SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Aug 06 2024 Valid 061630Z - 071200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING FROM EASTERN OHIO ACROSS MUCH OF PENNSYLVANIA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF MONTANA INTO WESTERN SOUTH DAKOTA...THE COASTAL CAROLINAS...AND ACROSS PARTS OF ARIZONA... ...SUMMARY... Severe thunderstorms capable of damaging winds, hail, and isolated tornadoes will affect areas from northern Ohio into New Jersey today. Others areas of concerns include much of Montana into western South Dakota, the coastal Carolinas, and across parts of Arizona. ...OH to NJ... Recent water vapor loop shows a well-defined and fast-moving shortwave trough over Lower MI. This feature will track eastward across parts of OH/PA/NY today, along a corridor of strong heating/destabilization. This will lead to multiple clusters of intense convection capable of damaging winds, large hail. Winds aloft are seasonably strong, but low-level winds are relatively weak. Some increase in low-level winds/shear may occur later today, posing some risk of isolated tornadoes as well. ...MT/WY/SD... Multiple minor shortwave troughs will rotate through the top of the ridge over MT/WY today, while mid-level winds strengthen. A plume of mid-level moisture/lift ahead of these features will lead to scattered thunderstorms over the mountains of western MT by mid afternoon. This activity will spread into the adjacent Plains and intensify. Forecast soundings show sufficient deep-layer shear to support supercell storm structures capable of large hail and damaging wind gusts through the afternoon and evening. ...AZ... A weak upper low is present this morning over northern Mexico tracking slowly westward. Enhanced easterly mid level winds around the northern periphery of the low are spreading westward across AZ today. A few clusters of thunderstorms are likely to form over the mountains of eastern AZ and propagate westward through the evening into the lower deserts. This pattern appears favorable for a more organized damaging wind event across parts of AZ, although the details of thunderstorm coverage/intensity over the higher terrain of eastern AZ will help dictate the overall threat later today. ...Carolinas... TS Debby remains over southeast GA, with bands of offshore thunderstorms tracking inland along the coasts of SC/southeast NC. Sufficient low-level shear will remain in place through the afternoon and evening for a risk of transient mesocyclones and a few tornadoes through the forecast period. ..Hart/Halbert/Lyons.. 08/06/2024 Read more

WW 0604 Status Updates
STATUS REPORT ON WW 604 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 WNW FDY TO 15 NNW TOL TO 40 SE DTW. WW 604 WILL BE ALLOWED TO EXPIRE AT 061900Z. ..SQUITIERI..08/06/24 ATTN...WFO...IWX...GRR...DTX...CLE... STATUS REPORT FOR WT 604 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS OHC095-123-143-147-173-061900- OH . OHIO COUNTIES INCLUDED ARE LUCAS OTTAWA SANDUSKY SENECA WOOD LEZ142-143-163-061900- CW . ADJACENT COASTAL WATERS INCLUDED ARE MAUMEE BAY TO RENO BEACH OH RENO BEACH TO THE ISLANDS OH RENO BEACH TO THE ISLANDS OH BEYOND 5NM OFF SHORELINE TO US-CANADIAN BORDER THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE Read more

WW 604 TORNADO IN MI OH LE 061205Z - 061900Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 604 NWS Storm Prediction Center Norman OK 805 AM EDT Tue Aug 6 2024 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Extreme northeastern Indiana Southern Lower Michigan Northwestern Ohio Lake Erie * Effective this Tuesday morning and afternoon from 805 AM until 300 PM EDT. * Primary threats include... A couple tornadoes possible Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...A small cluster of thunderstorms -- including a strong supercell that has intensified over southwestern Lower MI, should move east-southeastward along a baroclinic zone through the remainder of the morning. This environment will maintain enough vertical shear for tornado potential, as well as some potential increase in instability. Upscale growth into a damaging-wind- producing bow or cluster also is possible. The tornado watch area is approximately along and 30 statute miles north and south of a line from 15 miles southwest of Kalamazoo MI to 45 miles east of Toledo OH. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && OTHER WATCH INFORMATION...CONTINUE...WW 603... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 28030. ...Edwards Read more

WW 0605 Status Updates
