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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0342 PM CDT Thu Jul 25 2024 Valid 271200Z - 021200Z Fire weather concerns will be focused in parts of the Great Basin and northern Rockies during the extended period. A weak tropical disturbance will move into the Great Basin and eventually the central/northern Rockies this weekend. A second upper-level trough will move into the Northwest early next week and impact the northern Rockies into Wednesday. ...Wind/RH... Strong surface winds are expected in parts of the southern Great Basin on Saturday and perhaps Sunday. Critical fire weather is most likely on Saturday given the stronger mid-level winds and a deeper surface trough. Given the recent lighting activity in the area, fire weather activity could increase with the stronger winds and low RH. Sunday will be similarly dry, but winds will tend to be lighter as the upper trough loses amplitude and the surface pattern becomes more diffuse. Another increase in winds is possible on Monday with the second trough moving into the northern Great Basin. With lower confidence in the upper-level pattern this far in advance, no highlights will be added. Dry and windy conditions appear probable in parts of Wyoming/Montana with the approach of the second trough on Tuesday. As mentioned, the timing intensity of upper/surface features are uncertain enough to preclude highlights. However, with the amount of recent lightning activity, these areas will need to be monitored for an increase in critical fire weather potential. ...Dry Thunderstorms... A tropical disturbance will phase with the mean trough over the Northwest this weekend. This disturbance will move into portions of central and northern Nevada before losing amplitude as it progresses into the northern/central Rockies vicinity. Isolated dry thunderstorm activity is possible in parts of Idaho, western Wyoming, and southwestern Montana on Saturday. Some activity is possible on Sunday as well, but coverage should be less. Thunderstorms will again be possible in the northern Rockies with the second upper-level trough moving into the region Tuesday into Wednesday. Confidence is only low to moderate given the high amount of variability with regard to the upper-level pattern in recent model runs. ..Wendt.. 07/25/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

Hamilton County pastures were not growing back and animals were suffering amid the drought. Cattle could not be rotated among pastures as usual, according to a farmer near Chattanooga. The warm season grasses have not received enough precipitation to continue growing and provide grazing for cattle. Consequently, cattle were kept in a confined space and were fed hay. The cattle would not normally receive hay until the winter. The farmer brought water to the pigs so they could cool off. Typically, they would have wallows to get in and cool down, but the lack of rain meant that the farmer had to haul water to the pigs so the animals would create wallows. Even the creek has gone dry so there was no natural spring water for the animals to drink. Local 3 News (Chattanooga, Tenn.), July 20, 2024

5-Day Uncertainty Track last updated Thu, 25 Jul 2024 20:36:34 GMT


Wind Speed Probabilities last updated Thu, 25 Jul 2024 21:22:43 GMT

Issued at 200 PM PDT Thu Jul 25 2024 497 WTPZ42 KNHC 252035 TCDEP2 Tropical Storm Bud Discussion Number 6 NWS National Hurricane Center Miami FL EP022024 200 PM PDT Thu Jul 25 2024 Satellite imagery indicates that Bud continues to maintain its intensity. The vertical wind shear has clearly weakened over the past day or so, as a pair of recent 1659 and 1753 UTC ASCAT passes indicate that the center is well embedded underneath the central convective area. Based on the ASCAT data and the latest satellite intensity estimates, the intensity is held at 50 kt for this advisory. A low- to mid-level ridge located to the north of Bud will steer the cyclone generally westward at a similar forward speed for the next 24 h. As the cyclone weakens and becomes shallower, it should turn towards the west-southwest and decelerate. The new NHC forecast has again been adjusted a bit to the north and faster to the west, following the trend in the guidance, but the NHC forecast is still to the southeast of the latest consensus models. As Bud traverses sea-surface temperatures of around 27C over the next day or two, the vertical wind shear should remain relatively low. The SHIPS guidance suggests that Bud is moving into a stable airmass, which should cause the cyclone to begin weakening by tonight or on Friday. No significant changes have been made to the previous NHC intensity forecast, which still lies near the intensity consensus, above the weaker dynamical model guidance, and below the stronger statistical guidance. Bud is forecast to become a remnant low on Saturday and dissipate on Sunday. FORECAST POSITIONS AND MAX WINDS INIT 25/2100Z 18.4N 117.0W 50 KT 60 MPH 12H 26/0600Z 18.6N 118.5W 45 KT 50 MPH 24H 26/1800Z 18.7N 120.2W 40 KT 45 MPH 36H 27/0600Z 18.6N 121.8W 35 KT 40 MPH 48H 27/1800Z 18.4N 122.9W 30 KT 35 MPH...POST-TROP/REMNT LOW 60H 28/0600Z 18.1N 124.1W 25 KT 30 MPH...POST-TROP/REMNT LOW 72H 28/1800Z...DISSIPATED $$ Forecaster Hagen/Berg

Issued at 200 PM PDT Thu Jul 25 2024 000 WTPZ32 KNHC 252034 TCPEP2 BULLETIN Tropical Storm Bud Advisory Number 6 NWS National Hurricane Center Miami FL EP022024 200 PM PDT Thu Jul 25 2024 ...BUD CONTINUES WESTWARD WITH LITTLE CHANGE IN STRENGTH... SUMMARY OF 200 PM PDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...18.4N 117.0W ABOUT 555 MI...890 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H PRESENT MOVEMENT...W OR 280 DEGREES AT 14 MPH...22 KM/H MINIMUM CENTRAL PRESSURE...1000 MB...29.53 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 200 PM PDT (2100 UTC), the center of Tropical Storm Bud was located near latitude 18.4 North, longitude 117.0 West. Bud is moving toward the west near 14 mph (22 km/h), and this motion is expected to continue through Friday. A turn to the west-southwest at a slower forward speed is expected Friday night into Saturday. Maximum sustained winds are near 60 mph (95 km/h) with higher gusts. Steady weakening is forecast to begin tonight or Friday, and Bud is expected to become a remnant low on Saturday and dissipate by Sunday. Tropical-storm-force winds extend outward up to 35 miles (55 km) from the center. The estimated minimum central pressure is 1000 mb (29.53 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 800 PM PDT. $$ Forecaster Hagen/Berg

...BUD CONTINUES WESTWARD WITH LITTLE CHANGE IN STRENGTH... As of 2:00 PM PDT Thu Jul 25 the center of Bud was located near 18.4, -117.0 with movement W at 14 mph. The minimum central pressure was 1000 mb with maximum sustained winds of about 60 mph.

