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MD 1972 CONCERNING SEVERE THUNDERSTORM WATCH 636... FOR SOUTHWESTERN KANSAS...THE OKLAHOMA AND NORTHERN TEXAS PANHANDLE VICINITY
Mesoscale Discussion 1972 NWS Storm Prediction Center Norman OK 0519 PM CDT Sat Aug 12 2023 Areas affected...southwestern Kansas...the Oklahoma and northern Texas Panhandle vicinity Concerning...Severe Thunderstorm Watch 636... Valid 122219Z - 122315Z The severe weather threat for Severe Thunderstorm Watch 636 continues. SUMMARY...An evolving cluster of thunderstorms may continue to slowly organize and become accompanied by increasing potential to produce strong to severe wind gusts across and northeast of the Liberal KS vicinity through 7-9 PM CDT. DISCUSSION...Strongest convection has gradually consolidated near the western Oklahoma Panhandle vicinity, perhaps aided by forcing for ascent within a zone of enhanced lower/mid-tropospheric warm advection, downstream of a weak upper impulse turning northeastward across the southern Rockies. Modest easterly to northeasterly near surface inflow of moist air characterized by mixed-layer CAPE on the order of 2000+ J/kg may maintain vigorous convective development during the next few hours, and it appears possible that an MCV may gradually form as activity propagates northeastward. As it does, strengthening rear inflow to its south through southeast may gradually be accompanied by increasing potential for strong to severe surface gusts by early evening. ..Kerr.. 08/12/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OUN...DDC...AMA...PUB... LAT...LON 36920195 37490234 37850038 36959951 36310003 36140169 36920195 Read more

MD 1971 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTH-CENTRAL GA...INTO PORTIONS OF SOUTHEAST AL
Mesoscale Discussion 1971 NWS Storm Prediction Center Norman OK 0513 PM CDT Sat Aug 12 2023 Areas affected...south-central GA...into portions of southeast AL Concerning...Severe potential...Watch unlikely Valid 122213Z - 130015Z Probability of Watch Issuance...20 percent SUMMARY...Scattered storms may pose an isolated risk for damaging gusts through this evening. DISCUSSION...Over the last hour, scattered thunderstorms across parts of central GA and eastern AL have shown occasional intensification and the potential for isolated damaging gusts. Ongoing within a strongly unstable (3000-4000 J/kg), but weakly sheared environment, storms are excepted to remain predominately multi-cellular. With less than 20 kt of deep-layer shear evident on the FFC VAD, storm organization potential does not appear high. Upscale growth doesn't appear overly likely either, given the weak background and surface flow. Thus, the severe wind risk should be tied to occasional downdraft pulses within the strongest of the ongoing multi-cell clusters. Driven by the buoyancy, isolated damaging gusts will remain possible through this evening as storm slowly propagate south by southeast. The severe risk should gradually diminish after sunset with the onset of nocturnal stabilization. ..Lyons/Thompson.. 08/12/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CAE...FFC...TAE...BMX... LAT...LON 33808304 33888274 33808261 33328225 32928228 32608233 32278252 31968279 31748305 31518348 30978444 30828505 30878515 30938543 31158561 31828570 32318558 32958480 33188436 33388404 33638350 33808304 Read more

WW 0638 Status Updates
STATUS FOR WATCH 0638 HAS NOT BEEN ISSUED YET Read more

WW 638 SEVERE TSTM CT NJ NY PA CW 122210Z - 130400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 638 NWS Storm Prediction Center Norman OK 610 PM EDT Sat Aug 12 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Western Connecticut Northern New Jersey Southeast New York East central Pennsylvania Coastal Waters * Effective this Saturday night from 610 PM until Midnight EDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Scattered large hail events to 1.5 inches in diameter possible A tornado or two possible SUMMARY...Scattered thunderstorms will persist through the evening, some of which will be supercells capable of producing occasional large hail and wind damage. Additional storms will spread into the area late this evening and early tonight, with a continued severe threat. An isolated tornado or two could also occur with favorable storm interactions. The severe thunderstorm watch area is approximately along and 50 statute miles east and west of a line from 55 miles north of Poughkeepsie NY to 35 miles west southwest of Newark NJ. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU8). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for 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. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 633...WW 634...WW 635...WW 636...WW 637... AVIATION...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 28025. ...Thompson Read more

