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SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 PM CDT Tue Sep 24 2024 Valid 261200Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF THE FLORIDA PENINSULA...SOUTHEAST GEORGIA...AND SOUTHERN SOUTH CAROLINA... ...SUMMARY... Tropical Cyclone Helene is forecast to move inland across northern Florida and Georgia on Thursday. A risk for tropical-cyclone tornadoes will accompany this system, particularly from the central Florida Peninsula into southeast Georgia and southern South Carolina. ...FL/GA/SC - Tropical Cyclone Helene... Tropical Cyclone Helene is forecast to be a major hurricane in the eastern Gulf of Mexico early Thursday morning. Current forecast track from the National Hurricane Center takes this system quickly north-northeastward to the FL Big Bend vicinity by 00Z Friday before it then tracks more north-northwesterly into northern GA by 12Z Friday. This progression places the much of the FL Peninsula, central to southeast GA, and much of SC with the eastern semi-circle of the storm during the period. A preceding maritime tropical airmass is already in place, with additional moistening anticipated as the storm moves through. This favorable low-level moisture is expected to result in at least modest buoyancy capable of supporting deeper, more persistent updrafts. Intense low to mid-level wind fields will be colocated with this buoyancy, contributing to increased chance for tropical-cyclone related tornadoes. ..Mosier.. 09/24/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 PM CDT Tue Sep 24 2024 Valid 261200Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF THE FLORIDA PENINSULA...SOUTHEAST GEORGIA...AND SOUTHERN SOUTH CAROLINA... ...SUMMARY... Tropical Cyclone Helene is forecast to move inland across northern Florida and Georgia on Thursday. A risk for tropical-cyclone tornadoes will accompany this system, particularly from the central Florida Peninsula into southeast Georgia and southern South Carolina. ...FL/GA/SC - Tropical Cyclone Helene... Tropical Cyclone Helene is forecast to be a major hurricane in the eastern Gulf of Mexico early Thursday morning. Current forecast track from the National Hurricane Center takes this system quickly north-northeastward to the FL Big Bend vicinity by 00Z Friday before it then tracks more north-northwesterly into northern GA by 12Z Friday. This progression places the much of the FL Peninsula, central to southeast GA, and much of SC with the eastern semi-circle of the storm during the period. A preceding maritime tropical airmass is already in place, with additional moistening anticipated as the storm moves through. This favorable low-level moisture is expected to result in at least modest buoyancy capable of supporting deeper, more persistent updrafts. Intense low to mid-level wind fields will be colocated with this buoyancy, contributing to increased chance for tropical-cyclone related tornadoes. ..Mosier.. 09/24/2024 Read more

Officials in Edinburg issued a city ordinance to limit car washes to conserve water and encourage sustainability. Water levels in the Rio Grande Valley were at a historical low, prompting local leaders to declare emergency orders amid the ongoing drought. Brownsville issued a city ordinance in April restricting new car washes from being built within five miles of each other. ValleyCentral.com (Brownsville, Texas), Sept 24, 2024

MD 2101 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR EASTERN WEST VIRGINIA SOUTH TO NORTHEASTERN TENNESSEE/WESTERN NORTH CAROLINA
Mesoscale Discussion 2101 NWS Storm Prediction Center Norman OK 1255 PM CDT Tue Sep 24 2024 Areas affected...eastern West Virginia south to northeastern Tennessee/western North Carolina Concerning...Severe potential...Watch unlikely Valid 241755Z - 241900Z Probability of Watch Issuance...20 percent SUMMARY...Local risk for severe weather is evident in the short term, where WW issuance may be needed. DISCUSSION...While persistent/dense cloud cover is apparent in visible satellite imagery east of the mountains in Virginia, heating is ongoing across eastern West Virginia and areas south, where clouds are more sparse. This has resulted in a narrow axis of moderate destabilization (1000 to 1500 J/kg mixed-layer CAPE). The destabilizing environment has supported a zone of convective development -- including a small/organized band of intense storms moving across portions of eastern West Virginia. Given the cloud cover/low-level stability across the mountains into the eastern West Virginia/western Maryland Panhandles and adjacent western Virginia, these storms should begin to weaken in the next hour or so as they shift eastward. Farther south however, a broader zone of destabilization may support a longer-duration risk for strong storms this afternoon. However, risk for severe weather should remain localized, and at this time it appears that WW issuance may not be required. ..Goss/Guyer.. 09/24/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LWX...RNK...PBZ...RLX...GSP...MRX... LAT...LON 39527966 39107939 37538021 35758132 35348300 36618309 38018131 39158047 39618014 39527966 Read more

