Aggregator

MD 0039 CONCERNING HEAVY SNOW FOR PORTIONS OF THE MID-ATLANTIC AND NORTHEAST
Mesoscale Discussion 0039 NWS Storm Prediction Center Norman OK 0334 PM CST Sun Jan 19 2025 Areas affected...Portions of the Mid-Atlantic and Northeast Concerning...Heavy snow Valid 192134Z - 200100Z SUMMARY...Heavy snowfall will continue to shift northeastward this evening across portions of the Mid-Atlantic and Northeast with rates of >=1" per hour possible. DISCUSSION...The latest water vapor imagery indicates that the mid/upper-level speed max is exiting the coast. As a result, the surface low is deepening off of Delmarva and is forecast to continue strengthening offshore and move quickly to the northeast. Low-level frontogenesis will continue to support upward vertical motion and precipitation banding. Precipitation type is more uncertain near the coast where strong low-level warm air advection will act to offset cooling by evaporation and melting over the next few hours. Thus, the corridor with the highest confidence of 1"+ snowfall rates over the next few hours has been highlighted. ..Jirak/Mosier.. 01/19/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GYX...BOX...OKX...ALY...PHI...BGM... LAT...LON 41857286 41487335 41127372 40807419 40527458 40357527 40617574 41167540 41777467 42177422 42537378 42897315 43077272 43187218 42867184 42477217 42307238 41857286 Read more

MD 0038 CONCERNING HEAVY SNOW FOR PORTIONS OF MID-ATLANTIC STATES
Mesoscale Discussion 0038 NWS Storm Prediction Center Norman OK 1200 PM CST Sun Jan 19 2025 Areas affected...Portions of Mid-Atlantic States Concerning...Heavy snow Valid 191800Z - 192230Z SUMMARY...Snowfall will continue to increase from southwest to northeast across portions of West Virginia, Maryland, and Pennsylvania this afternoon with rates exceeding 1" per hour. DISCUSSION...An upper-level trough and associated speed max rotating around a low near Hudson Bay are moving toward the East Coast this afternoon. In response at the surface, a low over North Carolina is forecast to deepen and shift northeastward through the afternoon. To the north to northwest of the surface low, low-level frontogenesis will promote upward vertical motion and precipitation banding. Given these favorable factors and cold vertical profiles, snowfall rates of >=1" per hour are likely this afternoon with higher rates possible in banded structures. ..Jirak/Mosier.. 01/19/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PHI...CTP...LWX...RNK...PBZ...RLX... LAT...LON 39687582 39517657 39347767 39067877 38717917 38377961 38078019 38018068 38168091 38788077 39448031 40117977 40437925 40867841 40947721 40887643 40637544 40257509 39927529 39687582 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0355 PM CST Sun Jan 19 2025 Valid 211200Z - 271200Z ...Southern California - Day 3/Tuesday... Critical to extremely critical fire-weather conditions will be ongoing across southern CA at the start of the Day 3/Tuesday period, as the offshore pressure gradient will be at peak magnitudes (LAX-DAG gradient around -8 to -10 mb). This gradient, coupled with continued upper-level support through at least 15Z, will result in very strong/gusty northeasterly surface winds and single-digit RH across much of southern CA. The strongest winds should remain focused over the wind-prone Santa Ana corridor of northern/western Los Angeles County into eastern Ventura County -- where the greatest risk of Extremely Critical conditions will persist through at least 15Z. Thereafter, the positive-tilt shortwave trough and strong winds aloft that were providing upper-level support for the strong Santa Ana event on Day 3/Tuesday will continue east-southeastward into the central CONUS. However, strong surface high pressure will persist across the Intermountain West, favoring continued dry offshore flow across southern CA on Day 4/Wednesday through Day 5/Thursday. Current indications are that the offshore pressure gradient will yield elevated to locally critical fire-weather conditions both days/mornings, though the lack of upper-level support limits confidence in any more than locally critical conditions -- precluding 70-percent probabilities at this time. ..Weinman.. 01/19/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0355 PM CST Sun Jan 19 2025 Valid 211200Z - 271200Z ...Southern California - Day 3/Tuesday... Critical to extremely critical fire-weather conditions will be ongoing across southern CA at the start of the Day 3/Tuesday period, as the offshore pressure gradient will be at peak magnitudes (LAX-DAG gradient around -8 to -10 mb). This gradient, coupled with continued upper-level support through at least 15Z, will result in very strong/gusty northeasterly surface winds and single-digit RH across much of southern CA. The strongest winds should remain focused over the wind-prone Santa Ana corridor of northern/western Los Angeles County into eastern Ventura County -- where the greatest risk of Extremely Critical conditions will persist through at least 15Z. Thereafter, the positive-tilt shortwave trough and strong winds aloft that were providing upper-level support for the strong Santa Ana event on Day 3/Tuesday will continue east-southeastward into the central CONUS. However, strong surface high pressure will persist across the Intermountain West, favoring continued dry offshore flow across southern CA on Day 4/Wednesday through Day 5/Thursday. Current indications are that the offshore pressure gradient will yield elevated to locally critical fire-weather conditions both days/mornings, though the lack of upper-level support limits confidence in any more than locally critical conditions -- precluding 70-percent probabilities at this time. ..Weinman.. 