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WW 0539 Status Updates
STATUS REPORT ON WW 539 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 NW GPT TO 30 W MOB TO 20 ENE MOB TO 25 NW PNS TO 15 NNE PNS TO 20 ENE PNS TO 15 WSW PFN TO 25 SSW TLH TO 30 SSE TLH TO 20 W CTY. ..BENTLEY..07/22/23 ATTN...WFO...MOB...TAE...JAX...LIX... STATUS REPORT FOR WS 539 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC003-097-222340- AL . ALABAMA COUNTIES INCLUDED ARE BALDWIN MOBILE FLC033-037-045-067-113-123-222340- FL . FLORIDA COUNTIES INCLUDED ARE ESCAMBIA FRANKLIN GULF LAFAYETTE SANTA ROSA TAYLOR MSC039-047-059-222340- MS . MISSISSIPPI COUNTIES INCLUDED ARE GEORGE HARRISON JACKSON Read more

MD 1681 CONCERNING SEVERE THUNDERSTORM WATCH 540... FOR PORTIONS OF EXTREME EASTERN TEXAS...CENTRAL AND SOUTHERN LOUISIANA INTO SOUTHERN MISSISSIPPI
Mesoscale Discussion 1681 NWS Storm Prediction Center Norman OK 0456 PM CDT Sat Jul 22 2023 Areas affected...portions of extreme eastern Texas...central and southern Louisiana into southern Mississippi Concerning...Severe Thunderstorm Watch 540... Valid 222156Z - 222330Z The severe weather threat for Severe Thunderstorm Watch 540 continues. SUMMARY...The severe threat continues across Severe Thunderstorm Watch 540. Damaging gusts remain the primary threat, though an instance or two of large hail cannot be ruled out. DISCUSSION...Multicellular clusters have organized roughly into two west-east oriented bands of storms over the past couple of hours, with a history of a couple of strong, damaging gusts. MRMS mosaic radar imagery suggest that the cores of the stronger storms are quite deep, with 30 dBZ echoes extending to 60 kft in spots, with 50 dBZ echoes reaching over 35 kft. Though deep-layer shear remains modest, 21Z mesoanalysis depicts over 4000 J/kg MLCAPE residing ahead of these deep cores (driven mainly by rich low-level moisture beneath 6-7 C/km mid-level lapse rates per latest RAP forecast soundings). Furthermore, the RAP forecast soundings show PWATS well over 2 inches given the rich moisture. As such, water-loading within these deep storm cores may promote additional damaging gusts (some potentially exceeding severe limits), and even an instance or two of large hail cannot be completely ruled out. The severe threat should persist through the remainder of the diurnal heating cycle, or when storms overturn all of the boundary layer over land, which ever comes first. ..Squitieri.. 07/22/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MOB...JAN...LIX...LCH...SHV... LAT...LON 31699438 31959182 31989098 31518986 30778923 30308926 29468969 29219049 29329176 29559259 29879362 31699438 Read more

WW 0541 Status Updates
STATUS REPORT ON WW 541 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..BENTLEY..07/22/23 ATTN...WFO...TOP...GLD...DDC...ICT...GID...LBF... STATUS REPORT FOR WS 541 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS KSC027-029-039-041-051-053-061-065-089-105-123-127-137-141-143- 147-153-157-161-163-167-169-179-183-195-201-222240- KS . KANSAS COUNTIES INCLUDED ARE CLAY CLOUD DECATUR DICKINSON ELLIS ELLSWORTH GEARY GRAHAM JEWELL LINCOLN MITCHELL MORRIS NORTON OSBORNE OTTAWA PHILLIPS RAWLINS REPUBLIC RILEY ROOKS RUSSELL SALINE SHERIDAN SMITH TREGO WASHINGTON NEC001-019-029-035-041-047-057-059-061-063-065-073-079-081-083- 085-087-099-101-111-129-135-137-145-169-181-222240- NE . NEBRASKA COUNTIES INCLUDED ARE ADAMS BUFFALO CHASE CLAY CUSTER DAWSON DUNDY FILLMORE FRANKLIN Read more