WW 0637 Status Updates
STATUS REPORT ON WW 637 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1968 ..WEINMAN..08/12/23 ATTN...WFO...UNR... STATUS REPORT FOR WS 637 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS SDC007-033-055-071-093-102-103-122240- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE BENNETT CUSTER HAAKON JACKSON MEADE OGLALA LAKOTA PENNINGTON THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 637 SEVERE TSTM SD 122040Z - 130300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 637 NWS Storm Prediction Center Norman OK 240 PM MDT Sat Aug 12 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Western South Dakota * Effective this Saturday afternoon and evening from 240 PM until 900 PM MDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Scattered large hail events to 1.5 inches in diameter possible SUMMARY...Initially isolated thunderstorms near the Black Hills will gradually increase in coverage this evening as the storms develop eastward east of the Black Hills. Large hail will be possible with supercells through this evening. The risk for severe gusts will probably increase once storm coverage increases. The severe thunderstorm watch area is approximately along and 55 statute miles east and west of a line from 45 miles north northeast of Rapid City SD to 80 miles south southwest of Philip SD. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for 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. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 633...WW 634...WW 635...WW 636... AVIATION...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 29025. ...Smith Read more

MD 1970 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PARTS OF EASTERN PA...NORTHERN NJ AND FAR SOUTHERN NY STATE
Mesoscale Discussion 1970 NWS Storm Prediction Center Norman OK 0438 PM CDT Sat Aug 12 2023 Areas affected...parts of eastern PA...northern NJ and far southern NY State Concerning...Severe potential...Watch possible Valid 122138Z - 122345Z Probability of Watch Issuance...40 percent SUMMARY...Isolated severe storms with the potential for damaging gusts, hail and perhaps a tornado are possible this afternoon through the early evening. Uncertainty on the severe risk is high, but a weather watch is being considered. DISCUSSION...As of 2130 UTC, regional radar analysis showed isolated thunderstorms ongoing across parts of far eastern PA, NJ and southern NY State. Thus far, these storms have remained isolated in coverage ahead of a large cluster of more robust storms over western PA and northeast OH. Despite limited synoptic forcing for ascent from the lagging upper trough, the environment ahead of these isolated storms appears favorable to support some risk for severe weather this evening. Surface temps in the low to mid 80s are supporting ~1500 J/kg of MLCAPE with area VADs showing 40-50 kt of effective shear. With a CAPE/shear parameter space favorable for supercells, damaging gusts, hail and perhaps a brief tornado appear possible if storms are able to maintain intensity. The primary uncertainty with regards to the severe threat is the expected storm coverage. Broad-scale ascent is weak and thus far storms have been only marginally organized, likely from lingering inhibition evident on the 20z ALY sounding. However, recent HRRR runs suggests additional storm development/organization is possible through the early evening with a focus across far southern NY state into portions of northern NJ and far eastern PA. While confidence in storm evolution and the severe threat is low, conditions will be monitored for a possible watch. ..Lyons/Thompson.. 08/12/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OKX...ALY...PHI...BGM...CTP...LWX... LAT...LON 40177641 40687634 41157528 41377481 41857451 42157433 42287362 42077335 41707327 41227345 40827370 40397411 39927446 39657481 39507502 39467533 39527569 39627604 39677617 40177641 Read more

WW 0636 Status Updates
STATUS REPORT ON WW 636 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..WEINMAN..08/12/23 ATTN...WFO...PUB...DDC...ABQ...AMA... STATUS REPORT FOR WS 636 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC009-011-099-122240- CO . COLORADO COUNTIES INCLUDED ARE BACA BENT PROWERS KSC025-055-057-067-069-075-081-083-093-119-129-175-187-189- 122240- KS . KANSAS COUNTIES INCLUDED ARE CLARK FINNEY FORD GRANT GRAY HAMILTON HASKELL HODGEMAN KEARNY MEADE MORTON SEWARD STANTON STEVENS NMC059-122240- NM . NEW MEXICO COUNTIES INCLUDED ARE Read more

