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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Tue Sep 24 2024 Valid 241630Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF TN/KY/OH/WV AND CENTRAL OK... ...SUMMARY... Isolated to scattered severe thunderstorms are possible mainly this afternoon across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. Severe storms will also be possible across portions of Oklahoma. ...Ohio and Tennessee Valleys to southern Appalachians... Have spatially adjusted/expanded the Slight Risk based on observational trends and somewhat stronger destabilization across areas such as northern/middle Tennessee. Water-vapor imagery shows a mid-level vorticity maximum moving across the middle Mississippi Valley and into the Ohio Valley. A belt of moderate to strong southwesterly 500-mb flow (25-50 kt) will overspread Kentucky and the surrounding states. A surface low will migrate east-northeast into southern Lower Michigan by early evening, where isolated severe storms are possible, with a frontal zone extending south-southwest from this low into the Mid South. In the wake of early morning convection, modest cloud breaks/destabilization is forecast with upwards of 750-2000 J/kg MLCAPE from the southern Great Lakes into the southern Appalachians, with the strongest destabilization expected across Tennessee into southern Kentucky and possibly the western Carolinas pending the timing/abatement of lingering cloud cover. Regionally, ample deep-layer speed shear will aid in storm organization into organized multicells and probably several supercells. Damaging winds will be the most common hazard, but isolated large hail will be possible, and some tornado risk may exist as well. ...Oklahoma/North Texas... Have upgraded portions of central Oklahoma for what is expected to be a semi-focused regional corridor of large hail potential late this afternoon and early evening. The region will be influenced by the immediate backside of a southeastward-moving upper-level trough centered over the Lower Missouri Valley. A considerably strengthening cyclonically curved belt of westerlies aloft will influence Oklahoma, overspreading a relatively moist air mass, with lower to some middle 60s F surface dewpoints likely to persist through the diurnal heating/mixing cycle. Near a deepening surface low and nearby triple point/warm front, at least isolated storms are expected to develop as early as mid-afternoon (3-4pm), becoming more probable with a greater coverage through sunset. Overall buoyancy will not be robust, with MLCAPE generally not expected to exceed 1000 J/kg later this afternoon. However, this buoyancy, along with steep lapse rates and robustly vertically veering wind profiles, accentuated by 35-45 kt northwesterly mid/upper-level flow, should support initial supercells capable of large hail (potentially golfball size), along with some potential for damaging wind gusts. These storms will persist generally southeastward through the evening into southern/southeast Oklahoma, and probably north Texas overnight. Overall intensity will tend to wane nocturnally after sunset, but some severe hail/wind potential will probably linger, particularly on the west/southwest flank of any evolving clusters of storms, which will be increasingly elevated to the east of the warm front. ..Guyer/Lyons.. 09/24/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Tue Sep 24 2024 Valid 241630Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF TN/KY/OH/WV AND CENTRAL OK... ...SUMMARY... Isolated to scattered severe thunderstorms are possible mainly this afternoon across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. Severe storms will also be possible across portions of Oklahoma. ...Ohio and Tennessee Valleys to southern Appalachians... Have spatially adjusted/expanded the Slight Risk based on observational trends and somewhat stronger destabilization across areas such as northern/middle Tennessee. Water-vapor imagery shows a mid-level vorticity maximum moving across the middle Mississippi Valley and into the Ohio Valley. A belt of moderate to strong southwesterly 500-mb flow (25-50 kt) will overspread Kentucky and the surrounding states. A surface low will migrate east-northeast into southern Lower Michigan by early evening, where isolated severe storms are possible, with a frontal zone extending south-southwest from this low into the Mid South. In the wake of early morning convection, modest cloud breaks/destabilization is forecast with upwards of 750-2000 J/kg MLCAPE from the southern Great Lakes into the southern Appalachians, with the strongest destabilization expected across Tennessee into southern Kentucky and possibly the western Carolinas pending the timing/abatement of lingering cloud cover. Regionally, ample deep-layer speed shear will aid in storm organization into organized multicells and probably several supercells. Damaging winds will be the most common hazard, but isolated large hail will be possible, and some tornado risk may exist as well. ...Oklahoma/North Texas... Have upgraded portions of central Oklahoma for what is expected to be a semi-focused regional corridor of large hail potential late this afternoon and early evening. The region will be influenced by the immediate backside of a southeastward-moving upper-level trough centered over the Lower Missouri Valley. A considerably strengthening cyclonically curved belt of westerlies aloft will influence Oklahoma, overspreading a relatively moist air mass, with lower to some middle 60s F surface dewpoints likely to persist through the diurnal heating/mixing cycle. Near a deepening surface low and nearby triple point/warm front, at least isolated storms are expected to develop as early as mid-afternoon (3-4pm), becoming more probable with a greater coverage through sunset. Overall buoyancy will not be robust, with MLCAPE generally not expected to exceed 1000 J/kg later this afternoon. However, this buoyancy, along with steep lapse rates and robustly vertically veering wind profiles, accentuated by 35-45 kt northwesterly mid/upper-level flow, should support initial supercells capable of large hail (potentially golfball size), along with some potential for damaging wind gusts. These storms will persist generally southeastward through the evening into southern/southeast Oklahoma, and probably north Texas overnight. Overall intensity will tend to wane nocturnally after sunset, but some severe hail/wind potential will probably linger, particularly on the west/southwest flank of any evolving clusters of storms, which will be increasingly elevated to the east of the warm front. ..Guyer/Lyons.. 