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Issued at 1100 AM HST Fri Aug 01 2025 736 WTPZ42 KNHC 012039 TCDEP2 Tropical Storm Gil Discussion Number 7 NWS National Hurricane Center Miami FL EP072025 1100 AM HST Fri Aug 01 2025 Gil has slightly strengthened over the past few hours. A scatterometer pass from 1710 UTC showed an area of near 50 kt vectors in the northeastern quadrant of the storm. More recent geostationary satellite data shows fragmented convection, with a curved band wrapping around the southern semicircle. The imagery suggests Gil is experiencing a dry air intrusion wrapping around the storm's core. Based on the ASCAT data (accounting for instrument undersampling) and a blend of the latest subjective Dvorak estimates the initial intensity is increased slightly to 60 kt. The initial motion is 290/15 kt. The track forecast reasoning remains unchanged. Gil should continue a west-northwestward motion along the southern periphery of a mid-level ridge for the next few days. As the storm weakens, a turn to the west is forecast around day 4. The NHC track prediction is essentially unchanged from the previous cycle's forecast. Gil is currently crossing a cooling gradient of the sea surface temperatures and nearing the 26 degree Celsius isotherm. Therefore, the storm's chances for any significant strengthening are quickly diminishing. Beyond 12 hours, global models predict increasing shear and a dry and stable airmass will steadily weaken the storm for the remainder of the forecast period. The latest official intensity forecast lies near the various consensus aids. Gil is still expected to become a post-tropical cyclone by the end of weekend. FORECAST POSITIONS AND MAX WINDS INIT 01/2100Z 15.9N 123.3W 60 KT 70 MPH 12H 02/0600Z 16.9N 125.7W 65 KT 75 MPH 24H 02/1800Z 18.4N 129.0W 60 KT 70 MPH 36H 03/0600Z 19.7N 132.1W 55 KT 65 MPH 48H 03/1800Z 20.8N 135.1W 45 KT 50 MPH 60H 04/0600Z 21.6N 137.7W 35 KT 40 MPH...POST-TROPICAL 72H 04/1800Z 22.3N 140.0W 30 KT 35 MPH...POST-TROP/REMNT LOW 96H 05/1800Z 23.2N 145.5W 30 KT 35 MPH...POST-TROP/REMNT LOW 120H 06/1800Z 23.8N 150.5W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Bucci

Issued at 2100 UTC FRI AUG 01 2025 550 FOPZ12 KNHC 012038 PWSEP2 TROPICAL STORM GIL WIND SPEED PROBABILITIES NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072025 2100 UTC FRI AUG 01 2025 AT 2100Z THE CENTER OF TROPICAL STORM GIL WAS LOCATED NEAR LATITUDE 15.9 NORTH...LONGITUDE 123.3 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 60 KTS...70 MPH...110 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 125W 34 44 1(45) X(45) X(45) X(45) X(45) X(45) 20N 125W 34 5 2( 7) X( 7) X( 7) X( 7) X( 7) X( 7) 15N 130W 34 3 2( 5) 1( 6) X( 6) X( 6) X( 6) X( 6) 20N 130W 34 1 21(22) 37(59) X(59) X(59) X(59) X(59) 20N 130W 50 X 1( 1) 13(14) X(14) X(14) X(14) X(14) 20N 130W 64 X X( X) 2( 2) X( 2) X( 2) X( 2) X( 2) 20N 135W 34 X X( X) 6( 6) 29(35) 1(36) X(36) X(36) 20N 135W 50 X X( X) X( X) 8( 8) 1( 9) X( 9) X( 9) 20N 135W 64 X X( X) X( X) 2( 2) X( 2) X( 2) X( 2) 20N 140W 34 X X( X) X( X) 1( 1) 2( 3) 1( 4) X( 4) 25N 145W 34 X X( X) X( X) X( X) X( X) 4( 4) 1( 5) 25N 150W 34 X X( X) X( X) X( X) X( X) X( X) 4( 4) $$ FORECASTER BUCCI

Issued at 1100 AM HST Fri Aug 01 2025 799 WTPZ32 KNHC 012038 TCPEP2 BULLETIN Tropical Storm Gil Advisory Number 7 NWS National Hurricane Center Miami FL EP072025 1100 AM HST Fri Aug 01 2025 ...GIL SLIGHTLY STRENGTHENING... SUMMARY OF 1100 AM HST...2100 UTC...INFORMATION ----------------------------------------------- LOCATION...15.9N 123.3W ABOUT 995 MI...1605 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H PRESENT MOVEMENT...WNW OR 290 DEGREES AT 17 MPH...28 KM/H MINIMUM CENTRAL PRESSURE...993 MB...29.33 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 Tropical Storm Gil was located near latitude 15.9 North, longitude 123.3 West. Gil is moving toward the west-northwest near 17 mph (28 km/h) and this general motion is expected over the next few days. Maximum sustained winds are near 70 mph (110 km/h) with higher gusts. Some slight strengthening is forecast and Gil could become a hurricane later today. Gradual weakening is expected over the weekend. Tropical-storm-force winds extend outward up to 140 miles (220 km) from the center. The estimated minimum central pressure is 993 mb (29.33 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 500 PM HST. $$ Forecaster Bucci

...GIL SLIGHTLY STRENGTHENING... As of 11:00 AM HST Fri Aug 01 the center of Gil was located near 15.9, -123.3 with movement WNW at 17 mph. The minimum central pressure was 993 mb with maximum sustained winds of about 70 mph.