01/19/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0355 PM CST Sun Jan 19 2025 Valid 211200Z - 271200Z ...Southern California - Day 3/Tuesday... Critical to extremely critical fire-weather conditions will be ongoing across southern CA at the start of the Day 3/Tuesday period, as the offshore pressure gradient will be at peak magnitudes (LAX-DAG gradient around -8 to -10 mb). This gradient, coupled with continued upper-level support through at least 15Z, will result in very strong/gusty northeasterly surface winds and single-digit RH across much of southern CA. The strongest winds should remain focused over the wind-prone Santa Ana corridor of northern/western Los Angeles County into eastern Ventura County -- where the greatest risk of Extremely Critical conditions will persist through at least 15Z. Thereafter, the positive-tilt shortwave trough and strong winds aloft that were providing upper-level support for the strong Santa Ana event on Day 3/Tuesday will continue east-southeastward into the central CONUS. However, strong surface high pressure will persist across the Intermountain West, favoring continued dry offshore flow across southern CA on Day 4/Wednesday through Day 5/Thursday. Current indications are that the offshore pressure gradient will yield elevated to locally critical fire-weather conditions both days/mornings, though the lack of upper-level support limits confidence in any more than locally critical conditions -- precluding 70-percent probabilities at this time. ..Weinman.. 01/19/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0355 PM CST Sun Jan 19 2025 Valid 211200Z - 271200Z ...Southern California - Day 3/Tuesday... Critical to extremely critical fire-weather conditions will be ongoing across southern CA at the start of the Day 3/Tuesday period, as the offshore pressure gradient will be at peak magnitudes (LAX-DAG gradient around -8 to -10 mb). This gradient, coupled with continued upper-level support through at least 15Z, will result in very strong/gusty northeasterly surface winds and single-digit RH across much of southern CA. The strongest winds should remain focused over the wind-prone Santa Ana corridor of northern/western Los Angeles County into eastern Ventura County -- where the greatest risk of Extremely Critical conditions will persist through at least 15Z. Thereafter, the positive-tilt shortwave trough and strong winds aloft that were providing upper-level support for the strong Santa Ana event on Day 3/Tuesday will continue east-southeastward into the central CONUS. However, strong surface high pressure will persist across the Intermountain West, favoring continued dry offshore flow across southern CA on Day 4/Wednesday through Day 5/Thursday. Current indications are that the offshore pressure gradient will yield elevated to locally critical fire-weather conditions both days/mornings, though the lack of upper-level support limits confidence in any more than locally critical conditions -- precluding 70-percent probabilities at this time. ..Weinman.. 01/19/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0355 PM CST Sun Jan 19 2025 Valid 211200Z - 271200Z ...Southern California - Day 3/Tuesday... Critical to extremely critical fire-weather conditions will be ongoing across southern CA at the start of the Day 3/Tuesday period, as the offshore pressure gradient will be at peak magnitudes (LAX-DAG gradient around -8 to -10 mb). This gradient, coupled with continued upper-level support through at least 15Z, will result in very strong/gusty northeasterly surface winds and single-digit RH across much of southern CA. The strongest winds should remain focused over the wind-prone Santa Ana corridor of northern/western Los Angeles County into eastern Ventura County -- where the greatest risk of Extremely Critical conditions will persist through at least 15Z. Thereafter, the positive-tilt shortwave trough and strong winds aloft that were providing upper-level support for the strong Santa Ana event on Day 3/Tuesday will continue east-southeastward into the central CONUS. However, strong surface high pressure will persist across the Intermountain West, favoring continued dry offshore flow across southern CA on Day 4/Wednesday through Day 5/Thursday. Current indications are that the offshore pressure gradient will yield elevated to locally critical fire-weather conditions both days/mornings, though the lack of upper-level support limits confidence in any more than locally critical conditions -- precluding 70-percent probabilities at this time. ..Weinman.. 01/19/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0355 PM CST Sun Jan 19 2025 Valid 211200Z - 271200Z ...Southern California - Day 3/Tuesday... Critical to extremely critical fire-weather conditions will be ongoing across southern CA at the start of the Day 3/Tuesday period, as the offshore pressure gradient will be at peak magnitudes (LAX-DAG gradient around -8 to -10 mb). This gradient, coupled with continued upper-level support through at least 15Z, will result in very strong/gusty northeasterly surface winds and single-digit RH across much of southern CA. The strongest winds should remain focused over the wind-prone Santa Ana corridor of northern/western Los Angeles County into eastern Ventura County -- where the greatest risk of Extremely Critical conditions will persist through at least 15Z. Thereafter, the positive-tilt shortwave trough and strong winds aloft that were providing upper-level support for the strong Santa Ana event on Day 3/Tuesday will continue east-southeastward into the central CONUS. However, strong surface high pressure will persist across the Intermountain West, favoring continued dry offshore flow across southern CA on Day 4/Wednesday through Day 5/Thursday. Current indications are that the offshore pressure gradient will yield elevated to locally critical fire-weather conditions both days/mornings, though the lack of upper-level support limits confidence in any more than locally critical conditions -- precluding 70-percent probabilities at this time. ..Weinman.. 