MD 2100 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF WESTERN AND MIDDLE TENNESSEE...PART OF WESTERN AND CENTRAL KENTUCKY...SOUTHEASTERN INDIANA...AND SOUTHWESTERN OHIO
Mesoscale Discussion 2100 NWS Storm Prediction Center Norman OK 1153 AM CDT Tue Sep 24 2024 Areas affected...portions of western and Middle Tennessee...part of western and central Kentucky...southeastern Indiana...and southwestern Ohio Concerning...Severe potential...Watch possible Valid 241653Z - 241900Z Probability of Watch Issuance...60 percent SUMMARY...Convective coverage/intensity should continue to ramp up through early afternoon, with severe threat to gradually increase. WW issuance may be required. DISCUSSION...Latest visible satellite loop shows broken cloud cover across the lower Ohio and Tennessee Valleys, in the wake of earlier convection. This has allowed modest destabilization to commence ahead of the advancing cold front, with an axis of 1500 J/kg mixed-layer CAPE now extending from southern Indiana south-southwestward across parts of western and Middle Tennessee. In response to the destabilizing environment, and ascent in the vicinity of the front, a gradual convective increase is noted on radar and visible satellite loops, which should continue over the next couple of hours as modest/continued heating/destabilization occur. On the southeastern fringe of the advancing trough (across the Ohio and Tennessee Valley areas), moderately strong southwesterly flow aloft is indicated, which will aid in storm intensification resulting in eventually multicell and potentially isolated supercell storms. As this occurs, risk for locally damaging wind gusts, and some hail, will increase with stronger storms/storm clusters. Given the evolving severe-weather potential, a severe thunderstorm watch may be needed in the next hour or so. ..Goss/Guyer.. 09/24/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILN...LMK...OHX...IND...PAH...MEG... LAT...LON 39698439 39118392 38178454 36088607 35228713 35078895 35678894 36438855 37718705 38608639 39528553 39698439 Read more

000
ABPZ20 KNHC 241754
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Tue Sep 24 2024

For the eastern North Pacific...east of 140 degrees west longitude:

Active Systems:
The National Hurricane Center has issued its last advisory on
Tropical Storm John, dissipated inland over southern Mexico.

Offshore of Southern Mexico:
A trough of low pressure, partially associated with the remnants of
John, is producing a large area of showers and thunderstorms along
the coast of southern Mexico. Environmental conditions appear
conducive for some development of this system and a tropical
depression could form in the next couple of days or so, depending on
if it stays over water. Interests in southern Mexico should monitor
the progress of this system. Regardless of development, this system
is expected to produce heavy rainfall and the potential for flash
flooding and mudslides over portions of southern Mexico this week.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 7 days...medium...50 percent.

$$
Forecaster Bucci/Cangialosi

5-Day Uncertainty Track last updated Tue, 24 Sep 2024 17:49:30 GMT


Wind Speed Probabilities last updated Tue, 24 Sep 2024 17:49:31 GMT

Issued at 1200 PM CST Tue Sep 24 2024 000 WTPZ45 KNHC 241748 TCDEP5 Remnants Of John Special Discussion Number 10 NWS National Hurricane Center Miami FL EP102024 1200 PM CST Tue Sep 24 2024 Satellite images and surface observations indicate that the low-level center of John has dissipated. Therefore, the system is no longer a tropical cyclone, and this is the last NHC advisory. However, an elongated trough partly associated with John's remnants appears to be forming off the coast of southern and southwestern Mexico. This system is now included in the Tropical Weather Outlook with a medium chance of development. Regardless of whether or not John re-forms or a new system develops, heavy rainfall with the potential for significant flooding is likely during the next several days over portions of southern and southwestern Mexico, especially in areas of high terrain. FORECAST POSITIONS AND MAX WINDS INIT 24/1800Z 17.7N 100.6W 30 KT 35 MPH 12H 25/0000Z...DISSIPATED $$ Forecaster Cangialosi/Bucci

