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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0205 AM CST Tue Jan 09 2024 Valid 091200Z - 101200Z ...NO CRITICAL AREAS... ...Synopsis... A strong upper-level cyclone over the southern CONUS will move eastward with the surface low moving into the mid MS Valley early this morning. Strong low-level winds should remain behind the low and the trailing cold front as it moves into the Gulf. A few hours of dry and breezy post-frontal conditions are possible across parts of deep south TX this morning through the early afternoon. Gusts of 25-30 mph with humidity below 25% may support a few hours of meteorological elevated fire-weather conditions before winds begin to weaken later in the day. However, near-normal fuel moisture and the brief overlap of the strongest dry and windy conditions suggest any fire-weather concerns will remain relatively low end and localized. ..Lyons.. 01/09/2024 ...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 0205 AM CST Tue Jan 09 2024 Valid 091200Z - 101200Z ...NO CRITICAL AREAS... ...Synopsis... A strong upper-level cyclone over the southern CONUS will move eastward with the surface low moving into the mid MS Valley early this morning. Strong low-level winds should remain behind the low and the trailing cold front as it moves into the Gulf. A few hours of dry and breezy post-frontal conditions are possible across parts of deep south TX this morning through the early afternoon. Gusts of 25-30 mph with humidity below 25% may support a few hours of meteorological elevated fire-weather conditions before winds begin to weaken later in the day. However, near-normal fuel moisture and the brief overlap of the strongest dry and windy conditions suggest any fire-weather concerns will remain relatively low end and localized. ..Lyons.. 01/09/2024 ...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 0205 AM CST Tue Jan 09 2024 Valid 091200Z - 101200Z ...NO CRITICAL AREAS... ...Synopsis... A strong upper-level cyclone over the southern CONUS will move eastward with the surface low moving into the mid MS Valley early this morning. Strong low-level winds should remain behind the low and the trailing cold front as it moves into the Gulf. A few hours of dry and breezy post-frontal conditions are possible across parts of deep south TX this morning through the early afternoon. Gusts of 25-30 mph with humidity below 25% may support a few hours of meteorological elevated fire-weather conditions before winds begin to weaken later in the day. However, near-normal fuel moisture and the brief overlap of the strongest dry and windy conditions suggest any fire-weather concerns will remain relatively low end and localized. ..Lyons.. 01/09/2024 ...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 0205 AM CST Tue Jan 09 2024 Valid 091200Z - 101200Z ...NO CRITICAL AREAS... ...Synopsis... A strong upper-level cyclone over the southern CONUS will move eastward with the surface low moving into the mid MS Valley early this morning. Strong low-level winds should remain behind the low and the trailing cold front as it moves into the Gulf. A few hours of dry and breezy post-frontal conditions are possible across parts of deep south TX this morning through the early afternoon. Gusts of 25-30 mph with humidity below 25% may support a few hours of meteorological elevated fire-weather conditions before winds begin to weaken later in the day. However, near-normal fuel moisture and the brief overlap of the strongest dry and windy conditions suggest any fire-weather concerns will remain relatively low end and localized. ..Lyons.. 01/09/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1107 PM CST Mon Jan 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Some lightning is possible in rain and snow showers near the Pacific Northwest coast and across parts of the northern Sierra Nevada into the Great Basin on Wednesday. Otherwise, the risk for thunderstorms appears negligible across much of the U.S. ...Discussion... Downstream of amplified mid/upper ridging within the split westerlies across the mid-latitude eastern Pacific, and in the wake of a broad, but weakening, cyclone migrating east-northeast of the lower Great Lakes region, cyclonic flow and seasonably low mid-level heights likely will encompass much of North America through this period. Within this regime, to the east of the ridging, a couple of notable digging short wave perturbations are forecast to contribute to amplification of the larger-scale troughing inland of the North American Pacific