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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1151 PM CST Sun Feb 04 2024 Valid 051200Z - 061200Z ...NO CRITICAL AREAS... ...Synopsis... An upper ridge will build over the Plains states today between a mid-level trough ejecting into the Atlantic and a second trough impinging on the West Coast. Relatively cool temperatures with weak wind fields should characterize surface conditions across the Plains, with heavier precipitation falling along the West Coast and Gulf Coast areas, limiting significant wildfire-spread potential across much of the CONUS. ..Squitieri.. 02/05/2024 ...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 1151 PM CST Sun Feb 04 2024 Valid 051200Z - 061200Z ...NO CRITICAL AREAS... ...Synopsis... An upper ridge will build over the Plains states today between a mid-level trough ejecting into the Atlantic and a second trough impinging on the West Coast. Relatively cool temperatures with weak wind fields should characterize surface conditions across the Plains, with heavier precipitation falling along the West Coast and Gulf Coast areas, limiting significant wildfire-spread potential across much of the CONUS. ..Squitieri.. 02/05/2024 ...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 1151 PM CST Sun Feb 04 2024 Valid 051200Z - 061200Z ...NO CRITICAL AREAS... ...Synopsis... An upper ridge will build over the Plains states today between a mid-level trough ejecting into the Atlantic and a second trough impinging on the West Coast. Relatively cool temperatures with weak wind fields should characterize surface conditions across the Plains, with heavier precipitation falling along the West Coast and Gulf Coast areas, limiting significant wildfire-spread potential across much of the CONUS. ..Squitieri.. 02/05/2024 ...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 1151 PM CST Sun Feb 04 2024 Valid 051200Z - 061200Z ...NO CRITICAL AREAS... ...Synopsis... An upper ridge will build over the Plains states today between a mid-level trough ejecting into the Atlantic and a second trough impinging on the West Coast. Relatively cool temperatures with weak wind fields should characterize surface conditions across the Plains, with heavier precipitation falling along the West Coast and Gulf Coast areas, limiting significant wildfire-spread potential across much of the CONUS. ..Squitieri.. 02/05/2024 ...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 1151 PM CST Sun Feb 04 2024 Valid 051200Z - 061200Z ...NO CRITICAL AREAS... ...Synopsis... An upper ridge will build over the Plains states today between a mid-level trough ejecting into the Atlantic and a second trough impinging on the West Coast. Relatively cool temperatures with weak wind fields should characterize surface conditions across the Plains, with heavier precipitation falling along the West Coast and Gulf Coast areas, limiting significant wildfire-spread potential across much of the CONUS. ..Squitieri.. 02/05/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1121 PM CST Sun Feb 04 2024 Valid 051200Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TODAY ACROSS PARTS OF THE FLORIDA KEYS AND SOUTHEASTERN FLORIDA COASTAL AREAS... ...SUMMARY... A few strong storms may impact parts of the Florida Keys into southeastern peninsula coastal areas today, including one or two which may pose a risk for a tornado across parts of the Greater Miami area around mid day. ...Synopsis... Models indicate that the persistent, blocking mid/upper high over the Upper Midwest will become increasingly suppressed during this period. As this occurs, it appears that flow will become a bit more progressive across the southern mid-latitude and subtropical eastern Pacific into western Atlantic, though it may undergo some further amplification today through tonight. This probably will include building mid-level ridging across and east of the southern Rockies/northern Mexican Plateau vicinity, downstream of slowly eastward accelerating mid-level troughing (including progression farther inland across California). Downstream of the ridging, mid-level troughing (with at least an initially more consolidated embedded mid-level low digging into the northeastern Gulf of Mexico) is forecast to progress across Florida, the Caribbean and Bahamas through early Tuesday. It appears that this will be accompanied by significant surface cyclogenesis to the northeast of the Bahamas during the latter half of this period. ...Southern Florida... Models indicate that an initial area of low pressure may begin to take shape over the eastern Gulf of Mexico (offshore of the central/southern Florida peninsula) by 12Z this morning, before overspreading southern Florida by late afternoon. In the wake of a couple of preceding short wave perturbations on the leading edge of the cyclonic mid/upper flow, potentially cool air associated with substantive