Issued at 2100 UTC THU JUL 25 2024 000 FOPZ12 KNHC 252034 PWSEP2 TROPICAL STORM BUD WIND SPEED PROBABILITIES NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL EP022024 2100 UTC THU JUL 25 2024 AT 2100Z THE CENTER OF TROPICAL STORM BUD WAS LOCATED NEAR LATITUDE 18.4 NORTH...LONGITUDE 117.0 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 50 KTS...60 MPH...95 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 THU 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 THU 06Z FRI 18Z FRI 06Z SAT 18Z SAT 18Z SUN 18Z MON PERIODS TO TO TO TO TO TO TO 06Z FRI 18Z FRI 06Z SAT 18Z SAT 18Z SUN 18Z MON 18Z TUE FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 20N 120W 34 X 6( 6) 2( 8) X( 8) X( 8) X( 8) X( 8) $$ FORECASTER HAGEN/BERG

Issued at 2100 UTC THU JUL 25 2024 000 WTPZ22 KNHC 252034 TCMEP2 TROPICAL STORM BUD FORECAST/ADVISORY NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL EP022024 2100 UTC THU JUL 25 2024 TROPICAL STORM CENTER LOCATED NEAR 18.4N 117.0W AT 25/2100Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST OR 280 DEGREES AT 12 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1000 MB MAX SUSTAINED WINDS 50 KT WITH GUSTS TO 60 KT. 50 KT....... 0NE 0SE 0SW 15NW. 34 KT....... 30NE 30SE 30SW 30NW. 12 FT SEAS.. 30NE 30SE 45SW 45NW. 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 18.4N 117.0W AT 25/2100Z AT 25/1800Z CENTER WAS LOCATED NEAR 18.3N 116.5W FORECAST VALID 26/0600Z 18.6N 118.5W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 30NE 30SE 30SW 30NW. FORECAST VALID 26/1800Z 18.7N 120.2W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 30NE 20SE 30SW 30NW. FORECAST VALID 27/0600Z 18.6N 121.8W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 30NE 0SE 0SW 30NW. FORECAST VALID 27/1800Z 18.4N 122.9W...POST-TROP/REMNT LOW MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 28/0600Z 18.1N 124.1W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 28/1800Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 18.4N 117.0W NEXT ADVISORY AT 26/0300Z $$ FORECASTER HAGEN/BERG

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Thu Jul 25 2024 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF CENTRAL AND NORTHEASTERN MONTANA...PORTIONS OF NORTHEASTERN NEVADA AND NORTHWESTERN UTAH... ...SUMMARY... Scattered severe thunderstorms capable of 60-75 mph gusts are forecast across portions of central/northeast Montana and northeastern Nevada/northwestern Utah late this afternoon into the evening. ...20z Update... A Slight Risk was introduced across northeastern Nevada and northwestern Utah, where scattered to numerous thunderstorms posing a risk of severe gusts should develop by the afternoon. Recent runs of the HRRR, as well as guidance from the 12Z HREF, continue to indicate the possibility of convection consolidating along outflow and surging northeast into northwestern Utah through the evening. Forecast sounding profiles support risk for severe gusts, with steep low to mid-level lapse rates and characteristic inverted-v indicative of large dew point spreads. This will support downward momentum transport of severe wind up to 60-70 mph, especially where outflow storms can consolidate along outflow. The Marginal Risk across Arizona was expanded westward into far southwestern Arizona to encompass potential for a cluster of thunderstorms to push westward by late evening. Thunderstorm activity is expected to continue across the high country before a gradual shift into the low deserts by the evening. Some consideration was given to a Slight Risk in this area but uncertainty remains in storm coverage along the Mogollon Rim and whether strong outflow will develop and move southwestward into the low terrain this evening. Otherwise, the eastern US Marginal Risk areas remain unchanged. Storms capable of locally damaging winds will continue to be possible through the afternoon and evening. ..Thornton/Smith.. 07/25/2024 .PREV DISCUSSION... /ISSUED 1131 AM CDT Thu Jul 25 2024/ ...Montana/Northern Rockies to Great Basin... Water-vapor imagery this morning shows an upper-level trough moving east from British Columbia toward Alberta/Saskatchewan, with strengthening cyclonic westerlies overspreading the northern Rockies/Montana. Model guidance continues to indicate scattered thunderstorm development initiating off the higher terrain this afternoon, and in advance of a cold front across central Montana. Forecast soundings shows large to very large surface temperature-dewpoint spreads (40-60 F) later this afternoon. A downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to severe-caliber wind gusts in consolidating outflows, as convection spreads eastward into this evening toward eastern Montana and possibly western North Dakota. Farther south over the Great Basin, model guidance appears to be trending towards greater storm coverage (numerous) and associated ability for storm outflow. The 12 UTC HREF in particular (and recent HRRR runs) shows a potential corridor of outflow surging convection from northeast NV into northwest and northern UT during the 23-04 UTC period. Some consideration for a Slight Risk was given but uncertainty precludes an upgrade at this time. ...Arizona... Lingering early day outflow/cloud cover via yesterday's relatively active convection should generally abate by afternoon. As the boundary layer diurnally warms and destabilizes, thunderstorms are again likely to initiate across the Mogollon Rim and adjacent mountains of southwest New Mexico this afternoon. Given the position and movement of the mid-level high, somewhat stronger (around 15 kt) northeasterly steering flow will remain focused across southeast into adjacent portions of central Arizona. Severe gusts will be possible later this afternoon into the mid-late evening as storms progress south-southwestward across the lower deserts of central and southern AZ. ...Carolinas/Mid-Atlantic States... Midday visible-satellite imagery shows and extensive cloud shield across much of NC into the southern half of VA. The 12 UTC GSO raob featuring poor lapse rates and meager buoyancy contrasted with the MHX raob (2000 J/kg MLCAPE) and a much more moisture-rich airmass. Thinner cloud cover near the coast will aid in widely scattered storms developing this afternoon largely removed from the southern fringe of large-scale troughing over the Mid-Atlantic states/Northeast. An isolated risk for locally severe gusts may develop for several hours this afternoon into the early evening. Farther north, breaks and thinning of cloud cover will promote stronger heating across northern VA into the northern half of the Chesapeake Bay vicinity than areas farther south. Widely scattered storms are forecast to develop per the latest 12 UTC HREF guidance within this corridor by mid-late afternoon. A belt of 40-50 kt southwesterly 500-mb flow may enhance storm vigor, and a few downdrafts may yield a risk for isolated 45-60 mph gusts capable of localized damage. ...Upper Texas Coast and Southwest Louisiana... Extensive showers and some thunderstorms are ongoing along the Texas coast early today. Influenced by a weak mid-level disturbance, some guidance suggests that a strengthening of low-level winds/shear may occur. However, mid-level winds will remain weak, while the aforementioned convection should considerably limit destabilization inland. These factors seem likely to minimize the potential for anything beyond a very weak/transient circulation. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Thu Jul 25 2024 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF CENTRAL AND NORTHEASTERN MONTANA...PORTIONS OF NORTHEASTERN NEVADA AND NORTHWESTERN UTAH... ...SUMMARY... Scattered severe thunderstorms capable of 60-75 mph gusts are forecast across portions of central/northeast Montana and northeastern Nevada/northwestern Utah late this afternoon into the evening. ...20z Update... A Slight Risk was introduced across northeastern Nevada and northwestern Utah, where scattered to numerous thunderstorms posing a risk of severe gusts should develop by the afternoon. Recent runs of the HRRR, as well as guidance from the 12Z HREF, continue to indicate the possibility of convection consolidating along outflow and surging northeast into northwestern Utah through the evening. Forecast sounding profiles support risk for severe gusts, with steep low to mid-level lapse rates and characteristic inverted-v indicative of large dew point spreads. This will support downward momentum transport of severe wind up to 60-70 mph, especially where outflow storms can consolidate along outflow. The Marginal Risk across Arizona was expanded westward into far southwestern Arizona to encompass potential for a cluster of thunderstorms to push westward by late evening. Thunderstorm activity is expected to continue across the high country before a gradual shift into the low deserts by the evening. Some consideration was given to a Slight Risk in this area but uncertainty remains in storm coverage along the Mogollon Rim and whether strong outflow will develop and move southwestward into the low terrain this evening. Otherwise, the eastern US Marginal Risk areas remain unchanged. Storms capable of locally damaging winds will continue to be possible through the afternoon and evening. ..Thornton/Smith.. 