09/24/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Tue Sep 24 2024 Valid 241630Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF TN/KY/OH/WV AND CENTRAL OK... ...SUMMARY... Isolated to scattered severe thunderstorms are possible mainly this afternoon across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. Severe storms will also be possible across portions of Oklahoma. ...Ohio and Tennessee Valleys to southern Appalachians... Have spatially adjusted/expanded the Slight Risk based on observational trends and somewhat stronger destabilization across areas such as northern/middle Tennessee. Water-vapor imagery shows a mid-level vorticity maximum moving across the middle Mississippi Valley and into the Ohio Valley. A belt of moderate to strong southwesterly 500-mb flow (25-50 kt) will overspread Kentucky and the surrounding states. A surface low will migrate east-northeast into southern Lower Michigan by early evening, where isolated severe storms are possible, with a frontal zone extending south-southwest from this low into the Mid South. In the wake of early morning convection, modest cloud breaks/destabilization is forecast with upwards of 750-2000 J/kg MLCAPE from the southern Great Lakes into the southern Appalachians, with the strongest destabilization expected across Tennessee into southern Kentucky and possibly the western Carolinas pending the timing/abatement of lingering cloud cover. Regionally, ample deep-layer speed shear will aid in storm organization into organized multicells and probably several supercells. Damaging winds will be the most common hazard, but isolated large hail will be possible, and some tornado risk may exist as well. ...Oklahoma/North Texas... Have upgraded portions of central Oklahoma for what is expected to be a semi-focused regional corridor of large hail potential late this afternoon and early evening. The region will be influenced by the immediate backside of a southeastward-moving upper-level trough centered over the Lower Missouri Valley. A considerably strengthening cyclonically curved belt of westerlies aloft will influence Oklahoma, overspreading a relatively moist air mass, with lower to some middle 60s F surface dewpoints likely to persist through the diurnal heating/mixing cycle. Near a deepening surface low and nearby triple point/warm front, at least isolated storms are expected to develop as early as mid-afternoon (3-4pm), becoming more probable with a greater coverage through sunset. Overall buoyancy will not be robust, with MLCAPE generally not expected to exceed 1000 J/kg later this afternoon. However, this buoyancy, along with steep lapse rates and robustly vertically veering wind profiles, accentuated by 35-45 kt northwesterly mid/upper-level flow, should support initial supercells capable of large hail (potentially golfball size), along with some potential for damaging wind gusts. These storms will persist generally southeastward through the evening into southern/southeast Oklahoma, and probably north Texas overnight. Overall intensity will tend to wane nocturnally after sunset, but some severe hail/wind potential will probably linger, particularly on the west/southwest flank of any evolving clusters of storms, which will be increasingly elevated to the east of the warm front. ..Guyer/Lyons.. 09/24/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Tue Sep 24 2024 Valid 241630Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF TN/KY/OH/WV AND CENTRAL OK... ...SUMMARY... Isolated to scattered severe thunderstorms are possible mainly this afternoon across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. Severe storms will also be possible across portions of Oklahoma. ...Ohio and Tennessee Valleys to southern Appalachians... Have spatially adjusted/expanded the Slight Risk based on observational trends and somewhat stronger destabilization across areas such as northern/middle Tennessee. Water-vapor imagery shows a mid-level vorticity maximum moving across the middle Mississippi Valley and into the Ohio Valley. A belt of moderate to strong southwesterly 500-mb flow (25-50 kt) will overspread Kentucky and the surrounding states. A surface low will migrate east-northeast into southern Lower Michigan by early evening, where isolated severe storms are possible, with a frontal zone extending south-southwest from this low into the Mid South. In the wake of early morning convection, modest cloud breaks/destabilization is forecast with upwards of 750-2000 J/kg MLCAPE from the southern Great Lakes into the southern Appalachians, with the strongest destabilization expected across Tennessee into southern Kentucky and possibly the western Carolinas pending the timing/abatement of lingering cloud cover. Regionally, ample deep-layer speed shear will aid in storm organization into organized multicells and probably several supercells. Damaging winds will be the most common hazard, but isolated large hail will be possible, and some tornado risk may exist as well. ...Oklahoma/North Texas... Have upgraded portions of central Oklahoma for what is expected to be a semi-focused regional corridor of large hail potential late this afternoon and early evening. The region will be influenced by the immediate backside of a southeastward-moving upper-level trough centered over the Lower Missouri Valley. A considerably strengthening cyclonically curved belt of westerlies aloft will influence Oklahoma, overspreading a relatively moist air mass, with lower to some middle 60s F surface dewpoints likely to persist through the diurnal heating/mixing cycle. Near a deepening surface low and nearby triple point/warm front, at least isolated storms are expected to develop as early as mid-afternoon (3-4pm), becoming more probable with a greater coverage through sunset. Overall buoyancy will not be robust, with MLCAPE generally not expected to exceed 1000 J/kg later this afternoon. However, this buoyancy, along with steep lapse rates and robustly vertically veering wind profiles, accentuated by 35-45 kt northwesterly mid/upper-level flow, should support initial supercells capable of large hail (potentially golfball size), along with some potential for damaging wind gusts. These storms will persist generally southeastward through the evening into southern/southeast Oklahoma, and probably north Texas overnight. Overall intensity will tend to wane nocturnally after sunset, but some severe hail/wind potential will probably linger, particularly on the west/southwest flank of any evolving clusters of storms, which will be increasingly elevated to the east of the warm front. ..Guyer/Lyons.. 09/24/2024 Read more

