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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1233 PM CDT Wed Aug 02 2023 Valid 031200Z - 041200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR FAR NORTHEAST COLORADO...FAR SOUTHWEST NEBRASKA...AND NORTHWEST KANSAS... ...SUMMARY... Scattered severe thunderstorms are possible over the central High Plains beginning Thursday afternoon and continuing through late Thursday evening. Severe gusts in the 60-80 mph range are the primary hazard. ...Synopsis... The mean upper flow regime on Thursday will be characterized by a ridge oriented over the Great Plains and a trough centered over the lower Great Lakes/Northeast. A convectively-aided mid-level shortwave trough is forecast to move from the OH/MS River confluence into GA through the late evening. Another convectively-aided disturbance is forecast to move from eastern UT/southwest WY east into the north-central High Plains. Embedded within the larger-scale southeast Canada mid-level trough, an impulse is forecast to move southeast through its base during the period. These three features will focus strong to severe thunderstorm potential on Thursday/Thursday night. ...Central High Plains vicinity... Mid/upper westerly flow around 30-40 kt is forecast as the mid-level perturbation ejects eastward through the afternoon/evening. East/southeasterly low-level flow will maintain 60s F surface dewpoints across the region, supporting a corridor of 1500-3000 J/kg MLCAPE. Effective-shear magnitudes around 35-45 kt will support organized cells capable of large hail initially and an increasing risk for severe gusts with time. Steep 700-500 mb lapse rates will overspread the Enhanced Risk categorical area over eastern CO/western KS as 0-2 km lapse rates become adequately steep by the 22-00z timeframe. Models are is relatively good agreement in showing an organized thunderstorm cluster developing over eastern CO and becoming more expansive as it encounters increasingly rich moisture and larger CAPE. The latest CAM guidance shows a focused corridor where severe gusts are most probable and a risk for significant gusts (exceeding 75 mph) may be realized during the MCS's mature phase during the evening centered over northwest KS. This activity will continue east into central KS with a gradually reducing wind hazard into the late night. ...TN Valley vicinity... There is high confidence for a corridor of showers/thunderstorms to be ongoing Thursday morning over the lower OH Valley into TN. On the southern and western periphery of cloud debris/convective outflow, differential heating will favor additional storm development during the day across the TN Valley with more isolated storm coverage along the trailing baroclinic zone perhaps extending into the Ozarks. Appreciably strong northwesterly mid/upper flow will aid in storm organization once robust storms develop. It seems probable at least some linear configuration will evolve with the diurnal storm activity centered over northern AL. Strong heating amidst a moist/mixed boundary layer will lend potential for damaging gusts with this threat peaking during the mid-late afternoon. If uncertainty regarding mesoscale details is reduced in terms of placement of the most intense storms, additional refinement of severe probabilities may become necessary. ...Great Lakes/Northeast vicinity... Model guidance doesn't show much change to the previously issued forecast in showing a shortwave impulse embedded in the larger-scale eastern trough moving across the Great Lakes much of the period. A belt of 30-40 kt midlevel flow will overlap a seasonally moist boundary layer ahead of a south/southeast-advancing cold front. MLCAPE generally less than 1500 J/kg is forecast amid modest midlevel lapse rates. Low-level flow will be fairly light, but speed shear will support effective-shear magnitudes around 25-35 kt. Forecast soundings show elongated/straight hodographs, and marginally severe hail will be possible with stronger updrafts. Strong heating will result in steep low-level lapse rates, and strong outflow winds also will be possible. ..Smith.. 08/02/2023 Read more

There were more reports of illness and death in cows and small ruminants that may have ingested perilla mint during drought, according to University of Missouri Extension specialists. Perilla mint, a toxic summer annual, is also known as rattlesnake weed, purple mint and beefsteak plant. Three Rivers Publishing, Inc. (Cuba, Mo.), Aug 2, 2023

