and the -20 deg C thermal level. While a rogue flash cannot be ruled out around Cape Cod, lightning potential appears too low and isolated to introduce a general-thunder area. 2. Amplification and slow eastward shift of initially weak troughing now over the Pacific Coast vicinity, reaching interior OR/western ID, northwestern NV, and east-central/southwestern CA by the end of the period. Associated strengthening DCVA/cooling aloft should remain too displaced from enough elevated moisture to support a thunderstorm area until day 2. ..Edwards/Gleason.. 12/11/2023 Read more

SPC Dec 11, 2023 1300 UTC Day 1 Convective Outlook

1 year 8 months ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0629 AM CST Mon Dec 11 2023 Valid 111300Z - 121200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected in the U.S. through tonight. ...Synopsis/Discussion... In mid/upper levels, cyclonic flow will remain over the East, but will lose amplitude in response to two processes: 1. The eastward ejection of a substantial trough now over the Lower Great Lakes and Mid-Atlantic region. The associated low-level cold front is in the process of clearing the New England Coast, with the surface-based buoyancy well south of the area, and another couple hours of 100-300 J/kg MUCAPE largely confined to between the top of a stable boundary layer and the -20 deg C thermal level. While a rogue flash cannot be ruled out around Cape Cod, lightning potential appears too low and isolated to introduce a general-thunder area. 2. Amplification and slow eastward shift of initially weak troughing now over the Pacific Coast vicinity, reaching interior OR/western ID, northwestern NV, and east-central/southwestern CA by the end of the period. Associated strengthening DCVA/cooling aloft should remain too displaced from enough elevated moisture to support a thunderstorm area until day 2. ..Edwards/Gleason.. 12/11/2023 Read more

SPC Dec 11, 2023 Day 4-8 Severe Weather Outlook

1 year 8 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0335 AM CST Mon Dec 11 2023 Valid 141200Z - 191200Z ...DISCUSSION... Severe probabilities appear negligible through D5. An area-of-interest for increasing severe potential during D6-8 continues across the eastern Gulf to south Atlantic Coasts. An initially stout surface anticyclone will weaken heading into the weekend over the OH Valley to central Appalachians. A remnant continental polar airmass will largely remain entrenched across the Southeast outside of the FL Peninsula. Deterministic 00Z guidance has trended towards increasing agreement with slow eastward progression of an upper low over the Southwest across the southern Great Plains into the Gulf this weekend. This will likely support cyclogenesis over the predominately offshore (outside of the FL Peninsula) baroclinic zone, which ECMWF ensemble and GEFS members have increasingly trended towards supporting their parent deterministic runs. But the degree of cyclone amplification remains quite varied, which has related impacts on timing/location of a potentially favorable warm-sector environment. This renders low predictability for a 15 percent severe weather area. Read more

SPC Dec 11, 2023 Day 4-8 Severe Weather Outlook

1 year 8 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0335 AM CST Mon Dec 11 2023 Valid 141200Z - 191200Z ...DISCUSSION... Severe probabilities appear negligible through D5. An area-of-interest for increasing severe potential during D6-8 continues across the eastern Gulf to south Atlantic Coasts. An initially stout surface anticyclone will weaken heading into the weekend over the OH Valley to central Appalachians. A remnant continental polar airmass will largely remain entrenched across the Southeast outside of the FL Peninsula. Deterministic 00Z guidance has trended towards increasing agreement with slow eastward progression of an upper low over the Southwest across the southern Great Plains into the Gulf this weekend. This will likely support cyclogenesis over the predominately offshore (outside of the FL Peninsula) baroclinic zone, which ECMWF ensemble and GEFS members have increasingly trended towards supporting their parent deterministic runs. But the degree of cyclone amplification remains quite varied, which has related impacts on timing/location of a potentially favorable warm-sector environment. This renders low predictability for a 15 percent severe weather area. Read more

SPC Dec 11, 2023 Day 4-8 Severe Weather Outlook

1 year 8 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0335 AM CST Mon Dec 11 2023 Valid 141200Z - 191200Z ...DISCUSSION... Severe probabilities appear negligible through D5. An area-of-interest for increasing severe potential during D6-8 continues across the eastern Gulf to south Atlantic Coasts. An initially stout surface anticyclone will weaken heading into the weekend over the OH Valley to central Appalachians. A remnant continental polar airmass will largely remain entrenched across the Southeast outside of the FL Peninsula. Deterministic 00Z guidance has trended towards increasing agreement with slow eastward progression of an upper low over the Southwest across the southern Great Plains into the Gulf this weekend. This will likely support cyclogenesis over the predominately offshore (outside of the FL Peninsula) baroclinic zone, which ECMWF ensemble and GEFS members have increasingly trended towards supporting their parent deterministic runs. But the degree of cyclone amplification remains quite varied, which has related impacts on timing/location of a potentially favorable warm-sector environment. This renders low predictability for a 15 percent severe weather area. Read more

