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WW 585 SEVERE TSTM MO 042215Z - 050400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 585 NWS Storm Prediction Center Norman OK 515 PM CDT Fri Aug 4 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northern and Central Missouri * Effective this Friday afternoon and evening from 515 PM until 1100 PM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph likely Isolated large hail events to 1.5 inches in diameter possible A tornado or two possible SUMMARY...A very warm, moist, and unstable air mass exists across northern and central Missouri this afternoon. Thunderstorms are expected to develop within this environment, with moderate vertical shear helping to organize a few of these storms into supercells. Some large hail and/or damaging gusts are possible with the strongest storms. There is a low chance for a tornado. The severe thunderstorm watch area is approximately along and 60 statute miles north and south of a line from 50 miles northwest of Knob Noster MO to 25 miles east northeast of Columbia MO. 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 584... 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 550. Mean storm motion vector 27035. ...Mosier Read more

MD 1835 CONCERNING SEVERE THUNDERSTORM WATCH 584... FOR EASTERN PENNSYLVANIA INTO THE NEW ENGLAND REGION
Mesoscale Discussion 1835 NWS Storm Prediction Center Norman OK 0513 PM CDT Fri Aug 04 2023 Areas affected...Eastern Pennsylvania into the New England region Concerning...Severe Thunderstorm Watch 584... Valid 042213Z - 050015Z The severe weather threat for Severe Thunderstorm Watch 584 continues. SUMMARY...The severe threat continues across WW 584, and may extend into portions of southern/southeastern Pennsylvania over the next couple of hours. DISCUSSION...Scattered strong to severe thunderstorms continue to develop along the cold frontal boundary draped across the New England region. Recent GOES imagery shows transient nature of some cells, possibly due to undercutting outflow from prior convection, but cooling cloud top temperatures in IR imagery as well as tight clustering of in-cloud lightning with developing storms suggest robust convection remains possible. Recent GOES-derived winds and cloud heights suggest that 40-50 knot anvil-level winds, combined with weaker low-level flow, continue to support nearly 30 knots of deep-layer shear orthogonal to the frontal axis. Given adequate buoyancy over the region, this will maintain the potential for additional discrete convection (including a few supercells) prior to the onset of stronger nocturnal stabilization later this evening. The approach of a 300 mb jet max into the Mid-Atlantic region will augment broad-scale ascent across eastern PA, and may allow for the severe threat to continue towards the MD border. Portions of WW 584 have been extended to address this concern, but further downstream watch issuance is uncertain given a diminishing thermodynamic environment towards the coast and the influence of nocturnal cooling in the coming hours. ..Moore.. 08/04/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GYX...BOX...BTV...OKX...ALY...PHI...BGM...CTP... LWX...PBZ... LAT...LON 40407899 41147793 42727542 44077236 43997176 43797107 43387101 42537170 40797447 39737588 39657664 39667790 39747879 39877906 40117915 40407899 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0503 PM CDT Fri Aug 04 2023 Valid 061200Z - 121200Z ...Central Texas and Southwestern Oklahoma... A cold front will sag southward Sunday and stall near the Red River through late Monday, bringing a shift to northwesterly flow across southwestern Oklahoma/northwestern and north-central Texas. This will also bring a chance for showers and thunderstorms along the front, with low confidence in wetting precipitation outside of southwestern Oklahoma into the Texas Panhandle and areas right along the Red River. Elevated to near critical fire weather will be possible before the passage of the front. However, uncertainty in where sustained winds around 15 mph or greater will be, potential cloud cover and increase in RH behind the front, and how much wetting precipitation will occur limit inclusion of any areas at this time. Lightning strikes may lead to new starts in the absence of wetting rain. The front will lift northward on Monday with warming and drying conditions to return. Across central Texas, continued dry conditions are expected with 100+ F degree temperatures forecast through the extended period. Afternoon relative humidity reductions to around 15-20 percent will be possible each day. Drought stress and extreme heat have led to rapidly drying fuels (with ERCs around the 97th percentile) within this region. Given the very critical nature of fuels, Elevated to Critical fire weather concerns can be expected each afternoon through the extended. Overall, confidence in coverage of sustained 15 mph or greater winds precludes the need to include any Critical probabilities at this time. ...Southwest and Great Basin... Westerly flow further enhanced by strengthening mid-level flow atop the ridge will bring drying conditions across the Southwest. Lingering mid-level moisture will remain south of the Mogollon Rim in Arizona. Fuels within much of the Great Basin and Southwest have seen wetting rainfall from recent monsoonal activity which will limit fire weather concerns. Less rainfall was observed across far northeastern Arizona and northern New Mexico. ERCs within this region are in the 75th-90th percentile. A 40 percent delineation has been maintained on Sunday and Monday to characterize this threat. This threat may continue Tuesday before high pressure builds back in across the four corners with moisture steadily increasing into late in the period. ..Thornton.. 08/04/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 1834 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR WESTERN NE...NORTHEAST CO...NORTHWEST KS
Mesoscale Discussion 1834 NWS Storm Prediction Center Norman OK 0452 PM CDT Fri Aug 04 2023 Areas affected...Western NE...Northeast CO...Northwest KS Concerning...Severe potential...Watch possible Valid 042152Z - 042315Z Probability of Watch Issuance...40 percent SUMMARY...The threat for hail and localized severe gusts may increase into this evening. Watch issuance is possible. DISCUSSION...Storms are gradually increasing in coverage and intensity late this afternoon from northeast CO into western NE, to the south of a upper-level cyclone over the northern High Plains. A surface low is located near over far southeast MT, with a surface trough extending southeastward toward the NE Sandhills region, and then southwestward toward the NE Panhandle. A secondary low-level confluence zone is noted over northeast CO. Storms will likely continue to increase near these surface features and spread eastward into this evening. Moderate buoyancy and modest effective shear (generally 25-35 kt) will support a mix of strong multicells and perhaps a marginal supercell or two, with an initial threat of isolated hail and severe gusts. An outflow-driven cluster may eventually evolve and move somewhere across northern KS/southern NE later this evening, with at least an isolated severe-wind threat. While the environment is not particularly favorable for longer-lived supercells or a well-organized MCS, watch issuance is possible given the potential for increasing coverage of storms with at least some severe hail/wind threat into this evening. ..Dean/Mosier.. 08/04/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GID...LBF...GLD...BOU...CYS... LAT...LON 41230285 42220161 42550102 42860046 42619993 42119972 40889983 40020039 39140135 38870153 38670241 39000344 41230285 Read more