coast. Models indicate that one, of northern mid-latitude Pacific origins, will progress southeastward inland of the Pacific Northwest coast, through much of the Sierra Nevada and Great Basin by late Wednesday night. Another, emerging from the northern Canadian Arctic vicinity, is forecast to turn southward into the Canadian Rockies and adjacent Canadian Prairies. In lower levels, a cold front trailing the departing cyclone appears likely to continue advancing away from much of the Atlantic Seaboard, while stalling and weakening near or south of the Florida Straits/Keys into the southeastern Gulf of Mexico. At the same time, surface troughing may slowly begin to deepen to the lee of the southern Rockies through the lower Rio Grande Valley, accompanied by northward return of a moistening boundary layer across the western Gulf of Mexico. By late Wednesday night, this may include surface dew point increases to near or above 60 F, beneath relatively warm, dry and capping lower/mid-tropospheric air. Beneath a pocket of colder air aloft associated with the inland advancing short wave, which may include 500 mb temperatures around -35 C, some convection capable of producing lightning appears possible near Washington and Oregon coastal areas early Wednesday. Potential for lightning inland of coastal areas remains unclear. However, latest available forecast soundings suggest that there may be enough boundary layer warming to contribute to marginally favorable thermodynamic profiles in a corridor from near the Great Salt Lake into parts of the northern Sierra Nevada by late Wednesday afternoon, aided by mid/upper forcing for ascent. ..Kerr.. 01/09/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1107 PM CST Mon Jan 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Some lightning is possible in rain and snow showers near the Pacific Northwest coast and across parts of the northern Sierra Nevada into the Great Basin on Wednesday. Otherwise, the risk for thunderstorms appears negligible across much of the U.S. ...Discussion... Downstream of amplified mid/upper ridging within the split westerlies across the mid-latitude eastern Pacific, and in the wake of a broad, but weakening, cyclone migrating east-northeast of the lower Great Lakes region, cyclonic flow and seasonably low mid-level heights likely will encompass much of North America through this period. Within this regime, to the east of the ridging, a couple of notable digging short wave perturbations are forecast to contribute to amplification of the larger-scale troughing inland of the North American Pacific coast. Models indicate that one, of northern mid-latitude Pacific origins, will progress southeastward inland of the Pacific Northwest coast, through much of the Sierra Nevada and Great Basin by late Wednesday night. Another, emerging from the northern Canadian Arctic vicinity, is forecast to turn southward into the Canadian Rockies and adjacent Canadian Prairies. In lower levels, a cold front trailing the departing cyclone appears likely to continue advancing away from much of the Atlantic Seaboard, while stalling and weakening near or south of the Florida Straits/Keys into the southeastern Gulf of Mexico. At the same time, surface troughing may slowly begin to deepen to the lee of the southern Rockies through the lower Rio Grande Valley, accompanied by northward return of a moistening boundary layer across the western Gulf of Mexico. By late Wednesday night, this may include surface dew point increases to near or above 60 F, beneath relatively warm, dry and capping lower/mid-tropospheric air. Beneath a pocket of colder air aloft associated with the inland advancing short wave, which may include 500 mb temperatures around -35 C, some convection capable of producing lightning appears possible near Washington and Oregon coastal areas early Wednesday. Potential for lightning inland of coastal areas remains unclear. However, latest available forecast soundings suggest that there may be enough boundary layer warming to contribute to marginally favorable thermodynamic profiles in a corridor from near the Great Salt Lake into parts of the northern Sierra Nevada by late Wednesday afternoon, aided by mid/upper forcing for ascent. ..Kerr.. 01/09/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1107 PM CST Mon Jan 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Some lightning is possible in rain and snow showers near the Pacific Northwest coast and across parts of the northern Sierra Nevada into the Great Basin on Wednesday. Otherwise, the risk for thunderstorms appears