WW 636 SEVERE TSTM CO KS NM OK TX 122005Z - 130300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 636 NWS Storm Prediction Center Norman OK 305 PM CDT Sat Aug 12 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southeast Colorado Southwest Kansas Far northeast New Mexico Oklahoma Panhandle Texas Panhandle * Effective this Saturday afternoon and evening from 305 PM until 1000 PM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph likely Scattered large hail events to 1.5 inches in diameter possible SUMMARY...Scattered to numerous thunderstorms are forecast to develop and consolidate into a thunderstorm cluster moving generally west to east across the watch area. Severe gusts will be the primary threat with the stronger thunderstorm outflow. Large hail may accompany the stronger thunderstorm cores. The severe thunderstorm watch area is approximately along and 90 statute miles north and south of a line from 40 miles northwest of Clayton NM to 50 miles east southeast of Liberal KS. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU6). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for 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. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 633...WW 634...WW 635... AVIATION...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 25020. ...Smith Read more

WW 0635 Status Updates
STATUS REPORT ON WW 635 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 NE RMG TO 35 SW AVL TO 15 NNE TRI. ..WEINMAN..08/12/23 ATTN...WFO...FFC...GSP...RNK...MRX... STATUS REPORT FOR WS 635 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS GAC011-015-057-085-105-117-119-137-139-147-187-227-241-257-281- 291-311-122240- GA . GEORGIA COUNTIES INCLUDED ARE BANKS BARTOW CHEROKEE DAWSON ELBERT FORSYTH FRANKLIN HABERSHAM HALL HART LUMPKIN PICKENS RABUN STEPHENS TOWNS UNION WHITE NCC003-009-011-021-023-027-035-045-071-089-109-111-115-121-149- 161-175-189-199-122240- NC . NORTH CAROLINA COUNTIES INCLUDED ARE ALEXANDER ASHE AVERY BUNCOMBE BURKE CALDWELL CATAWBA CLEVELAND GASTON HENDERSON LINCOLN MCDOWELL MADISON MITCHELL POLK Read more

WW 635 SEVERE TSTM GA NC SC TN 121840Z - 130000Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 635 NWS Storm Prediction Center Norman OK 240 PM EDT Sat Aug 12 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northern Georgia Western North Carolina Upstate of South Carolina Eastern Tennessee * Effective this Saturday afternoon and evening from 240 PM until 800 PM EDT. * Primary threats include... Scattered damaging wind gusts to 65 mph possible Isolated large hail events to 1 inch in diameter possible SUMMARY...A well-developed thunderstorm cluster moving east across the middle and eastern portions of Tennessee will continue into the southern Appalachians this afternoon. Damaging gusts will be the primary hazard with the stronger cores through the early evening. The severe thunderstorm watch area is approximately along and 65 statute miles east and west of a line from 5 miles north northwest of Bristol TN to 60 miles west southwest of Anderson SC. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for 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. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 633...WW 634... AVIATION...A few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 55 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 27035. ...Smith Read more

WW 0634 Status Updates
STATUS REPORT ON WW 634 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 5 ENE FDY TO 55 NNE CLE. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1969 ..WEINMAN..08/12/23 ATTN...WFO...BUF...BGM...CLE...PBZ...ILN...CTP... STATUS REPORT FOR WT 634 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NYC003-007-009-011-013-015-017-023-025-051-053-065-067-069-075- 077-097-099-101-105-107-109-117-123-122240- NY . NEW YORK COUNTIES INCLUDED ARE ALLEGANY BROOME CATTARAUGUS CAYUGA CHAUTAUQUA CHEMUNG CHENANGO CORTLAND DELAWARE LIVINGSTON MADISON ONEIDA ONONDAGA ONTARIO OSWEGO OTSEGO SCHUYLER SENECA STEUBEN SULLIVAN TIOGA TOMPKINS WAYNE YATES OHC005-007-013-019-029-031-033-035-041-043-055-059-063-065-067- 075-077-081-083-085-089-091-093-099-101-103-111-117-119-121-133- 139-143-147-151-153-155-157-159-169-175-122240- OH . OHIO COUNTIES INCLUDED ARE Read more