07/25/2024 .PREV DISCUSSION... /ISSUED 1131 AM CDT Thu Jul 25 2024/ ...Montana/Northern Rockies to Great Basin... Water-vapor imagery this morning shows an upper-level trough moving east from British Columbia toward Alberta/Saskatchewan, with strengthening cyclonic westerlies overspreading the northern Rockies/Montana. Model guidance continues to indicate scattered thunderstorm development initiating off the higher terrain this afternoon, and in advance of a cold front across central Montana. Forecast soundings shows large to very large surface temperature-dewpoint spreads (40-60 F) later this afternoon. A downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to severe-caliber wind gusts in consolidating outflows, as convection spreads eastward into this evening toward eastern Montana and possibly western North Dakota. Farther south over the Great Basin, model guidance appears to be trending towards greater storm coverage (numerous) and associated ability for storm outflow. The 12 UTC HREF in particular (and recent HRRR runs) shows a potential corridor of outflow surging convection from northeast NV into northwest and northern UT during the 23-04 UTC period. Some consideration for a Slight Risk was given but uncertainty precludes an upgrade at this time. ...Arizona... Lingering early day outflow/cloud cover via yesterday's relatively active convection should generally abate by afternoon. As the boundary layer diurnally warms and destabilizes, thunderstorms are again likely to initiate across the Mogollon Rim and adjacent mountains of southwest New Mexico this afternoon. Given the position and movement of the mid-level high, somewhat stronger (around 15 kt) northeasterly steering flow will remain focused across southeast into adjacent portions of central Arizona. Severe gusts will be possible later this afternoon into the mid-late evening as storms progress south-southwestward across the lower deserts of central and southern AZ. ...Carolinas/Mid-Atlantic States... Midday visible-satellite imagery shows and extensive cloud shield across much of NC into the southern half of VA. The 12 UTC GSO raob featuring poor lapse rates and meager buoyancy contrasted with the MHX raob (2000 J/kg MLCAPE) and a much more moisture-rich airmass. Thinner cloud cover near the coast will aid in widely scattered storms developing this afternoon largely removed from the southern fringe of large-scale troughing over the Mid-Atlantic states/Northeast. An isolated risk for locally severe gusts may develop for several hours this afternoon into the early evening. Farther north, breaks and thinning of cloud cover will promote stronger heating across northern VA into the northern half of the Chesapeake Bay vicinity than areas farther south. Widely scattered storms are forecast to develop per the latest 12 UTC HREF guidance within this corridor by mid-late afternoon. A belt of 40-50 kt southwesterly 500-mb flow may enhance storm vigor, and a few downdrafts may yield a risk for isolated 45-60 mph gusts capable of localized damage. ...Upper Texas Coast and Southwest Louisiana... Extensive showers and some thunderstorms are ongoing along the Texas coast early today. Influenced by a weak mid-level disturbance, some guidance suggests that a strengthening of low-level winds/shear may occur. However, mid-level winds will remain weak, while the aforementioned convection should considerably limit destabilization inland. These factors seem likely to minimize the potential for anything beyond a very weak/transient circulation. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Thu Jul 25 2024 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF CENTRAL AND NORTHEASTERN MONTANA...PORTIONS OF NORTHEASTERN NEVADA AND NORTHWESTERN UTAH... ...SUMMARY... Scattered severe thunderstorms capable of 60-75 mph gusts are forecast across portions of central/northeast Montana and northeastern Nevada/northwestern Utah late this afternoon into the evening. ...20z Update... A Slight Risk was introduced across northeastern Nevada and northwestern Utah, where scattered to numerous thunderstorms posing a risk of severe gusts should develop by the afternoon. Recent runs of the HRRR, as well as guidance from the 12Z HREF, continue to indicate the possibility of convection consolidating along outflow and surging northeast into northwestern Utah through the evening. Forecast sounding profiles support risk for severe gusts, with steep low to mid-level lapse rates and characteristic inverted-v indicative of large dew point spreads. This will support downward momentum transport of severe wind up to 60-70 mph, especially where outflow storms can consolidate along outflow. The Marginal Risk across Arizona was expanded westward into far southwestern Arizona to encompass potential for a cluster of thunderstorms to push westward by late evening. Thunderstorm activity is expected to continue across the high country before a gradual shift into the low deserts by the evening. Some consideration was given to a Slight Risk in this area but uncertainty remains in storm coverage along the Mogollon Rim and whether strong outflow will develop and move southwestward into the low terrain this evening. Otherwise, the eastern US Marginal Risk areas remain unchanged. Storms capable of locally damaging winds will continue to be possible through the afternoon and evening. ..Thornton/Smith.. 07/25/2024 .PREV DISCUSSION... /ISSUED 1131 AM CDT Thu Jul 25 2024/ ...Montana/Northern Rockies to Great Basin... Water-vapor imagery this morning shows an upper-level trough moving east from British Columbia toward Alberta/Saskatchewan, with strengthening cyclonic westerlies overspreading the northern Rockies/Montana. Model guidance continues to indicate scattered thunderstorm development initiating off the higher terrain this afternoon, and in advance of a cold front across central Montana. Forecast soundings shows large to very large surface temperature-dewpoint spreads (40-60 F) later this afternoon. A downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to severe-caliber wind gusts in consolidating outflows, as convection spreads eastward into this evening toward eastern Montana and possibly western North Dakota. Farther south over the Great Basin, model guidance appears to be trending towards greater storm coverage (numerous) and associated ability for storm outflow. The 12 UTC HREF in particular (and recent HRRR runs) shows a potential corridor of outflow surging convection from northeast NV into northwest and northern UT during the 23-04 UTC period. Some consideration for a Slight Risk was given but uncertainty precludes an upgrade at this time. ...Arizona... Lingering early day outflow/cloud cover via yesterday's relatively active convection should generally abate by afternoon. As the boundary layer diurnally warms and destabilizes, thunderstorms are again likely to initiate across the Mogollon Rim and adjacent mountains of southwest New Mexico this afternoon. Given the position and movement of the mid-level high, somewhat stronger (around 15 kt) northeasterly steering flow will remain focused across southeast into adjacent portions of central Arizona. Severe gusts will be possible later this afternoon into the mid-late evening as storms progress south-southwestward across the lower deserts of central and southern AZ. ...Carolinas/Mid-Atlantic States... Midday visible-satellite imagery shows and extensive cloud shield across much of NC into the southern half of VA. The 12 UTC GSO raob featuring poor lapse rates and meager buoyancy contrasted with the MHX raob (2000 J/kg MLCAPE) and a much more moisture-rich airmass. Thinner cloud cover near the coast will aid in widely scattered storms developing this afternoon largely removed from the southern fringe of large-scale troughing over the Mid-Atlantic states/Northeast. An isolated risk for locally severe gusts may develop for several hours this afternoon into the early evening. Farther north, breaks and thinning of cloud cover will promote stronger heating across northern VA into the northern half of the Chesapeake Bay vicinity than areas farther south. Widely scattered storms are forecast to develop per the latest 12 UTC HREF guidance within this corridor by mid-late afternoon. A belt of 40-50 kt southwesterly 500-mb flow may enhance storm vigor, and a few downdrafts may yield a risk for isolated 45-60 mph gusts capable of localized damage. ...Upper Texas Coast and Southwest Louisiana... Extensive showers and some thunderstorms are ongoing along the Texas coast early today. Influenced by a weak mid-level disturbance, some guidance suggests that a strengthening of low-level winds/shear may occur. However, mid-level winds will remain weak, while the aforementioned convection should considerably limit destabilization inland. These factors seem likely to minimize the potential for anything beyond a very weak/transient circulation. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Thu Jul 25 2024 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF CENTRAL AND NORTHEASTERN MONTANA...PORTIONS OF NORTHEASTERN NEVADA AND NORTHWESTERN UTAH... ...SUMMARY... Scattered severe thunderstorms capable of 60-75 mph gusts are forecast across portions of central/northeast Montana and northeastern Nevada/northwestern Utah late this afternoon into the evening. ...20z Update... A Slight Risk was introduced across northeastern Nevada and northwestern Utah, where scattered to numerous thunderstorms posing a risk of severe gusts should develop by the afternoon. Recent runs of the HRRR, as well as guidance from the 12Z HREF, continue to indicate the possibility of convection consolidating along outflow and surging northeast into northwestern Utah through the evening. Forecast sounding profiles support risk for severe gusts, with steep low to mid-level lapse rates and characteristic inverted-v indicative of large dew point spreads. This will support downward momentum transport of severe wind up to 60-70 mph, especially where outflow storms can consolidate along outflow. The Marginal Risk across Arizona was expanded westward into far southwestern Arizona to encompass potential for a cluster of thunderstorms to push westward by late evening. Thunderstorm activity is expected to continue across the high country before a gradual shift into the low deserts by the evening. Some consideration was given to a Slight Risk in this area but uncertainty remains in storm coverage along the Mogollon Rim and whether strong outflow will develop and move southwestward into the low terrain this evening. Otherwise, the eastern US Marginal Risk areas remain unchanged. Storms capable of locally damaging winds will continue to be possible through the afternoon and evening. ..Thornton/Smith.. 07/25/2024 .PREV DISCUSSION... /ISSUED 1131 AM CDT Thu Jul 25 2024/ ...Montana/Northern Rockies to Great Basin... Water-vapor imagery this morning shows an upper-level trough moving east from British Columbia toward Alberta/Saskatchewan, with strengthening cyclonic westerlies overspreading the northern Rockies/Montana. Model guidance continues to indicate scattered thunderstorm development initiating off the higher terrain this afternoon, and in advance of a cold front across central Montana. Forecast soundings shows large to very large surface temperature-dewpoint spreads (40-60 F) later this afternoon. A downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to severe-caliber wind gusts in consolidating outflows, as convection spreads eastward into this evening toward eastern Montana and possibly western North Dakota. Farther south over the Great Basin, model guidance appears to be trending towards greater storm coverage (numerous) and associated ability for storm outflow. The 12 UTC HREF in particular (and recent HRRR runs) shows a potential corridor of outflow surging convection from northeast NV into northwest and northern UT during the 23-04 UTC period. Some consideration for a Slight Risk was given but uncertainty precludes an upgrade at this time. ...Arizona... Lingering early day outflow/cloud cover via yesterday's relatively active convection should generally abate by afternoon. As the boundary layer diurnally warms and destabilizes, thunderstorms are again likely to initiate across the Mogollon Rim and adjacent mountains of southwest New Mexico this afternoon. Given the position and movement of the mid-level high, somewhat stronger (around 15 kt) northeasterly steering flow will remain focused across southeast into adjacent portions of central Arizona. Severe gusts will be possible later this afternoon into the mid-late evening as storms progress south-southwestward across the lower deserts of central and southern AZ. ...Carolinas/Mid-Atlantic States... Midday visible-satellite imagery shows and extensive cloud shield across much of NC into the southern half of VA. The 12 UTC GSO raob featuring poor lapse rates and meager buoyancy contrasted with the MHX raob (2000 J/kg MLCAPE) and a much more moisture-rich airmass. Thinner cloud cover near the coast will aid in widely scattered storms developing this afternoon largely removed from the southern fringe of large-scale troughing over the Mid-Atlantic states/Northeast. An isolated risk for locally severe gusts may develop for several hours this afternoon into the early evening. Farther north, breaks and thinning of cloud cover will promote stronger heating across northern VA into the northern half of the Chesapeake Bay vicinity than areas farther south. Widely scattered storms are forecast to develop per the latest 12 UTC HREF guidance within this corridor by mid-late afternoon. A belt of 40-50 kt southwesterly 500-mb flow may enhance storm vigor, and a few downdrafts may yield a risk for isolated 45-60 mph gusts capable of localized damage. ...Upper Texas Coast and Southwest Louisiana... Extensive showers and some thunderstorms are ongoing along the Texas coast early today. Influenced by a weak mid-level disturbance, some guidance suggests that a strengthening of low-level winds/shear may occur. However, mid-level winds will remain weak, while the aforementioned convection should considerably limit destabilization inland. These factors seem likely to minimize the potential for anything beyond a very weak/transient circulation. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Thu Jul 25 2024 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF CENTRAL AND NORTHEASTERN MONTANA...PORTIONS OF NORTHEASTERN NEVADA AND NORTHWESTERN UTAH... ...SUMMARY... Scattered severe thunderstorms capable of 60-75 mph gusts are forecast across portions of central/northeast Montana and northeastern Nevada/northwestern Utah late this afternoon into the evening. ...20z Update... A Slight Risk was introduced across northeastern Nevada and northwestern Utah, where scattered to numerous thunderstorms posing a risk of severe gusts should develop by the afternoon. Recent runs of the HRRR, as well as guidance from the 12Z HREF, continue to indicate the possibility of convection consolidating along outflow and surging northeast into northwestern Utah through the evening. Forecast sounding profiles support risk for severe gusts, with steep low to mid-level lapse rates and characteristic inverted-v indicative of large dew point spreads. This will support downward momentum transport of severe wind up to 60-70 mph, especially where outflow storms can consolidate along outflow. The Marginal Risk across Arizona was expanded westward into far southwestern Arizona to encompass potential for a cluster of thunderstorms to push westward by late evening. Thunderstorm activity is expected to continue across the high country before a gradual shift into the low deserts by the evening. Some consideration was given to a Slight Risk in this area but uncertainty remains in storm coverage along the Mogollon Rim and whether strong outflow will develop and move southwestward into the low terrain this evening. Otherwise, the eastern US Marginal Risk areas remain unchanged. Storms capable of locally damaging winds will continue to be possible through the afternoon and evening. ..Thornton/Smith.. 07/25/2024 .PREV DISCUSSION... /ISSUED 1131 AM CDT Thu Jul 25 2024/ ...Montana/Northern Rockies to Great Basin... Water-vapor imagery this morning shows an upper-level trough moving east from British Columbia toward Alberta/Saskatchewan, with strengthening cyclonic westerlies overspreading the northern Rockies/Montana. Model guidance continues to indicate scattered thunderstorm development initiating off the higher terrain this afternoon, and in advance of a cold front across central Montana. Forecast soundings shows large to very large surface temperature-dewpoint spreads (40-60 F) later this afternoon. A downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to severe-caliber wind gusts in consolidating outflows, as convection spreads eastward into this evening toward eastern Montana and possibly western North Dakota. Farther south over the Great Basin, model guidance appears to be trending towards greater storm coverage (numerous) and associated ability for storm outflow. The 12 UTC HREF in particular (and recent HRRR runs) shows a potential corridor of outflow surging convection from northeast NV into northwest and northern UT during the 23-04 UTC period. Some consideration for a Slight Risk was given but uncertainty precludes an upgrade at this time. ...Arizona... Lingering early day outflow/cloud cover via yesterday's relatively active convection should generally abate by afternoon. As the boundary layer diurnally warms and