STATUS FOR WATCH 0605 HAS NOT BEEN ISSUED YET Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0758 AM CDT Tue Aug 06 2024 Valid 061300Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF MONTANA INTO WESTERN SOUTH DAKOTA...AS WELL AS FROM PARTS OF LOWER MICHIGAN INTO NEW JERSEY...THE COASTAL CAROLINAS...AND ACROSS PARTS OF ARIZONA... ...SUMMARY... Severe-thunderstorm potential exists today over much of Montana into western South Dakota, as well as from parts of Lower Michigan into New Jersey, the coastal Carolinas, and across parts of Arizona. ...Synopsis... In mid/upper levels, a longstanding, large, western CONUS anticyclone -- centered initially over southern CO -- is expected to become more compressed on the northern and southwestern fringes, while the center retrogrades back across the Four Corners region. This will occur in response to shortwave developments in the northern stream and subtropical easterlies. For the latter, a well- defined trough is evident in moisture-channel imagery over portions of southern NM, far west TX, and northwestern MX, with an embedded low over west-central Chihuahua. The trough should proceed westward through the period, reaching western Sonora and southern AZ by 12Z tomorrow. North of the mid/upper high, an accelerating, nearly zonal northern stream is forecast from the interior Northwest to the northern Upper Midwest, as heights fall south of a progressive synoptic trough over western/central Canada. This will take an initially slow-moving shortwave trough over coastal WA/OR and accelerate it eastward into the northern Rockies around 00Z, then to eastern MT by the end of the period. Another, weaker perturbation now near the CA/OR/NV border junction should accelerate northeastward today as well, preceding the Northwest trough in an eastward-turning path across southern MT. This perturbation should reach the central Dakotas by 12Z. Farther downshear, a convectively enhanced shortwave trough with embedded MCV is evident over the southern Lake Michigan region. This feature should move eastward across Lower MI and southern ON to the Lower Great Lakes by 00Z, then across the northern Mid-Atlantic and most of New England by 12Z. At the surface, 11Z analysis showed a wavy, quasistationary front from a low near ORD east-southeastward across northern portions of IN/OH/PA to southeastern NY and coastal southern New England. A cold front extended from the low southwestward over northern MO, east-central KS, to an elongated low-pressure area over the southern KS/CO border vicinity. The low is expected to migrate eastward along the frontal zone and weaken today, but perhaps slower than model progs, given the presence of the MCV/shortwave trough supporting it. By 00Z, the frontal zone should extend from near the southern New England Coast across central/northern PA and northern OH, while moving south as a cold front across central IN, southern IL, the Ozarks, to central/western OK, becoming quasistationary again to a low over southeastern CO. Surface cyclogenesis is expected late tonight across eastern WY, effectively replacing the prior southeastern CO low along a lee trough. ...Great Lakes to northern Mid-Atlantic... Scattered thunderstorms -- both discrete and in clusters -- are expected near the frontal zone today from the southern Upper Great Lakes eastward. The initial activity is apparent over southern Lower MI ahead of the shortwave trough. This includes an intense, heavy-precip supercell that may maintain a tornado threat on the north end of a favorably unstable environment in the frontal zone, juxtaposed with strong low-level shear. Upscale growth into a bowing clusters also may occur, following the frontal-related instability gradient east-southeastward. See Tornado Watch 604 and related SPC mesoscale discussions for near-term coverage. This activity, or later/foregoing development near the front, will encounter favorably moist and gradually more unstable/heated inflow air today. Supercells and bowing clusters will remain a threat, with all severe hazards possible. Surface dewpoints along and south of the front -- as well as a sort distance to its north -- will remain in the upper 60s to low 70s F (locally higher) over the outlook corridor, offsetting modest mid/upper-level lapse rates to yield MLCAPE in the 1500-2000 J/kg range. Enhancements to low-level and deep shear are expected in the mass response immediately preceding the shortwave trough, combining with backed surface winds along and north of the front to contribute to 150-300 J/kg effective SRH from southern Lower MI into northernmost OH, shifting into western PA later this afternoon. One or two corridors of relatively dense/greater damaging wind potential may develop within the current 15%/"slight" area, depending on timing/intensity of convective-cluster evolution. ...Northern/central High Plains and adjacent foothills... A couple rounds of strong-severe thunderstorms are possible across the northern High Plains: 1. Convection developing by midafternoon over higher terrain of southwestern MT, moving northeastward to eastward over southern/central MT the remainder of the afternoon into evening. Activity may aggregate upscale to a mainly wind-producing MCS with sporadic severe gusts, though isolated, marginally severe hail may occur as well. This convection should form as a zone of increasing large-scale lift (preceding the leading/weaker shortwave trough mentioned above) superimposes favorable diurnal heating of higher terrain and related preferential removal of MLCINH. This convection should move into lower elevations characterized by deep, well- heated/mixed boundary layers, but with enough low-level moisture to maintain and perhaps strengthen the convection as it crosses the outlook area. Activity should encounter progressively more-stable inflow air eastward into the western Dakotas tonight, leading to weakening. 