WW 634 TORNADO NY OH PA WV LE 121650Z - 130100Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 634 NWS Storm Prediction Center Norman OK 1250 PM EDT Sat Aug 12 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Southern and central New York Northern and eastern Ohio Western and northern Pennsylvania West Virginia Panhandle Lake Erie * Effective this Saturday afternoon and evening from 1250 PM until 900 PM EDT. * Primary threats include... A couple tornadoes possible Scattered damaging wind gusts to 70 mph likely Scattered large hail and isolated very large hail events to 2.5 inches in diameter possible SUMMARY...Scattered to numerous strong to severe thunderstorms are forecast to develop this afternoon and persist into this evening as this activity moves generally west to east across the watch area. The stronger storms are expected to become supercellular and pose a large to very large hail threat, but also some tornado risk. The tornado watch area is approximately along and 70 statute miles north and south of a line from 50 miles south southeast of Utica NY to 45 miles northwest of Columbus 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 633... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 2.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 27030. ...Smith Read more

WW 0633 Status Updates
STATUS REPORT ON WW 633 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 ESE TUP TO 15 E GAD TO 55 S TYS. ..WEINMAN..08/12/23 ATTN...WFO...BMX...HUN...FFC...MRX...OHX... STATUS REPORT FOR WS 633 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC007-009-015-017-019-021-027-029-037-055-057-073-075-093-107- 111-115-117-121-123-125-127-133-122240- AL . ALABAMA COUNTIES INCLUDED ARE BIBB BLOUNT CALHOUN CHAMBERS CHEROKEE CHILTON CLAY CLEBURNE COOSA ETOWAH FAYETTE JEFFERSON LAMAR MARION PICKENS RANDOLPH ST. CLAIR SHELBY TALLADEGA TALLAPOOSA TUSCALOOSA WALKER WINSTON GAC045-115-129-143-233-122240- GA . GEORGIA COUNTIES INCLUDED ARE CARROLL FLOYD GORDON HARALSON POLK Read more

