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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue May 20 2025 Valid 201300Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID/DEEP SOUTH TO TN VALLEY AND CUMBERLAND PLATEAU... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...Mid/Deep South to the TN/Lower OH Valleys and Cumberland Plateau... Water-vapor imagery this morning shows a negatively tilted, large-scale mid to upper-level trough centered over the Dakotas southeastward through the mid MS Valley and Ozarks. Several thunderstorms clusters are ongoing within a larger corridor of convection from the OH Valley southwestward into the lower MS Valley. This activity is occurring to the east/southeast of a gradually filling cyclone forecast to move from the lower MO Valley eastward into the southwest Great Lakes by late tonight. Little change was made to the previous outlook due in part to general consistency in model guidance and observational trends noted this morning. Richer low-level moisture from west-central KY southward into the Gulf Coast states will contribute to a moderate to very unstable airmass by the early afternoon in areas void of recent convective outflow and associated cloud debris. Scattered to numerous thunderstorms are forecast to develop coincident with the diurnal heating cycle. Forecast hodographs coupled with progged buoyancy will support a mix of supercells and line segments this afternoon. The initial supercell activity will potentially yield a threat for large to very large hail. It appears the greatest risk for supercell tornadoes may exist from northern MS east-northeastward into middle TN. Morning convection and associated destabilization concerns preclude higher tornado risk probabilities. However, models continue to indicate upscale growth into several bands will occur late this afternoon through the late evening as storms move east across the Enhanced (level 3) Risk area. Have enlarged severe/damaging wind probabilities across AL/GA to account for confidence in a continuation of a wind threat persisting through the evening. ...IL/IN... Within the left-exit region of a cyclonically curved mid to upper speed max, a dry slot and attendant corridor of steep lapse rates will likely evolve across portions of MO to IL/IN from midday into the afternoon. Destabilization will likely be less across the mid MS Valley eastward into IN, with the richer moisture confined south of residual outflow and warm frontal zone over the lower OH Valley. Nonetheless, isolated to scattered severe thunderstorms are possible later today into the evening via a mix of shorter-lived supercells and organized multicells. Isolated to scattered coverage of severe and all hazards are possible with the stronger storms before this activity diminishes during the evening. ..Smith/Marsh.. 05/20/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue May 20 2025 Valid 201300Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID/DEEP SOUTH TO TN VALLEY AND CUMBERLAND PLATEAU... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...Mid/Deep South to the TN/Lower OH Valleys and Cumberland Plateau... Water-vapor imagery this morning shows a negatively tilted, large-scale mid to upper-level trough centered over the Dakotas southeastward through the mid MS Valley and Ozarks. Several thunderstorms clusters are ongoing within a larger corridor of convection from the OH Valley southwestward into the lower MS Valley. This activity is occurring to the east/southeast of a gradually filling cyclone forecast to move from the lower MO Valley eastward into the southwest Great Lakes by late tonight. Little change was made to the previous outlook due in part to general consistency in model guidance and observational trends noted this morning. Richer low-level moisture from west-central KY southward into the Gulf Coast states will contribute to a moderate to very unstable airmass by the early afternoon in areas void of recent convective outflow and associated cloud debris. Scattered to numerous thunderstorms are forecast to develop coincident with the diurnal heating cycle. Forecast hodographs coupled with progged buoyancy will support a mix of supercells and line segments this afternoon. The initial supercell activity will potentially yield a threat for large to very large hail. It appears the greatest risk for supercell tornadoes may exist from northern MS east-northeastward into middle TN. Morning convection and associated destabilization concerns preclude higher tornado risk probabilities. However, models continue to indicate upscale growth into several bands will occur late this afternoon through the late evening as storms move east across the Enhanced (level 3) Risk area. Have enlarged severe/damaging wind probabilities across AL/GA to account for confidence in a continuation of a wind threat persisting through the evening. ...IL/IN... Within the left-exit region of a cyclonically curved mid to upper speed max, a dry slot and attendant corridor of steep lapse rates will likely evolve across portions of MO to IL/IN from midday into the afternoon. Destabilization will likely be less across the mid MS Valley eastward into IN, with the richer moisture confined south of residual outflow and warm frontal zone over the lower OH Valley. Nonetheless, isolated to scattered severe thunderstorms are possible later today into the evening via a mix of shorter-lived supercells and organized multicells. Isolated to scattered coverage of severe and all hazards are possible with the stronger storms before this activity diminishes during the evening. ..Smith/Marsh.. 