lower-tropospheric drying precedes the developing low, and probably will maintain a stabilizing influence across much of the peninsula through the day. Across parts of the Keys into southeastern peninsula coastal areas, Rapid Refresh and NAM forecast soundings do suggest that substantive boundary-layer destabilization is possible this morning into early afternoon. Beneath relatively cool mid-level temperatures, low-level moistening, including surface dew points increasing through the lower/mid 60s F, may become sufficient to contribute to CAPE up to around 1000 J/kg with daytime heating. In the presence of strong deep-layer shear, and perhaps coinciding with enlarging, clockwise-curved low-level hodographs across the Greater Miami vicinity, the environment may become conducive to supercells potentially capable of producing a tornado for at least an hour or two late this morning or early afternoon. ..Kerr/Squitieri.. 02/05/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1121 PM CST Sun Feb 04 2024 Valid 051200Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TODAY ACROSS PARTS OF THE FLORIDA KEYS AND SOUTHEASTERN FLORIDA COASTAL AREAS... ...SUMMARY... A few strong storms may impact parts of the Florida Keys into southeastern peninsula coastal areas today, including one or two which may pose a risk for a tornado across parts of the Greater Miami area around mid day. ...Synopsis... Models indicate that the persistent, blocking mid/upper high over the Upper Midwest will become increasingly suppressed during this period. As this occurs, it appears that flow will become a bit more progressive across the southern mid-latitude and subtropical eastern Pacific into western Atlantic, though it may undergo some further amplification today through tonight. This probably will include building mid-level ridging across and east of the southern Rockies/northern Mexican Plateau vicinity, downstream of slowly eastward accelerating mid-level troughing (including progression farther inland across California). Downstream of the ridging, mid-level troughing (with at least an initially more consolidated embedded mid-level low digging into the northeastern Gulf of Mexico) is forecast to progress across Florida, the Caribbean and Bahamas through early Tuesday. It appears that this will be accompanied by significant surface cyclogenesis to the northeast of the Bahamas during the latter half of this period. ...Southern Florida... Models indicate that an initial area of low pressure may begin to take shape over the eastern Gulf of Mexico (offshore of the central/southern Florida peninsula) by 12Z this morning, before overspreading southern Florida by late afternoon. In the wake of a couple of preceding short wave perturbations on the leading edge of the cyclonic mid/upper flow, potentially cool air associated with substantive lower-tropospheric drying precedes the developing low, and probably will maintain a stabilizing influence across much of the peninsula through the day. Across parts of the Keys into southeastern peninsula coastal areas, Rapid Refresh and NAM forecast soundings do suggest that substantive boundary-layer destabilization is possible this morning into early afternoon. Beneath relatively cool mid-level temperatures, low-level moistening, including surface dew points increasing through the lower/mid 60s F, may become sufficient to contribute to CAPE up to around 1000 J/kg with daytime heating. In the presence of strong deep-layer shear, and perhaps coinciding with enlarging, clockwise-curved low-level hodographs across the Greater Miami vicinity, the environment may become conducive to supercells potentially capable of producing a tornado for at least an hour or two late this morning or early afternoon. ..Kerr/Squitieri.. 02/05/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1121 PM CST Sun Feb 04 2024 Valid 051200Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TODAY ACROSS PARTS OF THE FLORIDA KEYS AND SOUTHEASTERN FLORIDA COASTAL AREAS... ...SUMMARY... A few strong storms may impact parts of the Florida Keys into southeastern peninsula coastal areas today, including one or two which may pose a risk for a tornado across parts of the Greater Miami area around mid day. ...Synopsis... Models indicate that the persistent, blocking mid/upper high over the Upper Midwest will become increasingly suppressed during this period. As this occurs, it appears that flow will become a bit more progressive across the southern mid-latitude and subtropical eastern Pacific into western Atlantic, though it may undergo some further amplification today through tonight. This probably will include building mid-level ridging across and east of the southern Rockies/northern Mexican Plateau vicinity, downstream of slowly eastward accelerating mid-level troughing (including progression farther inland across California). Downstream of the ridging, mid-level