SPC Dec 11, 2023 Day 4-8 Severe Weather Outlook

1 year 8 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0335 AM CST Mon Dec 11 2023 Valid 141200Z - 191200Z ...DISCUSSION... Severe probabilities appear negligible through D5. An area-of-interest for increasing severe potential during D6-8 continues across the eastern Gulf to south Atlantic Coasts. An initially stout surface anticyclone will weaken heading into the weekend over the OH Valley to central Appalachians. A remnant continental polar airmass will largely remain entrenched across the Southeast outside of the FL Peninsula. Deterministic 00Z guidance has trended towards increasing agreement with slow eastward progression of an upper low over the Southwest across the southern Great Plains into the Gulf this weekend. This will likely support cyclogenesis over the predominately offshore (outside of the FL Peninsula) baroclinic zone, which ECMWF ensemble and GEFS members have increasingly trended towards supporting their parent deterministic runs. But the degree of cyclone amplification remains quite varied, which has related impacts on timing/location of a potentially favorable warm-sector environment. This renders low predictability for a 15 percent severe weather area. Read more

SPC Dec 11, 2023 Day 4-8 Severe Weather Outlook

1 year 8 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0335 AM CST Mon Dec 11 2023 Valid 141200Z - 191200Z ...DISCUSSION... Severe probabilities appear negligible through D5. An area-of-interest for increasing severe potential during D6-8 continues across the eastern Gulf to south Atlantic Coasts. An initially stout surface anticyclone will weaken heading into the weekend over the OH Valley to central Appalachians. A remnant continental polar airmass will largely remain entrenched across the Southeast outside of the FL Peninsula. Deterministic 00Z guidance has trended towards increasing agreement with slow eastward progression of an upper low over the Southwest across the southern Great Plains into the Gulf this weekend. This will likely support cyclogenesis over the predominately offshore (outside of the FL Peninsula) baroclinic zone, which ECMWF ensemble and GEFS members have increasingly trended towards supporting their parent deterministic runs. But the degree of cyclone amplification remains quite varied, which has related impacts on timing/location of a potentially favorable warm-sector environment. This renders low predictability for a 15 percent severe weather area. Read more

SPC Dec 11, 2023 Day 4-8 Severe Weather Outlook

1 year 8 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0335 AM CST Mon Dec 11 2023 Valid 141200Z - 191200Z ...DISCUSSION... Severe probabilities appear negligible through D5. An area-of-interest for increasing severe potential during D6-8 continues across the eastern Gulf to south Atlantic Coasts. An initially stout surface anticyclone will weaken heading into the weekend over the OH Valley to central Appalachians. A remnant continental polar airmass will largely remain entrenched across the Southeast outside of the FL Peninsula. Deterministic 00Z guidance has trended towards increasing agreement with slow eastward progression of an upper low over the Southwest across the southern Great Plains into the Gulf this weekend. This will likely support cyclogenesis over the predominately offshore (outside of the FL Peninsula) baroclinic zone, which ECMWF ensemble and GEFS members have increasingly trended towards supporting their parent deterministic runs. But the degree of cyclone amplification remains quite varied, which has related impacts on timing/location of a potentially favorable warm-sector environment. This renders low predictability for a 15 percent severe weather area. Read more

SPC Dec 11, 2023 Day 4-8 Severe Weather Outlook

1 year 8 months ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0335 AM CST Mon Dec 11 2023 Valid 141200Z - 191200Z ...DISCUSSION... Severe probabilities appear negligible through D5. An area-of-interest for increasing severe potential during D6-8 continues across the eastern Gulf to south Atlantic Coasts. An initially stout surface anticyclone will weaken heading into the weekend over the OH Valley to central Appalachians. A remnant continental polar airmass will largely remain entrenched across the Southeast outside of the FL Peninsula. Deterministic 00Z guidance has trended towards increasing agreement with slow eastward progression of an upper low over the Southwest across the southern Great Plains into the Gulf this weekend. This will likely support cyclogenesis over the predominately offshore (outside of the FL Peninsula) baroclinic zone, which ECMWF ensemble and GEFS members have increasingly trended towards supporting their parent deterministic runs. But the degree of cyclone amplification remains quite varied, which has related impacts on timing/location of a potentially favorable warm-sector environment. This renders low predictability for a 15 percent severe weather area. Read more

SPC Dec 11, 2023 0830 UTC Day 3 Severe Thunderstorm Outlook

1 year 8 months ago
SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0217 AM CST Mon Dec 11 2023 Valid 131200Z - 141200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Wednesday. ...Southwest... A mid-level low over the Lower CO Valley should pivot and drift east across AZ through the period. Scant to meager elevated buoyancy will become increasingly pervasive downstream of this low. Sporadic lightning flashes should be favored in the first half of the period within a modest but persistent low-level warm theta-e advection regime. Convective coverage should increase Wednesday evening into the night as the cold-core region of the mid-level low shifts east, with an attendant corridor of steeper lapse rates overspreading the marginal moisture plume. The bulk of strong mid-level flow should remain confined to Sonora/Chihuahua, but small hail might occur overnight across south NM. ...South FL... Above-average agreement exists across guidance with the depiction of a stout 1040+ mb anticyclone centered on IL/IN Wednesday afternoon. This will influence persistent east-northeasterly low-level flow across FL, with gradual moistening anticipated. More prominent model differences occur with the depth of this low-level moistening and the erosion of a relatively warm/dry layer centered on 700 mb. In addition, weak lapse rates centered on 400 mb, near the -20 C level, further lowers confidence in whether lower-topped convection can acquire charge separation outside of the FL Straits. Still, enough signal exists to warrant a low thunderstorm probability. ..Grams.. 12/11/2023 Read more