05/20/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue May 20 2025 Valid 201300Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID/DEEP SOUTH TO TN VALLEY AND CUMBERLAND PLATEAU... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...Mid/Deep South to the TN/Lower OH Valleys and Cumberland Plateau... Water-vapor imagery this morning shows a negatively tilted, large-scale mid to upper-level trough centered over the Dakotas southeastward through the mid MS Valley and Ozarks. Several thunderstorms clusters are ongoing within a larger corridor of convection from the OH Valley southwestward into the lower MS Valley. This activity is occurring to the east/southeast of a gradually filling cyclone forecast to move from the lower MO Valley eastward into the southwest Great Lakes by late tonight. Little change was made to the previous outlook due in part to general consistency in model guidance and observational trends noted this morning. Richer low-level moisture from west-central KY southward into the Gulf Coast states will contribute to a moderate to very unstable airmass by the early afternoon in areas void of recent convective outflow and associated cloud debris. Scattered to numerous thunderstorms are forecast to develop coincident with the diurnal heating cycle. Forecast hodographs coupled with progged buoyancy will support a mix of supercells and line segments this afternoon. The initial supercell activity will potentially yield a threat for large to very large hail. It appears the greatest risk for supercell tornadoes may exist from northern MS east-northeastward into middle TN. Morning convection and associated destabilization concerns preclude higher tornado risk probabilities. However, models continue to indicate upscale growth into several bands will occur late this afternoon through the late evening as storms move east across the Enhanced (level 3) Risk area. Have enlarged severe/damaging wind probabilities across AL/GA to account for confidence in a continuation of a wind threat persisting through the evening. ...IL/IN... Within the left-exit region of a cyclonically curved mid to upper speed max, a dry slot and attendant corridor of steep lapse rates will likely evolve across portions of MO to IL/IN from midday into the afternoon. Destabilization will likely be less across the mid MS Valley eastward into IN, with the richer moisture confined south of residual outflow and warm frontal zone over the lower OH Valley. Nonetheless, isolated to scattered severe thunderstorms are possible later today into the evening via a mix of shorter-lived supercells and organized multicells. Isolated to scattered coverage of severe and all hazards are possible with the stronger storms before this activity diminishes during the evening. ..Smith/Marsh.. 05/20/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue May 20 2025 Valid 201300Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID/DEEP SOUTH TO TN VALLEY AND CUMBERLAND PLATEAU... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...Mid/Deep South to the TN/Lower OH Valleys and Cumberland Plateau... Water-vapor imagery this morning shows a negatively tilted, large-scale mid to upper-level trough centered over the Dakotas southeastward through the mid MS Valley and Ozarks. Several thunderstorms clusters are ongoing within a larger corridor of convection from the OH Valley southwestward into the lower MS Valley. This activity is occurring to the east/southeast of a gradually filling cyclone forecast to move from the lower MO Valley eastward into the southwest Great Lakes by late tonight. Little change was made to the previous outlook due in part to general consistency in model guidance and observational trends noted this morning. Richer low-level moisture from west-central KY southward into the Gulf Coast states will contribute to a moderate to very unstable airmass by the early afternoon in areas void of recent convective outflow and associated cloud debris. Scattered to numerous thunderstorms are forecast to develop coincident with the diurnal heating cycle. Forecast hodographs coupled with progged buoyancy will support a mix of supercells and line segments this afternoon. The initial supercell activity will potentially yield a threat for large to very large