5-Day Uncertainty Track last updated Fri, 04 Aug 2023 20:37:26 GMT


Wind Speed Probabilities last updated Fri, 04 Aug 2023 21:23:10 GMT

Issued at 1100 AM HST Fri Aug 04 2023 000 WTPZ45 KNHC 042035 TCDEP5 Hurricane Dora Discussion Number 17 NWS National Hurricane Center Miami FL EP052023 1100 AM HST Fri Aug 04 2023 While there are occasional hints of an eye in visible and infrared satellite imagery, the organization of Dora has decreased a little since the last advisory. This is most notable in the eastern semicircle, where the size of the central dense overcast has diminished due to the effects of easterly shear. Satellite intensity estimates are now in the 90-105 kt range, and the initial intensity is reduced to a somewhat uncertain 95 kt. This is starting to sound like a stuck record, but the initial motion is again 265/16 kt. The track guidance and the track forecast philosophy are again unchanged from the previous advisory, as a deep-layer ridge to the north of the storm is forecast to build westward and keep Dora on the same general trajectory for entire forecast period. The new forecast track has noise-level adjustments from the previous track. The current shear should let up in the next 12-18 h, but until that time Dora should continue to weaken some. After 18 h, the cyclone should be over 26-27C sea surface temperatures, with the forecast track taking Dora close to a patch of colder water between 72-96 h. Based on these conditions and the intensity guidance, the new intensity forecast calls for a little more weakening during the first 24 h, followed by little change in strength from 24-72 h. After 72 h, slight weakening is forecast due to the colder water just to the north of the track. The new forecast is near the intensity consensus through 72 h, then lies a little above the consensus. It should be noted, though, that even while weakening Dora is expected to remain a hurricane through the entire 5-day forecast period. FORECAST POSITIONS AND MAX WINDS INIT 04/2100Z 13.8N 128.5W 95 KT 110 MPH 12H 05/0600Z 13.6N 130.8W 90 KT 105 MPH 24H 05/1800Z 13.5N 134.0W 85 KT 100 MPH 36H 06/0600Z 13.3N 137.5W 85 KT 100 MPH 48H 06/1800Z 13.1N 141.0W 85 KT 100 MPH 60H 07/0600Z 12.9N 144.6W 85 KT 100 MPH 72H 07/1800Z 12.8N 148.4W 85 KT 100 MPH 96H 08/1800Z 12.5N 156.5W 80 KT 90 MPH 120H 09/1800Z 13.0N 164.0W 75 KT 85 MPH $$ Forecaster Beven