troughing (with at least an initially more consolidated embedded mid-level low digging into the northeastern Gulf of Mexico) is forecast to progress across Florida, the Caribbean and Bahamas through early Tuesday. It appears that this will be accompanied by significant surface cyclogenesis to the northeast of the Bahamas during the latter half of this period. ...Southern Florida... Models indicate that an initial area of low pressure may begin to take shape over the eastern Gulf of Mexico (offshore of the central/southern Florida peninsula) by 12Z this morning, before overspreading southern Florida by late afternoon. In the wake of a couple of preceding short wave perturbations on the leading edge of the cyclonic mid/upper flow, potentially cool air associated with substantive lower-tropospheric drying precedes the developing low, and probably will maintain a stabilizing influence across much of the peninsula through the day. Across parts of the Keys into southeastern peninsula coastal areas, Rapid Refresh and NAM forecast soundings do suggest that substantive boundary-layer destabilization is possible this morning into early afternoon. Beneath relatively cool mid-level temperatures, low-level moistening, including surface dew points increasing through the lower/mid 60s F, may become sufficient to contribute to CAPE up to around 1000 J/kg with daytime heating. In the presence of strong deep-layer shear, and perhaps coinciding with enlarging, clockwise-curved low-level hodographs across the Greater Miami vicinity, the environment may become conducive to supercells potentially capable of producing a tornado for at least an hour or two late this morning or early afternoon. ..Kerr/Squitieri.. 02/05/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1121 PM CST Sun Feb 04 2024 Valid 051200Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TODAY ACROSS PARTS OF THE FLORIDA KEYS AND SOUTHEASTERN FLORIDA COASTAL AREAS... ...SUMMARY... A few strong storms may impact parts of the Florida Keys into southeastern peninsula coastal areas today, including one or two which may pose a risk for a tornado across parts of the Greater Miami area around mid day. ...Synopsis... Models indicate that the persistent, blocking mid/upper high over the Upper Midwest will become increasingly suppressed during this period. As this occurs, it appears that flow will become a bit more progressive across the southern mid-latitude and subtropical eastern Pacific into western Atlantic, though it may undergo some further amplification today through tonight. This probably will include building mid-level ridging across and east of the southern Rockies/northern Mexican Plateau vicinity, downstream of slowly eastward accelerating mid-level troughing (including progression farther inland across California). Downstream of the ridging, mid-level troughing (with at least an initially more consolidated embedded mid-level low digging into the northeastern Gulf of Mexico) is forecast to progress across Florida, the Caribbean and Bahamas through early Tuesday. It appears that this will be accompanied by significant surface cyclogenesis to the northeast of the Bahamas during the latter half of this period. ...Southern Florida... Models indicate that an initial area of low pressure may begin to take shape over the eastern Gulf of Mexico (offshore of the central/southern Florida peninsula) by 12Z this morning, before overspreading southern Florida by late afternoon. In the wake of a couple of preceding short wave perturbations on the leading edge of the cyclonic mid/upper flow, potentially cool air associated with substantive lower-tropospheric drying precedes the developing low, and probably will maintain a stabilizing influence across much of the peninsula through the day. Across parts of the Keys into southeastern peninsula coastal areas, Rapid Refresh and NAM forecast soundings do suggest that substantive boundary-layer destabilization is possible this morning into early afternoon. Beneath relatively cool mid-level temperatures, low-level moistening, including surface dew points increasing through the lower/mid 60s F, may become sufficient to contribute to CAPE up to around 1000 J/kg with daytime heating. In the presence of strong deep-layer shear, and perhaps coinciding with enlarging, clockwise-curved low-level hodographs across the Greater Miami vicinity, the environment may become conducive to supercells potentially capable of producing a tornado for at least an hour or two late this morning or early afternoon. ..Kerr/Squitieri.. 