hail. It appears the greatest risk for supercell tornadoes may exist from northern MS east-northeastward into middle TN. Morning convection and associated destabilization concerns preclude higher tornado risk probabilities. However, models continue to indicate upscale growth into several bands will occur late this afternoon through the late evening as storms move east across the Enhanced (level 3) Risk area. Have enlarged severe/damaging wind probabilities across AL/GA to account for confidence in a continuation of a wind threat persisting through the evening. ...IL/IN... Within the left-exit region of a cyclonically curved mid to upper speed max, a dry slot and attendant corridor of steep lapse rates will likely evolve across portions of MO to IL/IN from midday into the afternoon. Destabilization will likely be less across the mid MS Valley eastward into IN, with the richer moisture confined south of residual outflow and warm frontal zone over the lower OH Valley. Nonetheless, isolated to scattered severe thunderstorms are possible later today into the evening via a mix of shorter-lived supercells and organized multicells. Isolated to scattered coverage of severe and all hazards are possible with the stronger storms before this activity diminishes during the evening. ..Smith/Marsh.. 05/20/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue May 20 2025 Valid 201300Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID/DEEP SOUTH TO TN VALLEY AND CUMBERLAND PLATEAU... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...Mid/Deep South to the TN/Lower OH Valleys and Cumberland Plateau... Water-vapor imagery this morning shows a negatively tilted, large-scale mid to upper-level trough centered over the Dakotas southeastward through the mid MS Valley and Ozarks. Several thunderstorms clusters are ongoing within a larger corridor of convection from the OH Valley southwestward into the lower MS Valley. This activity is occurring to the east/southeast of a gradually filling cyclone forecast to move from the lower MO Valley eastward into the southwest Great Lakes by late tonight. Little change was made to the previous outlook due in part to general consistency in model guidance and observational trends noted this morning. Richer low-level moisture from west-central KY southward into the Gulf Coast states will contribute to a moderate to very unstable airmass by the early afternoon in areas void of recent convective outflow and associated cloud debris. Scattered to numerous thunderstorms are forecast to develop coincident with the diurnal heating cycle. Forecast hodographs coupled with progged buoyancy will support a mix of supercells and line segments this afternoon. The initial supercell activity will potentially yield a threat for large to very large hail. It appears the greatest risk for supercell tornadoes may exist from northern MS east-northeastward into middle TN. Morning convection and associated destabilization concerns preclude higher tornado risk probabilities. However, models continue to indicate upscale growth into several bands will occur late this afternoon through the late evening as storms move east across the Enhanced (level 3) Risk area. Have enlarged severe/damaging wind probabilities across AL/GA to account for confidence in a continuation of a wind threat persisting through the evening. ...IL/IN... Within the left-exit region of a cyclonically curved mid to upper speed max, a dry slot and attendant corridor of steep lapse rates will likely evolve across portions of MO to IL/IN from midday into the afternoon. Destabilization will likely be less across the mid MS Valley eastward into IN, with the richer moisture confined south of residual outflow and warm frontal zone over the lower OH Valley. Nonetheless, isolated to scattered severe thunderstorms are possible later today into the evening via a mix of shorter-lived supercells and organized multicells. Isolated to scattered coverage of severe and all hazards are possible with the stronger storms before this activity diminishes during the evening. ..Smith/Marsh.. 05/20/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue May 20 2025 Valid 201300Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID/DEEP SOUTH TO TN VALLEY AND CUMBERLAND PLATEAU... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...Mid/Deep South to the TN/Lower OH Valleys and Cumberland Plateau... Water-vapor imagery this morning shows a negatively tilted, large-scale mid to upper-level trough centered over the Dakotas southeastward through the mid MS Valley and Ozarks. Several thunderstorms clusters are ongoing within a larger corridor of convection from the OH Valley southwestward into the lower MS Valley. This activity is occurring to the east/southeast of a gradually filling cyclone forecast to move from the lower MO Valley eastward into the southwest Great Lakes by late tonight. Little change was made to the previous outlook due in part to general consistency in model guidance and observational trends noted this morning. Richer low-level moisture from west-central KY southward into the Gulf Coast states will contribute to a moderate to very unstable airmass by the early afternoon in areas void of recent convective outflow and associated cloud debris. Scattered to numerous thunderstorms are forecast to develop coincident with the diurnal heating cycle. Forecast hodographs coupled with progged buoyancy will support a mix of supercells and line segments this afternoon. The initial supercell activity will potentially yield a threat for large to very large hail. It appears the greatest risk for supercell tornadoes may exist from northern MS east-northeastward into middle TN. Morning convection and associated destabilization concerns preclude higher tornado risk probabilities. However, models continue to indicate upscale growth into several bands will occur late this afternoon through the late evening as storms move east across the Enhanced (level 3) Risk area. Have enlarged severe/damaging wind probabilities across AL/GA to account for confidence in a continuation of a wind threat persisting through the evening. ...IL/IN... Within the left-exit region of a cyclonically curved mid to upper speed max, a dry slot and attendant corridor of steep lapse rates will likely evolve across portions of MO to IL/IN from midday into the afternoon. Destabilization will likely be less across the mid MS Valley eastward into IN, with the richer moisture confined south of residual outflow and warm frontal zone over the lower OH Valley. Nonetheless, isolated to scattered severe thunderstorms are possible later today into the evening via a mix of shorter-lived supercells and organized multicells. Isolated to scattered coverage of severe and all hazards are possible with the stronger storms before this activity diminishes during the evening. ..Smith/Marsh.. 05/20/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue May 20 2025 Valid 201300Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID/DEEP SOUTH TO TN VALLEY AND CUMBERLAND PLATEAU... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...Mid/Deep South to the TN/Lower OH Valleys and Cumberland Plateau... Water-vapor imagery this morning shows a negatively tilted, large-scale mid to upper-level trough centered over the Dakotas southeastward through the mid MS Valley and Ozarks. Several thunderstorms clusters are ongoing within a larger corridor of convection from the OH Valley southwestward into the lower MS Valley. This activity is occurring to the east/southeast of a gradually filling cyclone forecast to move from the lower MO Valley eastward into the southwest Great Lakes by late tonight. Little change was made to the previous outlook due in part to general consistency in model guidance and observational trends noted this morning. Richer low-level moisture from west-central KY southward into the Gulf Coast states will contribute to a moderate to very unstable airmass by the early afternoon in areas void of recent convective outflow and associated cloud debris. Scattered to numerous thunderstorms are forecast to develop coincident with the diurnal heating cycle. Forecast hodographs coupled with progged buoyancy will support a mix of supercells and line segments this afternoon. The initial supercell activity will potentially yield a threat for large to very large hail. It appears the greatest risk for supercell tornadoes may exist from northern MS east-northeastward into middle TN. Morning convection and associated destabilization concerns preclude higher tornado risk probabilities. However, models continue to indicate upscale growth into several bands will occur late this afternoon through the late evening as storms move east across the Enhanced (level 3) Risk area. Have enlarged severe/damaging wind probabilities across AL/GA to account for confidence in a continuation of a wind threat persisting through the evening. ...IL/IN... Within the left-exit region of a cyclonically curved mid to upper speed max, a dry slot and attendant corridor of steep lapse rates will likely evolve across portions of MO to IL/IN from midday into the afternoon. Destabilization will likely be less across the mid MS Valley eastward into IN, with the richer moisture confined south of residual outflow and warm frontal zone over the lower OH Valley. Nonetheless, isolated to scattered severe thunderstorms are possible later today into the evening via a mix of shorter-lived supercells and organized multicells. Isolated to scattered coverage of severe and all hazards are possible with the stronger storms before this activity diminishes during the evening. ..Smith/Marsh.. 05/20/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue May 20 2025 Valid 201300Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID/DEEP SOUTH TO TN VALLEY AND CUMBERLAND PLATEAU... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...Mid/Deep South to the TN/Lower OH Valleys and Cumberland Plateau... Water-vapor imagery this morning shows a negatively tilted, large-scale mid to upper-level trough centered over the Dakotas southeastward through the mid MS Valley and Ozarks. Several thunderstorms clusters are ongoing within a larger corridor of convection from the OH Valley southwestward into the lower MS Valley. This activity is occurring to the east/southeast of a gradually filling cyclone forecast to move from the lower MO Valley eastward into the southwest Great Lakes by late tonight. Little change was made to the previous outlook due in part to general consistency in model guidance and observational trends noted this morning. Richer low-level moisture from west-central KY southward into the Gulf Coast states will contribute to a moderate to very unstable airmass by the early afternoon in areas void of recent convective outflow and associated cloud debris. Scattered to numerous thunderstorms are forecast to develop coincident with the diurnal heating cycle. Forecast hodographs coupled with progged buoyancy will support a mix of supercells and line segments this afternoon. The initial supercell activity will potentially yield a threat for large to very large hail. It appears the greatest risk for supercell tornadoes may exist from northern MS east-northeastward into middle TN. Morning convection and associated destabilization concerns preclude higher tornado risk probabilities. However, models continue to indicate upscale growth into several bands will occur late this afternoon through the late evening as storms move east across the Enhanced (level 3) Risk area. Have enlarged severe/damaging wind probabilities across AL/GA to account for confidence in a continuation of a wind threat persisting through the evening. ...IL/IN... Within the left-exit region of a cyclonically curved mid to upper speed max, a dry slot and attendant corridor of steep lapse rates will likely evolve across portions of MO to IL/IN from midday into the afternoon. Destabilization will likely be less across the mid MS Valley eastward into IN, with the richer moisture confined south of residual outflow and warm frontal zone over the lower OH Valley. Nonetheless, isolated to scattered severe thunderstorms are possible later today into the evening via a mix of shorter-lived supercells and organized multicells. Isolated to scattered coverage of severe and all hazards are possible with the stronger storms before this activity diminishes during the evening. ..Smith/Marsh.. 05/20/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue May 20 2025 Valid 201300Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID/DEEP SOUTH TO TN VALLEY AND CUMBERLAND PLATEAU... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...Mid/Deep South to the TN/Lower OH Valleys and Cumberland Plateau... Water-vapor imagery this morning shows a negatively tilted, large-scale mid to upper-level trough centered over the Dakotas southeastward through the mid MS Valley and Ozarks. Several thunderstorms clusters are ongoing within a larger corridor of convection from the OH Valley southwestward into the lower MS Valley. This activity is occurring to the east/southeast of a gradually filling cyclone forecast to move from the lower MO Valley eastward into the southwest Great Lakes by late tonight. Little change was made to the previous outlook due in part to general consistency in model guidance and observational trends noted this morning. Richer low-level moisture from west-central KY southward into the Gulf Coast states will contribute to a moderate to very unstable airmass by the early afternoon in areas void of recent convective outflow and associated cloud debris. Scattered to numerous thunderstorms are forecast to develop coincident with the diurnal heating cycle. Forecast hodographs coupled with progged buoyancy will support a mix of supercells and line segments this afternoon. The initial supercell activity will potentially yield a threat for large to very large hail. It appears the greatest risk for supercell tornadoes may exist from northern MS east-northeastward into middle TN. Morning convection and associated destabilization concerns preclude higher tornado risk probabilities. However, models continue to indicate upscale growth into several bands will occur late this afternoon through the late evening as storms move east across the Enhanced (level 3) Risk area. Have enlarged severe/damaging wind probabilities across AL/GA to account for confidence in a continuation of a wind threat persisting through the evening. ...IL/IN... Within the left-exit region of a cyclonically curved mid to upper speed max, a dry slot and attendant corridor of steep lapse rates will likely evolve across portions of MO to IL/IN from midday into the afternoon. Destabilization will likely be less across the mid MS Valley eastward into IN, with the richer moisture confined south of residual outflow and warm frontal zone over the lower OH Valley. Nonetheless, isolated to scattered severe thunderstorms are possible later today into the evening via a mix of shorter-lived supercells and organized multicells. Isolated to scattered coverage of severe and all hazards are possible with the stronger storms before this activity diminishes during the evening. ..Smith/Marsh.. 