Issued at 1800 UTC TUE SEP 24 2024 000 FOPZ15 KNHC 241747 PWSEP5 REMNANTS OF JOHN SPECIAL WIND SPEED PROBABILITIES NUMBER 10 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102024 1800 UTC TUE SEP 24 2024 AT 1800Z THE REMNANTS OF JOHN WERE LOCATED NEAR LATITUDE 17.7 NORTH ...LONGITUDE 100.6 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 30 KTS... 35 MPH...55 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 12Z TUE AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 12Z TUE 00Z WED 12Z WED 00Z THU 12Z THU 12Z FRI 12Z SAT PERIODS TO TO TO TO TO TO TO 00Z WED 12Z WED 00Z THU 12Z THU 12Z FRI 12Z SAT 12Z SUN FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT ZIHUATANEJO 34 7 1( 8) X( 8) X( 8) X( 8) X( 8) X( 8) $$ FORECASTER CANGIALOSI

Issued at 1200 PM CST Tue Sep 24 2024 000 WTPZ35 KNHC 241747 TCPEP5 BULLETIN Remnants Of John Special Advisory Number 10 NWS National Hurricane Center Miami FL EP102024 1200 PM CST Tue Sep 24 2024 ...JOHN DISSIPATES OVER MEXICO... ...HEAVY RAINS STILL EXPECTED TO CAUSE FLASH FLOODING OVER SOUTHERN AND SOUTHWESTERN MEXICO FOR SEVERAL MORE DAYS... SUMMARY OF 1200 PM CST...1800 UTC...INFORMATION ----------------------------------------------- LOCATION...17.7N 100.6W ABOUT 70 MI...115 KM NW OF ACAPULCO MEXICO MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...WNW OR 300 DEGREES AT 3 MPH...6 KM/H MINIMUM CENTRAL PRESSURE...1004 MB...29.65 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: The government of Mexico has discontinued all Tropical Storm Warnings. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1200 PM CST (1800 UTC), the remnants of John were located inland near latitude 17.7 North, longitude 100.6 West. The remnants are moving toward the west-northwest near 3 mph (6 km/h). Maximum sustained winds are near 35 mph (55 km/h) with higher gusts. The estimated minimum central pressure is 1004 mb (29.65 inches). HAZARDS AFFECTING LAND ---------------------- RAINFALL: Through Thursday, the remnants of John are expected to produce 6 to 12 inches of rain with isolated totals around 15 inches across the coastal areas of Chiapas. In areas along and near the Oaxaca coast to southeast Guerrero, between 10 and 20 inches of rain with isolated totals near 30 inches can be expected through Thursday. NEXT ADVISORY ------------- This is the last public advisory issued by the National Hurricane Center on this system. Information on possible tropical cyclone development off the coast of Mexico will be contained in the Tropical Weather Outlook issued by the National Hurricane Center. $$ Forecaster Cangialosi/Bucci

...JOHN DISSIPATES OVER MEXICO... ...HEAVY RAINS STILL EXPECTED TO CAUSE FLASH FLOODING OVER SOUTHERN AND SOUTHWESTERN MEXICO FOR SEVERAL MORE DAYS... As of 12:00 PM CST Tue Sep 24 the center of John was located near 17.7, -100.6 with movement WNW at 3 mph. The minimum central pressure was 1004 mb with maximum sustained winds of about 35 mph.

Issued at 1800 UTC TUE SEP 24 2024 000 WTPZ25 KNHC 241747 TCMEP5 REMNANTS OF JOHN SPECIAL FORECAST/ADVISORY NUMBER 10 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102024 1800 UTC TUE SEP 24 2024 REMNANTS OF CENTER LOCATED NEAR 17.7N 100.6W AT 24/1800Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 300 DEGREES AT 3 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1004 MB MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 17.7N 100.6W AT 24/1800Z AT 24/1200Z CENTER WAS LOCATED NEAR 17.7N 100.3W FORECAST VALID 25/0000Z..DISSIPATED THIS IS THE LAST FORECAST/ADVISORY ISSUED BY THE NATIONAL HURRICANE CENTER ON THIS SYSTEM $$ FORECASTER CANGIALOSI/BUCCI