02/05/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1121 PM CST Sun Feb 04 2024 Valid 051200Z - 061200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TODAY ACROSS PARTS OF THE FLORIDA KEYS AND SOUTHEASTERN FLORIDA COASTAL AREAS... ...SUMMARY... A few strong storms may impact parts of the Florida Keys into southeastern peninsula coastal areas today, including one or two which may pose a risk for a tornado across parts of the Greater Miami area around mid day. ...Synopsis... Models indicate that the persistent, blocking mid/upper high over the Upper Midwest will become increasingly suppressed during this period. As this occurs, it appears that flow will become a bit more progressive across the southern mid-latitude and subtropical eastern Pacific into western Atlantic, though it may undergo some further amplification today through tonight. This probably will include building mid-level ridging across and east of the southern Rockies/northern Mexican Plateau vicinity, downstream of slowly eastward accelerating mid-level troughing (including progression farther inland across California). Downstream of the ridging, mid-level troughing (with at least an initially more consolidated embedded mid-level low digging into the northeastern Gulf of Mexico) is forecast to progress across Florida, the Caribbean and Bahamas through early Tuesday. It appears that this will be accompanied by significant surface cyclogenesis to the northeast of the Bahamas during the latter half of this period. ...Southern Florida... Models indicate that an initial area of low pressure may begin to take shape over the eastern Gulf of Mexico (offshore of the central/southern Florida peninsula) by 12Z this morning, before overspreading southern Florida by late afternoon. In the wake of a couple of preceding short wave perturbations on the leading edge of the cyclonic mid/upper flow, potentially cool air associated with substantive lower-tropospheric drying precedes the developing low, and probably will maintain a stabilizing influence across much of the peninsula through the day. Across parts of the Keys into southeastern peninsula coastal areas, Rapid Refresh and NAM forecast soundings do suggest that substantive boundary-layer destabilization is possible this morning into early afternoon. Beneath relatively cool mid-level temperatures, low-level moistening, including surface dew points increasing through the lower/mid 60s F, may become sufficient to contribute to CAPE up to around 1000 J/kg with daytime heating. In the presence of strong deep-layer shear, and perhaps coinciding with enlarging, clockwise-curved low-level hodographs across the Greater Miami vicinity, the environment may become conducive to supercells potentially capable of producing a tornado for at least an hour or two late this morning or early afternoon. ..Kerr/Squitieri.. 02/05/2024 Read more

MD 0108 CONCERNING HEAVY SNOW FOR PORTIONS OF THE HIGHER TERRAIN OVER THE SIERRA IN CENTRAL CALIFORNIA
Mesoscale Discussion 0108 NWS Storm Prediction Center Norman OK 0429 PM CST Sun Feb 04 2024 Areas affected...portions of the higher terrain over the Sierra in central California Concerning...Heavy snow Valid 042229Z - 050230Z SUMMARY...Heavy snow should continue over the higher terrain of the Sierra in central California for at least the next 4-6 hours. In the next couple of hours, brief bouts of up to 3 inch/hour rates are possible. DISCUSSION...Heavy snow (2 inch/hr rates) should continue across the higher terrain of the Sierra over the next several hours as a mid-level trough and associated surface cyclone meanders along the CA coastline. 22Z mesoanalysis depicts a 500 mb jet streak overspreading CA (including the northern Sierra), with a pronounced 700 mb impulse beginning to approach the higher terrain along with stronger low-level warm-air advection. The net result should be continued deepening and moistening of the dendritic growth zone, which should also experience enhanced deep-layer ascent. The increase in ascent within the dendritic growth zone may support an increased snowfall rate of up to 3 inch/hr in the higher terrain of the Sierra, beginning now and continuing through at least 01Z. ..Squitieri.. 02/04/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...REV...HNX...STO... LAT...LON 37451885 38171994 38912047 39422069 39822061 39922033 39211983 38671945 38211890 37591871 37451885 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 PM CST Sun Feb 04 2024 Valid 050100Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS INTO EARLY EVENING ACROSS PARTS OF THE SACRAMENTO VALLEY AND LATE TONIGHT NEAR THE LOWER FLORIDA KEYS... ...SUMMARY... An isolated strong thunderstorm, posing some risk for severe weather, remains possible inland of the San Francisco Bay area into early evening. There also appears low potential for a strong to severe storm near the lower Florida Keys by around 7 AM EDT. ...01Z Update... ...Southeast... Lingering strong thunderstorm development, beneath the mid-level cold pool associated with an elongated mid-level low slowly digging across the Gulf Coast region, seems likely to generally weaken during the next couple of hours with the loss of daytime heating. In response to at least a few perturbations