05/20/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue May 20 2025 Valid 201300Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID/DEEP SOUTH TO TN VALLEY AND CUMBERLAND PLATEAU... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...Mid/Deep South to the TN/Lower OH Valleys and Cumberland Plateau... Water-vapor imagery this morning shows a negatively tilted, large-scale mid to upper-level trough centered over the Dakotas southeastward through the mid MS Valley and Ozarks. Several thunderstorms clusters are ongoing within a larger corridor of convection from the OH Valley southwestward into the lower MS Valley. This activity is occurring to the east/southeast of a gradually filling cyclone forecast to move from the lower MO Valley eastward into the southwest Great Lakes by late tonight. Little change was made to the previous outlook due in part to general consistency in model guidance and observational trends noted this morning. Richer low-level moisture from west-central KY southward into the Gulf Coast states will contribute to a moderate to very unstable airmass by the early afternoon in areas void of recent convective outflow and associated cloud debris. Scattered to numerous thunderstorms are forecast to develop coincident with the diurnal heating cycle. Forecast hodographs coupled with progged buoyancy will support a mix of supercells and line segments this afternoon. The initial supercell activity will potentially yield a threat for large to very large hail. It appears the greatest risk for supercell tornadoes may exist from northern MS east-northeastward into middle TN. Morning convection and associated destabilization concerns preclude higher tornado risk probabilities. However, models continue to indicate upscale growth into several bands will occur late this afternoon through the late evening as storms move east across the Enhanced (level 3) Risk area. Have enlarged severe/damaging wind probabilities across AL/GA to account for confidence in a continuation of a wind threat persisting through the evening. ...IL/IN... Within the left-exit region of a cyclonically curved mid to upper speed max, a dry slot and attendant corridor of steep lapse rates will likely evolve across portions of MO to IL/IN from midday into the afternoon. Destabilization will likely be less across the mid MS Valley eastward into IN, with the richer moisture confined south of residual outflow and warm frontal zone over the lower OH Valley. Nonetheless, isolated to scattered severe thunderstorms are possible later today into the evening via a mix of shorter-lived supercells and organized multicells. Isolated to scattered coverage of severe and all hazards are possible with the stronger storms before this activity diminishes during the evening. ..Smith/Marsh.. 05/20/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 AM CDT Tue May 20 2025 Valid 201300Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID/DEEP SOUTH TO TN VALLEY AND CUMBERLAND PLATEAU... ...SUMMARY... Multiple rounds of severe thunderstorms are expected today through this evening, centered on the Mid/Deep South, Tennessee/Lower Ohio Valleys, and Cumberland Plateau. Tornadoes, some of which could be strong, along with scattered to widespread damaging winds, and large to isolated significant severe hail will be possible. ...Mid/Deep South to the TN/Lower OH Valleys and Cumberland Plateau... Water-vapor imagery this morning shows a negatively tilted, large-scale mid to upper-level trough centered over the Dakotas southeastward through the mid MS Valley and Ozarks. Several thunderstorms clusters are ongoing within a larger corridor of convection from the OH Valley southwestward into the lower MS Valley. This activity is occurring to the east/southeast of a gradually filling cyclone forecast to move from the lower MO Valley eastward into the southwest Great Lakes by late tonight. Little change was made to the previous outlook due in part to general consistency in model guidance and observational trends noted this morning. Richer low-level moisture from west-central KY southward into the Gulf Coast states will contribute to a moderate to very unstable airmass by the early afternoon in areas void of recent convective outflow and associated cloud debris. Scattered to numerous thunderstorms are forecast to develop coincident with the diurnal heating cycle. Forecast hodographs coupled with progged buoyancy will support a mix of supercells and line segments this afternoon. The initial supercell activity will potentially yield a threat for large to