2. Development over the northern Rockies and adjacent foothills of northwestern MT from late afternoon into evening, proceeding eastward to east-southeastward across northern MT, with large hail and locally strong-severe gusts possible. Compared to farther south, expect somewhat more low-level moisture, in a pocket of favorable boundary-layer theta-e undisturbed by the slightly earlier activity to the south and southeast, as well as stronger deep shear (45-50-kt effective-shear magnitudes) in support of supercell potential. Peak MLCAPE of 500-1200 J/kg is expected, supported by lower-elevation surface dewpoints commonly in the 50s F, and residual steep low-level lapse rates from diurnal heating. Long, relatively straight hodographs will support hail potential from any sustained supercells -- either left- or right-moving (with splitting storms possible). Eastward extent of the threat into tonight is uncertain, given the potential for outflow from the higher-based, drier-rooted southern complex to advect into the path of this activity somewhere over central to northeastern MT. ...AZ... Widely scattered to scattered thunderstorms are expected to form this afternoon over the higher terrain of north-central through southeastern AZ, roughly from east of IGM southeastward past the SAD area, as well as on some of the smaller ranges to the south of the Mogollon Rim. Activity should move over deserts/valleys to the west and southwest across southern AZ, offering areas of strong-severe gusts as outflows aggregate and additional, discretely propagating development occurs atop the cold pools. As the northern MX mid/upper trough shifts westward, height falls and a somewhat tightened mid/upper gradient will shift westward over southern AZ, leading to regional enhancement of midtropospheric easterlies to influence convective motion and ultimate forward propagation. Large-scale ascent/DCVA also is expected in advance of the trough, overlying diurnally heated/deeply mixed boundary layers to ensure steep deep-layer lapse rates. Sufficient low-level moisture (9-13 g/kg mean mixing ratios) will remain through the vertical-mixing process to support 1000-1500 J/kg preconvective MLCAPE, as well as pulses of newer development when forced ascent occurs above outflow. These processes should drive outflow, with channels of locally severe wind, across south-central/southwestern AZ and potentially into the lower Colorado River Valley and into portions of southeastern CA, before activity dissipates tonight. ...Coastal Carolinas... The threat for a few tornadoes will continue through today, and perhaps into the evening, as T.S. Debby moves very slowly eastward to northeastward, per NHC forecasts. With Debby potentially moving slightly offshore, the cyclone should maintain substantial southeasterly inflow from a large, favorably high-theta-e boundary layer over the Gulf Stream. Within its northeastern quadrant, and seaward of a large area of stabilizing rain a short distance inland, the development of sporadic middle/outer-band supercells will remain possible offshore, with tornado potential for roughly a couple counties inland until cells encounter more prohibitively low-buoyancy inflow air. Roughly 150-300 J/kg effective SRH and favorably enlarged hodographs will support this threat. See SPC Tornado Watch 603 and related mesoscale discussions for the latest near-term guidance on tornado potential. Refer to NHC advisories for the latest track/intensity guidance for Debby, as well as tropical watches/warnings. ..Edwards.. 08/06/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0758 AM CDT Tue Aug 06 2024 Valid 061300Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF MONTANA INTO WESTERN SOUTH DAKOTA...AS WELL AS FROM PARTS OF LOWER MICHIGAN INTO NEW JERSEY...THE COASTAL CAROLINAS...AND ACROSS PARTS OF ARIZONA... ...SUMMARY... Severe-thunderstorm potential exists today over much of Montana into western South Dakota, as well as from parts of Lower Michigan into New Jersey, the coastal Carolinas, and across parts of Arizona. ...Synopsis... In mid/upper levels, a longstanding, large, western CONUS anticyclone -- centered initially over southern CO -- is expected to become more compressed on the northern and southwestern fringes, while the center retrogrades back across the Four Corners region. This will occur in response to shortwave developments in the northern stream and subtropical easterlies. For the latter, a well- defined trough is evident in moisture-channel imagery over portions of southern NM, far west TX, and northwestern MX, with an embedded