pivoting around the cyclonic circulation, including one forecast to dig across the northwestern into central Gulf of Mexico, models suggest that the low may begin to consolidate near or south-southeast (roughly) of the Mobile Bay vicinity overnight. Associated forcing for ascent may contribute to increasing thunderstorm development across the eastern Gulf of Mexico overnight. Some of this activity may begin to spread into southwestern Florida and the lower Keys by daybreak Monday. Based on latest NAM and Rapid Refresh forecast soundings, the stabilizing influence of potentially cool air, associated with ongoing low-level drying, seems likely to minimize the risk for severe weather. However, the Rapid Refresh does suggest rapid modification of this air mass is possible across the lower Keys around Key West between 11-12Z. ...Southern Sacramento Valley Vicinity... Based on Rapid Refresh forecast soundings and objective analysis, the environment inland of the San Francisco Bay area, near the Sacramento vicinity, might still be conducive to isolated low-topped supercell development late this afternoon. However, as the deep offshore cyclone continues its northward migration, and begins to weaken, it appears that this potential may diminish by 02-03Z. ..Kerr.. 02/05/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 PM CST Sun Feb 04 2024 Valid 050100Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS INTO EARLY EVENING ACROSS PARTS OF THE SACRAMENTO VALLEY AND LATE TONIGHT NEAR THE LOWER FLORIDA KEYS... ...SUMMARY... An isolated strong thunderstorm, posing some risk for severe weather, remains possible inland of the San Francisco Bay area into early evening. There also appears low potential for a strong to severe storm near the lower Florida Keys by around 7 AM EDT. ...01Z Update... ...Southeast... Lingering strong thunderstorm development, beneath the mid-level cold pool associated with an elongated mid-level low slowly digging across the Gulf Coast region, seems likely to generally weaken during the next couple of hours with the loss of daytime heating. In response to at least a few perturbations pivoting around the cyclonic circulation, including one forecast to dig across the northwestern into central Gulf of Mexico, models suggest that the low may begin to consolidate near or south-southeast (roughly) of the Mobile Bay vicinity overnight. Associated forcing for ascent may contribute to increasing thunderstorm development across the eastern Gulf of Mexico overnight. Some of this activity may begin to spread into southwestern Florida and the lower Keys by daybreak Monday. Based on latest NAM and Rapid Refresh forecast soundings, the stabilizing influence of potentially cool air, associated with ongoing low-level drying, seems likely to minimize the risk for severe weather. However, the Rapid Refresh does suggest rapid modification of this air mass is possible across the lower Keys around Key West between 11-12Z. ...Southern Sacramento Valley Vicinity... Based on Rapid Refresh forecast soundings and objective analysis, the environment inland of the San Francisco Bay area, near the Sacramento vicinity, might still be conducive to isolated low-topped supercell development late this afternoon. However, as the deep offshore cyclone continues its northward migration, and begins to weaken, it appears that this potential may diminish by 02-03Z. ..Kerr.. 02/05/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 PM CST Sun Feb 04 2024 Valid 050100Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS INTO EARLY EVENING ACROSS PARTS OF THE SACRAMENTO VALLEY AND LATE TONIGHT NEAR THE LOWER FLORIDA KEYS... ...SUMMARY... An isolated strong thunderstorm, posing some risk for severe weather, remains possible inland of the San Francisco Bay area into early evening. There also appears low potential for a strong to severe storm near the lower Florida Keys by around 7 AM EDT. ...01Z Update... ...Southeast... Lingering strong thunderstorm development, beneath the mid-level cold pool associated with an elongated mid-level low slowly digging across the Gulf Coast region, seems likely to generally weaken during the next couple of hours with the loss of daytime heating. In response to at least a few perturbations pivoting around the cyclonic circulation, including one forecast to dig across the northwestern into central Gulf of Mexico, models suggest that the low may begin to consolidate near or south-southeast (roughly) of the Mobile Bay vicinity overnight. Associated forcing for ascent may contribute to increasing thunderstorm development across the eastern Gulf of Mexico overnight. Some of this activity may begin to spread into southwestern Florida and the lower Keys by daybreak Monday. Based on latest NAM and Rapid Refresh forecast soundings, the stabilizing influence of potentially cool air, associated with ongoing low-level drying, seems likely to