Drought has killed trees, shrubs and other plants in Chattanooga due to insufficient water. Trees are turning color early in northeast Tennessee. Chattanooga Times Free Press (Tenn.), Sept 22, 2024

Issued at 900 AM CST Tue Sep 24 2024 628 WTPZ45 KNHC 241435 TCDEP5 Tropical Storm John Discussion Number 9 NWS National Hurricane Center Miami FL EP102024 900 AM CST Tue Sep 24 2024 John has been rapidly weakening since it moved inland last night, and the maximum sustained winds are now estimated to be around 35 kt. The storm still has a well-defined mid-level center, but surface observations suggest that the low-level circulation is less defined and could be opening into a trough. A strong band of thunderstorms to the east of the estimated center continues to produce heavy rains across portions of southern Mexico. There is quite a bit of uncertainty in the future of John. One possibility is that the storm dissipates over Mexico, with a trough or low reforming back offshore and lingering in that location for much of the rest of the week. The other possibility is that John itself hangs on as a tropical depression or storm. For now, the official forecast generally follows the previous scenario and shows John weakening to a tropical depression later today and lingering near the coast of southern and southwestern Mexico until the end of the week. It is hoped that additional data and model runs later today will help provide some clarity on the system's future. Even though the future of John is uncertain, there is high confidence that heavy rains will continue in portions of southern and southwestern Mexico during the next couple of days. See the Key Messages below for additional information on that hazard. KEY MESSAGES: 1. Slow-moving John will continue to bring very heavy rainfall to coastal portions of southern and southwestern Mexico through the upcoming week. This heavy rainfall will likely cause significant and possibly catastrophic, life-threatening flash flooding and mudslides to the Mexican States of Chiapas, Oaxaca, and southeast Guerrero, particularly in areas near the coast and along the up-slope portion of areas of higher terrain. 2. John could still produce tropical storm conditions for the next couple of hours in the tropical storm warning area. FORECAST POSITIONS AND MAX WINDS INIT 24/1500Z 17.7N 100.5W 35 KT 40 MPH...INLAND 12H 25/0000Z 17.7N 101.1W 30 KT 35 MPH...INLAND 24H 25/1200Z 17.3N 101.1W 30 KT 35 MPH...OVER WATER 36H 26/0000Z 17.1N 100.8W 30 KT 35 MPH 48H 26/1200Z 17.4N 100.7W 25 KT 30 MPH...INLAND 60H 27/0000Z 17.7N 100.8W 25 KT 30 MPH...INLAND 72H 27/1200Z...DISSIPATED $$ Forecaster Cangialosi