Thrips, tiny insects with fringed wings that thrive amid drought, consumed the first third of the strawberry crop in Iowa City in the east central part of the state. Wildlife has had less natural food available to them in the wild and have taken to searching for food and water on farms, gardens and urban areas. The Gazette (Cedar Rapids, Iowa), July 31, 2023

You-pick farms across Iowa have seen decreased yields, smaller produce and fewer customers. In Nevada in central Iowa, only about half of the strawberry crops at a berry farm survived the past two years of drought. The farmer irrigates, but could not keep up with water demand. The Iowa Department of Natural Resources restricted his well water usage from 20 acres a day to 1 acre a day. The Gazette (Cedar Rapids, Iowa), July 31, 2023

A blueberry grower in Brighton did not have enough well water to irrigate her berries this summer after heat and drought during the 2022 summer caused water production to falter. The farmer had to cancel a day of picking appointments because there were not enough ripe berries. The Gazette (Cedar Rapids, Iowa), July 31, 2023

Heat, dry weather and increased water use in Emporia have contributed to the uptick in water main breaks. KVOE (Emporia, Kan.), Aug 1, 2023

The Brazos River Authority and the Bell County Water Control & Improvement District No. 1 on Aug. 1, 2023, issued a Stage 2 Drought Warning for all communities that draw water from Lake Belton. Water customers in Killeen, Harker Heights, Belton, Copperas Cove, and others were asked to curb water use by 10%. Most Bell County towns have been conserving water since August 2022. Lake Belton was just over 578 feet, which was more than 15 feet below full pool level. KWKT FOX 44 News (Waco, Texas), Aug 1, 2023

No Mesoscale Discussions are in effect as of Tue Aug 1 22:16:06 UTC 2023.

WW 0578 Status Updates
STATUS REPORT ON WW 578 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..LYONS..08/01/23 ATTN...WFO...FGF...GGW...BIS... STATUS REPORT FOR WS 578 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC005-027-029-051-087-089-107-111-113-119-125-167-012240- MN . MINNESOTA COUNTIES INCLUDED ARE BECKER CLAY CLEARWATER GRANT MAHNOMEN MARSHALL NORMAN OTTER TAIL PENNINGTON POLK RED LAKE WILKIN MTC021-083-085-109-012240- MT . MONTANA COUNTIES INCLUDED ARE DAWSON RICHLAND ROOSEVELT WIBAUX NDC001-003-007-011-015-017-021-025-027-029-031-033-035-037-039- 041-043-045-047-051-053-055-057-059-061-063-065-073-077-081-083- 085-087-089-091-093-097-103-105-012240- ND . NORTH DAKOTA COUNTIES INCLUDED ARE Read more

WW 578 SEVERE TSTM MN MT ND 012050Z - 020500Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 578 NWS Storm Prediction Center Norman OK 350 PM CDT Tue Aug 1 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northwest Minnesota Extreme northeast Montana North Dakota * Effective this Tuesday afternoon from 350 PM until Midnight CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2 inches in diameter possible Scattered damaging wind gusts to 70 mph possible SUMMARY...Widely scattered thunderstorm development is expected this afternoon from northwest Minnesota westward across North Dakota, where the environment will favor splitting supercells capable of producing large hail and damaging winds. Additional storm development is expected near the Montana/North Dakota border, with the potential for these storms to grow into a cluster with damaging winds while moving east-southeastward through early tonight. The severe thunderstorm watch area is approximately along and 65 statute miles north and south of a line from 65 miles south southwest of Williston ND to 25 miles northeast of Detroit Lakes MN. 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. && AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 30020. ...Thompson Read more