minimize the risk for severe weather. However, the Rapid Refresh does suggest rapid modification of this air mass is possible across the lower Keys around Key West between 11-12Z. ...Southern Sacramento Valley Vicinity... Based on Rapid Refresh forecast soundings and objective analysis, the environment inland of the San Francisco Bay area, near the Sacramento vicinity, might still be conducive to isolated low-topped supercell development late this afternoon. However, as the deep offshore cyclone continues its northward migration, and begins to weaken, it appears that this potential may diminish by 02-03Z. ..Kerr.. 02/05/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 PM CST Sun Feb 04 2024 Valid 050100Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS INTO EARLY EVENING ACROSS PARTS OF THE SACRAMENTO VALLEY AND LATE TONIGHT NEAR THE LOWER FLORIDA KEYS... ...SUMMARY... An isolated strong thunderstorm, posing some risk for severe weather, remains possible inland of the San Francisco Bay area into early evening. There also appears low potential for a strong to severe storm near the lower Florida Keys by around 7 AM EDT. ...01Z Update... ...Southeast... Lingering strong thunderstorm development, beneath the mid-level cold pool associated with an elongated mid-level low slowly digging across the Gulf Coast region, seems likely to generally weaken during the next couple of hours with the loss of daytime heating. In response to at least a few perturbations pivoting around the cyclonic circulation, including one forecast to dig across the northwestern into central Gulf of Mexico, models suggest that the low may begin to consolidate near or south-southeast (roughly) of the Mobile Bay vicinity overnight. Associated forcing for ascent may contribute to increasing thunderstorm development across the eastern Gulf of Mexico overnight. Some of this activity may begin to spread into southwestern Florida and the lower Keys by daybreak Monday. Based on latest NAM and Rapid Refresh forecast soundings, the stabilizing influence of potentially cool air, associated with ongoing low-level drying, seems likely to minimize the risk for severe weather. However, the Rapid Refresh does suggest rapid modification of this air mass is possible across the lower Keys around Key West between 11-12Z. ...Southern Sacramento Valley Vicinity... Based on Rapid Refresh forecast soundings and objective analysis, the environment inland of the San Francisco Bay area, near the Sacramento vicinity, might still be conducive to isolated low-topped supercell development late this afternoon. However, as the deep offshore cyclone continues its northward migration, and begins to weaken, it appears that this potential may diminish by 02-03Z. ..Kerr.. 02/05/2024 Read more

No watches are valid as of Sun Feb 4 23:46:02 UTC 2024.

MD 0108 CONCERNING HEAVY SNOW FOR PORTIONS OF THE HIGHER TERRAIN OVER THE SIERRA IN CENTRAL CALIFORNIA
Mesoscale Discussion 0108 NWS Storm Prediction Center Norman OK 0429 PM CST Sun Feb 04 2024 Areas affected...portions of the higher terrain over the Sierra in central California Concerning...Heavy snow Valid 042229Z - 050230Z SUMMARY...Heavy snow should continue over the higher terrain of the Sierra in central California for at least the next 4-6 hours. In the next couple of hours, brief bouts of up to 3 inch/hour rates are possible. DISCUSSION...Heavy snow (2 inch/hr rates) should continue across the higher terrain of the Sierra over the next several hours as a mid-level trough and associated surface cyclone meanders along the CA coastline. 22Z mesoanalysis depicts a 500 mb jet streak overspreading CA (including the northern Sierra), with a pronounced 700 mb impulse beginning to approach the higher terrain along with stronger low-level warm-air advection. The net result should be continued deepening and moistening of the dendritic growth zone, which should also experience enhanced deep-layer ascent. The increase in ascent within the dendritic growth zone may support an increased snowfall rate of up to 3 inch/hr in the higher terrain of the Sierra, beginning now and continuing through at least 01Z. ..Squitieri.. 02/04/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...REV...HNX...STO... LAT...LON 37451885 38171994 38912047 39422069 39822061 39922033 39211983 38671945 38211890 37591871 37451885 Read more

MD 0109 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF THE CALIFORNIA COASTLINE