negligible across much of the U.S. ...Discussion... Downstream of amplified mid/upper ridging within the split westerlies across the mid-latitude eastern Pacific, and in the wake of a broad, but weakening, cyclone migrating east-northeast of the lower Great Lakes region, cyclonic flow and seasonably low mid-level heights likely will encompass much of North America through this period. Within this regime, to the east of the ridging, a couple of notable digging short wave perturbations are forecast to contribute to amplification of the larger-scale troughing inland of the North American Pacific coast. Models indicate that one, of northern mid-latitude Pacific origins, will progress southeastward inland of the Pacific Northwest coast, through much of the Sierra Nevada and Great Basin by late Wednesday night. Another, emerging from the northern Canadian Arctic vicinity, is forecast to turn southward into the Canadian Rockies and adjacent Canadian Prairies. In lower levels, a cold front trailing the departing cyclone appears likely to continue advancing away from much of the Atlantic Seaboard, while stalling and weakening near or south of the Florida Straits/Keys into the southeastern Gulf of Mexico. At the same time, surface troughing may slowly begin to deepen to the lee of the southern Rockies through the lower Rio Grande Valley, accompanied by northward return of a moistening boundary layer across the western Gulf of Mexico. By late Wednesday night, this may include surface dew point increases to near or above 60 F, beneath relatively warm, dry and capping lower/mid-tropospheric air. Beneath a pocket of colder air aloft associated with the inland advancing short wave, which may include 500 mb temperatures around -35 C, some convection capable of producing lightning appears possible near Washington and Oregon coastal areas early Wednesday. Potential for lightning inland of coastal areas remains unclear. However, latest available forecast soundings suggest that there may be enough boundary layer warming to contribute to marginally favorable thermodynamic profiles in a corridor from near the Great Salt Lake into parts of the northern Sierra Nevada by late Wednesday afternoon, aided by mid/upper forcing for ascent. ..Kerr.. 01/09/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1156 PM CST Mon Jan 08 2024 Valid 091200Z - 101200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHERN FLORIDA AND THE FLORIDA PANHANDLE...NORTHEASTWARD ACROSS SOUTHEASTERN ALABAMA...THE SOUTHERN HALF OF GEORGIA...AND ROUGHLY THE EASTERN HALVES OF THE CAROLINAS... ...SUMMARY... Severe thunderstorms are expected impact much of the eastern Gulf and southern Atlantic Coast states today, accompanied by a risk for very strong and damaging wind gusts and a few strong tornadoes. ...East/Southeast... A strong/deepening upper low is forecast to shift east-northeastward across the Midwest/Ohio Valley area today, accompanied by a broad zone of intense deep-layer cyclonic flow that will surrounding this system. An associated/occluded surface low will shift northeastward across the Midwest toward the Upper Great Lakes, while a strong cold front expected to be crossing the Tennessee Valley/central Gulf Coast region moves quickly eastward across the East Coast States through afternoon/evening. Along the front, within an amply unstable warm sector, an organized band of strong/locally severe storms is forecast to be ongoing across the Alabama vicinity at the start of the period. Given highly favorable deep-layer shear, owing to winds increasing and veering with height through the troposphere, wind gusts locally capable of producing damage, and the possibility of strong tornadoes, will exist. Additionally, any pre-frontal, cellular storms which may evolve with time would likely become supercells, posing particular risk for a strong tornado. With time, as the line of storms advances eastward across Georgia and the Florida Panhandle through midday, some increase in low-level theta-e advection off the Gulf Stream into the Carolinas is expected. This will act to partially offset the widespread/ongoing cloud cover and showery precipitation across this area, to allow some surface-based destabilization of the warm sector to occur. Eventual development of pre-frontal, cellular convection may gradually evolve as a result, which -- given the extremely strong deep-layer wind field -- would likely yield a secondary area of higher-probability tornado risk, to include the potential for strong tornadoes. Meanwhile, strong/damaging wind gusts are expected across the East Coast states as far north as southeastern Virginia, as bands of storms accompany frontal passage across this area through the afternoon and evening hours. ..Goss/Lyons.. 