destabilizes, thunderstorms are again likely to initiate across the Mogollon Rim and adjacent mountains of southwest New Mexico this afternoon. Given the position and movement of the mid-level high, somewhat stronger (around 15 kt) northeasterly steering flow will remain focused across southeast into adjacent portions of central Arizona. Severe gusts will be possible later this afternoon into the mid-late evening as storms progress south-southwestward across the lower deserts of central and southern AZ. ...Carolinas/Mid-Atlantic States... Midday visible-satellite imagery shows and extensive cloud shield across much of NC into the southern half of VA. The 12 UTC GSO raob featuring poor lapse rates and meager buoyancy contrasted with the MHX raob (2000 J/kg MLCAPE) and a much more moisture-rich airmass. Thinner cloud cover near the coast will aid in widely scattered storms developing this afternoon largely removed from the southern fringe of large-scale troughing over the Mid-Atlantic states/Northeast. An isolated risk for locally severe gusts may develop for several hours this afternoon into the early evening. Farther north, breaks and thinning of cloud cover will promote stronger heating across northern VA into the northern half of the Chesapeake Bay vicinity than areas farther south. Widely scattered storms are forecast to develop per the latest 12 UTC HREF guidance within this corridor by mid-late afternoon. A belt of 40-50 kt southwesterly 500-mb flow may enhance storm vigor, and a few downdrafts may yield a risk for isolated 45-60 mph gusts capable of localized damage. ...Upper Texas Coast and Southwest Louisiana... Extensive showers and some thunderstorms are ongoing along the Texas coast early today. Influenced by a weak mid-level disturbance, some guidance suggests that a strengthening of low-level winds/shear may occur. However, mid-level winds will remain weak, while the aforementioned convection should considerably limit destabilization inland. These factors seem likely to minimize the potential for anything beyond a very weak/transient circulation. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Thu Jul 25 2024 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF CENTRAL AND NORTHEASTERN MONTANA...PORTIONS OF NORTHEASTERN NEVADA AND NORTHWESTERN UTAH... ...SUMMARY... Scattered severe thunderstorms capable of 60-75 mph gusts are forecast across portions of central/northeast Montana and northeastern Nevada/northwestern Utah late this afternoon into the evening. ...20z Update... A Slight Risk was introduced across northeastern Nevada and northwestern Utah, where scattered to numerous thunderstorms posing a risk of severe gusts should develop by the afternoon. Recent runs of the HRRR, as well as guidance from the 12Z HREF, continue to indicate the possibility of convection consolidating along outflow and surging northeast into northwestern Utah through the evening. Forecast sounding profiles support risk for severe gusts, with steep low to mid-level lapse rates and characteristic inverted-v indicative of large dew point spreads. This will support downward momentum transport of severe wind up to 60-70 mph, especially where outflow storms can consolidate along outflow. The Marginal Risk across Arizona was expanded westward into far southwestern Arizona to encompass potential for a cluster of thunderstorms to push westward by late evening. Thunderstorm activity is expected to continue across the high country before a gradual shift into the low deserts by the evening. Some consideration was given to a Slight Risk in this area but uncertainty remains in storm coverage along the Mogollon Rim and whether strong outflow will develop and move southwestward into the low terrain this evening. Otherwise, the eastern US Marginal Risk areas remain unchanged. Storms capable of locally damaging winds will continue to be possible through the afternoon and evening. ..Thornton/Smith.. 07/25/2024 .PREV DISCUSSION... /ISSUED 1131 AM CDT Thu Jul 25 2024/ ...Montana/Northern Rockies to Great Basin... Water-vapor imagery this morning shows an upper-level trough moving east from British Columbia toward Alberta/Saskatchewan, with strengthening cyclonic westerlies overspreading the northern Rockies/Montana. Model guidance continues to indicate scattered thunderstorm development initiating off the higher terrain this afternoon, and in advance of a cold front across central Montana. Forecast soundings shows large to very large surface temperature-dewpoint spreads (40-60 F) later this afternoon. A downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to severe-caliber wind gusts in consolidating outflows, as convection spreads eastward into this evening toward eastern Montana and possibly western North Dakota. Farther south over the Great Basin, model guidance appears to be trending towards greater storm coverage (numerous) and associated ability for storm outflow. The 12 UTC HREF in particular (and recent HRRR runs) shows a potential corridor of outflow surging convection from northeast NV into northwest and northern UT during the 23-04 UTC period. Some consideration for a Slight Risk was given but uncertainty precludes an upgrade at this time. ...Arizona... Lingering early day outflow/cloud cover via yesterday's relatively active convection should generally abate by afternoon. As the boundary layer diurnally warms and destabilizes, thunderstorms are again likely to initiate across the Mogollon Rim and adjacent mountains of southwest New Mexico this afternoon. Given the position and movement of the mid-level high, somewhat stronger (around 15 kt) northeasterly steering flow will remain focused across southeast into adjacent portions of central Arizona. Severe gusts will be possible later this afternoon into the mid-late evening as storms progress south-southwestward across the lower deserts of central and southern AZ. ...Carolinas/Mid-Atlantic States... Midday visible-satellite imagery shows and extensive cloud shield across much of NC into the southern half of VA. The 12 UTC GSO raob featuring poor lapse rates and meager buoyancy contrasted with the MHX raob (2000 J/kg MLCAPE) and a much more moisture-rich airmass. Thinner cloud cover near the coast will aid in widely scattered storms developing this afternoon largely removed from the southern fringe of large-scale troughing over the Mid-Atlantic states/Northeast. An isolated risk for locally severe gusts may develop for several hours this afternoon into the early evening. Farther north, breaks and thinning of cloud cover will promote stronger heating across northern VA into the northern half of the Chesapeake Bay vicinity than areas farther south. Widely scattered storms are forecast to develop per the latest 12 UTC HREF guidance within this corridor by mid-late afternoon. A belt of 40-50 kt southwesterly 500-mb flow may enhance storm vigor, and a few downdrafts may yield a risk for isolated 45-60 mph gusts capable of localized damage. ...Upper Texas Coast and Southwest Louisiana... Extensive showers and some thunderstorms are ongoing along the Texas coast early today. Influenced by a weak mid-level disturbance, some guidance suggests that a strengthening of low-level winds/shear may occur. However, mid-level winds will remain weak, while the aforementioned convection should considerably limit destabilization inland. These factors seem likely to minimize the potential for anything beyond a very weak/transient circulation. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Thu Jul 25 2024 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF CENTRAL AND NORTHEASTERN MONTANA...PORTIONS OF NORTHEASTERN NEVADA AND NORTHWESTERN UTAH... ...SUMMARY... Scattered severe thunderstorms capable of 60-75 mph gusts are forecast across portions of central/northeast Montana and northeastern Nevada/northwestern Utah late this afternoon into the evening. ...20z Update... A Slight Risk was introduced across northeastern Nevada and northwestern Utah, where scattered to numerous thunderstorms posing a risk of severe gusts should develop by the afternoon. Recent runs of the HRRR, as well as guidance from the 12Z HREF, continue to indicate the possibility of convection consolidating along outflow and surging northeast into northwestern Utah through the evening. Forecast sounding profiles support risk for severe gusts, with steep low to mid-level lapse rates and characteristic inverted-v indicative of large dew point spreads. This will support downward momentum transport of severe wind up to 60-70 mph, especially where outflow storms can consolidate along outflow. The Marginal Risk across Arizona was expanded westward into far southwestern Arizona to encompass potential for a cluster of thunderstorms to push westward by late evening. Thunderstorm activity is expected to continue across the high country before a gradual shift into the low deserts by the evening. Some consideration was given to a Slight Risk in this area but uncertainty remains in storm coverage along the Mogollon Rim and whether strong outflow will develop and move southwestward into the low terrain this evening. Otherwise, the eastern US Marginal Risk areas remain unchanged. Storms capable of locally damaging winds will continue to be possible through the afternoon and evening. ..Thornton/Smith.. 