5-Day Uncertainty Track last updated Tue, 24 Sep 2024 15:05:13 GMT


Wind Speed Probabilities last updated Tue, 24 Sep 2024 15:28:54 GMT

...LIFE-THREATENING FLASH FLOODING POSSIBLE ACROSS PORTIONS OF SOUTHERN AND SOUTHWESTERN MEXICO DURING THE NEXT FEW DAYS... As of 9:00 AM CST Tue Sep 24 the center of John was located near 17.7, -100.5 with movement NW at 12 mph. The minimum central pressure was 1001 mb with maximum sustained winds of about 40 mph.

Issued at 1500 UTC TUE SEP 24 2024 223 FOPZ15 KNHC 241434 PWSEP5 TROPICAL STORM JOHN WIND SPEED PROBABILITIES NUMBER 9 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102024 1500 UTC TUE SEP 24 2024 AT 1500Z THE CENTER OF TROPICAL STORM JOHN WAS LOCATED NEAR LATITUDE 17.7 NORTH...LONGITUDE 100.5 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 35 KTS...40 MPH...65 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 L CARDENAS 34 1 1( 2) 1( 3) X( 3) 1( 4) X( 4) X( 4) ZIHUATANEJO 34 11 2(13) 2(15) X(15) 1(16) X(16) X(16) ACAPULCO 34 1 X( 1) 2( 3) 3( 6) 1( 7) X( 7) X( 7) $$ FORECASTER CANGIALOSI

Issued at 900 AM CST Tue Sep 24 2024 222 WTPZ35 KNHC 241434 TCPEP5 BULLETIN Tropical Storm John Advisory Number 9 NWS National Hurricane Center Miami FL EP102024 900 AM CST Tue Sep 24 2024 ...LIFE-THREATENING FLASH FLOODING POSSIBLE ACROSS PORTIONS OF SOUTHERN AND SOUTHWESTERN MEXICO DURING THE NEXT FEW DAYS... SUMMARY OF 900 AM CST...1500 UTC...INFORMATION ---------------------------------------------- LOCATION...17.7N 100.5W ABOUT 70 MI...110 KM NW OF ACAPULCO MEXICO MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...NW OR 310 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...1001 MB...29.56 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Warning is in effect for... * Punta Maldonado to Zihuatanejo A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area, in this case over the next few hours. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 900 AM CST (1500 UTC), the center of Tropical Storm John was located near latitude 17.7 North, longitude 100.5 West. John is moving toward the northwest near 12 mph (19 km/h). Little motion is expected during the next few days. Maximum sustained winds are near 40 mph (65 km/h) with higher gusts. Slow weakening is expected during the next couple of days. Tropical-storm-force winds extend outward up to 80 miles (130 km) from the center. The estimated minimum central pressure is 1001 mb (29.56 inches). HAZARDS AFFECTING LAND ---------------------- Key Messages for John can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDEP5 and WMO header WTPZ45 KNHC and on the web at hurricanes.gov/text/MIATCDEP5.shtml RAINFALL: Through Thursday, Tropical Storm John is 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. For a complete depiction of forecast rainfall associated with Tropical Storm John, please see the National Weather Service Storm Total Rainfall Graphic, available at hurricanes.gov/graphics_ep5.shtml?rainqpf WIND: Tropical storm conditions are ongoing within portions of the tropical storm warning area and should continue for the next couple of hours. Wind speeds atop and on the windward sides of hills and mountains are often up to 30 percent stronger than the near-surface winds indicated in this advisory, and in some elevated locations could be even greater. SURF: Swells associated with John are forecast to continue affecting the coast of southern Mexico during the next day or so, with the potential for dangerous surf and rip currents. Please see local statements for more information. NEXT ADVISORY ------------- Next intermediate advisory at 1200 PM CST. Next complete advisory at 300 PM CST. $$ Forecaster Cangialosi