Issued at 2100 UTC TUE AUG 01 2023 000 WTPZ25 KNHC 012100 TCMEP5 TROPICAL STORM DORA FORECAST/ADVISORY NUMBER 5 NWS NATIONAL HURRICANE CENTER MIAMI FL EP052023 2100 UTC TUE AUG 01 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). TROPICAL STORM CENTER LOCATED NEAR 16.1N 110.1W AT 01/2100Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST OR 270 DEGREES AT 14 KT ESTIMATED MINIMUM CENTRAL PRESSURE 998 MB MAX SUSTAINED WINDS 55 KT WITH GUSTS TO 65 KT. 50 KT....... 10NE 0SE 0SW 10NW. 34 KT....... 30NE 20SE 20SW 30NW. 12 FT SEAS.. 60NE 0SE 0SW 0NW. 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 16.1N 110.1W AT 01/2100Z AT 01/1800Z CENTER WAS LOCATED NEAR 16.1N 109.4W FORECAST VALID 02/0600Z 16.1N 112.3W MAX WIND 70 KT...GUSTS 85 KT. 64 KT... 10NE 0SE 0SW 10NW. 50 KT... 20NE 10SE 10SW 20NW. 34 KT... 40NE 20SE 20SW 40NW. FORECAST VALID 02/1800Z 15.9N 115.1W MAX WIND 90 KT...GUSTS 110 KT. 64 KT... 10NE 10SE 5SW 10NW. 50 KT... 20NE 20SE 10SW 20NW. 34 KT... 40NE 30SE 30SW 40NW. FORECAST VALID 03/0600Z 15.4N 117.9W MAX WIND 105 KT...GUSTS 130 KT. 64 KT... 15NE 10SE 10SW 15NW. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 50NE 30SE 30SW 50NW. FORECAST VALID 03/1800Z 15.0N 121.0W MAX WIND 110 KT...GUSTS 135 KT. 64 KT... 15NE 10SE 15SW 15NW. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 50NE 40SE 40SW 60NW. FORECAST VALID 04/0600Z 14.5N 124.1W MAX WIND 105 KT...GUSTS 130 KT. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 50NE 40SE 40SW 60NW. FORECAST VALID 04/1800Z 13.9N 127.1W MAX WIND 100 KT...GUSTS 120 KT. 50 KT... 30NE 20SE 20SW 30NW. 34 KT... 50NE 40SE 40SW 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 05/1800Z 13.2N 133.5W MAX WIND 95 KT...GUSTS 115 KT. OUTLOOK VALID 06/1800Z 12.5N 139.5W MAX WIND 90 KT...GUSTS 110 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 16.1N 110.1W NEXT ADVISORY AT 02/0300Z $$ FORECASTER PAPIN

Issued at 300 PM MDT Tue Aug 01 2023 920 WTPZ45 KNHC 012048 TCDEP5 Tropical Storm Dora Discussion Number 5 NWS National Hurricane Center Miami FL EP052023 300 PM MDT Tue Aug 01 2023 Dora continues to become better organized this afternoon. The storm has maintained a well-defined curved band in its eastern semicircle as a cold central dense overcast has persisted near the center. Subjective intensity estimates from TAFB and SAB remained unchanged this afternoon, but we also received an ASCAT-B pass at 1728 UTC which showed a peak-wind retrieval of 51 kt. Due to the very small size of the wind field seen from this scatterometer pass, it is quite possible this value may be undersampling the storm's maximum sustained winds. Therefore, the intensity was nudged upward to 55 kt for this advisory. Dora might be starting to make a gradual leftward turn, with the most recent estimated motion due west at 270/14 kt. There is not a ton new to report for the track forecast this afternoon, with a large mid-level ridge expected to build northwestward relative to Dora. This evolution should result in Dora turning west-southwestward beginning tomorrow and continuing through the end of the forecast period. The track guidance remains in fairly good agreement, and the latest NHC track forecast is very similar to the previous one, in best agreement with the HFIP corrected consensus approach (HCCA). So far, Dora shows little signs of pausing its intensification rate this afternoon. Vertical wind shear remains very low (at or under 5 kt) and sea-surface temperatures (SSTs) remain very warm (29 C or warmer). Assuming dry air does not disrupt the small inner core that has formed today, rapid intensification (RI) appears likely for the next day or so. This expectation is supported by SHIPS-RII guidance from both the ECMWF and GFS, which show a 74 percent chance of a 35 kt increase in intensity over the next 24 hours. These values are 12-13 times above its climatological mean. Therefore, the latest NHC intensity forecast shows this rate of intensification over the next day, ultimately peaking Dora as a 110-kt category 3 hurricane in 48 hours. This intensity forecast is not that far off the most recent HCCA intensity aid but is still a bit lower than the latest HAFS-A/B guidance. Thereafter, SSTs begin to drop down to 27 C and a modest increase in easterly shear may lead to some gradual weakening. Hard-to-predict inner core changes during this period may also result in some intensity fluctuations, possibly larger than shown here given how small Dora is forecast to remain. FORECAST POSITIONS AND MAX WINDS INIT 01/2100Z 16.1N 110.1W 55 KT 65 MPH 12H 02/0600Z 16.1N 112.3W 70 KT 80 MPH 24H 02/1800Z 15.9N 115.1W 90 KT 105 MPH 36H 03/0600Z 15.4N 117.9W 105 KT 120 MPH 48H 03/1800Z 15.0N 121.0W 110 KT 125 MPH 60H 04/0600Z 14.5N 124.1W 105 KT 120 MPH 72H 04/1800Z 13.9N 127.1W 100 KT 115 MPH 96H 05/1800Z 13.2N 133.5W 95 KT 110 MPH 120H 06/1800Z 12.5N 139.5W 90 KT 105 MPH $$ Forecaster Papin