WW 541 SEVERE TSTM KS NE 222030Z - 230400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 541 NWS Storm Prediction Center Norman OK 330 PM CDT Sat Jul 22 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northern Kansas Southern Nebraska * Effective this Saturday afternoon and evening from 330 PM until 1100 PM CDT. * Primary threats include... Scattered large hail likely with isolated very large hail events to 2.5 inches in diameter possible Scattered damaging wind gusts to 70 mph possible SUMMARY...Widely scattered supercell storms are forming over southern Nebraska. These storms will track southward through the afternoon and early evening, posing a risk of very large hail and damaging winds. The severe thunderstorm watch area is approximately along and 60 statute miles north and south of a line from 30 miles north northwest of Imperial NE to 50 miles east southeast of Concordia KS. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU1). 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 539...WW 540... AVIATION...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 33025. ...Hart Read more

WW 539 SEVERE TSTM AL FL GA MS CW 221645Z - 230000Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 539 NWS Storm Prediction Center Norman OK 1145 AM CDT Sat Jul 22 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southern Alabama Northern Florida including the Panhandle Southern Georgia Southern Mississippi Coastal Waters * Effective this Saturday morning and evening from 1145 AM until 700 PM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Thunderstorms are developing along a boundary sagging southward across the Gulf Coast region. A few of these storms will pose a risk of damaging downburst winds through the afternoon. The severe thunderstorm watch area is approximately along and 45 statute miles north and south of a line from 5 miles northwest of Gulfport MS to 25 miles northeast of Jacksonville FL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU9). 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 29025. ...Hart Read more

WW 0540 Status Updates
STATUS REPORT ON WW 540 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..BENTLEY..07/22/23 ATTN...WFO...LCH...LIX...JAN... STATUS REPORT FOR WS 540 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS LAC001-003-005-007-009-011-019-033-037-039-045-047-053-055-063- 077-079-091-093-095-097-099-103-105-115-117-121-125-222240- LA . LOUISIANA PARISHES INCLUDED ARE ACADIA ALLEN ASCENSION ASSUMPTION AVOYELLES BEAUREGARD CALCASIEU EAST BATON ROUGE EAST FELICIANA EVANGELINE IBERIA IBERVILLE JEFFERSON DAVIS LAFAYETTE LIVINGSTON POINTE COUPEE RAPIDES ST. HELENA ST. JAMES ST. JOHN THE BAPTISTST. LANDRY ST. MARTIN ST. TAMMANY TANGIPAHOA VERNON WASHINGTON WEST BATON ROUGE WEST FELICIANA MSC005-035-045-073-091-109-113-147-157-222240- MS . MISSISSIPPI COUNTIES INCLUDED ARE AMITE FORREST HANCOCK LAMAR MARION PEARL RIVER PIKE WALTHALL WILKINSON Read more

WW 540 SEVERE TSTM LA MS TX CW 221915Z - 230200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 540 NWS Storm Prediction Center Norman OK 215 PM CDT Sat Jul 22 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southern Louisiana Southern Mississippi East Texas Coastal Waters * Effective this Saturday afternoon and evening from 215 PM until 900 PM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Thunderstorms continue to develop along a boundary sagging into southern Louisiana/Mississippi. The strong cells along this line will pose a risk of locally damaging wind gusts. The severe thunderstorm watch area is approximately along and 45 statute miles north and south of a line from 45 miles west southwest of Fort Polk LA to 40 miles east northeast of Slidell LA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). 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 539... 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. ...Hart Read more

MD 1680 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR EASTERN NEW MEXICO AND THE WESTERN TEXAS PANHANDLE INTO SOUTHWEST TEXAS
Mesoscale Discussion 1680 NWS Storm Prediction Center Norman OK 0354 PM CDT Sat Jul 22 2023 Areas affected...Eastern New Mexico and the western Texas Panhandle into Southwest Texas Concerning...Severe potential...Watch unlikely Valid 222054Z - 222300Z Probability of Watch Issuance...20 percent SUMMARY...Scattered storms capable of large hail and strong winds possible late afternoon/early evening. DISCUSSION...Scattered thunderstorm development is expected across eastern New Mexico through the afternoon and early evening, with some uncertainty as to how far into Texas storms will track. Cumulus has increased across northeastern New Mexico with attempts at cell development over the last hour. Additionally, areas of convection ongoing across the high terrain may move into the lower elevations through the afternoon as well. MLCAPE is observed around 1000-2000 J/kg. Shear is largely confined to far northeastern New Mexico into the Texas Panhandle. Given uncertainty in coverage and if storms will track into the best shear/instability overlap, a watch is unlikely at this time. Isolated instances of large hail and gusty winds will be possible. ..Thornton/Hart.. 07/22/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LUB...AMA...MAF...PUB...ABQ... LAT...LON 35200526 35830477 36380435 36850379 37050334 37030272 36700255 36340240 35930238 35510236 35190240 34730240 34110247 33860261 33690278 33570299 33410347 33310398 33680481 34290533 35200526 Read more