low over west-central Chihuahua. The trough should proceed westward through the period, reaching western Sonora and southern AZ by 12Z tomorrow. North of the mid/upper high, an accelerating, nearly zonal northern stream is forecast from the interior Northwest to the northern Upper Midwest, as heights fall south of a progressive synoptic trough over western/central Canada. This will take an initially slow-moving shortwave trough over coastal WA/OR and accelerate it eastward into the northern Rockies around 00Z, then to eastern MT by the end of the period. Another, weaker perturbation now near the CA/OR/NV border junction should accelerate northeastward today as well, preceding the Northwest trough in an eastward-turning path across southern MT. This perturbation should reach the central Dakotas by 12Z. Farther downshear, a convectively enhanced shortwave trough with embedded MCV is evident over the southern Lake Michigan region. This feature should move eastward across Lower MI and southern ON to the Lower Great Lakes by 00Z, then across the northern Mid-Atlantic and most of New England by 12Z. At the surface, 11Z analysis showed a wavy, quasistationary front from a low near ORD east-southeastward across northern portions of IN/OH/PA to southeastern NY and coastal southern New England. A cold front extended from the low southwestward over northern MO, east-central KS, to an elongated low-pressure area over the southern KS/CO border vicinity. The low is expected to migrate eastward along the frontal zone and weaken today, but perhaps slower than model progs, given the presence of the MCV/shortwave trough supporting it. By 00Z, the frontal zone should extend from near the southern New England Coast across central/northern PA and northern OH, while moving south as a cold front across central IN, southern IL, the Ozarks, to central/western OK, becoming quasistationary again to a low over southeastern CO. Surface cyclogenesis is expected late tonight across eastern WY, effectively replacing the prior southeastern CO low along a lee trough. ...Great Lakes to northern Mid-Atlantic... Scattered thunderstorms -- both discrete and in clusters -- are expected near the frontal zone today from the southern Upper Great Lakes eastward. The initial activity is apparent over southern Lower MI ahead of the shortwave trough. This includes an intense, heavy-precip supercell that may maintain a tornado threat on the north end of a favorably unstable environment in the frontal zone, juxtaposed with strong low-level shear. Upscale growth into a bowing clusters also may occur, following the frontal-related instability gradient east-southeastward. See Tornado Watch 604 and related SPC mesoscale discussions for near-term coverage. This activity, or later/foregoing development near the front, will encounter favorably moist and gradually more unstable/heated inflow air today. Supercells and bowing clusters will remain a threat, with all severe hazards possible. Surface dewpoints along and south of the front -- as well as a sort distance to its north -- will remain in the upper 60s to low 70s F (locally higher) over the outlook corridor, offsetting modest mid/upper-level lapse rates to yield MLCAPE in the 1500-2000 J/kg range. Enhancements to low-level and deep shear are expected in the mass response immediately preceding the shortwave trough, combining with backed surface winds along and north of the front to contribute to 150-300 J/kg effective SRH from southern Lower MI into northernmost OH, shifting into western PA later this afternoon. One or two corridors of relatively dense/greater damaging wind potential may develop within the current 15%/"slight" area, depending on timing/intensity of convective-cluster evolution. ...Northern/central High Plains and adjacent foothills... A couple rounds of strong-severe thunderstorms are possible across the northern High Plains: 1. Convection developing by midafternoon over higher terrain of southwestern MT, moving northeastward to eastward over southern/central MT the remainder of the afternoon into evening. Activity may aggregate upscale to a mainly wind-producing MCS with sporadic severe gusts, though isolated, marginally severe hail may occur as well. This convection should form as a zone of increasing large-scale lift (preceding the leading/weaker shortwave trough mentioned above) superimposes favorable diurnal heating of higher terrain and related preferential removal of MLCINH. This convection should move into lower elevations characterized by deep, well- heated/mixed boundary layers, but with enough low-level moisture to maintain and perhaps strengthen the convection as it crosses the outlook area. Activity should encounter progressively more-stable inflow air eastward into the western Dakotas tonight, leading to weakening. 