Issued at 2100 UTC FRI AUG 04 2023 000 FOPZ15 KNHC 042035 PWSEP5 HURRICANE DORA WIND SPEED PROBABILITIES NUMBER 17 NWS NATIONAL HURRICANE CENTER MIAMI FL EP052023 2100 UTC FRI AUG 04 2023 AT 2100Z THE CENTER OF HURRICANE DORA WAS LOCATED NEAR LATITUDE 13.8 NORTH...LONGITUDE 128.5 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 95 KTS...110 MPH...175 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 FRI 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 FRI 06Z SAT 18Z SAT 06Z SUN 18Z SUN 18Z MON 18Z TUE PERIODS TO TO TO TO TO TO TO 06Z SAT 18Z SAT 06Z SUN 18Z SUN 18Z MON 18Z TUE 18Z WED FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 15N 130W 34 4 1( 5) X( 5) X( 5) X( 5) X( 5) X( 5) 10N 135W 34 X 1( 1) 2( 3) 1( 4) X( 4) X( 4) X( 4) 15N 135W 34 X 13(13) 19(32) X(32) X(32) X(32) X(32) 15N 135W 50 X 1( 1) 4( 5) X( 5) X( 5) X( 5) X( 5) 15N 135W 64 X X( X) 1( 1) X( 1) X( 1) X( 1) X( 1) 10N 140W 34 X X( X) 3( 3) 4( 7) 2( 9) X( 9) X( 9) 15N 140W 34 X X( X) 6( 6) 33(39) 1(40) X(40) X(40) 15N 140W 50 X X( X) 1( 1) 8( 9) X( 9) X( 9) X( 9) 15N 140W 64 X X( X) X( X) 3( 3) 1( 4) X( 4) X( 4) 10N 145W 34 X X( X) X( X) 1( 1) 12(13) X(13) X(13) 15N 145W 34 X X( X) X( X) 4( 4) 33(37) X(37) X(37) 15N 145W 50 X X( X) X( X) X( X) 9( 9) X( 9) X( 9) 15N 145W 64 X X( X) X( X) X( X) 3( 3) X( 3) X( 3) 10N 150W 34 X X( X) X( X) X( X) 8( 8) 10(18) X(18) 10N 150W 50 X X( X) X( X) X( X) 1( 1) 2( 3) X( 3) 10N 150W 64 X X( X) X( X) X( X) X( X) 1( 1) X( 1) 15N 150W 34 X X( X) X( X) X( X) 19(19) 16(35) X(35) 15N 150W 50 X X( X) X( X) X( X) 3( 3) 7(10) X(10) 15N 150W 64 X X( X) X( X) X( X) 1( 1) 3( 4) X( 4) BUOY 51004 34 X X( X) X( X) X( X) X( X) 4( 4) X( 4) 15N 155W 34 X X( X) X( X) X( X) X( X) 29(29) 1(30) 15N 155W 50 X X( X) X( X) X( X) X( X) 9( 9) 1(10) 15N 155W 64 X X( X) X( X) X( X) X( X) 3( 3) X( 3) 18N 156W 34 X X( X) X( X) X( X) X( X) 2( 2) 1( 3) BUOY 51002 34 X X( X) X( X) X( X) X( X) 3( 3) 3( 6) 10N 160W 34 X X( X) X( X) X( X) X( X) 4( 4) 15(19) 10N 160W 50 X X( X) X( X) X( X) X( X) X( X) 6( 6) 10N 160W 64 X X( X) X( X) X( X) X( X) X( X) 2( 2) 15N 160W 34 X X( X) X( X) X( X) X( X) 6( 6) 28(34) 15N 160W 50 X X( X) X( X) X( X) X( X) X( X) 12(12) 15N 160W 64 X X( X) X( X) X( X) X( X) X( X) 5( 5) 10N 165W 34 X X( X) X( X) X( X) X( X) X( X) 11(11) 10N 165W 50 X X( X) X( X) X( X) X( X) X( X) 3( 3) 15N 165W 34 X X( X) X( X) X( X) X( X) X( X) 27(27) 15N 165W 50 X X( X) X( X) X( X) X( X) X( X) 6( 6) 15N 165W 64 X X( X) X( X) X( X) X( X) X( X) 2( 2) $$ FORECASTER BEVEN