Issued at 1500 UTC TUE SEP 24 2024 085 WTPZ25 KNHC 241434 TCMEP5 TROPICAL STORM JOHN FORECAST/ADVISORY NUMBER 9 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102024 1500 UTC TUE SEP 24 2024 TROPICAL STORM CENTER LOCATED NEAR 17.7N 100.5W AT 24/1500Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE NORTHWEST OR 310 DEGREES AT 10 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1001 MB MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT. 34 KT....... 0NE 70SE 70SW 0NW. 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 100.5W AT 24/1500Z AT 24/1200Z CENTER WAS LOCATED NEAR 17.7N 100.3W FORECAST VALID 25/0000Z 17.7N 101.1W...INLAND MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 25/1200Z 17.3N 101.1W...OVER WATER MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 26/0000Z 17.1N 100.8W MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 26/1200Z 17.4N 100.7W...INLAND MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 27/0000Z 17.7N 100.8W...INLAND MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 27/1200Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 17.7N 100.5W INTERMEDIATE PUBLIC ADVISORY...WTNT35 KNHC/MIATCPEP5...AT 24/1800Z NEXT ADVISORY AT 24/2100Z $$ FORECASTER CANGIALOSI

5-Day Uncertainty Track last updated Tue, 24 Sep 2024 14:36:52 GMT


Wind Speed Probabilities last updated Tue, 24 Sep 2024 14:36:52 GMT

...LIFE-THREATENING FLASH FLOODING POSSIBLE ACROSS PORTIONS OF SOUTHERN AND SOUTHWESTERN MEXICO DURING THE NEXT FEW DAYS... As of 9:00 AM CST Tue Sep 24 the center of John was located near 17.7, -100.5 with movement NW at 12 mph. The minimum central pressure was 1001 mb with maximum sustained winds of about 40 mph.

Pumpkins growers in southwest Ohio grew plenty of pumpkins, but they are smaller, due to drought. The pumpkins hold less water this year, so they will weigh less and cost less. WXIX-TV FOX 19 Cincinnati (Ohio), Sept 20, 2024

At least 11 West Virginia counties have issued burn bans, due to the drought and heightened fire danger. The sheriff’s office relies on citizens to notice violators and report fires. Fines can range from $100 to $1,200. WCHS-TV ABC 8 (Charleston, W.V.),Sept 24, 2024

No Mesoscale Discussions are in effect as of Tue Sep 24 12:54:02 UTC 2024.