2. Development over the northern Rockies and adjacent foothills of northwestern MT from late afternoon into evening, proceeding eastward to east-southeastward across northern MT, with large hail and locally strong-severe gusts possible. Compared to farther south, expect somewhat more low-level moisture, in a pocket of favorable boundary-layer theta-e undisturbed by the slightly earlier activity to the south and southeast, as well as stronger deep shear (45-50-kt effective-shear magnitudes) in support of supercell potential. Peak MLCAPE of 500-1200 J/kg is expected, supported by lower-elevation surface dewpoints commonly in the 50s F, and residual steep low-level lapse rates from diurnal heating. Long, relatively straight hodographs will support hail potential from any sustained supercells -- either left- or right-moving (with splitting storms possible). Eastward extent of the threat into tonight is uncertain, given the potential for outflow from the higher-based, drier-rooted southern complex to advect into the path of this activity somewhere over central to northeastern MT. ...AZ... Widely scattered to scattered thunderstorms are expected to form this afternoon over the higher terrain of north-central through southeastern AZ, roughly from east of IGM southeastward past the SAD area, as well as on some of the smaller ranges to the south of the Mogollon Rim. Activity should move over deserts/valleys to the west and southwest across southern AZ, offering areas of strong-severe gusts as outflows aggregate and additional, discretely propagating development occurs atop the cold pools. As the northern MX mid/upper trough shifts westward, height falls and a somewhat tightened mid/upper gradient will shift westward over southern AZ, leading to regional enhancement of midtropospheric easterlies to influence convective motion and ultimate forward propagation. Large-scale ascent/DCVA also is expected in advance of the trough, overlying diurnally heated/deeply mixed boundary layers to ensure steep deep-layer lapse rates. Sufficient low-level moisture (9-13 g/kg mean mixing ratios) will remain through the vertical-mixing process to support 1000-1500 J/kg preconvective MLCAPE, as well as pulses of newer development when forced ascent occurs above outflow. These processes should drive outflow, with channels of locally severe wind, across south-central/southwestern AZ and potentially into the lower Colorado River Valley and into portions of southeastern CA, before activity dissipates tonight. ...Coastal Carolinas... The threat for a few tornadoes will continue through today, and perhaps into the evening, as T.S. Debby moves very slowly eastward to northeastward, per NHC forecasts. With Debby potentially moving slightly offshore, the cyclone should maintain substantial southeasterly inflow from a large, favorably high-theta-e boundary layer over the Gulf Stream. Within its northeastern quadrant, and seaward of a large area of stabilizing rain a short distance inland, the development of sporadic middle/outer-band supercells will remain possible offshore, with tornado potential for roughly a couple counties inland until cells encounter more prohibitively low-buoyancy inflow air. Roughly 150-300 J/kg effective SRH and favorably enlarged hodographs will support this threat. See SPC Tornado Watch 603 and related mesoscale discussions for the latest near-term guidance on tornado potential. Refer to NHC advisories for the latest track/intensity guidance for Debby, as well as tropical watches/warnings. ..Edwards.. 08/06/2024 Read more

MD 1840 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR SOUTHERN LOWER MI INTO EXTREME NORTHERN IN/NORTHWEST OH
Mesoscale Discussion 1840 NWS Storm Prediction Center Norman OK 0631 AM CDT Tue Aug 06 2024 Areas affected...Southern lower MI into extreme northern IN/northwest OH Concerning...Severe potential...Watch possible Valid 061131Z - 061330Z Probability of Watch Issuance...40 percent SUMMARY...The severe-thunderstorm threat may increase with time this morning. DISCUSSION...A long-lived storm cluster that produced a couple of small bowing segments earlier this morning has evolved into a pair of semi-discrete storms over southern Lake Michigan, with some midlevel rotation and supercell characteristics noted over the last 30-60 minutes. Persistent low-level warm advection and ascent attendant to the convectively enhanced shortwave trough moving across the Great Lakes will support maintenance of these storms through the morning. MUCAPE of 500-1000 J/kg and favorable effective shear (generally greater than 40 kt) will continue to support organized storm structures. The ongoing storms are likely somewhat elevated, which renders the short-term severe threat uncertain. Locally damaging gusts could accompany these storms as they move into southwest lower MI, along with some nonzero hail potential. With favorable low-level shear/SRH in place, a brief tornado cannot be ruled out later this morning along the southern portion of the storm cluster, especially if any notable diurnal heating/destabilization can occur near an outflow-reinforced front. While the short-term threat may remain rather marginal and isolated, watch issuance will become possible if any uptick in storm organization and intensity is noted through mid morning. ..Dean/Edwards.. 08/06/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CLE...DTX...IWX...GRR... LAT...LON 42788621 42628367 42578277 42138300 41538333 41188353 41198409 41268463 41448560 41758651 42788621 Read more