01/09/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1156 PM CST Mon Jan 08 2024 Valid 091200Z - 101200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHERN FLORIDA AND THE FLORIDA PANHANDLE...NORTHEASTWARD ACROSS SOUTHEASTERN ALABAMA...THE SOUTHERN HALF OF GEORGIA...AND ROUGHLY THE EASTERN HALVES OF THE CAROLINAS... ...SUMMARY... Severe thunderstorms are expected impact much of the eastern Gulf and southern Atlantic Coast states today, accompanied by a risk for very strong and damaging wind gusts and a few strong tornadoes. ...East/Southeast... A strong/deepening upper low is forecast to shift east-northeastward across the Midwest/Ohio Valley area today, accompanied by a broad zone of intense deep-layer cyclonic flow that will surrounding this system. An associated/occluded surface low will shift northeastward across the Midwest toward the Upper Great Lakes, while a strong cold front expected to be crossing the Tennessee Valley/central Gulf Coast region moves quickly eastward across the East Coast States through afternoon/evening. Along the front, within an amply unstable warm sector, an organized band of strong/locally severe storms is forecast to be ongoing across the Alabama vicinity at the start of the period. Given highly favorable deep-layer shear, owing to winds increasing and veering with height through the troposphere, wind gusts locally capable of producing damage, and the possibility of strong tornadoes, will exist. Additionally, any pre-frontal, cellular storms which may evolve with time would likely become supercells, posing particular risk for a strong tornado. With time, as the line of storms advances eastward across Georgia and the Florida Panhandle through midday, some increase in low-level theta-e advection off the Gulf Stream into the Carolinas is expected. This will act to partially offset the widespread/ongoing cloud cover and showery precipitation across this area, to allow some surface-based destabilization of the warm sector to occur. Eventual development of pre-frontal, cellular convection may gradually evolve as a result, which -- given the extremely strong deep-layer wind field -- would likely yield a secondary area of higher-probability tornado risk, to include the potential for strong tornadoes. Meanwhile, strong/damaging wind gusts are expected across the East Coast states as far north as southeastern Virginia, as bands of storms accompany frontal passage across this area through the afternoon and evening hours. ..Goss/Lyons.. 01/09/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1156 PM CST Mon Jan 08 2024 Valid 091200Z - 101200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHERN FLORIDA AND THE FLORIDA PANHANDLE...NORTHEASTWARD ACROSS SOUTHEASTERN ALABAMA...THE SOUTHERN HALF OF GEORGIA...AND ROUGHLY THE EASTERN HALVES OF THE CAROLINAS... ...SUMMARY... Severe thunderstorms are expected impact much of the eastern Gulf and southern Atlantic Coast states today, accompanied by a risk for very strong and damaging wind gusts and a few strong tornadoes. ...East/Southeast... A strong/deepening upper low is forecast to shift east-northeastward across the Midwest/Ohio Valley area today, accompanied by a broad zone of intense deep-layer cyclonic flow that will surrounding this system. An associated/occluded surface low will shift northeastward across the Midwest toward the Upper Great Lakes, while a strong cold front expected to be crossing the Tennessee Valley/central Gulf Coast region moves quickly eastward across the East Coast States through afternoon/evening. Along the front, within an amply unstable warm sector, an organized band of strong/locally severe storms is forecast to be ongoing across the Alabama vicinity at the start of the period. Given highly favorable deep-layer shear, owing to winds increasing and veering with height through the troposphere, wind gusts locally capable of producing damage, and the possibility of strong tornadoes, will exist. Additionally, any pre-frontal, cellular storms which may evolve with time would likely become supercells, posing particular risk for a strong tornado. With time, as the line of storms advances eastward across Georgia and the Florida Panhandle through midday, some increase in low-level theta-e advection off the Gulf Stream into the Carolinas is expected. This will act to partially offset the widespread/ongoing cloud cover and showery precipitation across this area, to allow some surface-based destabilization of the warm sector to occur. Eventual development of pre-frontal, cellular convection may gradually evolve as a result, which -- given the extremely strong deep-layer wind field -- would likely yield a secondary area of higher-probability tornado risk, to include the potential for strong tornadoes. Meanwhile, strong/damaging wind gusts are expected across the East Coast states as far north as southeastern Virginia, as bands of storms accompany frontal passage across this area through the afternoon and evening hours. ..Goss/Lyons.. 