very large hail. It appears the greatest risk for supercell tornadoes may exist from northern MS east-northeastward into middle TN. Morning convection and associated destabilization concerns preclude higher tornado risk probabilities. However, models continue to indicate upscale growth into several bands will occur late this afternoon through the late evening as storms move east across the Enhanced (level 3) Risk area. Have enlarged severe/damaging wind probabilities across AL/GA to account for confidence in a continuation of a wind threat persisting through the evening. ...IL/IN... Within the left-exit region of a cyclonically curved mid to upper speed max, a dry slot and attendant corridor of steep lapse rates will likely evolve across portions of MO to IL/IN from midday into the afternoon. Destabilization will likely be less across the mid MS Valley eastward into IN, with the richer moisture confined south of residual outflow and warm frontal zone over the lower OH Valley. Nonetheless, isolated to scattered severe thunderstorms are possible later today into the evening via a mix of shorter-lived supercells and organized multicells. Isolated to scattered coverage of severe and all hazards are possible with the stronger storms before this activity diminishes during the evening. ..Smith/Marsh.. 05/20/2025 Read more

Public Severe Weather Outlook
PUBLIC SEVERE WEATHER OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0840 PM CDT MON MAY 19 2025 ...Severe thunderstorms expected over parts of the southern Plains into the Ozarks and mid Mississippi Valley this evening and overnight... * LOCATIONS... Western and Northern Arkansas Missouri Far Eastern Oklahoma North-Central and Northeast Texas Southern Illinois * HAZARDS... Widespread damaging winds, some hurricane force Several tornadoes, a few intense Scattered large hail, some baseball size * SUMMARY... A significant severe weather episode should continue tonight across parts of the South-Central States. Strong tornadoes, scattered to widespread damaging wind swaths, and very large hail remain possible. Preparedness actions... Tornadoes at night can be particularly dangerous because they are usually fast-moving and difficult to see. Stay tuned to NOAA Weather Radio, weather.gov, or other media for watches and warnings. A tornado watch means that conditions are favorable for tornadoes to form during the next several hours. If a tornado warning is issued for your area, move to a place of safety, ideally in a basement or interior room on the lowest floor of a sturdy building. Read more

Public Severe Weather Outlook
PUBLIC SEVERE WEATHER OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0840 PM CDT MON MAY 19 2025 ...Severe thunderstorms expected over parts of the southern Plains into the Ozarks and mid Mississippi Valley this evening and overnight... * LOCATIONS... Western and Northern Arkansas Missouri Far Eastern Oklahoma North-Central and Northeast Texas Southern Illinois * HAZARDS... Widespread damaging winds, some hurricane force Several tornadoes, a few intense Scattered large hail, some baseball size * SUMMARY... A significant severe weather episode should continue tonight across parts of the South-Central States. Strong tornadoes, scattered to widespread damaging wind swaths, and very large hail remain possible. Preparedness actions... Tornadoes at night can be particularly dangerous because they are usually fast-moving and difficult to see. Stay tuned to NOAA Weather Radio, weather.gov, or other media for watches and warnings. A tornado watch means that conditions are favorable for tornadoes to form during the next several hours. If a tornado warning is issued for your area, move to a place of safety, ideally in a basement or interior room on the lowest floor of a sturdy building. Read more

Public Severe Weather Outlook
PUBLIC SEVERE WEATHER OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0840 PM CDT MON MAY 19 2025 ...Severe thunderstorms expected over parts of the southern Plains into the Ozarks and mid Mississippi Valley this evening and overnight... * LOCATIONS... Western and Northern Arkansas Missouri Far Eastern Oklahoma North-Central and Northeast Texas Southern Illinois * HAZARDS... Widespread damaging winds, some hurricane force Several tornadoes, a few intense Scattered large hail, some baseball size * SUMMARY... A significant severe weather episode should continue tonight across parts of the South-Central States. Strong tornadoes, scattered to widespread damaging wind swaths, and very large hail remain possible. Preparedness actions... Tornadoes at night can be particularly dangerous because they are usually fast-moving and difficult to see. Stay tuned to NOAA Weather Radio, weather.gov, or other media for watches and warnings. A tornado watch means that conditions are favorable for tornadoes to form during the next several hours. If a tornado warning is issued for your area, move to a place of safety, ideally in a basement or interior room on the lowest floor of a sturdy building. Read more