Issued at 500 PM AST Sat Jul 22 2023 000 WTNT45 KNHC 222046 TCDAT5 Hurricane Don Discussion Number 35 NWS National Hurricane Center Miami FL AL052023 500 PM AST Sat Jul 22 2023 Don's cloud pattern continued to become better organized after the release of the previous advisory with convection wrapping around an eye in infrared imagery. Since that time, the cloud tops over the western semicircle have warmed somewhat, but a 1648 UTC AMSR2 microwave pass showed a well-defined low- to mid-level eye with deep convection surrounding it. Subjective Dvorak estimates at 1800 UTC ranged from T4.0 (65 kt) from TAFB and T3.5 (55 kt) from SAB, with objective estimates in the 60 to 63 kt range. Since subjective estimates have yielded a T4.0 throughout much of the afternoon, the initial intensity has been raised to 65 kt, making Don a hurricane. Today's strengthening was the result of the storm passing over the warmer waters of the Gulf Stream, however it will move north of those warmer waters later this evening, and Don has likely peaked in intensity. Weakening should begin overnight, with a faster rate of weakening expected Sunday through Monday as Don moves over even colder waters and the vertical wind shear increases. The cyclone is expected to become post-tropical by Sunday night, and dissipate by Monday night or early Tuesday. Don is moving northward or 005 degrees at 10 kt. The cyclone is forecast to turn northeastward late tonight as it becomes embedded within southwesterly flow between a ridge to its east and a broad trough over eastern Canada. A northeastward to east-northeastward motion should then continue until the system dissipates in 2-3 days. The track guidance is again tightly clustered and no significant changes to the previous official forecast were required. FORECAST POSITIONS AND MAX WINDS INIT 22/2100Z 40.1N 50.0W 65 KT 75 MPH 12H 23/0600Z 42.0N 49.6W 60 KT 70 MPH 24H 23/1800Z 44.5N 47.6W 50 KT 60 MPH 36H 24/0600Z 46.4N 44.5W 40 KT 45 MPH...POST-TROPICAL 48H 24/1800Z 47.7N 40.4W 30 KT 35 MPH...POST-TROP/REMNT LOW 60H 25/0600Z...DISSIPATED $$ Forecaster Brown

5-Day Uncertainty Track last updated Sat, 22 Jul 2023 20:45:41 GMT


Wind Speed Probabilities last updated Sat, 22 Jul 2023 21:23:02 GMT

Issued at 2100 UTC SAT JUL 22 2023 000 FONT15 KNHC 222044 PWSAT5 HURRICANE DON WIND SPEED PROBABILITIES NUMBER 35 NWS NATIONAL HURRICANE CENTER MIAMI FL AL052023 2100 UTC SAT JUL 22 2023 AT 2100Z THE CENTER OF HURRICANE DON WAS LOCATED NEAR LATITUDE 40.1 NORTH...LONGITUDE 50.0 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 65 KTS ...75 MPH...120 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) ATLANTIC STANDARD TIME (AST)...SUBTRACT 4 HOURS FROM Z TIME EASTERN DAYLIGHT TIME (EDT)...SUBTRACT 4 HOURS FROM Z TIME CENTRAL DAYLIGHT TIME (CDT)...SUBTRACT 5 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 $$ FORECASTER BROWN