WW 0681 Status Updates
STATUS FOR WATCH 0681 HAS NOT BEEN ISSUED YET Read more

WW 0681 Status Updates
STATUS FOR WATCH 0681 HAS NOT BEEN ISSUED YET Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 24 2024 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST ALABAMA INTO THE WESTERN FLORIDA PANHANDLE...AND ACROSS MUCH OF THE FLORIDA PENINSULA... ...SUMMARY... Isolated severe thunderstorms capable of damaging gusts and/or brief tornadoes are possible from southeast Alabama into the western Florida Panhandle, and across much of the Florida Peninsula. ...Synopsis... An amplified upper pattern, featuring a ridge extended from northern Mexico through the northern High Plains and a trough extended from Ontario into the Lower MS Valley, will cover the CONUS early Wednesday. Bifurcation of the upper trough is anticipated throughout the period, with a northern shortwave trough remaining progressive as it moves across eastern Ontario into southern Quebec, and a southern upper low stalling over the Mid-South vicinity. The stalling of the southern upper low will occur as subtropical ridging builds across the western Atlantic and a tropical cyclone enters the eastern Gulf of Mexico. Latest forecast guidance from NHC for this tropical cyclone, which was recently upgraded to Tropical Storm Helene, suggests the storm will reach hurricane strength during the day Wednesday, with additional strengthening to major hurricane strength by early Thursday morning. Farther west, a progressive shortwave trough is forecast to move quickly across southern British Columbia and the Pacific Northwest, ending the period over the northern Rockies. At the surface, a weak front will likely extend from a low over the Lake Huron vicinity southward through middle TN before arcing more southwestward to another low in southeast TX. Western portion of this front over TX and LA is forecast to remain progressive, pushing southeastward to the western Gulf Coast by Wednesday evening. Eastern portion of the front will stall, maintaining a more north-south orientation from northern AL through southern Lower MI. ...Upper OH Valley through the southern Appalachians into AL, GA, and FL Panhandle Wednesday morning into the evening... A belt of enhanced southwesterly flow aloft is forecast to extend through the eastern periphery of the upper low developing over the Mid-South from the FL Panhandle northward into the Upper OH Valley. Widespread showers and thunderstorms are anticipated within this warm conveyor, reaching as far north as western A. However, poor lapse rates and limited destabilization should mitigate the overall severe potential across the majority of this region. An area of locally higher severe potential is anticipated within a spatially constrained corridor from southeast AL into far southwest GA and the western FL Panhandle, just west of the primary axis of precipitation anticipated within the warm conveyor. Here, a mix of low 70s dewpoints, modest heating, and moderate mid-level flow could result in a few thunderstorms capable of damaging gusts and/or a brief tornado or two. ...Much of the FL Peninsula... Rainbands associated with tropical cyclone Helene are forecast to move across the FL Peninsula throughout the period. At the same time, low to mid-level flow attendant to the cyclone will increase as the cyclone and its expansive wind field spread northward. As a result, vertical shear will be strong enough to support organized storm structure. Primary mitigating factor is warm, poor lapse rate profiles that limit buoyancy. Brief tornadoes will be possible within any updrafts that are able to mature/persist. ..Mosier.. 09/24/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 24 2024 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST ALABAMA INTO THE WESTERN FLORIDA PANHANDLE...AND ACROSS MUCH OF THE FLORIDA PENINSULA... ...SUMMARY... Isolated severe thunderstorms capable of damaging gusts and/or brief tornadoes are possible from southeast Alabama into the western Florida Panhandle, and across much of the Florida Peninsula. ...Synopsis... An amplified upper pattern, featuring a ridge extended from northern Mexico through the northern High Plains and a trough extended from Ontario into the Lower MS Valley, will cover the CONUS early Wednesday. Bifurcation of the upper trough is anticipated throughout the period, with a northern shortwave trough remaining progressive as it moves across eastern Ontario into southern Quebec, and a southern upper low stalling over the Mid-South vicinity. The stalling of the southern upper low will occur as subtropical ridging builds across the western Atlantic and a tropical cyclone enters the eastern Gulf of Mexico. Latest forecast guidance from NHC for this tropical cyclone, which was recently upgraded to Tropical Storm Helene, suggests the storm will reach hurricane strength during the day Wednesday, with additional strengthening to major hurricane strength by early Thursday morning. Farther west, a progressive shortwave trough is forecast to move quickly across southern British Columbia and the Pacific Northwest, ending the period over the northern Rockies. At the surface, a weak front will likely extend from a low over the Lake Huron vicinity southward through middle TN before arcing more southwestward to