01/19/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0355 PM CST Sun Jan 19 2025 Valid 211200Z - 271200Z ...Southern California - Day 3/Tuesday... Critical to extremely critical fire-weather conditions will be ongoing across southern CA at the start of the Day 3/Tuesday period, as the offshore pressure gradient will be at peak magnitudes (LAX-DAG gradient around -8 to -10 mb). This gradient, coupled with continued upper-level support through at least 15Z, will result in very strong/gusty northeasterly surface winds and single-digit RH across much of southern CA. The strongest winds should remain focused over the wind-prone Santa Ana corridor of northern/western Los Angeles County into eastern Ventura County -- where the greatest risk of Extremely Critical conditions will persist through at least 15Z. Thereafter, the positive-tilt shortwave trough and strong winds aloft that were providing upper-level support for the strong Santa Ana event on Day 3/Tuesday will continue east-southeastward into the central CONUS. However, strong surface high pressure will persist across the Intermountain West, favoring continued dry offshore flow across southern CA on Day 4/Wednesday through Day 5/Thursday. Current indications are that the offshore pressure gradient will yield elevated to locally critical fire-weather conditions both days/mornings, though the lack of upper-level support limits confidence in any more than locally critical conditions -- precluding 70-percent probabilities at this time. ..Weinman.. 01/19/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Sun Jan 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... Strong thunderstorms may impact parts of central Florida this afternoon into early evening, and pose at least some risk for a tornado and locally damaging wind gusts. ...20z Update... The previous forecast remains on track as a line of thunderstorms continues to migrate south/southeast across the FL Peninsula. The 30-40 mph eastward motion of individual convective elements within the line is limiting residence time within the warmer/more buoyant air mass over land and favoring maximum convective intensity along Florida's east coast. Several severe wind gusts and a few 1-inch hail stones have been reported in the past couple of hours, and consideration was given for introducing 5% hail risk probabilities. However, the linear organization of the convection should limit the potential for additional supercells, and a general weakening trend is anticipated through early evening as the line continues south/southeast. It remains somewhat unclear exactly when the severe wind threat will fully diminish, especially given recent KMLB VWP observations showing 40-50 knot winds within the 2-3 km layer ahead of the convective line. To account for this uncertainty, the Marginal risk was expanded slightly southward ahead of the line, but convection should be sufficiently weak later this evening as it moves into south FL to preclude risk probabilities. ..Moore.. 01/19/2025 .PREV DISCUSSION... /ISSUED 1018 AM CST Sun Jan 19 2025/ ...FL Peninsula... Expansive upper troughing covers the entirety of the CONUS this morning, with moderate southwesterly flow aloft throughout the base of this trough extending from the Southeast/Gulf of Mexico across the Mid-Atlantic States and FL. Surface analysis places a low over central NC. A cold front extends southwestward from this low through southeast GA and the FL Big Bend. Modest troughing precedes this front across central FL, with broad low-level confluence in the vicinity of this pre-frontal troughing contributing to showers and thunderstorms. Modest buoyancy persists over the region, with mesoanalysis estimating MLCAPE around 500 to 750 J/kg. Showers and thunderstorms are expected to continue throughout the day as the cold front and pre-frontal troughing both shift gradually southward. The environment will remain strongly sheared (i.e. effective bulk shear around 50-55 kt) throughout the afternoon, supporting the potential for a few more organized storms capable of damaging wind gusts and perhaps even a brief tornado or two. Wind fields will weaken with southern extent, with deep-layer vertical shear weakening as well. As such, the severe potential will likely maximize this morning into the early afternoon across the central FL Peninsula. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Sun Jan 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... Strong thunderstorms may impact parts of central Florida this afternoon into early evening, and pose at least some risk for a tornado and locally damaging wind gusts. ...20z Update... The previous forecast remains on track as a line of thunderstorms continues to migrate south/southeast across the FL Peninsula. The 30-40 mph eastward motion of individual convective elements within the line is limiting residence time within the warmer/more buoyant air mass over land and favoring maximum convective intensity along Florida's east coast. Several severe wind gusts and a few 1-inch hail stones have been reported in the past couple of hours, and consideration was given for introducing 5% hail risk probabilities. However, the linear organization of the convection should limit the potential for additional supercells, and a general weakening trend is anticipated through early evening as the line continues south/southeast. It remains somewhat unclear exactly when the severe wind threat will fully diminish, especially given recent KMLB VWP observations showing 40-50 knot winds within the 2-3 km layer ahead of the convective line. To account for this uncertainty, the Marginal risk was expanded slightly southward ahead of the line, but convection should be sufficiently weak later this evening as it moves into south FL to preclude risk probabilities. ..Moore.. 01/19/2025 .PREV DISCUSSION... /ISSUED 1018 AM CST Sun Jan 19 2025/ ...FL Peninsula... Expansive upper troughing covers the entirety of the CONUS this morning, with moderate southwesterly flow aloft throughout the base of this trough extending from the Southeast/Gulf of Mexico across the Mid-Atlantic States and FL. Surface analysis places a low over central NC. A cold front extends southwestward from this low through southeast GA and the FL Big Bend. Modest troughing precedes this front across central FL, with broad low-level confluence in the vicinity of this pre-frontal troughing contributing to showers and thunderstorms. Modest buoyancy persists over the region, with mesoanalysis estimating MLCAPE around 500 to 750 J/kg. Showers and thunderstorms are expected to continue throughout the day as the cold front and pre-frontal troughing both shift gradually southward. The environment will remain strongly sheared (i.e. effective bulk shear around 50-55 kt) throughout the afternoon, supporting the potential for a few more organized storms capable of damaging wind gusts and perhaps even a brief tornado or two. Wind fields will weaken with southern extent, with deep-layer vertical shear weakening as well. As such, the severe potential will likely maximize this morning into the early afternoon across the central FL Peninsula. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Sun Jan 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... Strong thunderstorms may impact parts of central Florida this afternoon into early evening, and pose at least some risk for a tornado and locally damaging wind gusts. ...20z Update... The previous forecast remains on track as a line of thunderstorms continues to migrate south/southeast across the FL Peninsula. The 30-40 mph eastward motion of individual convective elements within the line is limiting residence time within the warmer/more buoyant air mass over land and favoring maximum convective intensity along Florida's east coast. Several severe wind gusts and a few 1-inch hail stones have been reported in the past couple of hours, and consideration was given for introducing 5% hail risk probabilities. However, the linear organization of the convection should limit the potential for additional supercells, and a general weakening trend is anticipated through early evening as the line continues south/southeast. It remains somewhat unclear exactly when the severe wind threat will fully diminish, especially given recent KMLB VWP observations showing 40-50 knot winds within the 2-3 km layer ahead of the convective line. To account for this uncertainty, the Marginal risk was expanded slightly southward ahead of the line, but convection should be sufficiently weak later this evening as it moves into south FL to preclude risk probabilities. ..Moore.. 01/19/2025 .PREV DISCUSSION... /ISSUED 1018 AM CST Sun Jan 19 2025/ ...FL Peninsula... Expansive upper troughing covers the entirety of the CONUS this morning, with moderate southwesterly flow aloft throughout the base of this trough extending from the Southeast/Gulf of Mexico across the Mid-Atlantic States and FL. Surface analysis places a low over central NC. A cold front extends southwestward from this low through southeast GA and the FL Big Bend. Modest troughing precedes this front across central FL, with broad low-level confluence in the vicinity of this pre-frontal troughing contributing to showers and thunderstorms. Modest buoyancy persists over the region, with mesoanalysis estimating MLCAPE around 500 to 750 J/kg. Showers and thunderstorms are expected to continue throughout the day as the cold front and pre-frontal troughing both shift gradually southward. The environment will remain strongly sheared (i.e. effective bulk shear around 50-55 kt) throughout the afternoon, supporting the potential for a few more organized storms capable of damaging wind gusts and perhaps even a brief tornado or two. Wind fields will weaken with southern extent, with deep-layer vertical shear weakening as well. As such, the severe potential will likely maximize this morning into the early afternoon across the central FL Peninsula. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Sun Jan 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... Strong thunderstorms may impact parts of central Florida this afternoon into early evening, and pose at least some risk for a tornado and locally damaging wind gusts. ...20z Update... The previous forecast remains on track as a line of thunderstorms continues to migrate south/southeast across the FL Peninsula. The 30-40 mph eastward motion of individual convective elements within the line is limiting residence time within the warmer/more buoyant air mass over land and favoring maximum convective intensity along Florida's east coast. Several severe wind gusts and a few 1-inch hail stones have been reported in the past couple of hours, and consideration was given for introducing 5% hail risk probabilities. However, the linear organization of the convection should limit the potential for additional supercells, and a general weakening trend is anticipated through early evening as the line continues south/southeast. It remains somewhat unclear exactly when the severe wind threat will fully diminish, especially given recent KMLB VWP observations showing 40-50 knot winds within the 2-3 km layer ahead of the convective line. To account for this uncertainty, the Marginal risk was expanded slightly southward ahead of the line, but convection should be sufficiently weak later this evening as it moves into south FL to preclude risk probabilities. ..Moore.. 01/19/2025 .PREV DISCUSSION... /ISSUED 1018 AM CST Sun Jan 19 2025/ ...FL Peninsula... Expansive upper troughing covers the entirety of the CONUS this morning, with moderate southwesterly flow aloft throughout the base of this trough extending from the Southeast/Gulf of Mexico across the Mid-Atlantic States and FL. Surface analysis places a low over central NC. A cold front extends southwestward from this low through southeast GA and the FL Big Bend. Modest troughing precedes this front across central FL, with broad low-level confluence in the vicinity of this pre-frontal troughing contributing to showers and thunderstorms. Modest buoyancy persists over the region, with mesoanalysis estimating MLCAPE around 500 to 750 J/kg. Showers and thunderstorms are expected to continue throughout the day as the cold front and pre-frontal troughing both shift gradually southward. The environment will remain strongly sheared (i.e. effective bulk shear around 50-55 kt) throughout the afternoon, supporting the potential for a few more organized storms capable of damaging wind gusts and perhaps even a brief tornado or two. Wind fields will weaken with southern extent, with deep-layer vertical shear weakening as well. As such, the severe potential will likely maximize this morning into the early afternoon across the central FL Peninsula. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Sun Jan 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... Strong thunderstorms may impact parts of central Florida this afternoon into early evening, and pose at least some risk for a tornado and locally damaging wind gusts. ...20z Update... The previous forecast remains on track as a line of thunderstorms continues to migrate south/southeast across the FL Peninsula. The 30-40 mph eastward motion of individual convective elements within the line is limiting residence time within the warmer/more buoyant air mass over land and favoring maximum convective intensity along Florida's east coast. Several severe wind gusts and a few 1-inch hail stones have been reported in the past couple of hours, and consideration was given for introducing 5% hail risk probabilities. However, the linear organization of the convection should limit the potential for additional supercells, and a general weakening trend is anticipated through early evening as the line continues south/southeast. It remains somewhat unclear exactly when the severe wind threat will fully diminish, especially given recent KMLB VWP observations showing 40-50 knot winds within the 2-3 km layer ahead of the convective line. To account for this uncertainty, the Marginal risk was expanded slightly southward ahead of the line, but convection should be sufficiently weak later this evening as it moves into south FL to preclude risk probabilities. ..Moore.. 01/19/2025 .PREV DISCUSSION... /ISSUED 1018 AM CST Sun Jan 19 2025/ ...FL Peninsula... Expansive upper troughing covers the entirety of the CONUS this morning, with moderate southwesterly flow aloft throughout the base of this trough extending from the Southeast/Gulf of Mexico across the Mid-Atlantic States and FL. Surface analysis places a low over central NC. A cold front extends southwestward from this low through southeast GA and the FL Big Bend. Modest troughing precedes this front across central FL, with broad low-level confluence in the vicinity of this pre-frontal troughing contributing to showers and thunderstorms. Modest buoyancy persists over the region, with mesoanalysis estimating MLCAPE around 500 to 750 J/kg. Showers and thunderstorms are expected to continue throughout the day as the cold front and pre-frontal troughing both shift gradually southward. The environment will remain strongly sheared (i.e. effective bulk shear around 50-55 kt) throughout the afternoon, supporting the potential for a few more organized storms capable of damaging wind gusts and perhaps even a brief tornado or two. Wind fields will weaken with southern extent, with deep-layer vertical shear weakening as well. As such, the severe potential will likely maximize this morning into the early afternoon across the central FL Peninsula. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Sun Jan 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... Strong thunderstorms may impact parts of central Florida this afternoon into early evening, and pose at least some risk for a tornado and locally damaging wind gusts. ...20z Update... The previous forecast remains on track as a line of thunderstorms continues to migrate south/southeast across the FL Peninsula. The 30-40 mph eastward motion of individual convective elements within the line is limiting residence time within the warmer/more buoyant air mass over land and favoring maximum convective intensity along Florida's east coast. Several severe wind gusts and a few 1-inch hail stones have been reported in the past couple of hours, and consideration was given for introducing 5% hail risk probabilities. However, the linear organization of the convection should limit the potential for additional supercells, and a general weakening trend is anticipated through early evening as the line continues south/southeast. It remains somewhat unclear exactly when the severe wind threat will fully diminish, especially given recent KMLB VWP observations showing 40-50 knot winds within the 2-3 km layer ahead of the convective line. To account for this uncertainty, the Marginal risk was expanded slightly southward ahead of the line, but convection should be sufficiently weak later this evening as it moves into south FL to preclude risk probabilities. ..Moore.. 01/19/2025 .PREV DISCUSSION... /ISSUED 1018 AM CST Sun Jan 19 2025/ ...FL Peninsula... Expansive upper troughing covers the entirety of the CONUS this morning, with moderate southwesterly flow aloft throughout the base of this trough extending from the Southeast/Gulf of Mexico across the Mid-Atlantic States and FL. Surface analysis places a low over central NC. A cold front extends southwestward from this low through southeast GA and the FL Big Bend. Modest troughing precedes this front across central FL, with broad low-level confluence in the vicinity of this pre-frontal troughing contributing to showers and thunderstorms. Modest buoyancy persists over the region, with mesoanalysis estimating MLCAPE around 500 to 750 J/kg. Showers and thunderstorms are expected to continue throughout the day as the cold front and pre-frontal troughing both shift gradually southward. The environment will remain strongly sheared (i.e. effective bulk shear around 50-55 kt) throughout the afternoon, supporting the potential for a few more organized storms capable of damaging wind gusts and perhaps even a brief tornado or two. Wind fields will weaken with southern extent, with deep-layer vertical shear weakening as well. As such, the severe potential will likely maximize this morning into the early afternoon across the central FL Peninsula. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Sun Jan 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... Strong thunderstorms may impact parts of central Florida this afternoon into early evening, and pose at least some risk for a tornado and locally damaging wind gusts. ...20z Update... The previous forecast remains on track as a line of thunderstorms continues to migrate south/southeast across the FL Peninsula. The 30-40 mph eastward motion of individual convective elements within the line is limiting residence time within the warmer/more buoyant air mass over land and favoring maximum convective intensity along Florida's east coast. Several severe wind gusts and a few 1-inch hail stones have been reported in the past couple of hours, and consideration was given for introducing 5% hail risk probabilities. However, the linear organization of the convection should limit the potential for additional supercells, and a general weakening trend is anticipated through early evening as the line continues south/southeast. It remains somewhat unclear exactly when the severe wind threat will fully diminish, especially given recent KMLB VWP observations showing 40-50 knot winds within the 2-3 km layer ahead of the convective line. To account for this uncertainty, the Marginal risk was expanded slightly southward ahead of the line, but convection should be sufficiently weak later this evening as it moves into south FL to preclude risk probabilities. ..Moore.. 01/19/2025 .PREV DISCUSSION... /ISSUED 1018 AM CST Sun Jan 19 2025/ ...FL Peninsula... Expansive upper troughing covers the entirety of the CONUS this morning, with moderate southwesterly flow aloft throughout the base of this trough extending from the Southeast/Gulf of Mexico across the Mid-Atlantic States and FL. Surface analysis places a low over central NC. A cold front extends southwestward from this low through southeast GA and the FL Big Bend. Modest troughing precedes this front across central FL, with broad low-level confluence in the vicinity of this pre-frontal troughing contributing to showers and thunderstorms. Modest buoyancy persists over the region, with mesoanalysis estimating MLCAPE around 500 to 750 J/kg. Showers and thunderstorms are expected to continue throughout the day as the cold front and pre-frontal troughing both shift gradually southward. The environment will remain strongly sheared (i.e. effective bulk shear around 50-55 kt) throughout the afternoon, supporting the potential for a few more organized storms capable of damaging wind gusts and perhaps even a brief tornado or two. Wind fields will weaken with southern extent, with deep-layer vertical shear weakening as well. As such, the severe potential will likely maximize this morning into the early afternoon across the central FL Peninsula. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Sun Jan 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... Strong thunderstorms may impact parts of central Florida this afternoon into early evening, and pose at least some risk for a tornado and locally damaging wind gusts. ...20z Update... The previous forecast remains on track as a line of thunderstorms continues to migrate south/southeast across the FL Peninsula. The 30-40 mph eastward motion of individual convective elements within the line is limiting residence time within the warmer/more buoyant air mass over land and favoring maximum convective intensity along Florida's east coast. Several severe wind gusts and a few 1-inch hail stones have been reported in the past couple of hours, and consideration was given for introducing 5% hail risk probabilities. However, the linear organization of the convection should limit the potential for additional supercells, and a general weakening trend is anticipated through early evening as the line continues south/southeast. It remains somewhat unclear exactly when the severe wind threat will fully diminish, especially given recent KMLB VWP observations showing 40-50 knot winds within the 2-3 km layer ahead of the convective line. To account for this uncertainty, the Marginal risk was expanded slightly southward ahead of the line, but convection should be sufficiently weak later this evening as it moves into south FL to preclude risk probabilities. ..Moore.. 01/19/2025 .PREV DISCUSSION... /ISSUED 1018 AM CST Sun Jan 19 2025/ ...FL Peninsula... Expansive upper troughing covers the entirety of the CONUS this morning, with moderate southwesterly flow aloft throughout the base of this trough extending from the Southeast/Gulf of Mexico across the Mid-Atlantic States and FL. Surface analysis places a low over central NC. A cold front extends southwestward from this low through southeast GA and the FL Big Bend. Modest troughing precedes this front across central FL, with broad low-level confluence in the vicinity of this pre-frontal troughing contributing to showers and thunderstorms. Modest buoyancy persists over the region, with mesoanalysis estimating MLCAPE around 500 to 750 J/kg. Showers and thunderstorms are expected to continue throughout the day as the cold front and pre-frontal troughing both shift gradually southward. The environment will remain strongly sheared (i.e. effective bulk shear around 50-55 kt) throughout the afternoon, supporting the potential for a few more organized storms capable of damaging wind gusts and perhaps even a brief tornado or two. Wind fields will weaken with southern extent, with deep-layer vertical shear weakening as well. As such, the severe potential will likely maximize this morning into the early afternoon across the central FL Peninsula. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Sun Jan 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... Strong thunderstorms may impact parts of central Florida this afternoon into early evening, and pose at least some risk for a tornado and locally damaging wind gusts. ...20z Update... The previous forecast remains on track as a line of thunderstorms continues to migrate south/southeast across the FL Peninsula. The 30-40 mph eastward motion of individual convective elements within the line is limiting residence time within the warmer/more buoyant air mass over land and favoring maximum convective intensity along Florida's east coast. Several severe wind gusts and a few 1-inch hail stones have been reported in the past couple of hours, and consideration was given for introducing 5% hail risk probabilities. However, the linear organization of the convection should limit the potential for additional supercells, and a general weakening trend is anticipated through early evening as the line continues south/southeast. It remains somewhat unclear exactly when the severe wind threat will fully diminish, especially given recent KMLB VWP observations showing 40-50 knot winds within the 2-3 km layer ahead of the convective line. To account for this uncertainty, the Marginal risk was expanded slightly southward ahead of the line, but convection should be sufficiently weak later this evening as it moves into south FL to preclude risk probabilities. ..Moore.. 01/19/2025 .PREV DISCUSSION... /ISSUED 1018 AM CST Sun Jan 19 2025/ ...FL Peninsula... Expansive upper troughing covers the entirety of the CONUS this morning, with moderate southwesterly flow aloft throughout the base of this trough extending from the Southeast/Gulf of Mexico across the Mid-Atlantic States and FL. Surface analysis places a low over central NC. A cold front extends southwestward from this low through southeast GA and the FL Big Bend. Modest troughing precedes this front across central FL, with broad low-level confluence in the vicinity of this pre-frontal troughing contributing to showers and thunderstorms. Modest buoyancy persists over the region, with mesoanalysis estimating MLCAPE around 500 to 750 J/kg. Showers and thunderstorms are expected to continue throughout the day as the cold front and pre-frontal troughing both shift gradually southward. The environment will remain strongly sheared (i.e. effective bulk shear around 50-55 kt) throughout the afternoon, supporting the potential for a few more organized storms capable of damaging wind gusts and perhaps even a brief tornado or two. Wind fields will weaken with southern extent, with deep-layer vertical shear weakening as well. As such, the severe potential will likely maximize this morning into the early afternoon across the central FL Peninsula. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0105 PM CST Sun Jan 19 2025 Valid 201200Z - 211200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR THE SAN GABRIEL MOUNTAINS WESTWARD TOWARD THE SANTA SUSANA MOUNTAINS AND SANTA MONICA MOUNTAINS...INCLUDING THE MALIBU COAST... ...CRITICAL FIRE WEATHER AREA FOR MUCH OF SOUTHERN CALIFORNIA... The primary change with this update was an expansion of the Extremely Critical highlights to the Malibu Coast. Here, the latest high-resolution guidance is in relatively good agreement, depicting 30-40 mph northeasterly surface winds (with gusts upwards of 60-70 mph) amid single-digit to lower teens RH. These dangerous fire-weather conditions will continue into Day 3/Tuesday morning. Farther south, the Critical area was also extended to the coast in Orange County and northern San Diego County, where confidence in the development of 20-30 mph northeasterly surface winds (with higher gusts) has increased. For portions of inland Orange and San Diego Counties, localized extremely critical conditions are expected -- especially over the wind-prone mountains, foothills, and valleys. For additional details, see the previous discussion below. ..Weinman.. 01/19/2025 .PREV DISCUSSION... /ISSUED 0142 AM CST Sun Jan 19 2025/ ...Synopsis... A positively tilted shortwave trough is forecast to move southward out of the Pacific Northwest and into Southern California late Sunday night into early Tuesday Morning. By Monday afternoon, strong mid-level northerly flow will reach Southern California, with an amplified mid-level ridge following behind the trough and moving east out of the Eastern Pacific. These upper-level features, in combination with strengthening surface high pressure over the Intermountain West, will result in a tight surface pressure gradient directed offshore. The pressure gradient magnitudes suggest strong Santa Ana winds developing as a result, lasting from Monday night through Tuesday morning. Recent high-resolution forecast guidance has increased the confidence in strong surface pressure gradients and strong surface winds enough to introduce an Extremely Critical area, extending from the San Gabriel Mountains westward to the Santa Monica Mountains and Santa Susana Mountains. Forecasts continue to show strong surface pressure gradients from LAX->DAG anywhere from -8 mb to -11 mb, resulting in sustained surface winds of 35-40 MPH (gusting 60-80 MPH). These dry and windy conditions, coupled with dry and receptive fuels, will result Extremely Critical conditions supportive of rapid wildfire onset and spread. Critical fire-weather highlights extend into San Diego county, where recent model guidance continues to increase confidence in strong offshore flow and dry conditions overnight Monday into Tuesday morning. ...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 0105 PM CST Sun Jan 19 2025 Valid 201200Z - 211200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR THE SAN GABRIEL MOUNTAINS WESTWARD TOWARD THE SANTA SUSANA MOUNTAINS AND SANTA MONICA MOUNTAINS...INCLUDING THE MALIBU COAST... ...CRITICAL FIRE WEATHER AREA FOR MUCH OF SOUTHERN CALIFORNIA... The primary change with this update was an expansion of the Extremely Critical highlights to the Malibu Coast. Here, the latest high-resolution guidance is in relatively good agreement, depicting 30-40 mph northeasterly surface winds (with gusts upwards of 60-70 mph) amid single-digit to lower teens RH. These dangerous fire-weather conditions will continue into Day 3/Tuesday morning. Farther south, the Critical area was also extended to the coast in Orange County and northern San Diego County, where confidence in the development of 20-30 mph northeasterly surface winds (with higher gusts) has increased. For portions of inland Orange and San Diego Counties, localized extremely critical conditions are expected -- especially over the wind-prone mountains, foothills, and valleys. For additional details, see the previous discussion below. ..Weinman.. 01/19/2025 .PREV DISCUSSION... /ISSUED 0142 AM CST Sun Jan 19 2025/ ...Synopsis... A positively tilted shortwave trough is forecast to move southward out of the Pacific Northwest and into Southern California late Sunday night into early Tuesday Morning. By Monday afternoon, strong mid-level northerly flow will reach Southern California, with an amplified mid-level ridge following behind the trough and moving east out of the Eastern Pacific. These upper-level features, in combination with strengthening surface high pressure over the Intermountain West, will result in a tight surface pressure gradient directed offshore. The pressure gradient magnitudes suggest strong Santa Ana winds developing as a result, lasting from Monday night through Tuesday morning. Recent high-resolution forecast guidance has increased the confidence in strong surface pressure gradients and strong surface winds enough to introduce an Extremely Critical area, extending from the San Gabriel Mountains westward to the Santa Monica Mountains and Santa Susana Mountains. Forecasts continue to show strong surface pressure gradients from LAX->DAG anywhere from -8 mb to -11 mb, resulting in sustained surface winds of 35-40 MPH (gusting 60-80 MPH). These dry and windy conditions, coupled with dry and receptive fuels, will result Extremely Critical conditions supportive of rapid wildfire onset and spread. Critical fire-weather highlights extend into San Diego county, where recent model guidance continues to increase confidence in strong offshore flow and dry conditions overnight Monday into Tuesday morning. ...Please see www.spc.noaa.gov/fire for graphic product... Read more