5-Day Uncertainty Track last updated Tue, 01 Aug 2023 20:43:59 GMT


Wind Speed Probabilities last updated Tue, 01 Aug 2023 21:22:53 GMT

Issued at 2100 UTC TUE AUG 01 2023 000 FOPZ15 KNHC 012041 PWSEP5 TROPICAL STORM DORA WIND SPEED PROBABILITIES NUMBER 5 NWS NATIONAL HURRICANE CENTER MIAMI FL EP052023 2100 UTC TUE AUG 01 2023 AT 2100Z THE CENTER OF TROPICAL STORM DORA WAS LOCATED NEAR LATITUDE 16.1 NORTH...LONGITUDE 110.1 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 55 KTS...65 MPH...100 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 TUE 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 TUE 06Z WED 18Z WED 06Z THU 18Z THU 18Z FRI 18Z SAT PERIODS TO TO TO TO TO TO TO 06Z WED 18Z WED 06Z THU 18Z THU 18Z FRI 18Z SAT 18Z SUN FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT ISLA CLARION 34 X 3( 3) 1( 4) X( 4) X( 4) X( 4) X( 4) 15N 115W 34 X 55(55) 7(62) 1(63) X(63) X(63) X(63) 15N 115W 50 X 13(13) 5(18) X(18) X(18) X(18) X(18) 15N 115W 64 X 4( 4) 4( 8) X( 8) X( 8) X( 8) X( 8) 15N 120W 34 X 1( 1) 20(21) 73(94) X(94) X(94) X(94) 15N 120W 50 X X( X) 3( 3) 65(68) 2(70) X(70) X(70) 15N 120W 64 X X( X) 1( 1) 47(48) 3(51) X(51) X(51) 10N 125W 34 X X( X) X( X) X( X) 5( 5) 1( 6) X( 6) 15N 125W 34 X X( X) X( X) 4( 4) 82(86) 1(87) X(87) 15N 125W 50 X X( X) X( X) X( X) 59(59) 1(60) X(60) 15N 125W 64 X X( X) X( X) X( X) 39(39) 1(40) X(40) 10N 130W 34 X X( X) X( X) X( X) 1( 1) 11(12) X(12) 10N 130W 50 X X( X) X( X) X( X) X( X) 2( 2) X( 2) 10N 130W 64 X X( X) X( X) X( X) X( X) 1( 1) X( 1) 15N 130W 34 X X( X) X( X) X( X) 14(14) 50(64) 1(65) 15N 130W 50 X X( X) X( X) X( X) 2( 2) 29(31) X(31) 15N 130W 64 X X( X) X( X) X( X) X( X) 18(18) X(18) 10N 135W 34 X X( X) X( X) X( X) X( X) 8( 8) 10(18) 10N 135W 50 X X( X) X( X) X( X) X( X) 1( 1) 4( 5) 10N 135W 64 X X( X) X( X) X( X) X( X) X( X) 3( 3) 15N 135W 34 X X( X) X( X) X( X) X( X) 31(31) 18(49) 15N 135W 50 X X( X) X( X) X( X) X( X) 11(11) 13(24) 15N 135W 64 X X( X) X( X) X( X) X( X) 4( 4) 9(13) 10N 140W 34 X X( X) X( X) X( X) X( X) X( X) 20(20) 10N 140W 50 X X( X) X( X) X( X) X( X) X( X) 5( 5) 10N 140W 64 X X( X) X( X) X( X) X( X) X( X) 3( 3) 15N 140W 34 X X( X) X( X) X( X) X( X) X( X) 32(32) 15N 140W 50 X X( X) X( X) X( X) X( X) X( X) 11(11) 15N 140W 64 X X( X) X( X) X( X) X( X) X( X) 6( 6) $$ FORECASTER PAPIN