another low in southeast TX. Western portion of this front over TX and LA is forecast to remain progressive, pushing southeastward to the western Gulf Coast by Wednesday evening. Eastern portion of the front will stall, maintaining a more north-south orientation from northern AL through southern Lower MI. ...Upper OH Valley through the southern Appalachians into AL, GA, and FL Panhandle Wednesday morning into the evening... A belt of enhanced southwesterly flow aloft is forecast to extend through the eastern periphery of the upper low developing over the Mid-South from the FL Panhandle northward into the Upper OH Valley. Widespread showers and thunderstorms are anticipated within this warm conveyor, reaching as far north as western A. However, poor lapse rates and limited destabilization should mitigate the overall severe potential across the majority of this region. An area of locally higher severe potential is anticipated within a spatially constrained corridor from southeast AL into far southwest GA and the western FL Panhandle, just west of the primary axis of precipitation anticipated within the warm conveyor. Here, a mix of low 70s dewpoints, modest heating, and moderate mid-level flow could result in a few thunderstorms capable of damaging gusts and/or a brief tornado or two. ...Much of the FL Peninsula... Rainbands associated with tropical cyclone Helene are forecast to move across the FL Peninsula throughout the period. At the same time, low to mid-level flow attendant to the cyclone will increase as the cyclone and its expansive wind field spread northward. As a result, vertical shear will be strong enough to support organized storm structure. Primary mitigating factor is warm, poor lapse rate profiles that limit buoyancy. Brief tornadoes will be possible within any updrafts that are able to mature/persist. ..Mosier.. 09/24/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 24 2024 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST ALABAMA INTO THE WESTERN FLORIDA PANHANDLE...AND ACROSS MUCH OF THE FLORIDA PENINSULA... ...SUMMARY... Isolated severe thunderstorms capable of damaging gusts and/or brief tornadoes are possible from southeast Alabama into the western Florida Panhandle, and across much of the Florida Peninsula. ...Synopsis... An amplified upper pattern, featuring a ridge extended from northern Mexico through the northern High Plains and a trough extended from Ontario into the Lower MS Valley, will cover the CONUS early Wednesday. Bifurcation of the upper trough is anticipated throughout the period, with a northern shortwave trough remaining progressive as it moves across eastern Ontario into southern Quebec, and a southern upper low stalling over the Mid-South vicinity. The stalling of the southern upper low will occur as subtropical ridging builds across the western Atlantic and a tropical cyclone enters the eastern Gulf of Mexico. Latest forecast guidance from NHC for this tropical cyclone, which was recently upgraded to Tropical Storm Helene, suggests the storm will reach hurricane strength during the day Wednesday, with additional strengthening to major hurricane strength by early Thursday morning. Farther west, a progressive shortwave trough is forecast to move quickly across southern British Columbia and the Pacific Northwest, ending the period over the northern Rockies. At the surface, a weak front will likely extend from a low over the Lake Huron vicinity southward through middle TN before arcing more southwestward to another low in southeast TX. Western portion of this front over TX and LA is forecast to remain progressive, pushing southeastward to the western Gulf Coast by Wednesday evening. Eastern portion of the front will stall, maintaining a more north-south orientation from northern AL through southern Lower MI. ...Upper OH Valley through the southern Appalachians into AL, GA, and FL Panhandle Wednesday morning into the evening... A belt of enhanced southwesterly flow aloft is forecast to extend through the eastern periphery of the upper low developing over the Mid-South from the FL Panhandle northward into the Upper OH Valley. Widespread showers and thunderstorms are anticipated within this warm conveyor, reaching as far north as western A. However, poor lapse rates and limited destabilization should mitigate the overall severe potential across the majority of this region. An area of locally higher severe potential is anticipated within a spatially constrained corridor from southeast AL into far southwest GA and the western FL Panhandle, just west of the primary axis of precipitation anticipated within the warm conveyor. Here, a mix of low 70s dewpoints, modest heating, and moderate mid-level flow could result in a few thunderstorms capable of damaging gusts and/or a brief tornado or two. ...Much of the FL Peninsula... Rainbands associated with tropical cyclone Helene are forecast to move across the FL Peninsula throughout the period. At the same time, low to mid-level flow attendant to the cyclone will increase as the cyclone and its expansive wind field spread northward. As a result, vertical shear will be strong enough to support organized storm structure. Primary mitigating factor is warm, poor lapse rate profiles that limit buoyancy. Brief tornadoes will be possible within any updrafts that are able to mature/persist. ..Mosier.. 