Issued at 2100 UTC FRI AUG 01 2025 106 WTPZ22 KNHC 012038 TCMEP2 TROPICAL STORM GIL FORECAST/ADVISORY NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL EP072025 2100 UTC FRI AUG 01 2025 TROPICAL STORM CENTER LOCATED NEAR 15.9N 123.3W AT 01/2100Z POSITION ACCURATE WITHIN 20 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 290 DEGREES AT 15 KT ESTIMATED MINIMUM CENTRAL PRESSURE 993 MB MAX SUSTAINED WINDS 60 KT WITH GUSTS TO 75 KT. 50 KT....... 50NE 50SE 0SW 50NW. 34 KT.......120NE 120SE 90SW 90NW. 4 M SEAS....300NE 270SE 90SW 120NW. 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 15.9N 123.3W AT 01/2100Z AT 01/1800Z CENTER WAS LOCATED NEAR 15.6N 122.5W FORECAST VALID 02/0600Z 16.9N 125.7W MAX WIND 65 KT...GUSTS 80 KT. 64 KT... 20NE 0SE 0SW 0NW. 50 KT... 60NE 50SE 20SW 50NW. 34 KT...130NE 130SE 90SW 100NW. FORECAST VALID 02/1800Z 18.4N 129.0W MAX WIND 60 KT...GUSTS 75 KT. 50 KT... 40NE 30SE 20SW 30NW. 34 KT...130NE 110SE 80SW 110NW. FORECAST VALID 03/0600Z 19.7N 132.1W MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 40NE 0SE 0SW 20NW. 34 KT...100NE 80SE 60SW 90NW. FORECAST VALID 03/1800Z 20.8N 135.1W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 90NE 60SE 40SW 80NW. FORECAST VALID 04/0600Z 21.6N 137.7W...POST-TROPICAL MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 70NE 0SE 0SW 60NW. FORECAST VALID 04/1800Z 22.3N 140.0W...POST-TROPICAL MAX WIND 30 KT...GUSTS 40 KT. 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 23.2N 145.5W...POST-TROP/REMNT LOW MAX WIND 30 KT...GUSTS 40 KT. OUTLOOK VALID 06/1800Z 23.8N 150.5W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 15.9N 123.3W NEXT ADVISORY AT 02/0300Z $$ FORECASTER BUCCI

No watches are valid as of Fri Aug 1 20:01:01 UTC 2025.