07/25/2024 .PREV DISCUSSION... /ISSUED 1131 AM CDT Thu Jul 25 2024/ ...Montana/Northern Rockies to Great Basin... Water-vapor imagery this morning shows an upper-level trough moving east from British Columbia toward Alberta/Saskatchewan, with strengthening cyclonic westerlies overspreading the northern Rockies/Montana. Model guidance continues to indicate scattered thunderstorm development initiating off the higher terrain this afternoon, and in advance of a cold front across central Montana. Forecast soundings shows large to very large surface temperature-dewpoint spreads (40-60 F) later this afternoon. A downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to severe-caliber wind gusts in consolidating outflows, as convection spreads eastward into this evening toward eastern Montana and possibly western North Dakota. Farther south over the Great Basin, model guidance appears to be trending towards greater storm coverage (numerous) and associated ability for storm outflow. The 12 UTC HREF in particular (and recent HRRR runs) shows a potential corridor of outflow surging convection from northeast NV into northwest and northern UT during the 23-04 UTC period. Some consideration for a Slight Risk was given but uncertainty precludes an upgrade at this time. ...Arizona... Lingering early day outflow/cloud cover via yesterday's relatively active convection should generally abate by afternoon. As the boundary layer diurnally warms and destabilizes, thunderstorms are again likely to initiate across the Mogollon Rim and adjacent mountains of southwest New Mexico this afternoon. Given the position and movement of the mid-level high, somewhat stronger (around 15 kt) northeasterly steering flow will remain focused across southeast into adjacent portions of central Arizona. Severe gusts will be possible later this afternoon into the mid-late evening as storms progress south-southwestward across the lower deserts of central and southern AZ. ...Carolinas/Mid-Atlantic States... Midday visible-satellite imagery shows and extensive cloud shield across much of NC into the southern half of VA. The 12 UTC GSO raob featuring poor lapse rates and meager buoyancy contrasted with the MHX raob (2000 J/kg MLCAPE) and a much more moisture-rich airmass. Thinner cloud cover near the coast will aid in widely scattered storms developing this afternoon largely removed from the southern fringe of large-scale troughing over the Mid-Atlantic states/Northeast. An isolated risk for locally severe gusts may develop for several hours this afternoon into the early evening. Farther north, breaks and thinning of cloud cover will promote stronger heating across northern VA into the northern half of the Chesapeake Bay vicinity than areas farther south. Widely scattered storms are forecast to develop per the latest 12 UTC HREF guidance within this corridor by mid-late afternoon. A belt of 40-50 kt southwesterly 500-mb flow may enhance storm vigor, and a few downdrafts may yield a risk for isolated 45-60 mph gusts capable of localized damage. ...Upper Texas Coast and Southwest Louisiana... Extensive showers and some thunderstorms are ongoing along the Texas coast early today. Influenced by a weak mid-level disturbance, some guidance suggests that a strengthening of low-level winds/shear may occur. However, mid-level winds will remain weak, while the aforementioned convection should considerably limit destabilization inland. These factors seem likely to minimize the potential for anything beyond a very weak/transient circulation. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Thu Jul 25 2024 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF CENTRAL AND NORTHEASTERN MONTANA...PORTIONS OF NORTHEASTERN NEVADA AND NORTHWESTERN UTAH... ...SUMMARY... Scattered severe thunderstorms capable of 60-75 mph gusts are forecast across portions of central/northeast Montana and northeastern Nevada/northwestern Utah late this afternoon into the evening. ...20z Update... A Slight Risk was introduced across northeastern Nevada and northwestern Utah, where scattered to numerous thunderstorms posing a risk of severe gusts should develop by the afternoon. Recent runs of the HRRR, as well as guidance from the 12Z HREF, continue to indicate the possibility of convection consolidating along outflow and surging northeast into northwestern Utah through the evening. Forecast sounding profiles support risk for severe gusts, with steep low to mid-level lapse rates and characteristic inverted-v indicative of large dew point spreads. This will support downward momentum transport of severe wind up to 60-70 mph, especially where outflow storms can consolidate along outflow. The Marginal Risk across Arizona was expanded westward into far southwestern Arizona to encompass potential for a cluster of thunderstorms to push westward by late evening. Thunderstorm activity is expected to continue across the high country before a gradual shift into the low deserts by the evening. Some consideration was given to a Slight Risk in this area but uncertainty remains in storm coverage along the Mogollon Rim and whether strong outflow will develop and move southwestward into the low terrain this evening. Otherwise, the eastern US Marginal Risk areas remain unchanged. Storms capable of locally damaging winds will continue to be possible through the afternoon and evening. ..Thornton/Smith.. 07/25/2024 .PREV DISCUSSION... /ISSUED 1131 AM CDT Thu Jul 25 2024/ ...Montana/Northern Rockies to Great Basin... Water-vapor imagery this morning shows an upper-level trough moving east from British Columbia toward Alberta/Saskatchewan, with strengthening cyclonic westerlies overspreading the northern Rockies/Montana. Model guidance continues to indicate scattered thunderstorm development initiating off the higher terrain this afternoon, and in advance of a cold front across central Montana. Forecast soundings shows large to very large surface temperature-dewpoint spreads (40-60 F) later this afternoon. A downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to severe-caliber wind gusts in consolidating outflows, as convection spreads eastward into this evening toward eastern Montana and possibly western North Dakota. Farther south over the Great Basin, model guidance appears to be trending towards greater storm coverage (numerous) and associated ability for storm outflow. The 12 UTC HREF in particular (and recent HRRR runs) shows a potential corridor of outflow surging convection from northeast NV into northwest and northern UT during the 23-04 UTC period. Some consideration for a Slight Risk was given but uncertainty precludes an upgrade at this time. ...Arizona... Lingering early day outflow/cloud cover via yesterday's relatively active convection should generally abate by afternoon. As the boundary layer diurnally warms and destabilizes, thunderstorms are again likely to initiate across the Mogollon Rim and adjacent mountains of southwest New Mexico this afternoon. Given the position and movement of the mid-level high, somewhat stronger (around 15 kt) northeasterly steering flow will remain focused across southeast into adjacent portions of central Arizona. Severe gusts will be possible later this afternoon into the mid-late evening as storms progress south-southwestward across the lower deserts of central and southern AZ. ...Carolinas/Mid-Atlantic States... Midday visible-satellite imagery shows and extensive cloud shield across much of NC into the southern half of VA. The 12 UTC GSO raob featuring poor lapse rates and meager buoyancy contrasted with the MHX raob (2000 J/kg MLCAPE) and a much more moisture-rich airmass. Thinner cloud cover near the coast will aid in widely scattered storms developing this afternoon largely removed from the southern fringe of large-scale troughing over the Mid-Atlantic states/Northeast. An isolated risk for locally severe gusts may develop for several hours this afternoon into the early evening. Farther north, breaks and thinning of cloud cover will promote stronger heating across northern VA into the northern half of the Chesapeake Bay vicinity than areas farther south. Widely scattered storms are forecast to develop per the latest 12 UTC HREF guidance within this corridor by mid-late afternoon. A belt of 40-50 kt southwesterly 500-mb flow may enhance storm vigor, and a few downdrafts may yield a risk for isolated 45-60 mph gusts capable of localized damage. ...Upper Texas Coast and Southwest Louisiana... Extensive showers and some thunderstorms are ongoing along the Texas coast early today. Influenced by a weak mid-level disturbance, some guidance suggests that a strengthening of low-level winds/shear may occur. However, mid-level winds will remain weak, while the aforementioned convection should considerably limit destabilization inland. These factors seem likely to minimize the potential for anything beyond a very weak/transient circulation. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Thu Jul 25 2024 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF CENTRAL AND NORTHEASTERN MONTANA...PORTIONS OF NORTHEASTERN NEVADA AND NORTHWESTERN UTAH... ...SUMMARY... Scattered severe thunderstorms capable of 60-75 mph gusts are forecast across portions of central/northeast Montana and northeastern Nevada/northwestern Utah late this afternoon into the evening. ...20z Update... A Slight Risk was introduced across northeastern Nevada and northwestern Utah, where scattered to numerous thunderstorms posing a risk of severe gusts should develop by the afternoon. Recent runs of the HRRR, as well as guidance from the 12Z HREF, continue to indicate the possibility of convection consolidating along outflow and surging northeast into northwestern Utah through the evening. Forecast sounding profiles support risk for severe gusts, with steep low to mid-level lapse rates and characteristic inverted-v indicative of large dew point spreads. This will support downward momentum transport of severe wind up to 60-70 mph, especially where outflow storms can consolidate along outflow. The Marginal Risk across Arizona was expanded westward into far southwestern Arizona to encompass potential for a cluster of thunderstorms to push westward by late evening. Thunderstorm activity is expected to continue across the high country before a gradual shift into the low deserts by the evening. Some consideration was given to a Slight Risk in this area but uncertainty remains in storm coverage along the Mogollon Rim and whether strong outflow will develop and move southwestward into the low terrain this evening. Otherwise, the eastern US Marginal Risk areas remain unchanged. Storms capable of locally damaging winds will continue to be possible through the afternoon and evening. ..Thornton/Smith.. 07/25/2024 .PREV DISCUSSION... /ISSUED 1131 AM CDT Thu Jul 25 2024/ ...Montana/Northern Rockies to Great Basin... Water-vapor imagery this morning shows an upper-level trough moving east from British Columbia toward Alberta/Saskatchewan, with strengthening cyclonic westerlies overspreading the northern Rockies/Montana. Model guidance continues to indicate scattered thunderstorm development initiating off the higher terrain this afternoon, and in advance of a cold front across central Montana. Forecast soundings shows large to very large surface temperature-dewpoint spreads (40-60 F) later this afternoon. A downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to severe-caliber wind gusts in consolidating outflows, as convection spreads eastward into this evening toward eastern Montana and possibly western North Dakota. Farther south over the Great Basin, model guidance appears to be trending towards greater storm coverage (numerous) and associated ability for storm outflow. The 12 UTC HREF in particular (and recent HRRR runs) shows a potential corridor of outflow surging convection from northeast NV into northwest and northern UT during the 23-04 UTC period. Some consideration for a Slight Risk was given but uncertainty precludes an upgrade at this time. ...Arizona... Lingering early day outflow/cloud cover via yesterday's relatively active convection should generally abate by afternoon. As the boundary layer diurnally warms and destabilizes, thunderstorms are again likely to initiate across the Mogollon Rim and adjacent mountains of southwest New Mexico this afternoon. Given the position and movement of the mid-level high, somewhat stronger (around 15 kt) northeasterly steering flow will remain focused across southeast into adjacent portions of central Arizona. Severe gusts will be possible later this afternoon into the mid-late evening as storms progress south-southwestward across the lower deserts of central and southern AZ. ...Carolinas/Mid-Atlantic States... Midday visible-satellite imagery shows and extensive cloud shield across much of NC into the southern half of VA. The 12 UTC GSO raob featuring poor lapse rates and meager buoyancy contrasted with the MHX raob (2000 J/kg MLCAPE) and a much more moisture-rich airmass. Thinner cloud cover near the coast will aid in widely scattered storms developing this afternoon largely removed from the southern fringe of large-scale troughing over the Mid-Atlantic states/Northeast. An isolated risk for locally severe gusts may develop for several hours this afternoon into the early evening. Farther north, breaks and thinning of cloud cover will promote stronger heating across northern VA into the northern half of the Chesapeake Bay vicinity than areas farther south. Widely scattered storms are forecast to develop per the latest 12 UTC HREF guidance within this corridor by mid-late afternoon. A belt of 40-50 kt southwesterly 500-mb flow may enhance storm vigor, and a few downdrafts may yield a risk for isolated 45-60 mph gusts capable of localized damage. ...Upper Texas Coast and Southwest Louisiana... Extensive showers and some thunderstorms are ongoing along the Texas coast early today. Influenced by a weak mid-level disturbance, some guidance suggests that a strengthening of low-level winds/shear may occur. However, mid-level winds will remain weak, while the aforementioned convection should considerably limit destabilization inland. These factors seem likely to minimize the potential for anything beyond a very weak/transient circulation. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Thu Jul 25 2024 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF CENTRAL AND NORTHEASTERN MONTANA...PORTIONS OF NORTHEASTERN NEVADA AND NORTHWESTERN UTAH... ...SUMMARY... Scattered severe thunderstorms capable of 60-75 mph gusts are forecast across portions of central/northeast Montana and northeastern Nevada/northwestern Utah late this afternoon into the evening. ...20z Update... A Slight Risk was introduced across northeastern Nevada and northwestern Utah, where scattered to numerous thunderstorms posing a risk of severe gusts should develop by the afternoon. Recent runs of the HRRR, as well as guidance from the 12Z HREF, continue to indicate the possibility of convection consolidating along outflow and surging northeast into northwestern Utah through the evening. Forecast sounding profiles support risk for severe gusts, with steep low to mid-level lapse rates and characteristic inverted-v indicative of large dew point spreads. This will support downward momentum transport of severe wind up to 60-70 mph, especially where outflow storms can consolidate along outflow. The Marginal Risk across Arizona was expanded westward into far southwestern Arizona to encompass potential for a cluster of thunderstorms to push westward by late evening. Thunderstorm activity is expected to continue across the high country before a gradual shift into the low deserts by the evening. Some consideration was given to a Slight Risk in this area but uncertainty remains in storm coverage along the Mogollon Rim and whether strong outflow will develop and move southwestward into the low terrain this evening. Otherwise, the eastern US Marginal Risk areas remain unchanged. Storms capable of locally damaging winds will continue to be possible through the afternoon and evening. ..Thornton/Smith.. 07/25/2024 .PREV DISCUSSION... /ISSUED 1131 AM CDT Thu Jul 25 2024/ ...Montana/Northern Rockies to Great Basin... Water-vapor imagery this morning shows an upper-level trough moving east from British Columbia toward Alberta/Saskatchewan, with strengthening cyclonic westerlies overspreading the northern Rockies/Montana. Model guidance continues to indicate scattered thunderstorm development initiating off the higher terrain this afternoon, and in advance of a cold front across central Montana. Forecast soundings shows large to very large surface temperature-dewpoint spreads (40-60 F) later this afternoon. A downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to severe-caliber wind gusts in consolidating outflows, as convection spreads eastward into this evening toward eastern Montana and possibly western North Dakota. Farther south over the Great Basin, model guidance appears to be trending towards greater storm coverage (numerous) and associated ability for storm outflow. The 12 UTC HREF in particular (and recent HRRR runs) shows a potential corridor of outflow surging convection from northeast NV into northwest and northern UT during the 23-04 UTC period. Some consideration for a Slight Risk was given but uncertainty precludes an upgrade at this time. ...Arizona... Lingering early day outflow/cloud cover via yesterday's relatively active convection should generally abate by afternoon. As the boundary layer diurnally