Issued at 500 PM AST Sat Jul 22 2023 000 WTNT35 KNHC 222044 TCPAT5 BULLETIN Hurricane Don Advisory Number 35 NWS National Hurricane Center Miami FL AL052023 500 PM AST Sat Jul 22 2023 ...DON BECOMES A HURRICANE JUST BEFORE REACHING COOLER WATERS... SUMMARY OF 500 PM AST...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...40.1N 50.0W ABOUT 480 MI...775 KM SSE OF CAPE RACE NEWFOUNDLAND MAXIMUM SUSTAINED WINDS...75 MPH...120 KM/H PRESENT MOVEMENT...N OR 5 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...988 MB...29.18 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 500 PM AST (2100 UTC), the center of Hurricane Don was located near latitude 40.1 North, longitude 50.0 West. Don is moving toward the north near 12 mph (19 km/h). A northeastward turn is expected later tonight or early Sunday, and a northeastward to east-northeastward motion should continue until the system dissipates Monday night or early Tuesday. Maximum sustained winds have increased to near 75 mph (120 km/h) with higher gusts. Steady weakening should begin later tonight or early Sunday, and Don is forecast to become a post-tropical cyclone Sunday night. Hurricane-force winds extend outward up to 15 miles (30 km) from the center and tropical-storm-force winds extend outward up to 70 miles (110 km). The estimated minimum central pressure is 988 mb (29.18 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 1100 PM AST. $$ Forecaster Brown

...DON BECOMES A HURRICANE JUST BEFORE REACHING COOLER WATERS... As of 5:00 PM AST Sat Jul 22 the center of Don was located near 40.1, -50.0 with movement N at 12 mph. The minimum central pressure was 988 mb with maximum sustained winds of about 75 mph.

Issued at 2100 UTC SAT JUL 22 2023 000 WTNT25 KNHC 222043 TCMAT5 HURRICANE DON FORECAST/ADVISORY NUMBER 35 NWS NATIONAL HURRICANE CENTER MIAMI FL AL052023 2100 UTC SAT JUL 22 2023 NOTICE... LAND-BASED TROPICAL CYCLONE WATCHES AND WARNINGS ARE NO LONGER INCLUDED IN THE TROPICAL CYCLONE FORECAST/ADVISORY...(TCM). CURRENT LAND-BASED COASTAL WATCHES AND WARNINGS CAN BE FOUND IN THE MOST RECENTLY ISSUED TROPICAL CYCLONE PUBLIC ADVISORY...(TCP). HURRICANE CENTER LOCATED NEAR 40.1N 50.0W AT 22/2100Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE NORTH OR 5 DEGREES AT 10 KT ESTIMATED MINIMUM CENTRAL PRESSURE 988 MB MAX SUSTAINED WINDS 65 KT WITH GUSTS TO 80 KT. 64 KT....... 15NE 0SE 0SW 0NW. 50 KT....... 30NE 20SE 0SW 20NW. 34 KT....... 60NE 50SE 30SW 40NW. 12 FT SEAS.. 90NE 90SE 60SW 90NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 40.1N 50.0W AT 22/2100Z AT 22/1800Z CENTER WAS LOCATED NEAR 39.5N 50.1W FORECAST VALID 23/0600Z 42.0N 49.6W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 20NE 20SE 0SW 20NW. 34 KT... 60NE 70SE 40SW 40NW. FORECAST VALID 23/1800Z 44.5N 47.6W MAX WIND 50 KT...GUSTS 60 KT. 50 KT... 20NE 20SE 0SW 0NW. 34 KT... 60NE 70SE 30SW 30NW. FORECAST VALID 24/0600Z 46.4N 44.5W...POST-TROPICAL MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 40NE 60SE 30SW 0NW. FORECAST VALID 24/1800Z 47.7N 40.4W...POST-TROP/REMNT LOW MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 25/0600Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 40.1N 50.0W NEXT ADVISORY AT 23/0300Z $$ FORECASTER BROWN