01/09/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1156 PM CST Mon Jan 08 2024 Valid 091200Z - 101200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHERN FLORIDA AND THE FLORIDA PANHANDLE...NORTHEASTWARD ACROSS SOUTHEASTERN ALABAMA...THE SOUTHERN HALF OF GEORGIA...AND ROUGHLY THE EASTERN HALVES OF THE CAROLINAS... ...SUMMARY... Severe thunderstorms are expected impact much of the eastern Gulf and southern Atlantic Coast states today, accompanied by a risk for very strong and damaging wind gusts and a few strong tornadoes. ...East/Southeast... A strong/deepening upper low is forecast to shift east-northeastward across the Midwest/Ohio Valley area today, accompanied by a broad zone of intense deep-layer cyclonic flow that will surrounding this system. An associated/occluded surface low will shift northeastward across the Midwest toward the Upper Great Lakes, while a strong cold front expected to be crossing the Tennessee Valley/central Gulf Coast region moves quickly eastward across the East Coast States through afternoon/evening. Along the front, within an amply unstable warm sector, an organized band of strong/locally severe storms is forecast to be ongoing across the Alabama vicinity at the start of the period. Given highly favorable deep-layer shear, owing to winds increasing and veering with height through the troposphere, wind gusts locally capable of producing damage, and the possibility of strong tornadoes, will exist. Additionally, any pre-frontal, cellular storms which may evolve with time would likely become supercells, posing particular risk for a strong tornado. With time, as the line of storms advances eastward across Georgia and the Florida Panhandle through midday, some increase in low-level theta-e advection off the Gulf Stream into the Carolinas is expected. This will act to partially offset the widespread/ongoing cloud cover and showery precipitation across this area, to allow some surface-based destabilization of the warm sector to occur. Eventual development of pre-frontal, cellular convection may gradually evolve as a result, which -- given the extremely strong deep-layer wind field -- would likely yield a secondary area of higher-probability tornado risk, to include the potential for strong tornadoes. Meanwhile, strong/damaging wind gusts are expected across the East Coast states as far north as southeastern Virginia, as bands of storms accompany frontal passage across this area through the afternoon and evening hours. ..Goss/Lyons.. 01/09/2024 Read more

The Dorena-Hickman Ferry was closed again due to the low level of the Mississippi River. The ferry reopened last week after being closed since August 23, due to drought and low water levels. This closure, however, was expected to be brief. As of Monday at 7 a.m., the Cairo gauge was at 13.47 feet, just below 14 feet which is typically required for the ferry to operate, according to Kentucky Transportation Cabinet District 1. WSIL-TV ABC 3 (Harrisburg, Ill.), Jan 8, 2024

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 AM CST Mon Jan 08 2024 Valid 091200Z - 101200Z ...NO CRITICAL AREAS... ...Synopsis... The strong upper-level trough over the southern Plains will begin to move eastward with the surface cyclone moving into the Mid-MS Valley early in the period. Strong low-level wind fields should remain behind the low and the trailing cold front across the southern Plains. A few hours of dry and breezy post-frontal conditions are possible across parts of south TX into the afternoon ahead of the colder air mass moving south. Gusts of 25-30 mph with humidity below 25% may support a few hours of elevated meteorological conditions. However, poor fuel availability and the brief overlap of dry and windy conditions suggest any fire-weather concerns will remain localized. ..Lyons.. 01/08/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Mon Jan 8 08:05:01 UTC 2024.

No Mesoscale Discussions are in effect as of Mon Jan 8 08:05:01 UTC 2024.