MD 1841 CONCERNING TORNADO WATCH 603... FOR PARTS OF COASTAL SC/NC
Mesoscale Discussion 1841 NWS Storm Prediction Center Norman OK 0757 AM CDT Tue Aug 06 2024 Areas affected...Parts of coastal SC/NC Concerning...Tornado Watch 603... Valid 061257Z - 061430Z The severe weather threat for Tornado Watch 603 continues. SUMMARY...Some tornado threat will persist through the morning. DISCUSSION...Early visible satellite imagery depicts widespread cloudiness across coastal SC/NC, which will tend to inhibit destabilization through the morning. However, dewpoints in the mid/upper 70s F across near-coastal areas will continue to support MLCAPE of around 500 J/kg (as noted on the 12Z MHX sounding). This will be sufficient for maintenance of at least transient small supercell structures, given the presence of 0-1 km SRH of 150-250 m2/s2 in the northeast quadrant of Tropical Storm Debby. The stronger wind field will gradually spread northeastward through the day, and some tornado threat may eventually spread out of WW 603 into a larger part of eastern NC, where somewhat stronger heating may occur through the morning. Eventual watch issuance north of WW 603 is possible if observational trends warrant. ..Dean/Edwards.. 08/06/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MHX...RAH...ILM...CHS...CAE... LAT...LON 33107899 32537993 32698028 33218065 33558015 34577838 34947749 34747690 34527698 34177733 33347866 33107899 Read more

WW 0604 Status Updates
STATUS REPORT ON WW 604 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..DEAN..08/06/24 ATTN...WFO...IWX...GRR...DTX...CLE... STATUS REPORT FOR WT 604 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS INC151-061340- IN . INDIANA COUNTIES INCLUDED ARE STEUBEN MIC023-025-027-059-075-077-091-115-149-061340- MI . MICHIGAN COUNTIES INCLUDED ARE BRANCH CALHOUN CASS HILLSDALE JACKSON KALAMAZOO LENAWEE MONROE ST. JOSEPH OHC051-069-095-123-143-147-171-173-061340- OH . OHIO COUNTIES INCLUDED ARE FULTON HENRY LUCAS OTTAWA SANDUSKY SENECA WILLIAMS WOOD Read more

WW 0603 Status Updates
STATUS REPORT ON WW 603 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..DEAN..08/06/24 ATTN...WFO...ILM...CHS... STATUS REPORT FOR WT 603 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NCC017-019-047-129-141-061340- NC . NORTH CAROLINA COUNTIES INCLUDED ARE BLADEN BRUNSWICK COLUMBUS NEW HANOVER PENDER SCC015-019-035-041-043-051-067-089-061340- SC . SOUTH CAROLINA COUNTIES INCLUDED ARE BERKELEY CHARLESTON DORCHESTER FLORENCE GEORGETOWN HORRY MARION WILLIAMSBURG AMZ250-252-254-256-270-272-274-276-330-350-370-061340- CW . ADJACENT COASTAL WATERS INCLUDED ARE COASTAL WATERS FROM SURF CITY TO CAPE FEAR NC OUT 20 NM Read more

WW 0603 Status Updates
STATUS REPORT ON WW 603 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..DEAN..08/06/24 ATTN...WFO...ILM...CHS... STATUS REPORT FOR WT 603 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NCC017-019-047-129-141-061340- NC . NORTH CAROLINA COUNTIES INCLUDED ARE BLADEN BRUNSWICK COLUMBUS NEW HANOVER PENDER SCC015-019-035-041-043-051-067-089-061340- SC . SOUTH CAROLINA COUNTIES INCLUDED ARE BERKELEY CHARLESTON DORCHESTER FLORENCE GEORGETOWN HORRY MARION WILLIAMSBURG AMZ250-252-254-256-270-272-274-276-330-350-370-061340- CW . ADJACENT COASTAL WATERS INCLUDED ARE COASTAL WATERS FROM SURF CITY TO CAPE FEAR NC OUT 20 NM Read more

WW 603 TORNADO NC SC CW 061055Z - 062100Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 603 NWS Storm Prediction Center Norman OK 655 AM EDT Tue Aug 6 2024 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Southeastern North Carolina Eastern South Carolina Coastal Waters * Effective this Tuesday morning and afternoon from 655 AM until 500 PM EDT. * Primary threats include... A few tornadoes possible SUMMARY...As T.S. Debby moves slowly northeastward (per NHC forecasts), the threat for a few tornadoes should persist and shift across the watch area into more of eastern SC and adjoining coastal NC. Instability will be greatest near the coast, supporting occasional supercells with a tornado threat. The tornado watch area is approximately along and 30 statute miles either side of a line from 25 miles west of Charleston SC to 70 miles northeast of Myrtle Beach SC. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU3). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && OTHER WATCH INFORMATION...This tornado watch replaces tornado watch number 602. Watch number 602 will not be in effect after 655 AM EDT. AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 0.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 13035. ...Edwards Read more

MD 1839 CONCERNING TORNADO WATCH 602... FOR COASTAL SC