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Tue Sep 24 2024 Valid 241300Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL KENTUCKY INTO SOUTHERN OHIO AND WEST VIRGINIA... ...SUMMARY... Isolated to scattered severe thunderstorms are possible mainly this afternoon across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. A few strong/severe storms are also possible across portions of the southern Plains. ...Ohio and Tennessee Valleys to southern Appalachians... Water-vapor imagery this morning shows a mid-level vorticity maximum moving across the middle MS Valley and into the OH Valley. A belt of moderate to strong southwesterly 500-mb flow (25-50 kt) will overspread KY and the surrounding states, with the strongest flow generally within the Slight Risk bounds. Bands of showers/weak thunderstorms are ongoing this morning from middle TN into OH, and in a separate area over eastern IL immediately ahead of the surface low. This low will migrate east-northeast into southern Lower MI by early evening with a frontal zone extending south-southwest into the Mid South. In wake of the early morning convection, some cloud breaks/destabilization is forecast with upwards of 750-2000 J/kg MLCAPE from the southern Great Lakes into the southern Appalachian states. Ample deep-layer speed shear (via mostly southwesterly flow through the troposphere) will aid in storm organization into organized multicells and probably several supercells. Only notable change this outlook update was to include portions of the southern Great Lakes in low-severe probabilities for potential activity near/ahead of the surface low. The primary concern across the general region will likely be damaging winds with the stronger storms. ...OK vicinity... An amplifying large-scale trough over the MS Valley will feature a 60-kt 500mb speed max moving southward into the central Great Plains by early evening on the backside of the upper trough. Left exit region of this feature will encourage large-scale ascent, and a weak surface wave/low should evolve over southwest KS/northwest OK by early afternoon. Strong heating will contribute to 750-1250 J/kg MLCAPE by mid afternoon across OK with flow veering and strengthening with height. Elongated hodographs will support the potential for hail growth with a few of the stronger/sustained updrafts that evolve. An isolated threat for large hail (1 to 1.75 inches in diameter) and/or severe gusts (60-70 mph) will probably peak during the 23z-03z period before storms weaken during the late evening. ..Smith/Broyles.. 09/24/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Tue Sep 24 2024 Valid 241300Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL KENTUCKY INTO SOUTHERN OHIO AND WEST VIRGINIA... ...SUMMARY... Isolated to scattered severe thunderstorms are possible mainly this afternoon across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. A few strong/severe storms are also possible across portions of the southern Plains. ...Ohio and Tennessee Valleys to southern Appalachians... Water-vapor imagery this morning shows a mid-level vorticity maximum moving across the middle MS Valley and into the OH Valley. A belt of moderate to strong southwesterly 500-mb flow (25-50 kt) will overspread KY and the surrounding states, with the strongest flow generally within the Slight Risk bounds. Bands of showers/weak thunderstorms are ongoing this morning from middle TN into OH, and in a separate area over eastern IL immediately ahead of the surface low. This low will migrate east-northeast into southern Lower MI by early evening with a frontal zone extending south-southwest into the Mid South. In wake of the early morning convection, some cloud breaks/destabilization is forecast with upwards of 750-2000 J/kg MLCAPE from the southern Great Lakes into the southern Appalachian states. Ample deep-layer speed shear (via mostly southwesterly flow through the troposphere) will aid in storm organization into organized multicells and probably several supercells. Only notable change this outlook update was to include portions of the southern Great Lakes in low-severe probabilities for potential activity near/ahead of the surface low. The primary concern across the general region will likely be damaging winds with the stronger storms. ...OK vicinity... An amplifying large-scale trough over the MS Valley will feature a 60-kt 500mb speed max moving southward into the central Great Plains by early evening on the backside of the upper trough. Left exit region of this feature will encourage large-scale ascent, and a weak surface wave/low should evolve over southwest KS/northwest OK by early afternoon. Strong heating will contribute to 750-1250 J/kg MLCAPE by mid afternoon across OK with flow veering and strengthening with height. Elongated hodographs will support the potential for hail growth with a few of the stronger/sustained updrafts that evolve. An isolated threat for large hail (1 to 1.75 inches in diameter) and/or severe gusts (60-70 mph) will probably peak during the 23z-03z period before storms weaken during the late evening. ..Smith/Broyles.. 