Issued at 300 PM MDT Tue Aug 01 2023 000 WTPZ35 KNHC 012041 TCPEP5 BULLETIN Tropical Storm Dora Advisory Number 5 NWS National Hurricane Center Miami FL EP052023 300 PM MDT Tue Aug 01 2023 ...DORA CONTINUES TO INTENSIFY... SUMMARY OF 300 PM MDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...16.1N 110.1W ABOUT 430 MI...695 KM WSW OF MANZANILLO MEXICO MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H PRESENT MOVEMENT...W OR 270 DEGREES AT 16 MPH...26 KM/H MINIMUM CENTRAL PRESSURE...998 MB...29.47 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 Storm Dora was located near latitude 16.1 North, longitude 110.1 West. Dora is moving toward the west near 16 mph (26 km/h) and this motion is expected to continue with a gradual turn towards the west-southwest over the next few days. Maximum sustained winds have increased to near 65 mph (100 km/h) with higher gusts. Rapid intensification is forecast during the next 24-36 hours and Dora could become a major hurricane on Thursday. Dora is a small tropical cyclone with tropical-storm-force winds extending outward only up to 35 miles (55 km) from the center. The estimated minimum central pressure is 998 mb (29.47 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 900 PM MDT. $$ Forecaster Papin

...DORA CONTINUES TO INTENSIFY... As of 3:00 PM MDT Tue Aug 1 the center of Dora was located near 16.1, -110.1 with movement W at 16 mph. The minimum central pressure was 998 mb with maximum sustained winds of about 65 mph.