Mesoscale Discussion 1839 NWS Storm Prediction Center Norman OK 0341 AM CDT Tue Aug 06 2024 Areas affected...coastal SC Concerning...Tornado Watch 602... Valid 060841Z - 061015Z The severe weather threat for Tornado Watch 602 continues. SUMMARY...A couple tornadoes remain possible early this morning in association with Tropical Storm Debby. DISCUSSION...To the northeast of the center of Tropical Storm Debby, small rotating cells have been noted early this morning within multiple bands of convection. A possible tornado was reported across Berkeley County, SC shortly before 07 UTC, within the outermost band of convection, with other briefly rotating cells noted within an inner band to the west/southwest of Charleston. The KCLX continues to indicate 0-1 km SRH of around 150-200 m2/s2, sufficient for at least transient low-level circulations. Weak instability will continue to be a limiting factor farther inland, but MLCAPE of around 500 J/kg will persist closer to the coast, where temperatures and dewpoints are in the mid/upper 70s F. Some tornado threat may gradually expand northeastward with time, in concert with Debby's slow forward motion. ..Dean.. 08/06/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILM...CHS... LAT...LON 32498099 32948094 33647933 33607899 33347879 33037906 32887937 32607980 32478009 32288037 32118072 32498099 Read more

WW 0602 Status Updates
STATUS REPORT ON WW 602 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1839 ..DEAN..08/06/24 ATTN...WFO...CHS...ILM... STATUS REPORT FOR WT 602 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS SCC013-015-019-029-035-043-053-061040- SC . SOUTH CAROLINA COUNTIES INCLUDED ARE BEAUFORT BERKELEY CHARLESTON COLLETON DORCHESTER GEORGETOWN JASPER AMZ256-276-330-350-352-370-372-061040- CW . ADJACENT COASTAL WATERS INCLUDED ARE COASTAL WATERS FROM MURRELLS INLET TO SOUTH SANTEE RIVER SC OUT 20 NM WATERS FROM MURRELLS INLET NC TO SOUTH SANTEE RIVER SC FROM 20 TO 40 NM CHARLESTON HARBOR Read more

WW 0602 Status Updates
STATUS REPORT ON WW 602 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1839 ..DEAN..08/06/24 ATTN...WFO...CHS...ILM... STATUS REPORT FOR WT 602 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS SCC013-015-019-029-035-043-053-061040- SC . SOUTH CAROLINA COUNTIES INCLUDED ARE BEAUFORT BERKELEY CHARLESTON COLLETON DORCHESTER GEORGETOWN JASPER AMZ256-276-330-350-352-370-372-061040- CW . ADJACENT COASTAL WATERS INCLUDED ARE COASTAL WATERS FROM MURRELLS INLET TO SOUTH SANTEE RIVER SC OUT 20 NM WATERS FROM MURRELLS INLET NC TO SOUTH SANTEE RIVER SC FROM 20 TO 40 NM CHARLESTON HARBOR Read more

WW 602 TORNADO SC CW 060445Z - 061100Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 602 NWS Storm Prediction Center Norman OK 1245 AM EDT Tue Aug 6 2024 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Coastal South Carolina Coastal Waters * Effective this Tuesday morning from 1245 AM until 700 AM EDT. * Primary threats include... A couple tornadoes possible SUMMARY...Convective bands associated with Debby will continue to foster storms moving inland from the coastal waters. Stronger embedded mini supercells within the convective bands will yield an attendant tornado risk near the coast through much of the overnight and into the early morning. The tornado watch area is approximately along and 40 statute miles north and south of a line from 85 miles southwest of Charleston SC to 60 miles east northeast of Charleston SC. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU2). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && OTHER WATCH INFORMATION...CONTINUE...WW 599...WW 600...WW 601... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 0 inches. Extreme turbulence and surface wind gusts to 50 knots. A few cumulonimbi with maximum tops to 400. Mean storm motion vector 15030. ...Smith Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Tue Aug 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... Medium-range guidance indicates that a significant mid-level trough and embedded cyclonic circulation, evolving near the Upper Midwest/Great Lakes region by the beginning of the period, will progress eastward across much of the Northeast by late this weekend. As this occurs, it appears that the remnants of Debby will accelerate into and northeast of the northern Mid Atlantic region on Saturday. Although the degree of interaction between these features remains unclear, significant strengthening of southerly lower/mid-tropospheric flow appears possible within a plume of tropical moisture advecting northward in advance of deepening surface troughing, across the northern Mid Atlantic and Hudson/Champlain Valleys through New England Saturday through Saturday night. Warm mid-levels likely will limit deep-layer instability; but low-level buoyancy, forcing for ascent and shear might become conducive to organizing low-topped convection. In the presence of mean cloud-bearing layer flow possibly on the order of 40-50+ kt, and boundary-layer dew points in the lower/mid 70s, damaging wind gusts and perhaps a few tornadoes will be possible if this scenario unfolds. Due to lingering uncertainties, severe probabilities are being maintained at less than 15 percent. But this could change in later outlooks for this coming Saturday. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Tue Aug 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... Medium-range guidance indicates that a significant mid-level trough and embedded cyclonic circulation, evolving near the Upper Midwest/Great Lakes region by the beginning of the period, will progress eastward across much of the Northeast by late this weekend. As this occurs, it appears that the remnants of Debby will accelerate into and northeast of the northern Mid Atlantic region on Saturday. Although the degree of interaction between these features remains unclear, significant strengthening of southerly lower/mid-tropospheric flow appears possible within a plume of tropical moisture advecting northward in advance of deepening surface troughing, across the northern Mid Atlantic and Hudson/Champlain Valleys through New England Saturday through Saturday night. Warm mid-levels likely will limit deep-layer instability; but low-level buoyancy, forcing for ascent and shear might become conducive to organizing low-topped convection. In the presence of mean cloud-bearing layer flow possibly on the order of 40-50+ kt, and boundary-layer dew points in the lower/mid 70s, damaging wind gusts and perhaps a few tornadoes will be possible if this scenario unfolds. Due to lingering uncertainties, severe probabilities are being maintained at less than 15 percent. But this could change in later outlooks for this coming Saturday. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Tue Aug 06 2024 Valid 081200Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THURSDAY ACROSS PARTS OF EASTERN NORTH CAROLINA AND SOUTHEASTERN VIRGINIA... ...SUMMARY... Showers and thunderstorms developing across the coastal plain of eastern North Carolina through southeastern Virginia may be accompanied by potential for a few tornadoes, as Debby moves inland across the south Atlantic coast Thursday. ...Synopsis... Between one prominent mid-level ridge slowly shifting across and east of the Canadian Northwest Territories and another across much of the Southwest into southern Great Plains, mid-level troughing will be maintained along the western and central Canadian/U.S. border vicinity. Within the latter regime, models suggest that a couple of notable perturbations may consolidate near and northwest of the Upper Midwest/Great Lakes vicinity, where a significant low may begin to evolve by Thursday night. At the same time, although some model output still various considerably from others, it appears most probable that the remnant tropical cyclone, approaching the South Carolina coast at the outset of the period, will continue a slow, generally northerly inland progression across the Carolinas. In response to these developments, further low-level cooling and/or drying is likely over much of the interior U.S. during this period, as surface ridging builds southward to the lee of the northern Rockies, through much of the Missouri and Mississippi Valleys. ...Southern Mid Atlantic... Based on the official forecast track and intensity of Debby, which is still expected to be at tropical storm intensity as it migrates inland across eastern South Carolina, it appears that low-level shear will become at least conditionally supportive of convection capable of producing tornadoes in a sector to the north-northeast of the low-level circulation center. Although the degree of boundary-layer destabilization inland of coastal areas remains uncertain, it appears that appreciable low-level buoyancy may develop where surface dew points increase through the mid 70s F+ in advance of the mid-level warm core. It seems possible that this could overspread much of the eastern North Carolina into southeastern Virginia coastal plain during the day Thursday, when daytime heating will maximize potential instability. ..Kerr.. 08/06/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0154 AM CDT Tue Aug 06 2024 Valid 071200Z - 081200Z ...Synopsis... ...Isolated Dry Thunderstorms... Isolated dry thunderstorms will continue across portions of southern Utah, northwestern Colorado, and south-central Wyoming. A plume of mainly mid-level moisture, with precipitable water values around 0.50-0.75, will support high-based convection with little measurable rainfall, amid receptive fuels. Gusty and erratic outflow winds will be possible near thunderstorms. ...Wind/Dry... Enhanced mid-level westerly flow will remain over the Snake River Plain on Wednesday. Deeply mixed profiles will support downward mixing of flow aloft and sustained surface winds 15-20 mph. This will overlap with relative humidity reductions to 10-15 percent and receptive fuels supporting inclusion of an Elevated risk area. ..Thornton.. 08/06/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more