Issued at 2100 UTC FRI AUG 04 2023 000 WTPZ25 KNHC 042034 TCMEP5 HURRICANE DORA FORECAST/ADVISORY NUMBER 17 NWS NATIONAL HURRICANE CENTER MIAMI FL EP052023 2100 UTC FRI AUG 04 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 13.8N 128.5W AT 04/2100Z POSITION ACCURATE WITHIN 15 NM PRESENT MOVEMENT TOWARD THE WEST OR 265 DEGREES AT 16 KT ESTIMATED MINIMUM CENTRAL PRESSURE 964 MB MAX SUSTAINED WINDS 95 KT WITH GUSTS TO 115 KT. 64 KT....... 15NE 10SE 10SW 15NW. 50 KT....... 25NE 15SE 15SW 25NW. 34 KT....... 40NE 40SE 30SW 40NW. 12 FT SEAS..120NE 75SE 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 13.8N 128.5W AT 04/2100Z AT 04/1800Z CENTER WAS LOCATED NEAR 13.8N 127.7W FORECAST VALID 05/0600Z 13.6N 130.8W MAX WIND 90 KT...GUSTS 110 KT. 64 KT... 15NE 10SE 10SW 15NW. 50 KT... 25NE 20SE 15SW 25NW. 34 KT... 40NE 40SE 30SW 40NW. FORECAST VALID 05/1800Z 13.5N 134.0W MAX WIND 85 KT...GUSTS 105 KT. 64 KT... 15NE 10SE 10SW 15NW. 50 KT... 30NE 20SE 20SW 25NW. 34 KT... 50NE 40SE 40SW 50NW. FORECAST VALID 06/0600Z 13.3N 137.5W MAX WIND 85 KT...GUSTS 105 KT. 64 KT... 20NE 10SE 10SW 20NW. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 50NE 40SE 40SW 50NW. FORECAST VALID 06/1800Z 13.1N 141.0W MAX WIND 85 KT...GUSTS 105 KT. 64 KT... 20NE 10SE 10SW 20NW. 50 KT... 30NE 15SE 15SW 30NW. 34 KT... 60NE 40SE 40SW 50NW. FORECAST VALID 07/0600Z 12.9N 144.6W MAX WIND 85 KT...GUSTS 105 KT. 50 KT... 30NE 15SE 15SW 30NW. 34 KT... 60NE 40SE 40SW 60NW. FORECAST VALID 07/1800Z 12.8N 148.4W MAX WIND 85 KT...GUSTS 105 KT. 50 KT... 30NE 15SE 15SW 25NW. 34 KT... 60NE 40SE 30SW 60NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM ON DAY 4 AND 125 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 08/1800Z 12.5N 156.5W MAX WIND 80 KT...GUSTS 100 KT. OUTLOOK VALID 09/1800Z 13.0N 164.0W MAX WIND 75 KT...GUSTS 90 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 13.8N 128.5W NEXT ADVISORY AT 05/0300Z $$ FORECASTER BEVEN

Issued at 1100 AM HST Fri Aug 04 2023 000 WTPZ35 KNHC 042034 TCPEP5 BULLETIN Hurricane Dora Advisory Number 17 NWS National Hurricane Center Miami FL EP052023 1100 AM HST Fri Aug 04 2023 ...DORA WEAKENS SOME MORE AS IT CONTINUES WESTWARD OVER THE OPEN EASTERN PACIFIC... SUMMARY OF 1100 AM HST...2100 UTC...INFORMATION ----------------------------------------------- LOCATION...13.8N 128.5W ABOUT 1370 MI...2205 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA ABOUT 1835 MI...2955 KM E OF SOUTH POINT HAWAII MAXIMUM SUSTAINED WINDS...110 MPH...175 KM/H PRESENT MOVEMENT...W OR 265 DEGREES AT 18 MPH...30 KM/H MINIMUM CENTRAL PRESSURE...964 MB...28.47 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 AM HST (2100 UTC), the center of Hurricane Dora was located near latitude 13.8 North, longitude 128.5 West. Dora is moving toward the west near 18 mph (30 km/h), and this general motion is expected to continue during the next several days. Maximum sustained winds are now near 110 mph (175 km/h) with higher gusts. Some additional weakening is forecast through Saturday, with little change in strength expected on Sunday and Monday. Dora remains a small tropical cyclone. Hurricane-force winds extend outward up to 15 miles (30 km) from the center and tropical-storm-force winds extend outward up to 45 miles (75 km). The estimated minimum central pressure is 964 mb (28.47 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 500 PM HST. $$ Forecaster Beven

...DORA WEAKENS SOME MORE AS IT CONTINUES WESTWARD OVER THE OPEN EASTERN PACIFIC... As of 11:00 AM HST Fri Aug 4 the center of Dora was located near 13.8, -128.5 with movement W at 18 mph. The minimum central pressure was 964 mb with maximum sustained winds of about 110 mph.