Mesoscale Discussion 0109 NWS Storm Prediction Center Norman OK 0447 PM CST Sun Feb 04 2024 Areas affected...portions of the California coastline Concerning...Severe potential...Watch unlikely Valid 042247Z - 042345Z Probability of Watch Issuance...5 percent SUMMARY...A damaging gust or brief tornado cannot be ruled out over the next couple of hours. A WW issuance is not expected. DISCUSSION...A potent mid-level trough and associated surface cyclone continues to meander off of the CA coastline. Recently, surface-based buoyancy has begun to impinge on the CA coastline south of the Bay area, with somewhere between 250-500 J/kg SBCAPE (shown by 22z mesoanalysis) preceding an approaching confluence band with gradually deepening convective cells. The CAPE profile is thin. However, lapse rates are steep, and both RAP forecast soundings and the latest MUX VAD shows a very long but slightly curved hodograph, with nearly 300 m2/s2 SRH in 0-1 km layer alone. With 50+ kt flow just off of the surface, any downward momentum transport within the low-topped storms may support a severe gust. A brief tornado also cannot be ruled out, though the relatively unidirectional shear may temper this threat somewhat. The severe threat should begin to wane with the onset of nocturnal cooling. The severe threat should remain isolated and a WW issuance is not anticipated. ..Squitieri/Thompson.. 02/04/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MTR... LAT...LON 36962167 36582164 36572188 36902223 37562253 37752243 37782227 37782209 37412183 36962167 Read more

MD 0107 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR NORTHERN FL...SOUTHERN GA
Mesoscale Discussion 0107 NWS Storm Prediction Center Norman OK 0326 PM CST Sun Feb 04 2024 Areas affected...Northern FL...Southern GA Concerning...Severe potential...Watch possible Valid 042126Z - 042330Z Probability of Watch Issuance...40 percent SUMMARY...Potential for isolated damaging gusts and brief tornadoes will continue for the next few hours. DISCUSSION...21Z surface analysis places a triple point low near ABY in southwest GA. A warm front extends east-southeastward from this low across southern GA, while a surface trough extends southeastward through central portions of northern FL into the central FL Peninsula. The airmass downstream of the surface trough has destabilized amid filtered daytime heating and cold temperatures aloft (i.e. around -20 deg C at 500-mb). Low-topped convection is developing along the surface trough, and then moving north-northeasterly with the mean wind into more of north-central/northeast FL. Temperature profiles are suitable for surface-based storms, although the overall magnitude of the buoyancy is mitigated by relatively modest low-level moisture. General expectation is for a continuation of low-topped thunderstorms, with occasional supercells capable of damaging gusts and/or hail. Given the veering low-level wind profiles, there is also a low-probability chance for a tornado or two. Farther northwest close to the low (i.e southwest GA), stronger southeasterly low to mid-level flow result in a more northwestward storm motion, taking storms that develop into more hostile air. However, this storm motion also allows for more interaction with the warm front (and associated low-level vorticity), which appears to be contributing to brief strengthening of low-level rotation and tornadogenesis. Narrowing of the warm sector in this region should lead to diminishing severe potential over the next few hours. Until then, brief tornadoes remain possible. ..Mosier/Goss.. 02/04/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MLB...TBW...JAX...TAE... LAT...LON 30918389 31288424 31318269 30448118 29188155 29028227 30368308 30918389 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0336 PM CST Sun Feb 04 2024 Valid 061200Z - 121200Z Active mid-level flow is expected over the CONUS through much of the extended forecast period. A strong Pacific trough is forecast to emerge out of the Southwest and cross the southern Plains mid week. Thereafter, strong flow aloft should remain over parts of the southern Plains and central/eastern US through the remainder of the forecast period. Widespread cooler and wetter temperatures appear likely toward the end of next week as the active upper-level flow pattern continues. Overall, fire-weather concerns appear low, with the exception of some localized dry and breezy conditions possible over parts of West TX and southern NM. ...Southeast NM and southwest TX... As the aforementioned Pacific trough ejects eastward this week, a strong lee cyclone will develop over the central Plains. Gusty southwest winds are expected behind the low, bolstered by the increasingly strong flow aloft. Abundant moisture and precipitation are expected near the low across the southwestern and central US. However, portions of west TX and southern NM may remain somewhat drier comparatively. While models differ on the intensity of the upper trough and corresponding surface low, periodic dry and breezy conditions appear possible over parts of the TX Big Bend and NM from D4/Wed through D7/Sat. Still, forecast confidence remains too low for critical probabilities with area fuels only marginally dry and considerable discrepancy in medium range model guidance. ..Lyons.. 02/04/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more