MD 1861 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR FAR SOUTHERN VIRGINIA INTO NORTH CAROLINA AND NORTHERN SOUTH CAROLINA
Mesoscale Discussion 1861 NWS Storm Prediction Center Norman OK 0144 PM CDT Fri Aug 01 2025 Areas affected...Far southern Virginia into North Carolina and northern South Carolina Concerning...Severe potential...Watch unlikely Valid 011844Z - 012045Z Probability of Watch Issuance...5 percent SUMMARY...Thunderstorms emanating off the Blue Ridge Mountains and developing along a cold front will pose a damaging wind threat through early evening. Watch issuance is not expected. DISCUSSION...Thunderstorm development is well underway along the Blue Ridge Mountains amid a combination of diurnal destabilization and increasing ascent due to both lift along an approaching baroclinic zone and modest upslope flow. Additionally, thunderstorms are beginning to slowly intensify along a weak cold front across northern SC where temperatures have warmed into the low 90s. Although deep-layer flow is fairly weak (generally less than 20 knots through 6 km), somewhat uniform ascent along the terrain/front is promoting sufficient convective coverage/spacing to favor multicell clusters with consolidated cold pools. The expectation through early evening is for one or more clusters to emerge off the terrain and propagate south/southeast into the more buoyant air mass across the Carolinas ahead of the primary baroclinic zone. As this occurs, a combination of high PWAT values (well above 2.0 inches) and steepening 0-2 km lapse rates should promote wet downbursts capable of transient strong to severe gusts (mainly 45-65 mph) within the stronger clusters. While wind damage is probable, the poor kinematic environment should limit the overall propensity for severe convection and precludes watch issuance. ..Moore/Smith.. 08/01/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MHX...RAH...ILM...RNK...CAE...GSP... LAT...LON 33687892 33588016 33988178 34288245 34528268 34838282 35118283 35438264 35858221 36408152 37008045 37148005 37177980 37107962 36977939 36807927 36627916 36407912 36177914 35927911 35697897 35517885 35297865 35167840 34977805 34817776 34627758 34487755 34337753 34147757 33917782 33807822 33687892 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 01 2025 Valid 012000Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...20z Update... The forecast largely remains on track. The primary update was to introduce 5% tornado probabilities across portions of northwest SD ahead of a pronounced MCV where initial stages of thunderstorm development are noted in recent GOES/lightning data. Visible imagery shows slowly building cumulus within the southeasterly flow regime ahead of the MCV as temperatures warm into the mid/upper 70s. Forecast soundings suggest this is adequate for surface-based convection, and depict enlarging hodographs later this evening as the nocturnal jet strengthens. While localized, this environment may be somewhat more favorable for tornadoes compared to adjacent portions of SD. Elsewhere, minimal changes are required. 5% wind probabilities were amended slightly across portions of the Carolinas to better reflect recent thunderstorm development/trends. See the previous discussion below as well as MCDs #1860-1862 for additional details. ..Moore.. 08/01/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Aug 01 2025/ ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 01 2025 Valid 012000Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...20z Update... The forecast largely remains on track. The primary update was to introduce 5% tornado probabilities across portions of northwest SD ahead of a pronounced MCV where initial stages of thunderstorm development are noted in recent GOES/lightning data. Visible imagery shows slowly building cumulus within the southeasterly flow regime ahead of the MCV as temperatures warm into the mid/upper 70s. Forecast soundings suggest this is adequate for surface-based convection, and depict enlarging hodographs later this evening as the nocturnal jet strengthens. While localized, this environment may be somewhat more favorable for tornadoes compared to adjacent portions of SD. Elsewhere, minimal changes are required. 5% wind probabilities were amended slightly across portions of the Carolinas to better reflect recent thunderstorm development/trends. See the previous discussion below as well as MCDs #1860-1862 for additional details. ..Moore.. 08/01/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Aug 01 2025/ ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 01 2025 Valid 012000Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...20z Update... The forecast largely remains on track. The primary update was to introduce 5% tornado probabilities across portions of northwest SD ahead of a pronounced MCV where initial stages of thunderstorm development are noted in recent GOES/lightning data. Visible imagery shows slowly building cumulus within the southeasterly flow regime ahead of the MCV as temperatures warm into the mid/upper 70s. Forecast soundings suggest this is adequate for surface-based convection, and depict enlarging hodographs later this evening as the nocturnal jet strengthens. While localized, this environment may be somewhat more favorable for tornadoes compared to adjacent portions of SD. Elsewhere, minimal changes are required. 5% wind probabilities were amended slightly across portions of the Carolinas to better reflect recent thunderstorm development/trends. See the previous discussion below as well as MCDs #1860-1862 for additional details. ..Moore.. 