09/24/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 24 2024 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST ALABAMA INTO THE WESTERN FLORIDA PANHANDLE...AND ACROSS MUCH OF THE FLORIDA PENINSULA... ...SUMMARY... Isolated severe thunderstorms capable of damaging gusts and/or brief tornadoes are possible from southeast Alabama into the western Florida Panhandle, and across much of the Florida Peninsula. ...Synopsis... An amplified upper pattern, featuring a ridge extended from northern Mexico through the northern High Plains and a trough extended from Ontario into the Lower MS Valley, will cover the CONUS early Wednesday. Bifurcation of the upper trough is anticipated throughout the period, with a northern shortwave trough remaining progressive as it moves across eastern Ontario into southern Quebec, and a southern upper low stalling over the Mid-South vicinity. The stalling of the southern upper low will occur as subtropical ridging builds across the western Atlantic and a tropical cyclone enters the eastern Gulf of Mexico. Latest forecast guidance from NHC for this tropical cyclone, which was recently upgraded to Tropical Storm Helene, suggests the storm will reach hurricane strength during the day Wednesday, with additional strengthening to major hurricane strength by early Thursday morning. Farther west, a progressive shortwave trough is forecast to move quickly across southern British Columbia and the Pacific Northwest, ending the period over the northern Rockies. At the surface, a weak front will likely extend from a low over the Lake Huron vicinity southward through middle TN before arcing more southwestward to another low in southeast TX. Western portion of this front over TX and LA is forecast to remain progressive, pushing southeastward to the western Gulf Coast by Wednesday evening. Eastern portion of the front will stall, maintaining a more north-south orientation from northern AL through southern Lower MI. ...Upper OH Valley through the southern Appalachians into AL, GA, and FL Panhandle Wednesday morning into the evening... A belt of enhanced southwesterly flow aloft is forecast to extend through the eastern periphery of the upper low developing over the Mid-South from the FL Panhandle northward into the Upper OH Valley. Widespread showers and thunderstorms are anticipated within this warm conveyor, reaching as far north as western A. However, poor lapse rates and limited destabilization should mitigate the overall severe potential across the majority of this region. An area of locally higher severe potential is anticipated within a spatially constrained corridor from southeast AL into far southwest GA and the western FL Panhandle, just west of the primary axis of precipitation anticipated within the warm conveyor. Here, a mix of low 70s dewpoints, modest heating, and moderate mid-level flow could result in a few thunderstorms capable of damaging gusts and/or a brief tornado or two. ...Much of the FL Peninsula... Rainbands associated with tropical cyclone Helene are forecast to move across the FL Peninsula throughout the period. At the same time, low to mid-level flow attendant to the cyclone will increase as the cyclone and its expansive wind field spread northward. As a result, vertical shear will be strong enough to support organized storm structure. Primary mitigating factor is warm, poor lapse rate profiles that limit buoyancy. Brief tornadoes will be possible within any updrafts that are able to mature/persist. ..Mosier.. 09/24/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 24 2024 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST ALABAMA INTO THE WESTERN FLORIDA PANHANDLE...AND ACROSS MUCH OF THE FLORIDA PENINSULA... ...SUMMARY... Isolated severe thunderstorms capable of damaging gusts and/or brief tornadoes are possible from southeast Alabama into the western Florida Panhandle, and across much of the Florida Peninsula. ...Synopsis... An amplified upper pattern, featuring a ridge extended from northern Mexico through the northern High Plains and a trough extended from Ontario into the Lower MS Valley, will cover the CONUS early Wednesday. Bifurcation of the upper trough is anticipated throughout the period, with a northern shortwave trough remaining progressive as it moves across eastern Ontario into southern Quebec, and a southern upper low stalling over the Mid-South vicinity. The stalling of the southern upper low will occur as subtropical ridging builds across the western Atlantic and a tropical cyclone enters the eastern Gulf of Mexico. Latest forecast guidance from NHC for this tropical cyclone, which was recently upgraded to Tropical Storm Helene, suggests the storm will reach hurricane strength during the day Wednesday, with additional strengthening to major hurricane strength by early Thursday morning. Farther west, a progressive shortwave trough is forecast to move quickly across southern British Columbia and the Pacific Northwest, ending the period over the northern Rockies. At the surface, a weak front will likely extend from a low over the Lake Huron vicinity southward through middle TN before arcing more southwestward to another low in southeast TX. Western portion of this front over TX and LA is