WW 633 SEVERE TSTM AL GA TN 121550Z - 122300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 633 NWS Storm Prediction Center Norman OK 1050 AM CDT Sat Aug 12 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northern Alabama Northwest Georgia Middle into eastern Tennessee * Effective this Saturday morning and evening from 1050 AM until 600 PM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Scattered large hail events to 1.5 inches in diameter possible SUMMARY...A thunderstorm cluster will continue to intensify across the Tennessee Valley into the afternoon as it moves east to east-southeast across the watch area. The stronger storms will be capable of a threat for damaging gusts and perhaps isolated large hail. The severe thunderstorm watch area is approximately along and 95 statute miles east and west of a line from 50 miles north northwest of Crossville TN to 30 miles south southeast of Birmingham AL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU3). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for 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. Severe thunderstorms can and occasionally do produce tornadoes. && AVIATION...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 27035. ...Smith Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0408 PM CDT Sat Aug 12 2023 Valid 141200Z - 201200Z A weak upper level low will continue to drift north and west into next week. This will occur within a dominant upper ridge across the West. The strongest upper-level winds will generally exist along the Canadian border. Later in the week, another trough may approach the Northwest and phase with the weak upper-level low off the western coast. ...Montana... The overall character of the upper-level pattern has continued to vary within guidance over the past day. The GFS has trended away from the ECMWF in terms of the amplitude of the trough digging southward out of the Canadian Prairie early to mid next week. This has resulted in more uncertainty in the timing and magnitude of surface features in the northern Plains vicinity. Even so, the strong upper-level flow remaining along the international border seems probable to promote surface low/trough development that will drive downslope winds in the lee of the northern Rockies. The potential for critical fire weather will exist in parts of western Montana on Wednesday and Thursday. Given the run-to-run variability in guidance, highlights will be withheld this outlook. ...Northern California into the Northwest... The evolution of the upper low will be the main forecast challenge during the period. The feature is forecast to slowly drift north and west. Isolated thunderstorms are possible in parts of northern California beginning on Monday with perhaps some activity lasting into Tuesday as well. Thunderstorms will be possible in Oregon starting Tuesday. Mid-level moisture will also stream northwest with time and allow more convective activity to occur into the middle of the week. Weak disturbances associated with the upper low may also aid in thunderstorm development, but predictability of these features is low. Towards the end of the week, guidance still suggests that cyclonic flow will increase off the Northwest coast. As this occurs, it is likely that the weak low will phase with the approaching trough. There are differences between the GFS and ECMWF, but the general trend has been for the trough to extend farther south than previous runs. This would tend to keep some parts of the Northwest at risk for thunderstorms while also making development in northern California more of a possibility. Some consideration was given to adding isolated dry thunder probabilities to northern California for Monday, but storm motions may be slow enough that more of a mixed wet/dry mode occurs. Storm motions could increase later in the week into the weekend. These time periods will need to be monitored. Confidence in adding highlights still remains low, however, as model variability remains high. In addition to dry thunderstorms, dry and windy conditions may occur as a thermal surface pressure trough develops in the Columbia Basin during most afternoons next week. Elevated conditions will be possible, but the overall lack of synoptic support suggests critical conditions will likely be localized. ...Texas... A cold front should help temperatures moderate early next week. Surface high pressure in the area should also keep winds light. Temperatures will again increase by the end of the week. Conditions will need to be monitored for enough increase in winds to increase fire danger. Furthermore, at least isolated thunderstorms appear possible late next week. ..Wendt.. 08/12/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

5-Day Uncertainty Track last updated Sat, 12 Aug 2023 20:37:23 GMT


Wind Speed Probabilities last updated Sat, 12 Aug 2023 21:22:57 GMT

Issued at 300 PM MDT Sat Aug 12 2023 000 WTPZ42 KNHC 122034 TCDEP2 Tropical Depression Seven-E Discussion Number 1 NWS National Hurricane Center Miami FL EP072023 300 PM MDT Sat Aug 12 2023 Satellite images indicate that the area of low pressure located several hundred miles south-southwest of the southern tip of the Baja California peninsula has attained sufficient organization to be classified as a tropical depression. The last couple of microwave satellite overpasses show a similar scenario, with cold convective curved bands becoming better organized around a low-level center, which appears to be located near the northern edge of the convective cloud mass based on recent visible satellite images. The latest TAFB subjective Dvorak estimate is T-2.0. Based on these data, Invest 98E is upgraded to Tropical Depression Seven-E with an initial intensity of 30 kt. Weak mid-level ridging well to the north of the depression will steer the cyclone toward the west-northwest at about 10 kt over the next few days. Beyond 72 h, the ridge should strengthen enough to cause a turn to the west with a slight increase in forward speed. The NHC forecast track is in best agreement with the HCCA and TVCE consensus models. Environmental conditions are quite favorable for strengthening over the next 48-60 h, with warm ocean temperatures, low vertical wind shear and a relatively moist low to mid-level troposphere. The NHC forecast peaks the system at 75 kt in 48-60 h, which is near the middle of the intensity guidance. The ECMWF version of the SHIPS RI index shows a 52 percent chance of a 65 kt increase in winds over the next 72 h, so there is a chance the cyclone could strengthen more than forecast. After that time, the cyclone is forecast to move into a much drier environment along with slowly decreasing sea-surface temperatures. There is high confidence on significant weakening beyond 72 h due to the very dry airmass that the cyclone will be moving into. FORECAST POSITIONS AND MAX WINDS INIT 12/2100Z 14.9N 113.2W 30 KT 35 MPH 12H 13/0600Z 15.2N 114.2W 40 KT 45 MPH 24H 13/1800Z 15.5N 115.9W 50 KT 60 MPH 36H 14/0600Z 15.7N 117.6W 60 KT 70 MPH 48H 14/1800Z 16.1N 119.2W 75 KT 85 MPH 60H 15/0600Z 16.6N 120.8W 75 KT 85 MPH 72H 15/1800Z 17.1N 122.8W 70 KT 80 MPH 96H 16/1800Z 17.6N 127.7W 50 KT 60 MPH 120H 17/1800Z 17.8N 133.1W 35 KT 40 MPH $$ Forecaster Hagen/Berg