MD 1832 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF NORTHERN MISSOURI
Mesoscale Discussion 1832 NWS Storm Prediction Center Norman OK 0304 PM CDT Fri Aug 04 2023 Areas affected...portions of northern Missouri Concerning...Severe potential...Watch possible Valid 042004Z - 042230Z Probability of Watch Issuance...60 percent SUMMARY...The severe threat is gradually increasing across portions of northern MO. Damaging gusts are the main threat though a tornado or two, as well as an instance of large hail, are also possible. Convective trends are being monitored for the need of a WW issuance. DISCUSSION...The remnants of an MCV continue to track eastward along the northeast KS/northwest MO border area, with clearing skies and backed surface winds preceding the MCV. Surface temperatures are rising into the low to mid 80s amid mid to upper 70s F dewpoints, contributing to 1500+ J/kg MLCAPE amid eroding MLCINH. With continued heating and further destabilization, an eventual increase in convective coverage and intensity should take place across northern MO this afternoon. 19Z mesoanalysis/1936Z EAX VAD profile shows elongated low-level hodographs, with the latest mesoanalysis also showing modest 0-3 km CAPE and vertical near-surface vorticity overlapping near the MCV center. As such, storms that manage to organize this afternoon should mature into multicells or perhaps supercells capable of damaging gusts and perhaps a tornado or two, along with an instance of large hail. Given the slower trends in increasing storm coverage and intensity, the timing for the need of a WW issuance remains uncertain. However, a WW issuance may ultimately be needed this afternoon, whenever a appreciable increase in convective trends is noted. ..Squitieri/Goss.. 08/04/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LSX...EAX... LAT...LON 39289513 39909482 40119434 40229340 40129268 39749218 39319226 39029267 38879330 38909394 38959464 39059498 39289513 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Fri Aug 04 2023 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS WITHIN THE NORTHEAST...NORTHERN/CENTRAL MISSOURI...PORTIONS OF THE CENTRAL PLAINS... ...SUMMARY... Scattered severe thunderstorms remain possible across parts of the Northeast, Missouri, and the central into the southern High Plains later today through early tonight. ...20Z Update... Minor changes were made to the wind probabilities within the Mid-South/Southeast to account for observations and stabilization behind ongoing convection. The remainder of the outlook is unchanged. ..Wendt.. 08/04/2023 .PREV DISCUSSION... /ISSUED 1134 AM CDT Fri Aug 04 2023/ ...Synopsis... A broad mid-level trough continues to slowly progress across the Northeast as an upper ridge remains in place across the southern CONUS, with multiple mid-level perturbations cresting the upper ridge over the Central Plains. Though some cloud cover and showers/thunderstorms persist across the Northeast, adequate clearing through the remainder of the morning should efficiently heat the boundary layer beneath cooler mid-level temperatures and stronger flow aloft to promote strong to potentially severe thunderstorms through the afternoon. Meanwhile, residual clouds, showers, and thunderstorms should clear across the MO Valley into the Southeast today, with surface heating contributing to adequate buoyancy to support strong to potentially severe thunderstorms. These storms should initiate with the passage of the aforementioned mid-level impulses cresting the upper ridge. Lastly, upslope low-level flow will support the development of strong to potentially severe thunderstorms across the central into the southern High Plains later this afternoon and evening. ...Northeast... Scattered to potentially widespread thunderstorms are expected to initiate across the Hudson Valley late this morning into early afternoon ahead of a surface lee trough as surface heating continues across the Northeast. 16Z mesoanalysis shows modest (i.e. 6-6.5 C/km) mid-level lapse rates overspreading the Hudson Valley. Nonetheless, -14 to -15 C 500 mb temperatures and 70+ kts of 300 mb flow (in association with an approaching upper-level jet streak) will promote adequate instability (given mid 60s F surface dewpoints) and deep-layer shear to support a severe threat this afternoon. Multicells and transient supercell structures are expected, with large hail and damaging gusts the main concerns. By late afternoon, storms should congeal into one or more clusters. If this occurs, then damaging gusts will become the primary threat. ...MO Valley into the Southeast... Ongoing clouds and precipitation should gradually clear through the afternoon to support increasing buoyancy (perhaps over 3000 J/kg MLCAPE) as 7+ C/km mid-level lapse rates overspreads 70+ F surface dewpoints. The approach of an MCV from the remains of an earlier MCS will support convective initiation later this afternoon around and just east of the KC Metropolitan area. Elongated and curved hodographs (especially in the low-levels) will encourage multicell and supercell structures initially. While damaging gusts