MD 1679 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR WESTERN WISCONSIN AND MINNESOTA
Mesoscale Discussion 1679 NWS Storm Prediction Center Norman OK 0336 PM CDT Sat Jul 22 2023 Areas affected...western Wisconsin and Minnesota Concerning...Severe potential...Watch unlikely Valid 222036Z - 222230Z Probability of Watch Issuance...20 percent SUMMARY...Scattered storms capable of large hail may continue through the afternoon. DISCUSSION...Ongoing thunderstorm activity across Minnesota and Wisconsin have produced scattered reports of 0.50"-1.25" hail, along with one report of 2.5 inch hail near Marcell, MN. Convection is further aided by a mid-level impulse digging southward across Minnesota at this time. RAP sounding analysis indicates largely straight hodographs with steep low-level lapse rates and unstable conditions through the profile. MLCAPE around 1500 J/kg overlaps deep layer shear around 30-35 kts. Discrete convection has been able to produce larger hail within this environment. Forcing for ascent remains somewhat weak, though moisture convergence is evident from surface objective analysis and surface observations. Uncertainty if discrete storm mode will continue and duration/coverage of the large hail threat. Instances of sub-severe hail and hail up to 1-1.5 will be possible. Trends will continue to be monitored but a watch is unlikely to be issued at this time. ..Thornton/Hart.. 07/22/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DLH...ARX...MPX...FGF...FSD... LAT...LON 44379096 44239102 43899172 43809258 43729337 43719403 43779495 43829552 43829606 44099621 44419633 45019605 46239555 46859556 47359558 48109504 48059356 47749298 47109277 46479275 46169227 46009175 45689092 45299056 44379096 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Jul 22 2023 Valid 222000Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND SOUTHEAST... ...SUMMARY... Strong to severe thunderstorms capable of large hail and damaging winds remain possible into this evening across parts of the central Plains. Storms capable of isolated damaging gusts may persist into this evening across parts of the Southeast, and develop by early evening over parts of Arizona. ...20Z Update... The Slight Risk has been trimmed slightly across parts of AL/GA, in the immediate wake of storms sagging southward toward the Gulf Coast. The Marginal Risk has been expanded across parts of northern MN, southwest MN into southeast SD, and north-central NE, where developing cumulus and storm initiation has been recently observed within a somewhat favorable (but weakly forced) environment, with hail and localized damaging gusts the primary threats. A small part of the Marginal Risk has been trimmed across far northeast MN/northwest WI, where substantial redevelopment appears likely in the wake of earlier convection. Otherwise, no major changes have been made. Storms capable of locally damaging winds will remain possible through the afternoon across parts of the Southeast, and may develop by early this evening across parts of Arizona. Storms capable of hail and localized severe gusts may increase in coverage late this afternoon and evening across parts of the central Plains, with a more isolated threat into the upper Midwest. See the previous discussion below for more information. See MCD 1677 for more information regarding the threat across parts of the central Plains. ..Dean.. 07/22/2023 .PREV DISCUSSION... /ISSUED 1118 AM CDT Sat Jul 22 2023/ ...KS Vicinity... Morning visible satellite imagery shows clear skies over most of KS, where strong heating will combine with dewpoints in the mid 60s to yield afternoon MLCAPE around 1500 J/kg. Large scale forcing is subtle in this region, with weak mid-level height rises and diffuse surface boundaries expected to influence storm potential. Nevertheless, most 12z CAM solutions continue to show potential for widely scattered thunderstorms by late afternoon. Deep northwest flow aloft will provide sufficient vertical shear for rotating updrafts capable of large hail and damaging wind gusts. ...Gulf Coast Region... A weak surface boundary extends from southern MS eastward into southern GA today. The air mass along and south of the boundary is very moist and unstable. Scattered thunderstorms are expected to affect this region through the afternoon. The southern fringe of stronger mid-level westerlies lies along the boundary, and will likely result in at least isolated instances of damaging wind gusts. Please refer to MCD #1675 for further details. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Sat Jul 22 2023 Valid 231200Z - 241200Z ...Southern California... Updated Hi-res model guidance has trended stronger with the aforementioned shortwave rotating around the west side of the upper-level ridge. Area model soundings show dry low-levels, with deep inverted V structures, and sufficient CAPE for thunderstorms across portions of the southern California mountains and deserts. The stronger shortwave, and presence of increasing monsoon moisture lend higher confidence in dry thunderstorm coverage being slightly higher than previously forecast. Storms are most likely across portions of the High deserts and eastern most Transverse Ranges. More localized storms are possible farther west across the Ventura and Peninsular Ranges, but uncertainty increases toward the coast. With the greater confidence in isolated storm coverage, dry fuels and lightning, an IsoDryT area has been added for portions of southern CA. ...Northern Great Basin into southern/western ID... In addition to gusty winds and lower humidity, isolated thunderstorms are possible across portions of northeastern NV, into far eastern OR and southern ID D2/Sun evening into early D3/Mon. With a deep and dry mixed layer present on area forecast soundings, little wetting rain potential is expected with any storms able to develop. The highest confidence in storm coverage is across portions of eastern ID where less receptive fuels are present. However, very isolated dry storms are possible, with some potential for lightning ignitions within receptive fuels, across portions of far southeast OR and southwestern ID. ..Lyons.. 