08/01/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Aug 01 2025/ ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 01 2025 Valid 012000Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...20z Update... The forecast largely remains on track. The primary update was to introduce 5% tornado probabilities across portions of northwest SD ahead of a pronounced MCV where initial stages of thunderstorm development are noted in recent GOES/lightning data. Visible imagery shows slowly building cumulus within the southeasterly flow regime ahead of the MCV as temperatures warm into the mid/upper 70s. Forecast soundings suggest this is adequate for surface-based convection, and depict enlarging hodographs later this evening as the nocturnal jet strengthens. While localized, this environment may be somewhat more favorable for tornadoes compared to adjacent portions of SD. Elsewhere, minimal changes are required. 5% wind probabilities were amended slightly across portions of the Carolinas to better reflect recent thunderstorm development/trends. See the previous discussion below as well as MCDs #1860-1862 for additional details. ..Moore.. 08/01/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Aug 01 2025/ ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 01 2025 Valid 012000Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...20z Update... The forecast largely remains on track. The primary update was to introduce 5% tornado probabilities across portions of northwest SD ahead of a pronounced MCV where initial stages of thunderstorm development are noted in recent GOES/lightning data. Visible imagery shows slowly building cumulus within the southeasterly flow regime ahead of the MCV as temperatures warm into the mid/upper 70s. Forecast soundings suggest this is adequate for surface-based convection, and depict enlarging hodographs later this evening as the nocturnal jet strengthens. While localized, this environment may be somewhat more favorable for tornadoes compared to adjacent portions of SD. Elsewhere, minimal changes are required. 5% wind probabilities were amended slightly across portions of the Carolinas to better reflect recent thunderstorm development/trends. See the previous discussion below as well as MCDs #1860-1862 for additional details. ..Moore.. 08/01/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Aug 01 2025/ ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 01 2025 Valid 012000Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...20z Update... The forecast largely remains on track. The primary update was to introduce 5% tornado probabilities across portions of northwest SD ahead of a pronounced MCV where initial stages of thunderstorm development are noted in recent GOES/lightning data. Visible imagery shows slowly building cumulus within the southeasterly flow regime ahead of the MCV as temperatures warm into the mid/upper 70s. Forecast soundings suggest this is adequate for surface-based convection, and depict enlarging hodographs later this evening as the nocturnal jet strengthens. While localized, this environment may be somewhat more favorable for tornadoes compared to adjacent portions of SD. Elsewhere, minimal changes are required. 5% wind probabilities were amended slightly across portions of the Carolinas to better reflect recent thunderstorm development/trends. See the previous discussion below as well as MCDs #1860-1862 for additional details. ..Moore.. 08/01/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Aug 01 2025/ ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 01 2025 Valid 012000Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...20z Update... The forecast largely remains on track. The primary update was to introduce 5% tornado probabilities across portions of northwest SD ahead of a pronounced MCV where initial stages of thunderstorm development are noted in recent GOES/lightning data. Visible imagery shows slowly building cumulus within the southeasterly flow regime ahead of the MCV as temperatures warm into the mid/upper 70s. Forecast soundings suggest this is adequate for surface-based convection, and depict enlarging hodographs later this evening as the nocturnal jet strengthens. While localized, this environment may be somewhat more favorable for tornadoes compared to adjacent portions of SD. Elsewhere, minimal changes are required. 5% wind probabilities were amended slightly across portions of the Carolinas to better reflect recent thunderstorm development/trends. See the previous discussion below as well as MCDs #1860-1862 for additional details. ..Moore.. 08/01/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Aug 01 2025/ ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 01 2025 Valid 012000Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...20z Update... The forecast largely remains on track. The primary update was to introduce 5% tornado probabilities across portions of northwest SD ahead of a pronounced MCV where initial stages of thunderstorm development are noted in recent GOES/lightning data. Visible imagery shows slowly building cumulus within the southeasterly flow regime ahead of the MCV as temperatures warm into the mid/upper 70s. Forecast soundings suggest this is adequate for surface-based convection, and depict enlarging hodographs later this evening as the nocturnal jet strengthens. While localized, this environment may be somewhat more favorable for tornadoes compared to adjacent portions of SD. Elsewhere, minimal changes are required. 5% wind probabilities were amended slightly across portions of the Carolinas to better reflect recent thunderstorm development/trends. See the previous discussion below as well as MCDs #1860-1862 for additional details. ..Moore.. 08/01/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Aug 01 2025/ ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 01 2025 Valid 012000Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...20z Update... The forecast largely remains on track. The primary update was to introduce 5% tornado probabilities across portions of northwest SD ahead of a pronounced MCV where initial stages of thunderstorm development are noted in recent GOES/lightning data. Visible imagery shows slowly building cumulus within the southeasterly flow regime ahead of the MCV as temperatures warm into the mid/upper 70s. Forecast soundings suggest this is adequate for surface-based convection, and depict enlarging hodographs later this evening as the nocturnal jet strengthens. While localized, this environment may be somewhat more favorable for tornadoes compared to adjacent portions of SD. Elsewhere, minimal changes are required. 