are the main threat, locally backed low-level winds ahead of the MCV track may encourage a localized tornado threat for a few hours. However, storms should merge into one or more MCSs later this afternoon, with severe gusts the primary concern. Across the southeast, thunderstorm clusters should develop along the eastern periphery of the upper ridge. Given rich low-level moisture and strong buoyancy (with the 16Z mesoanalysis already showing up to 5000 J/kg SBCAPE in place), water-loaded downdrafts may accompany the stronger storm cores, and at least isolated damaging gusts are possible later this afternoon. ...Central into the Southern High Plains... Upslope flow induced by a surface lee trough, along with diurnal heating, will support the development of at least isolated to potentially scattered thunderstorms late this afternoon, from western SD to the TX Panhandle. A plume of 7-8 C/km mid-level lapse rates will advect over the central High Plains in tandem with the ejection of a subtle 700 mb impulse. 2000+ J/kg MLCAPE and an increase in deep-layer shear will result, with modestly lengthening hodographs (and 40 kts of effective bulk shear) expected. Multicells and supercells are expected to be the initial storm modes, with both severe hail wind the primary threats. By evening though, weak low-level shear should encourage outflow and subsequent cold pool mergers, with severe gusts then becoming the dominant severe threat. A few outflow-dominant thunderstorms may also develop along the surface trough across portions of the southern High Plains by afternoon peak heating. These storms will develop atop a dry, mixed boundary layer, with a couple of severe gusts possible. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Fri Aug 04 2023 Valid 051200Z - 061200Z No changes are needed to the Day 2 Fire Weather Outlook. See previous discussion below. ..Thornton.. 08/04/2023 .PREV DISCUSSION... /ISSUED 0206 AM CDT Fri Aug 04 2023/ ...Synopsis... Elevated fire weather concerns will continue for Saturday across the southern Plains and parts of the Southwest/Four Corners. Isolated dry thunderstorms are also expected across parts of the Pacific Northwest and into the northern Great Basin. ...Southern High Plains... Medium-range guidance shows good agreement in the gradual ejection of the northern Rockies upper low into the Plains through the day Saturday. Lee troughing, coupled with thermally-driven pressure falls, should yield a modest surface low over the western OK/northwest TX where temperatures are expected to climb into the 100-105 F range. Ensemble guidance suggests the probability of sustained 15+ mph winds is generally low across central TX where fuels are currently most critical. A stronger pressure gradient near the surface low may support 15 mph winds (and hence the greatest fire weather concern) across northwest TX/southwest OK during peak heating. However, this region may also see afternoon thunderstorms per latest forecast soundings and ensemble QPF probabilities, which casts uncertainty into the duration and coverage of the fire weather threat. While elevated concerns appear most likely at this time, the potential for critical conditions will be monitored considering the critical nature of the fuels. ...Arizona into New Mexico... The aforementioned surface low over the Panhandles region will also augment westerly flow across northern AZ into northern NM. Sustained winds near 15-20 mph coupled with 15-20% RH appear likely based on both deterministic solutions and ensemble probabilities. While elevated conditions appear most probable, drier/windier solutions hint at the potential for critical conditions. Scattered pockets of wetting rain over the past 7 days complicate fuel status to some degree, but at least low-end fire weather concerns appear likely. ...Dry Thunderstorms... A slow-moving upper trough is expected to linger over the Pacific Northwest through the day Saturday. An influx of mid-level Pacific moisture and lift associated with this feature will result in another day of isolated to scattered thunderstorms. Forecast soundings continue to show PWAT values near 0.6 to 0.75 inches with deep, well-mixed boundary layers conducive for a mix of wet and dry thunderstorms from northwest NV into OR and adjacent areas of northern CA. Dry thunderstorms are also possible across parts of eastern UT and western CO, but recent rainfall appears to have mitigated fuel status based on recent fuel guidance. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0584 Status Updates
040- STATUS REPORT ON WW 584 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 E DUJ TO 35 NNW IPT TO 30 NNE BGM TO 40 NNE UCA TO 25 ENE MSS. ..LYONS..08/04/23 ATTN...WFO...BOX...ALY...GYX...PHI...BGM...BUF...BTV...OKX... CTP... STATUS REPORT FOR WS 584 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS CTC003-005-042040- CT . CONNECTICUT COUNTIES INCLUDED ARE HARTFORD LITCHFIELD MEC031-042040- ME . MAINE COUNTIES INCLUDED ARE YORK MAC003-009-011-013-015-017-025-027-042040- MA . MASSACHUSETTS COUNTIES INCLUDED ARE BERKSHIRE ESSEX FRANKLIN HAMPDEN HAMPSHIRE MIDDLESEX Read more