07/22/2023 .PREV DISCUSSION... /ISSUED 0104 AM CDT Sat Jul 22 2023/ ...Synopsis... The upper-level ridge will start to shift east on Sunday which will allow some stronger mid-level flow to overspread the Northwest and the northern Great Basin. Downslope flow in the lee of the Sierra and deep mixing across northern Nevada/southern Oregon will allow winds to increase to 15 to 20 mph during the afternoon amid single-digit relative humidity. Some enhancement of the flow is possible across southern Nevada on Sunday as a weak mid-level shortwave trough moves northward around the western edge of the anticyclone. This shortwave trough is currently across central New Mexico and may undergo some convective enhancement during the D1/Saturday period. Due to the influence of Day 1 convection on the strength of this trough, will not add an Elevated area at this time. Some elevated conditions are possible in the Snake River Plain on Sunday as stronger mid-level flow overspreads the region and low pressure develops in the northern Great Basin. However, fuels in the area remain only marginally dry. Therefore, an Elevated delineation is not warranted at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Sat Jul 22 2023 Valid 231200Z - 241200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF ARIZONA...AND ALSO ACROSS PARTS OF GEORGIA AND THE CAROLINAS... ...SUMMARY... Thunderstorms with isolated damaging wind will be possible across parts of Georgia and the Carolinas on Sunday. Thunderstorms with isolated severe thunderstorm gusts are also possible mainly Sunday evening over portions of Arizona. ...Synopsis... An upper ridge centered over the Four Corners region is forecast to build into a larger portion of the central/southern Plains on Sunday, as an upper trough over the eastern CONUS gradually weakens and shifts eastward. At the surface, a weakening cold front will likely be draped somewhere from south-central TX northeastward into southern parts of LA/MS/AL, central/southern GA, and the eastern Carolinas. A weak surface low may develop over the northern High Plains and move southeastward along a surface trough. ...Parts of Georgia and the Carolinas... Moderate buoyancy is expected to develop along/ahead of the cold front across parts of the Southeast. The most favorable overlap of instability, stronger flow aloft, and storm coverage is expected from parts of Georgia into the Carolinas, immediately in advance of the main upper trough. Scattered to numerous thunderstorms may develop during the afternoon, with deep-layer shear sufficient for a few modestly organized cells/clusters capable of localized damaging gusts and small to perhaps marginally severe hail. Isolated strong storms may also develop farther west near the southern Appalachians, within a drier but modestly unstable regime. Coverage of the severe threat appears too low for probabilities at this time, but some threat for isolated damaging gusts could evolve in this area as well. ...Arizona... Very strong heating and increasing PW will support isolated to scattered thunderstorm development during the late afternoon near the Mogollon Rim, and potentially into the lower deserts across AZ. Isolated microbursts will be possible with the initial development. 15-20 kt of easterly midlevel flow along the southern periphery of the ridge may support a few outflow-driven, westward-moving clusters capable of at least localized severe gusts into Sunday evening. Some threat could reach as far as the lower CO River Valley before weakening. ...Central/northern Plains into the Midwest... A broad portion of the central/northern Plains and Midwest will reside in a regime characterized by northwesterly mid/upper-level flow, modest low-level moisture, relatively steep low/midlevel lapse rates, and generally weak large-scale ascent. Very isolated storm development will be possible within this regime, with sufficient instability and deep-layer to support a conditional supercell risk. Severe probabilities may eventually be needed for some part of this area, if confidence increases in the location and coverage of potential development. ..Dean.. 07/22/2023 Read more

000
ABNT20 KNHC 221724
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Sat Jul 22 2023

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Don, located over the central Atlantic.

Central Tropical Atlantic (AL95):
Shower activity associated with a small area of low pressure located
roughly midway between the Cabo Verde Islands and the Lesser
Antilles has become a little less organized since yesterday.
Environmental conditions are forecast to remain marginally conducive
for some gradual development, and this system could become a
tropical depression early next week while it moves westward across
the tropical Atlantic. Interests in the Lesser Antilles should
monitor the progress of this system.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 7 days...medium...60 percent.

$$
Forecaster Kelly/Brown

000
ABPZ20 KNHC 221722
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Sat Jul 22 2023

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

Active Systems:
The National Hurricane Center has issued the last advisory on
Post-Tropical Cyclone Four-E, located well west-southwest of the
southern tip of the Baja California peninsula.

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Brown