Public Severe Weather Outlook
PUBLIC SEVERE WEATHER OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0840 PM CDT MON MAY 19 2025 ...Severe thunderstorms expected over parts of the southern Plains into the Ozarks and mid Mississippi Valley this evening and overnight... * LOCATIONS... Western and Northern Arkansas Missouri Far Eastern Oklahoma North-Central and Northeast Texas Southern Illinois * HAZARDS... Widespread damaging winds, some hurricane force Several tornadoes, a few intense Scattered large hail, some baseball size * SUMMARY... A significant severe weather episode should continue tonight across parts of the South-Central States. Strong tornadoes, scattered to widespread damaging wind swaths, and very large hail remain possible. Preparedness actions... Tornadoes at night can be particularly dangerous because they are usually fast-moving and difficult to see. Stay tuned to NOAA Weather Radio, weather.gov, or other media for watches and warnings. A tornado watch means that conditions are favorable for tornadoes to form during the next several hours. If a tornado warning is issued for your area, move to a place of safety, ideally in a basement or interior room on the lowest floor of a sturdy building. Read more

Public Severe Weather Outlook
PUBLIC SEVERE WEATHER OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0840 PM CDT MON MAY 19 2025 ...Severe thunderstorms expected over parts of the southern Plains into the Ozarks and mid Mississippi Valley this evening and overnight... * LOCATIONS... Western and Northern Arkansas Missouri Far Eastern Oklahoma North-Central and Northeast Texas Southern Illinois * HAZARDS... Widespread damaging winds, some hurricane force Several tornadoes, a few intense Scattered large hail, some baseball size * SUMMARY... A significant severe weather episode should continue tonight across parts of the South-Central States. Strong tornadoes, scattered to widespread damaging wind swaths, and very large hail remain possible. Preparedness actions... Tornadoes at night can be particularly dangerous because they are usually fast-moving and difficult to see. Stay tuned to NOAA Weather Radio, weather.gov, or other media for watches and warnings. A tornado watch means that conditions are favorable for tornadoes to form during the next several hours. If a tornado warning is issued for your area, move to a place of safety, ideally in a basement or interior room on the lowest floor of a sturdy building. Read more

000
ABPZ20 KNHC 201123
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Tue May 20 2025

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

Eastern East Pacific:
An area of low pressure could form by this weekend into early next
week several hundred miles south of the southern coast of Mexico.
Conditions appear favorable for some development of this system
thereafter while it moves westward to west-northwestward at around
10 to 15 mph.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Kelly

MD 0900 CONCERNING SEVERE THUNDERSTORM WATCH 300... FOR NORTHEAST TEXAS...NORTHWEST LOUISIANA...INTO CENTRAL/EASTERN ARKANSAS
Mesoscale Discussion 0900 NWS Storm Prediction Center Norman OK 0421 AM CDT Tue May 20 2025 Areas affected...northeast Texas...northwest Louisiana...into central/eastern Arkansas Concerning...Severe Thunderstorm Watch 300... Valid 200921Z - 201015Z The severe weather threat for Severe Thunderstorm Watch 300 continues. SUMMARY...Thunderstorms will continue to fluctuate in their intensity through the morning, episodically reaching an intensity level capable of damaging thunderstorm winds. A local extension to Severe Thunderstorm Watch #300 was coordinated with WFO Little Rock. DISCUSSION...Several clusters/lines of thunderstorms are exiting northeast Texas moving into northwest Louisiana/southwest Arkansas and across central Arkansas. The storms remain in a favorable environment for severe (MUCAPE around 1000-1500 J/kg and effective shear around 50 knots. As we approach the diurnal minimum in the convective cycle, and as the storms continue to pull away from the best large-scale forcing for ascent, the long-term trend in thunderstorms intensity had been down. However, recent reflectivity and velocity data from area radars has shown an uptick in intensity across area. The expectation is that thunderstorm updrafts will continue to episodically pose a risk for small hail, and more likely for damaging wind gusts for at least another couple of hours. A local extension in space for existing Severe Thunderstorm Watch #300 was coordinated with WFO Little Rock to add additional areas of Arkansas to the watch. ..Marsh/Smith.. 05/20/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MEG...LZK...SHV...FWD... LAT...LON 32629569 34459399 35639256 35599101 33999110 33739260 32619331 32629569 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more