WW 584 SEVERE TSTM CT MA ME NH NJ NY PA VT CW 041605Z - 050000Z
0- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 584 NWS Storm Prediction Center Norman OK 1205 PM EDT Fri Aug 4 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northwestern Connecticut Much of Massachusetts Far southern Maine Central and southern New Hampshire Northwestern New Jersey Central and eastern New York Parts of central and eastern Pennsylvania Central and southern Vermont Coastal Waters * Effective this Friday afternoon and evening from 1205 PM until 800 PM EDT. * Primary threats include... Scattered damaging wind gusts to 65 mph possible Scattered large hail events to 1.5 inches in diameter possible SUMMARY...Thunderstorms are forecast to continue to develop across portions of Pennsylvania and New York and into New England early this afternoon, intensifying and evolving into clusters/bands of storms with time. Large hail up to golf ball size, and wind gusts locally exceeding 60 MPH are expected with the strongest storms. The severe thunderstorm watch area is approximately along and 110 statute miles east and west of a line from 25 miles north northwest of Lebanon NH to 35 miles southeast of State College PA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). 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 55 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 27030. ...Goss Read more

WW 584 SEVERE TSTM CT MA ME NH NJ NY PA VT CW 041605Z - 050000Z
0- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 584 NWS Storm Prediction Center Norman OK 1205 PM EDT Fri Aug 4 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northwestern Connecticut Much of Massachusetts Far southern Maine Central and southern New Hampshire Northwestern New Jersey Central and eastern New York Parts of central and eastern Pennsylvania Central and southern Vermont Coastal Waters * Effective this Friday afternoon and evening from 1205 PM until 800 PM EDT. * Primary threats include... Scattered damaging wind gusts to 65 mph possible Scattered large hail events to 1.5 inches in diameter possible SUMMARY...Thunderstorms are forecast to continue to develop across portions of Pennsylvania and New York and into New England early this afternoon, intensifying and evolving into clusters/bands of storms with time. Large hail up to golf ball size, and wind gusts locally exceeding 60 MPH are expected with the strongest storms. The severe thunderstorm watch area is approximately along and 110 statute miles east and west of a line from 25 miles north northwest of Lebanon NH to 35 miles southeast of State College PA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). 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 55 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 27030. ...Goss Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Fri Aug 04 2023 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF THE CENTRAL PLAINS INTO THE MISSOURI VALLEY... ...SUMMARY... Severe thunderstorms are expected across portions of the central Plains to the Lower Missouri/Middle Mississippi Valley vicinity on Saturday. Damaging gusts (some 75+ mph) and large hail (some 2+ inches) will be the primary severe weather hazards. ...Synopsis... A closed upper low currently within the northern Plains is expected to become more of an open wave and move southward/southeastward on Saturday. Mid/upper-level winds will increase through the period within the central High Plains eastward into the Missouri Valley as a result. Farther east, an MCV is forecast to track into the mid-Mississippi/lower Ohio Valley vicinity. At the surface, a remnant stationary boundary, perhaps reinforced by warm-advection precipitation, will remain from Missouri into the southern Plains. To the north, a surface low will deepen in South Dakota and eventually move into the Midwest along with its parent shortwave trough. This will act to push a cold front into the central Plains by Sunday morning. A secondary surface low is also forecast to develop in the southern High Plains. ...Central High Plains into Kansas... Upslope flow into the terrain is expected to be maintained ahead of the cold front which should approach by late afternoon. Upper 50s F to low 60s F dewpoints should be sufficient for a cluster or two of storms to develop within the terrain and spread eastward into eastern Colorado and western Kansas. There continues to be some uncertainty as to potential convection within southern Kansas into northern Oklahoma overnight Friday into Saturday morning. Weak warm advection is still predicted by most guidance even into the afternoon. What impact this activity will have on the forecast does remain unclear. Even so, moderate to strong buoyancy is expected within eastern Colorado and south of areas impacted by early precipitation. Winds at mid/upper levels will be increasing into early evening. Hodographs will consequently become more favorable for supercells and large/very-large hail. It is not clear how quickly upscale growth will occur, but an increase in 850 mb flow from the south across West Texas will likely promote increasing storm coverage during the evening. Strong/severe wind gusts will also be possible with supercells, including gusts in excess of 75 mph. The spatial extent of significant gust potential will be conditional on degree and timing of upscale growth. Damaging wind potential will persist into the evening in some fashion across Kansas into perhaps western Missouri. ...Mid-Missouri Valley... Near the surface low, storm development appears likely from southeast South Dakota into eastern Nebraska. Shear will decrease with northern extent, as will buoyancy, with the mid-level jet being generally near the Nebraska/Kansas border. However, some supercell structures appear possible that will be capable of large hail and damaging winds. A narrow corridor of backed surface winds near the low could support a risk for a tornado as well, but hodographs at mid/upper-levels do not appear favorable for sustained/strong mesocyclones. ...Lower Ohio Valley Vicinity... An MCV now in the Mid-Missouri Valley region is expected to progress into Illinois by early Saturday morning. Cloud cover and precipitation with this feature will mean some uncertainty in the magnitude and location of severe risk during the afternoon. The degree of surface heating will be the key and not all models suggest it will occur. However, there appears to be a conditionally favorable environment for marginal supercell structures capable of isolated damaging winds and a brief tornado or two. ..Wendt.. 08/04/2023 Read more