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Mon Jan 08 2024 Valid 081200Z - 091200Z ...NO CRITICAL AREAS... ...Synopsis... An impressive upper trough will eject eastward over the southern Plains will undergoing significant amplification through the forecast period. with a deepening surface cyclone expected over parts of OK and North TX. Strong southwest winds behind the low are expected to develop across parts of West TX and the Big Bend along with lower humidity. While area fuels are not expected to be overly dry, a few hours of elevated to locally critical meteorological conditions are possible. ...Texas Big Bend... As the strong surface cyclone over OK continues to deepen, west/southwest downslope flow will gradually develop over West TX and the Big Bend region. Aided by strong mid-level flow ahead of the approaching trough, gusts of 30-40 mph are possible through the afternoon. RH values below 20% are also possible within the dry warm sector of the strengthening cyclone. A few hours of overlap of dry and windy surface conditions should support elevated to locally critical meteorological conditions across parts of the TX Big Bend region. However, area fuels are not particularly receptive given recent freezes and near normal fuel moisture. While a few hours of localized fire-concerns are possible, widespread critical conditions appear unlikely. ..Lyons.. 01/08/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0158 AM CST Mon Jan 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across much of the U.S., Wednesday through Wednesday night. ...Discussion... In the wake of a broad, but weakening, cyclone forecast to slowly migrate east-northeast of the lower Great Lakes region, and downstream of amplified ridging within the split westerlies across the eastern mid-latitude Pacific, mid-level troughing appears likely to encompass much of North America through this period. A couple of significant short wave perturbations digging to the east of the ridging will contribute to the maintenance of this troughing. One, emerging from the northern mid-latitude Pacific, is forecast to progress inland of Pacific Northwest through the Sierra Nevada into eastern Great Basin/Colorado Plateau vicinity by 12Z Thursday. Another, emerging from the northern Canadian Arctic vicinity, is forecast to turn southward into the Canadian Prairies and Rockies. In lower levels, a cold front trailing the lead cyclone appears likely to advance away from much of the Atlantic Seaboard, while stalling and weakening near the Florida Straits/Keys vicinity through the southeastern Gulf of Mexico. At the same time, surface troughing may begin to deepen to the lee of the southern Rockies through the lower Rio Grande Valley, accompanied by modest boundary layer moistening and northward return across the western Gulf of Mexico. This may include surface dew point increases to around 60F near Texas coastal areas by late Wednesday night, beneath relatively warm, dry and capping lower/mid-tropospheric air. Beneath cold air across the Pacific Northwest, which may include an inland spreading cold core (around -35 C at 500 mb), some convection capable of producing lightning appears possible near coastal areas early in the period. Inland of the coast, probabilities for lightning appear increasingly negligible, due to a lingering generally cooler and drier boundary layer. However, convection with a flash or two of lightning might not be out of the question across parts of the northern Sierra Nevada and Sacramento Valley Wednesday afternoon and evening. ..Kerr.. 01/08/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1146 PM CST Sun Jan 07 2024 Valid 091200Z - 101200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS TUESDAY ACROSS PARTS OF SOUTHEASTERN ALABAMA...NORTHERN FLORIDA...PARTS OF THE CAROLINA PIEDMONT AND THE CAROLINA COASTAL PLAIN... ...SUMMARY... Severe thunderstorms may impact much of the eastern Gulf and southern Atlantic Coast states Tuesday, accompanied by a risk for very strong and damaging wind gusts and a few strong tornadoes. ...Synopsis... Within the prevailing split flow across the eastern mid-latitude Pacific, it still appears that mid/upper ridging will undergo amplification through this period. As this occurs, mid-level troughing is forecast to begin to dig across Pacific Northwest, and a strong downstream trough, initially approaching the Mississippi Valley, likely will remain progressive. Strong cyclogenesis appears likely to proceed from the Mississippi Valley through much of the eastern U.S., with the center of the primary surface cyclone generally forecast to track from east central Missouri through lower Michigan by late Tuesday night. Models indicate that the mid/upper trough axis will take on a negative tilt while pivoting northeast of the Mississippi Valley, with difluent flow aloft overspreading much of the Southeast. Further intensification of lower/mid-tropospheric wind fields may include 50-90+ kt southerly to southwesterly flow in the 850-700 mb layer overspreading much of the eastern Gulf/southern Atlantic Coast region during the day Tuesday, accompanied by a moistening warm sector. ...Southeast... Associated with the strong synoptic forcing for ascent, a strong to severe squall line, perhaps closely preceded by discrete supercell development, may be ongoing ahead of an eastward