09/24/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Tue Sep 24 2024 Valid 241300Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL KENTUCKY INTO SOUTHERN OHIO AND WEST VIRGINIA... ...SUMMARY... Isolated to scattered severe thunderstorms are possible mainly this afternoon across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. A few strong/severe storms are also possible across portions of the southern Plains. ...Ohio and Tennessee Valleys to southern Appalachians... Water-vapor imagery this morning shows a mid-level vorticity maximum moving across the middle MS Valley and into the OH Valley. A belt of moderate to strong southwesterly 500-mb flow (25-50 kt) will overspread KY and the surrounding states, with the strongest flow generally within the Slight Risk bounds. Bands of showers/weak thunderstorms are ongoing this morning from middle TN into OH, and in a separate area over eastern IL immediately ahead of the surface low. This low will migrate east-northeast into southern Lower MI by early evening with a frontal zone extending south-southwest into the Mid South. In wake of the early morning convection, some cloud breaks/destabilization is forecast with upwards of 750-2000 J/kg MLCAPE from the southern Great Lakes into the southern Appalachian states. Ample deep-layer speed shear (via mostly southwesterly flow through the troposphere) will aid in storm organization into organized multicells and probably several supercells. Only notable change this outlook update was to include portions of the southern Great Lakes in low-severe probabilities for potential activity near/ahead of the surface low. The primary concern across the general region will likely be damaging winds with the stronger storms. ...OK vicinity... An amplifying large-scale trough over the MS Valley will feature a 60-kt 500mb speed max moving southward into the central Great Plains by early evening on the backside of the upper trough. Left exit region of this feature will encourage large-scale ascent, and a weak surface wave/low should evolve over southwest KS/northwest OK by early afternoon. Strong heating will contribute to 750-1250 J/kg MLCAPE by mid afternoon across OK with flow veering and strengthening with height. Elongated hodographs will support the potential for hail growth with a few of the stronger/sustained updrafts that evolve. An isolated threat for large hail (1 to 1.75 inches in diameter) and/or severe gusts (60-70 mph) will probably peak during the 23z-03z period before storms weaken during the late evening. ..Smith/Broyles.. 09/24/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Tue Sep 24 2024 Valid 241300Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL KENTUCKY INTO SOUTHERN OHIO AND WEST VIRGINIA... ...SUMMARY... Isolated to scattered severe thunderstorms are possible mainly this afternoon across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. A few strong/severe storms are also possible across portions of the southern Plains. ...Ohio and Tennessee Valleys to southern Appalachians... Water-vapor imagery this morning shows a mid-level vorticity maximum moving across the middle MS Valley and into the OH Valley. A belt of moderate to strong southwesterly 500-mb flow (25-50 kt) will overspread KY and the surrounding states, with the strongest flow generally within the Slight Risk bounds. Bands of showers/weak thunderstorms are ongoing this morning from middle TN into OH, and in a separate area over eastern IL immediately ahead of the surface low. This low will migrate east-northeast into southern Lower MI by early evening with a frontal zone extending south-southwest into the Mid South. In wake of the early morning convection, some cloud breaks/destabilization is forecast with upwards of 750-2000 J/kg MLCAPE from the southern Great Lakes into the southern Appalachian states. Ample deep-layer speed shear (via mostly southwesterly flow through the troposphere) will aid in storm organization into organized multicells and probably several supercells. Only notable change this outlook update was to include portions of the southern Great Lakes in low-severe probabilities for potential activity near/ahead of the surface low. The primary concern across the general region will likely be damaging winds with the stronger storms. ...OK vicinity... An amplifying large-scale trough over the MS Valley will feature a 60-kt 500mb speed max moving southward into the central Great Plains by early evening on the backside of the upper trough. Left exit region of this feature will encourage large-scale ascent, and a weak surface wave/low should evolve over southwest KS/northwest OK by early afternoon. Strong heating will contribute to 750-1250 J/kg MLCAPE by mid afternoon across OK with flow veering and strengthening with height. Elongated hodographs will support the potential for hail growth with a few of the stronger/sustained updrafts that evolve. An isolated threat for large hail (1 to 1.75 inches in diameter) and/or severe gusts (60-70 mph) will probably peak during the 23z-03z period before storms weaken during the late evening. ..Smith/Broyles.. 09/24/2024 Read more