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Tue Aug 01 2023 Valid 021200Z - 031200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL TEXAS INTO SOUTHWEST OKLAHOMA... The Critical area was expanded slightly based on the latest high-resolution guidance. Farther west, locally elevated fire-weather conditions are possible in the Cascade gaps, though these conditions appear too localized for highlights. For additional details, see the previous discussion below. ..Weinman.. 08/01/2023 .PREV DISCUSSION... /ISSUED 1225 AM CDT Tue Aug 01 2023/ ...Synopsis... A surface cyclone will continue to slowly deepen across the central Plains on Wednesday as the upper-level ridge continues to deamplify. This will maintain a pressure gradient across the southern Plains, with a strengthening low-level jet late Wednesday afternoon and Wednesday evening. As a result, 15 to 20 mph winds are expected from central Texas into northern Oklahoma with relative humidity of 20 to 30 percent. While these conditions are well within the range of Elevated fire-weather criteria, they are borderline for a Critical area. However, fuels are very dry in the region and with temperatures over 100F, are expected to continue to dry further. Therefore, sustained Elevated conditions may be more capable of large-fire potential than typical Critical fire-weather conditions due to the fuel status. This warrants a Critical delineation for areas along and west of I-35 in central and northern Texas and into far southwest Oklahoma. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0249 PM CDT Tue Aug 01 2023 Valid 012000Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON THROUGH EARLY TONIGHT FOR PARTS OF THE NORTHERN PLAINS AND CENTRAL HIGH PLAINS... ...SUMMARY... Severe-thunderstorm gusts are most probable over parts of the central High Plains and much of North Dakota to northwestern Minnesota, along with at least isolated large hail. ...20Z Update... Overall forecast remains on track with no changes needed to the existing outlook. Late afternoon thunderstorm development is still anticipated over ND, both along the front in north-central ND and in the MT/ND border vicinity. The environmental conditions still support supercells capable of large hail and damaging gusts. Additionally, ongoing thunderstorms across central CO as are still expected to grow upscale later this evening, with an attendant threat for severe outflow gusts and isolated large hail. ..Mosier.. 08/01/2023 .PREV DISCUSSION... /ISSUED 1119 AM CDT Tue Aug 01 2023/ ...Northern Plains through tonight... A midlevel shortwave trough is cresting the midlevel ridge and will continue east-southeastward over southern SK/AB toward ON, as an associated weak cold front moves southeastward into ND. Convection is ongoing in a few clusters near the ND/MT/SK border and northwest MN along the north edge of the unstable warm sector. Some form of these storms could persist through the afternoon, though the main severe threat is expected to be additional development along the front and/or outflow boundaries by mid-late afternoon. Steep midlevel lapse rates, boundary-layer dewpoints in the 65-70 F range and daytime heating will boost MLCAPE to 2000 J/kg or greater as convective inhibition weakens. Low-level flow will be weak beneath moderately strong mid-upper westerly flow, resulting in small low-level hodographs and longer hodographs above about 4 km AGL. This environment will support a mix of multicell clusters and some supercells capable of producing large hail and damaging winds as convection spreads southeastward late this afternoon into early tonight. ...Central High Plains this evening... Within the monsoonal moisture plume, convectively-enhanced waves will move slowly eastward from UT/WY/CO toward NE. Thunderstorms are expected to form later this afternoon near and just east of the Front Range in a weak upslope flow regime in CO, and convection will subsequently grow upscale into a cluster or two across northeast CO and vicinity this evening. Moderate buoyancy and relatively weak vertical shear will mainly favor multicell clusters capable of producing occasional severe outflow gusts and isolated large hail. ...MO area through tonight... Elevated convection persists late this morning over central MO in a low-level warm advection regime, though this convection is expected to diminish as warm advection weakens this afternoon. There will be a low chance for afternoon storm development on the west edge of the cloud debris and northeast edge of the hot surface temperatures/deeper mixing near the KS/MO border, with a conditional wind/hail threat. The more probable scenario will be for renewed thunderstorm development tonight as warm advection increases again on the nose of a southwesterly low-level jet. The overnight storms will be capable of producing isolated large hail and possibly a few strong outflow gusts. ...Carolinas to FL this afternoon... Surface heating with lingering low-level moisture, beneath midlevel drying, will result in moderate destabilization across the eastern Carolinas, where isolated thunderstorms are expected this afternoon along the sea breeze and subtle terrain influences inland. Buoyancy will be larger to the south (>2500 J/kg MLCAPE from southeast GA southward) where widely scattered afternoon thunderstorms are expected mainly inland from the west coast sea breeze. The moderate buoyancy, DCAPE near 1000 J/kg, and some modest enhancement to vertical shear from north FL northward will support a low-end threat for strong/damaging downburst winds. Read more

000
ABPZ20 KNHC 011733
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Tue Aug 1 2023

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

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Dora, located several hundred miles off the southwestern coast
of Mexico.