surging cold front across parts of central/southern Alabama into the north central Gulf of Mexico at 12Z Tuesday. With at least a continuing corridor of sufficient pre-frontal destabilization, the forcing for ascent likely will maintain this convective development across much of the eastern Gulf/southern Atlantic Coast region by Tuesday evening. While inflow off the Atlantic into the Carolinas will contribute to pre-frontal low-level moistening even if the Gulf moist inflow becomes cut off, relatively warm layers aloft with weak lapse rates model likely will tend to at least limit the degree of boundary-layer destabilization. However, latest forecast soundings from both the 03Z Rapid Refresh and NAM do appear to suggest that thermodynamic profiles immediately ahead of the line will continue to become at least marginally sufficient to maintain a line of surface-based or near surface-based storms. It is still possible that the line of convection may undergo at least some weakening across parts of Georgia and Florida during the morning or early afternoon, before intensifying once again across the Carolinas. However, given mean winds forecast on the order of 60-70+ kts in the lowest 6 km, downward mixing of higher momentum may remain sufficient to support widespread strong, damaging wind gusts. Given the strong to extreme low-level shear, developing meso-vortices within the line may pose a risk for tornadoes. Within the moistening return flow off the Atlantic, there is at least some signal within convection allowing guidance of increasing potential for discrete supercell development across the Carolina coastal plain by late Tuesday afternoon, aided by large-scale ascent associated with warm advection ahead of the squall line. In the presence of potentially very large, clockwise-curved low-level hodographs, this may be accompanied by the risk for a couple of strong tornadoes. It remains unclear how much of a focus a remnant baroclinic zone, extending through much of the eastern Georgia and Carolina Piedmont, may become for severe thunderstorm development. ..Kerr.. 01/08/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1146 PM CST Sun Jan 07 2024 Valid 091200Z - 101200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS TUESDAY ACROSS PARTS OF SOUTHEASTERN ALABAMA...NORTHERN FLORIDA...PARTS OF THE CAROLINA PIEDMONT AND THE CAROLINA COASTAL PLAIN... ...SUMMARY... Severe thunderstorms may impact much of the eastern Gulf and southern Atlantic Coast states Tuesday, accompanied by a risk for very strong and damaging wind gusts and a few strong tornadoes. ...Synopsis... Within the prevailing split flow across the eastern mid-latitude Pacific, it still appears that mid/upper ridging will undergo amplification through this period. As this occurs, mid-level troughing is forecast to begin to dig across Pacific Northwest, and a strong downstream trough, initially approaching the Mississippi Valley, likely will remain progressive. Strong cyclogenesis appears likely to proceed from the Mississippi Valley through much of the eastern U.S., with the center of the primary surface cyclone generally forecast to track from east central Missouri through lower Michigan by late Tuesday night. Models indicate that the mid/upper trough axis will take on a negative tilt while pivoting northeast of the Mississippi Valley, with difluent flow aloft overspreading much of the Southeast. Further intensification of lower/mid-tropospheric wind fields may include 50-90+ kt southerly to southwesterly flow in the 850-700 mb layer overspreading much of the eastern Gulf/southern Atlantic Coast region during the day Tuesday, accompanied by a moistening warm sector. ...Southeast... Associated with the strong synoptic forcing for ascent, a strong to severe squall line, perhaps closely preceded by discrete supercell development, may be ongoing ahead of an eastward surging cold front across parts of central/southern Alabama into the north central Gulf of Mexico at 12Z Tuesday. With at least a continuing corridor of sufficient pre-frontal destabilization, the forcing for ascent likely will maintain this convective development across much of the eastern Gulf/southern Atlantic Coast region by Tuesday evening. While inflow off the Atlantic into the Carolinas will contribute to pre-frontal low-level moistening even if the Gulf moist inflow becomes cut off, relatively warm layers aloft with weak lapse rates model likely will tend to at least limit the degree of boundary-layer destabilization. However, latest forecast soundings from both the 03Z Rapid Refresh and NAM do appear to suggest that thermodynamic profiles immediately ahead of the line will continue to become at least marginally sufficient to maintain a line of surface-based or near surface-based storms. It is still possible that the line of convection may undergo at least some weakening across parts of Georgia and Florida during the morning or early afternoon, before intensifying once again across the Carolinas. However, given mean winds forecast on the order of 60-70+ kts in the lowest 6 km, downward mixing of higher momentum may remain sufficient to support widespread strong, damaging wind gusts. Given the strong to extreme low-level shear, developing meso-vortices within the line may pose a risk for tornadoes. Within the moistening return flow off the Atlantic, there is at least