forecast to remain progressive, pushing southeastward to the western Gulf Coast by Wednesday evening. Eastern portion of the front will stall, maintaining a more north-south orientation from northern AL through southern Lower MI. ...Upper OH Valley through the southern Appalachians into AL, GA, and FL Panhandle Wednesday morning into the evening... A belt of enhanced southwesterly flow aloft is forecast to extend through the eastern periphery of the upper low developing over the Mid-South from the FL Panhandle northward into the Upper OH Valley. Widespread showers and thunderstorms are anticipated within this warm conveyor, reaching as far north as western A. However, poor lapse rates and limited destabilization should mitigate the overall severe potential across the majority of this region. An area of locally higher severe potential is anticipated within a spatially constrained corridor from southeast AL into far southwest GA and the western FL Panhandle, just west of the primary axis of precipitation anticipated within the warm conveyor. Here, a mix of low 70s dewpoints, modest heating, and moderate mid-level flow could result in a few thunderstorms capable of damaging gusts and/or a brief tornado or two. ...Much of the FL Peninsula... Rainbands associated with tropical cyclone Helene are forecast to move across the FL Peninsula throughout the period. At the same time, low to mid-level flow attendant to the cyclone will increase as the cyclone and its expansive wind field spread northward. As a result, vertical shear will be strong enough to support organized storm structure. Primary mitigating factor is warm, poor lapse rate profiles that limit buoyancy. Brief tornadoes will be possible within any updrafts that are able to mature/persist. ..Mosier.. 09/24/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 24 2024 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST ALABAMA INTO THE WESTERN FLORIDA PANHANDLE...AND ACROSS MUCH OF THE FLORIDA PENINSULA... ...SUMMARY... Isolated severe thunderstorms capable of damaging gusts and/or brief tornadoes are possible from southeast Alabama into the western Florida Panhandle, and across much of the Florida Peninsula. ...Synopsis... An amplified upper pattern, featuring a ridge extended from northern Mexico through the northern High Plains and a trough extended from Ontario into the Lower MS Valley, will cover the CONUS early Wednesday. Bifurcation of the upper trough is anticipated throughout the period, with a northern shortwave trough remaining progressive as it moves across eastern Ontario into southern Quebec, and a southern upper low stalling over the Mid-South vicinity. The stalling of the southern upper low will occur as subtropical ridging builds across the western Atlantic and a tropical cyclone enters the eastern Gulf of Mexico. Latest forecast guidance from NHC for this tropical cyclone, which was recently upgraded to Tropical Storm Helene, suggests the storm will reach hurricane strength during the day Wednesday, with additional strengthening to major hurricane strength by early Thursday morning. Farther west, a progressive shortwave trough is forecast to move quickly across southern British Columbia and the Pacific Northwest, ending the period over the northern Rockies. At the surface, a weak front will likely extend from a low over the Lake Huron vicinity southward through middle TN before arcing more southwestward to another low in southeast TX. Western portion of this front over TX and LA is forecast to remain progressive, pushing southeastward to the western Gulf Coast by Wednesday evening. Eastern portion of the front will stall, maintaining a more north-south orientation from northern AL through southern Lower MI. ...Upper OH Valley through the southern Appalachians into AL, GA, and FL Panhandle Wednesday morning into the evening... A belt of enhanced southwesterly flow aloft is forecast to extend through the eastern periphery of the upper low developing over the Mid-South from the FL Panhandle northward into the Upper OH Valley. Widespread showers and thunderstorms are anticipated within this warm conveyor, reaching as far north as western A. However, poor lapse rates and limited destabilization should mitigate the overall severe potential across the majority of this region. An area of locally higher severe potential is anticipated within a spatially constrained corridor from southeast AL into far southwest GA and the western FL Panhandle, just west of the primary axis of precipitation anticipated within the warm conveyor. Here, a mix of low 70s dewpoints, modest heating, and moderate mid-level flow could result in a few thunderstorms capable of damaging gusts and/or a brief tornado or two. ...Much of the FL Peninsula... Rainbands associated with tropical cyclone Helene are forecast to move across the FL Peninsula throughout the period. At the same time, low to mid-level flow attendant to the cyclone will increase as the cyclone and its expansive wind field spread northward. As a result, vertical shear will be strong enough to support organized storm structure. Primary mitigating factor is warm, poor lapse rate profiles that limit buoyancy. Brief tornadoes will be possible within any updrafts that are able to mature/persist. ..Mosier.. 09/24/2024 Read more