Issued at 2100 UTC SAT AUG 12 2023 943 FOPZ12 KNHC 122033 PWSEP2 TROPICAL DEPRESSION SEVEN-E WIND SPEED PROBABILITIES NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072023 2100 UTC SAT AUG 12 2023 AT 2100Z THE CENTER OF TROPICAL DEPRESSION SEVEN-E WAS LOCATED NEAR LATITUDE 14.9 NORTH...LONGITUDE 113.2 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 30 KTS...35 MPH...55 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 18Z SAT 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 18Z SAT 06Z SUN 18Z SUN 06Z MON 18Z MON 18Z TUE 18Z WED PERIODS TO TO TO TO TO TO TO 06Z SUN 18Z SUN 06Z MON 18Z MON 18Z TUE 18Z WED 18Z THU FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT ISLA CLARION 34 X 3( 3) 3( 6) 2( 8) X( 8) X( 8) X( 8) 15N 115W 34 23 54(77) X(77) 1(78) X(78) X(78) X(78) 15N 115W 50 1 14(15) 1(16) X(16) X(16) X(16) X(16) 15N 115W 64 X 2( 2) X( 2) X( 2) 1( 3) X( 3) X( 3) 20N 115W 34 X 1( 1) 2( 3) 1( 4) X( 4) X( 4) X( 4) 15N 120W 34 X 1( 1) 10(11) 36(47) 12(59) X(59) X(59) 15N 120W 50 X X( X) X( X) 11(11) 9(20) X(20) X(20) 15N 120W 64 X X( X) X( X) 3( 3) 4( 7) X( 7) X( 7) 20N 120W 34 X X( X) 1( 1) 6( 7) 8(15) 1(16) X(16) 15N 125W 34 X X( X) X( X) 1( 1) 10(11) 8(19) X(19) 15N 125W 50 X X( X) X( X) X( X) X( X) 3( 3) X( 3) 20N 125W 34 X X( X) X( X) X( X) 8( 8) 13(21) X(21) 20N 125W 50 X X( X) X( X) X( X) X( X) 4( 4) X( 4) 15N 130W 34 X X( X) X( X) X( X) X( X) 4( 4) 3( 7) 20N 130W 34 X X( X) X( X) X( X) X( X) 6( 6) 6(12) 20N 135W 34 X X( X) X( X) X( X) X( X) X( X) 3( 3) $$ FORECASTER HAGEN/BERG

Issued at 300 PM MDT Sat Aug 12 2023 000 WTPZ32 KNHC 122033 TCPEP2 BULLETIN Tropical Depression Seven-E Advisory Number 1 NWS National Hurricane Center Miami FL EP072023 300 PM MDT Sat Aug 12 2023 ...NEW TROPICAL DEPRESSION FORMS OVER THE OPEN EAST PACIFIC... SUMMARY OF 300 PM MDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...14.9N 113.2W ABOUT 595 MI...955 KM SSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...WNW OR 295 DEGREES AT 10 MPH...17 KM/H MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 300 PM MDT (2100 UTC), the center of Tropical Depression Seven-E was located near latitude 14.9 North, longitude 113.2 West. The depression is moving toward the west-northwest near 10 mph (17 km/h) and this general motion is expected to continue for the next few days. Maximum sustained winds are near 35 mph (55 km/h) with higher gusts. Steady strengthening is expected, and the depression is forecast to become a tropical storm tonight and a hurricane in a couple of days. The estimated minimum central pressure is 1007 mb (29.74 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 900 PM MDT. $$ Forecaster Hagen/Berg