5% wind probabilities were amended slightly across portions of the Carolinas to better reflect recent thunderstorm development/trends. See the previous discussion below as well as MCDs #1860-1862 for additional details. ..Moore.. 08/01/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Aug 01 2025/ ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 01 2025 Valid 012000Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...20z Update... The forecast largely remains on track. The primary update was to introduce 5% tornado probabilities across portions of northwest SD ahead of a pronounced MCV where initial stages of thunderstorm development are noted in recent GOES/lightning data. Visible imagery shows slowly building cumulus within the southeasterly flow regime ahead of the MCV as temperatures warm into the mid/upper 70s. Forecast soundings suggest this is adequate for surface-based convection, and depict enlarging hodographs later this evening as the nocturnal jet strengthens. While localized, this environment may be somewhat more favorable for tornadoes compared to adjacent portions of SD. Elsewhere, minimal changes are required. 5% wind probabilities were amended slightly across portions of the Carolinas to better reflect recent thunderstorm development/trends. See the previous discussion below as well as MCDs #1860-1862 for additional details. ..Moore.. 08/01/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Aug 01 2025/ ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 01 2025 Valid 012000Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL HIGH PLAINS INTO WESTERN SOUTH DAKOTA... ...SUMMARY... Scattered severe thunderstorms are possible across parts of the High Plains this afternoon and evening. Large to very large hail, a couple of tornadoes, and severe gusts are possible. ...20z Update... The forecast largely remains on track. The primary update was to introduce 5% tornado probabilities across portions of northwest SD ahead of a pronounced MCV where initial stages of thunderstorm development are noted in recent GOES/lightning data. Visible imagery shows slowly building cumulus within the southeasterly flow regime ahead of the MCV as temperatures warm into the mid/upper 70s. Forecast soundings suggest this is adequate for surface-based convection, and depict enlarging hodographs later this evening as the nocturnal jet strengthens. While localized, this environment may be somewhat more favorable for tornadoes compared to adjacent portions of SD. Elsewhere, minimal changes are required. 5% wind probabilities were amended slightly across portions of the Carolinas to better reflect recent thunderstorm development/trends. See the previous discussion below as well as MCDs #1860-1862 for additional details. ..Moore.. 08/01/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Aug 01 2025/ ...High Plains... Water-vapor imagery late this morning shows a few disturbances undercutting an upper ridge currently over the High Plains/Alberta. An MCV is slowly moving eastward near the MT/WY/SD/ND border, a more pronounced upper trough will remain over the northern Rockies and adjacent high plains of MT, and a more subtle disturbance will move east-northeastward across the central Rockies. A residual frontal zone draped generally south-north abutting the higher terrain is providing a focus for richer moisture east of this boundary over the High Plains. Surface dewpoints will likely range from the mid 50s to the lower 60s across much of the Slight Risk. A belt of slightly stronger westerly upper flow is forecast across the central High Plains which will act to elongate hodographs. Additionally, a plume of steep 700-500 mb lapse rates (7.5 to 9 deg C/km) will contribute to MLCAPE 2000-3000 by mid-late afternoon. The aforementioned low-amplitude disturbance over the central Rockies coupled with low-level upslope flow/orographic effects will result in initial thunderstorm development over the high terrain and the Cheyenne Ridge. The best overlap between buoyancy and shear is expected from western SD into northeast CO/WY/NE Panhandle border region. Model ensemble data suggest a few favored corridors for severe may result. The most notable area may focus near the Cheyenne Ridge and adjacent northeast CO where supercell potential appears greatest. Large to very large hail and a tornado or two are possible with this activity before gradually transitioning to primarily a risk for severe gusts. One other area of interest is across northwest SD, where an MCV moving slowly into the region could result in a focused area of thunderstorms. Increased low-level convergence and low-level vertical shear near this MCV could lead to a greater threat for all severe hazards, including large hail and perhaps a brief tornado or two. ...Carolinas into Georgia-Alabama-Mississippi... A seasonably moist airmass was sampled by 12 UTC area raobs this morning (near 16 g/kg lowest 100-mb mean mixing ratio). Visible-satellite imagery shows extensive low cloud cover across central and eastern NC near and behind the wind shift/cold front. Farther west, initial cumulus field development is noted over the southern Appalachians where strong heating is occurring and farther south/southeast over the Piedmont and to the coastal plain. As temperatures continue to warm through early afternoon, erosion of convective inhibition will result in scattered storms favoring the higher terrain and eventually near the wind shift. High PW (2 inches or greater) and diurnally steepened surface to 1.5 km lapse rates will support a risk for wet microbursts with the more intense water-loaded downdrafts. Localized gusts 50-65 mph are possible and scattered pockets of wind damage may result. Read more