some signal within convection allowing guidance of increasing potential for discrete supercell development across the Carolina coastal plain by late Tuesday afternoon, aided by large-scale ascent associated with warm advection ahead of the squall line. In the presence of potentially very large, clockwise-curved low-level hodographs, this may be accompanied by the risk for a couple of strong tornadoes. It remains unclear how much of a focus a remnant baroclinic zone, extending through much of the eastern Georgia and Carolina Piedmont, may become for severe thunderstorm development. ..Kerr.. 01/08/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1154 PM CST Sun Jan 07 2024 Valid 081200Z - 091200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL GULF COAST TONIGHT INTO EARLY TUESDAY MORNING... ...SUMMARY... Severe thunderstorms capable of strong wind gusts and tornadoes are expected from southeast Texas across the central Gulf Coast this afternoon into early Tuesday morning. Greatest severe potential is anticipated overnight from southeast Louisiana across southern Mississippi and southern Alabama, and into the western Florida Panhandle. ...Synopsis... A potent, positive-tilt mid-level shortwave centered over the Four Corners will undergo significant amplification as it emerges over the Southern Plains through the forecast period. South of the primary vort max, a 90-100 kt H5 jet streak will round the base of the trough and move quickly eastward, intensifying further, as it overspreads the mid-MS valley into early Tuesday. Coincident with the robust forcing aloft, a lee cyclone over northeast NM will quickly deepen below 1000 mb as it tracks eastward over the TX Panhandle and OK. South of the low, strong low-level mass response will rapidly advect a modifying Gulf air mass northward into portions of central/southeast TX and eventually across the central Gulf Coast. Strong low-level warm advection ahead of the intensifying upper-level and surface cyclone will support numerous showers and thunderstorms across the southern Plains and lower MS Valley today into early morning Tuesday. Strong kinematics and sufficient buoyancy within the onshore warm sector will support organized storms capable of all hazards, including a couple strong tornadoes. ...North TX into the ArkLaTex... Showers and embedded thunderstorms should be ongoing early this morning within a strong low-level warm advection regime ahead of the surface low and cold front in western north TX/OK. Area model soundings show weak and elevated buoyancy profiles atop a mostly stable surface layer ahead of the deeper returning surface moisture. Despite the marginal buoyancy, a narrow line of forced convection may evolve along the cold front and become capable of locally gusty/damaging wind gusts as it moves eastward from north TX into far southern AR and northern LA. ...Southeast TX to southwest LA... As the surface low continues to deepen over OK and western North TX, strong low-level mass response will rapidly draw a modifying Gulf air mass northward into south-central and southeast TX. Surface dewpoints will gradually rise into the low to mid 60s F as the air mass moves farther inland. Widespread cloud cover and warm advection showers will limit solar heating, but inhibition should weaken through the early afternoon as deep-layer ascent increases and gradual warming of the boundary layer supports 1200-2000 J/kg of MLCAPE. Scattered thunderstorms should gradually evolve from the initial low-topped showers within increasingly strong low-level and deep-layer shear profiles sufficient for supercells. A secondary surface low along the advancing warm front may also locally back surface winds, favoring strong low-level mesocyclones with the potential for damaging gusts and a few tornadoes. Additional storms are likely to develop later in the afternoon as the surface cold front approaches from the west. Behind the secondary surface low, veered low-level flow suggests a more linear orientation may evolve with upscale growth of the new convection into a broken line/QLCS with greater potential for damaging wind gusts. Still, 0-1 km shear in excess of 30 kt may support some risk for line embedded circulations with enhanced damaging gust or tornado potential into the evening and overnight hours. ...Central Gulf Coast tonight into early Tuesday... An initial round of elevated showers and thunderstorms is expected to develop by early to mid afternoon over parts of the central Gulf coast ahead of the warm front moving onshore. As the Gulf air mass gradually moves inland, increasing surface dewpoints will allow for moderate buoyancy to develop coincident with a strong increase in mid and low-level shear profiles ahead of the advancing upper trough. A 60-70 kt low-level jet will continue to support strong warm advection and the development of additional thunderstorms ahead of the main convective line to the west into the evening and overnight hours. A few supercells may evolve ahead of the line over parts of southern MS, southwest AL and the western FL Panhandle within a very strongly sheared environment. STP values of 3-5 on area model soundings suggest the potential for a couple of strong tornadoes. Damaging wind gusts and line-embedded tornadoes also appear likely as the QLCS advances quickly from west to east. ..Lyons/Grams.. 01/08/2024 Read more