Off the coast of Southwestern Mexico:
An area of low pressure is forecast to form towards the latter part
of this week a few hundred miles south of the coast of southwestern
Mexico. Thereafter, some gradual development of this system is
possible, and a tropical depression could form by early next week
while it moves west-northwestward or northwestward, roughly parallel
to the southwestern coast of Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...50 percent.

&&
Public Advisories on Tropical Storm Dora are issued under WMO
header WTPZ35 KNHC and under AWIPS header MIATCPEP5.
Forecast/Advisories on Tropical Storm Dora are issued under
WMO header WTPZ25 KNHC and under AWIPS header MIATCMEP5.

$$
Forecaster Papin

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Tue Aug 01 2023 Valid 021200Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL MISSOURI INTO SOUTHERN ILLINOIS... ...SUMMARY... Thunderstorms capable of damaging gusts are possible from central Missouri into southern Illinois Wednesday afternoon through evening. Isolated strong to severe thunderstorms capable of producing damaging gusts and hail are also possible across the Upper Great Lakes region and central High Plains. ...Synopsis... Upper ridging is forecast to remain in place over the southern Plains and Lower MS Valley, keeping that region hot and dry. Some modestly enhanced mid-level flow will exist from the northern Plains/Upper Midwest through the Mid-Atlantic, between the southern Plains ridge and an upper low over the Hudson Bay. A shortwave trough and associated surface low will likely move through this enhanced flow across Ontario. An attendant cold front is expected to move into the northern Plains, Upper Midwest, and Upper Great Lakes, with some thunderstorms possible along the front during afternoon and evening. Additionally, a convectively induced vorticity maximum will likely track eastward over the central Plains and into the Mid/Lower MO Valley. Some thunderstorms are possible from the Mid MO Valley into the Mid MS Valley as this vorticity maximum interacts with the moist and buoyant air mass over the region. ...Mid MO Valley into the Mid MS Valley... Numerous showers and thunderstorms will likely be ongoing Wednesday morning in an arc from far eastern NE to southeast MO/southern IL/far western KY, remnant from overnight storms from the Mid MO Valley into the Mid MS Valley. These storms will likely dissipate by late morning/early afternoon, but residual cloud cover and resulting differential heating will help induce a warm-front-like boundary across MO. Dewpoints are expected to be in the mid 70s in the vicinity of this boundary Wednesday afternoon, contributing to moderate/strong buoyancy. Even with strong daytime heating south/west of the boundary, some convective inhibition will likely persist, particularly with southwestward extent, where mixing will be greatest. However, convergence along this differential heating zone, combined with slightly higher dewpoints and less overall mixing, as well as ascent from the approaching vorticity maximum, is expected to result in convective initiation. Strong buoyancy will support a risk for hail within the first hour or so of development, before cell interactions and outflow-dominant structures influence a more linear storm mode. Additionally, given the presence of a surface boundary and some more southeasterly surface winds, a tornado or two cannot be entirely ruled out. However, a somewhat quick transition to a predominantly linear mode is anticipated, with at least some chance for cold pool organization into a coherent linear convective system. This system should then track southeastward along the buoyancy gradient into southeast MO, southern IL, and potentially even far western KY. ...Upper Midwest into the Upper Great Lakes... Moderate buoyancy is anticipated ahead of the approaching cold front mentioned in the synopsis. Convergence along the boundary will be modest, with higher storm coverage expected across Upper MI versus farther west across northern WI and northeast MN. Even so, expected moderate buoyancy will combine with 30-40 kt of effective bulk shear to support organized thunderstorms. Forecast soundings show modestly steep midlevel lapse rates and elongated/straight hodographs above around 1-2 km. This suggests isolated hail potential with the strongest storms. Where stronger heating occurs, steep low-level lapse rates will foster isolated strong/damaging gusts as well. ...Central High Plains... Afternoon thunderstorms across the higher terrain are forecast to progress eastward into the lower elevations of the central High Plains during the late afternoon/early evening. Steep low-level lapse rates and high cloud bases will likely support a few stronger gusts as this activity moves eastward into western KS. ..Mosier.. 08/01/2023 Read more