000
ABPZ20 KNHC 041727
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Fri Aug 4 2023

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

Active Systems:
The National Hurricane Center is issuing advisories on Hurricane
Dora, located over a thousand miles west-southwest of the southern
tip of the Baja California Peninsula.

Off the coast of Southwestern Mexico:
Showers and thunderstorms associated with a broad area of low
pressure located about 250 miles south-southeast of Manzanillo,
Mexico, have become better organized over the past several hours.
Environmental conditions appear conducive for further development
and a tropical depression is likely to form during the next day or
so as it moves west-northwestward or northwestward, parallel to but
not far offshore of the southwestern coast of Mexico. Interests
along the southwestern coast of Mexico and the southern portion of
the Baja California peninsula should monitor the progress of this
system during the next few days.
* Formation chance through 48 hours...high...80 percent.
* Formation chance through 7 days...high...90 percent.

$$
Forecaster Beven

000
ABNT20 KNHC 041710
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Fri Aug 4 2023

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

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

$$
Forecaster Roberts

Much of Northwest Montana will be under Stage 2 fire restrictions starting on Saturday, Aug. 5. The affected federal, state and private jurisdictions in stage 2 restrictions were Flathead National Forest, including Hungry Horse, Glacier View; Swan Lake, Spotted Bear and Tally Ranger Districts to include the Great Bear Wilderness, Mission Mountain Wilderness, and the Flathead National Forest portion of the Bob Marshall Wilderness; Kootenai National Forest, including Rexford, Fortine, Three Rivers, Libby and Cabinet Ranger Districts; Glacier National Park; US Fish & Wildlife Service; Montana Department of Natural Resources and Conservation, including Kalispell, Libby, Stillwater, Swan and Plains Units; Montana Fish, Wildlife, and Parks, Region 1 within Flathead County, Lake County, Lincoln County, Sanders County; Flathead County – Stage 2 fire restrictions; Lake County – Stage 2 fire restrictions; Lincoln County – Stage 2 fire restrictions; Sanders County– Stage 2 fire restrictions; Green Diamond was not allowing campfires on their lands; Flathead Ridge Ranch prohibited campfires on their lands; Southern Pine Plantation of Montana was not allowing campfires; Stimson Private Timber Company was not allowing campfires on their lands; and Stoltze Timber Company was not allowing campfires on their lands. On Aug. 7, Stoltze will close their land to public access of any kind. KPAX (Missoula, Mont.), Aug 3, 2023