warms and destabilizes, thunderstorms are again likely to initiate across the Mogollon Rim and adjacent mountains of southwest New Mexico this afternoon. Given the position and movement of the mid-level high, somewhat stronger (around 15 kt) northeasterly steering flow will remain focused across southeast into adjacent portions of central Arizona. Severe gusts will be possible later this afternoon into the mid-late evening as storms progress south-southwestward across the lower deserts of central and southern AZ. ...Carolinas/Mid-Atlantic States... Midday visible-satellite imagery shows and extensive cloud shield across much of NC into the southern half of VA. The 12 UTC GSO raob featuring poor lapse rates and meager buoyancy contrasted with the MHX raob (2000 J/kg MLCAPE) and a much more moisture-rich airmass. Thinner cloud cover near the coast will aid in widely scattered storms developing this afternoon largely removed from the southern fringe of large-scale troughing over the Mid-Atlantic states/Northeast. An isolated risk for locally severe gusts may develop for several hours this afternoon into the early evening. Farther north, breaks and thinning of cloud cover will promote stronger heating across northern VA into the northern half of the Chesapeake Bay vicinity than areas farther south. Widely scattered storms are forecast to develop per the latest 12 UTC HREF guidance within this corridor by mid-late afternoon. A belt of 40-50 kt southwesterly 500-mb flow may enhance storm vigor, and a few downdrafts may yield a risk for isolated 45-60 mph gusts capable of localized damage. ...Upper Texas Coast and Southwest Louisiana... Extensive showers and some thunderstorms are ongoing along the Texas coast early today. Influenced by a weak mid-level disturbance, some guidance suggests that a strengthening of low-level winds/shear may occur. However, mid-level winds will remain weak, while the aforementioned convection should considerably limit destabilization inland. These factors seem likely to minimize the potential for anything beyond a very weak/transient circulation. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Thu Jul 25 2024 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF CENTRAL AND NORTHEASTERN MONTANA...PORTIONS OF NORTHEASTERN NEVADA AND NORTHWESTERN UTAH... ...SUMMARY... Scattered severe thunderstorms capable of 60-75 mph gusts are forecast across portions of central/northeast Montana and northeastern Nevada/northwestern Utah late this afternoon into the evening. ...20z Update... A Slight Risk was introduced across northeastern Nevada and northwestern Utah, where scattered to numerous thunderstorms posing a risk of severe gusts should develop by the afternoon. Recent runs of the HRRR, as well as guidance from the 12Z HREF, continue to indicate the possibility of convection consolidating along outflow and surging northeast into northwestern Utah through the evening. Forecast sounding profiles support risk for severe gusts, with steep low to mid-level lapse rates and characteristic inverted-v indicative of large dew point spreads. This will support downward momentum transport of severe wind up to 60-70 mph, especially where outflow storms can consolidate along outflow. The Marginal Risk across Arizona was expanded westward into far southwestern Arizona to encompass potential for a cluster of thunderstorms to push westward by late evening. Thunderstorm activity is expected to continue across the high country before a gradual shift into the low deserts by the evening. Some consideration was given to a Slight Risk in this area but uncertainty remains in storm coverage along the Mogollon Rim and whether strong outflow will develop and move southwestward into the low terrain this evening. Otherwise, the eastern US Marginal Risk areas remain unchanged. Storms capable of locally damaging winds will continue to be possible through the afternoon and evening. ..Thornton/Smith.. 07/25/2024 .PREV DISCUSSION... /ISSUED 1131 AM CDT Thu Jul 25 2024/ ...Montana/Northern Rockies to Great Basin... Water-vapor imagery this morning shows an upper-level trough moving east from British Columbia toward Alberta/Saskatchewan, with strengthening cyclonic westerlies overspreading the northern Rockies/Montana. Model guidance continues to indicate scattered thunderstorm development initiating off the higher terrain this afternoon, and in advance of a cold front across central Montana. Forecast soundings shows large to very large surface temperature-dewpoint spreads (40-60 F) later this afternoon. A downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to severe-caliber wind gusts in consolidating outflows, as convection spreads eastward into this evening toward eastern Montana and possibly western North Dakota. Farther south over the Great Basin, model guidance appears to be trending towards greater storm coverage (numerous) and associated ability for storm outflow. The 12 UTC HREF in particular (and recent HRRR runs) shows a potential corridor of outflow surging convection from northeast NV into northwest and northern UT during the 23-04 UTC period. Some consideration for a Slight Risk was given but uncertainty precludes an upgrade at this time. ...Arizona... Lingering early day outflow/cloud cover via yesterday's relatively active convection should generally abate by afternoon. As the boundary layer diurnally warms and destabilizes, thunderstorms are again likely to initiate across the Mogollon Rim and adjacent mountains of southwest New Mexico this afternoon. Given the position and movement of the mid-level high, somewhat stronger (around 15 kt) northeasterly steering flow will remain focused across southeast into adjacent portions of central Arizona. Severe gusts will be possible later this afternoon into the mid-late evening as storms progress south-southwestward across the lower deserts of central and southern AZ. ...Carolinas/Mid-Atlantic States... Midday visible-satellite imagery shows and extensive cloud shield across much of NC into the southern half of VA. The 12 UTC GSO raob featuring poor lapse rates and meager buoyancy contrasted with the MHX raob (2000 J/kg MLCAPE) and a much more moisture-rich airmass. Thinner cloud cover near the coast will aid in widely scattered storms developing this afternoon largely removed from the southern fringe of large-scale troughing over the Mid-Atlantic states/Northeast. An isolated risk for locally severe gusts may develop for several hours this afternoon into the early evening. Farther north, breaks and thinning of cloud cover will promote stronger heating across northern VA into the northern half of the Chesapeake Bay vicinity than areas farther south. Widely scattered storms are forecast to develop per the latest 12 UTC HREF guidance within this corridor by mid-late afternoon. A belt of 40-50 kt southwesterly 500-mb flow may enhance storm vigor, and a few downdrafts may yield a risk for isolated 45-60 mph gusts capable of localized damage. ...Upper Texas Coast and Southwest Louisiana... Extensive showers and some thunderstorms are ongoing along the Texas coast early today. Influenced by a weak mid-level disturbance, some guidance suggests that a strengthening of low-level winds/shear may occur. However, mid-level winds will remain weak, while the aforementioned convection should considerably limit destabilization inland. These factors seem likely to minimize the potential for anything beyond a very weak/transient circulation. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Thu Jul 25 2024 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF CENTRAL AND NORTHEASTERN MONTANA...PORTIONS OF NORTHEASTERN NEVADA AND NORTHWESTERN UTAH... ...SUMMARY... Scattered severe thunderstorms capable of 60-75 mph gusts are forecast across portions of central/northeast Montana and northeastern Nevada/northwestern Utah late this afternoon into the evening. ...20z Update... A Slight Risk was introduced across northeastern Nevada and northwestern Utah, where scattered to numerous thunderstorms posing a risk of severe gusts should develop by the afternoon. Recent runs of the HRRR, as well as guidance from the 12Z HREF, continue to indicate the possibility of convection consolidating along outflow and surging northeast into northwestern Utah through the evening. Forecast sounding profiles support risk for severe gusts, with steep low to mid-level lapse rates and characteristic inverted-v indicative of large dew point spreads. This will support downward momentum transport of severe wind up to 60-70 mph, especially where outflow storms can consolidate along outflow. The Marginal Risk across Arizona was expanded westward into far southwestern Arizona to encompass potential for a cluster of thunderstorms to push westward by late evening. Thunderstorm activity is expected to continue across the high country before a gradual shift into the low deserts by the evening. Some consideration was given to a Slight Risk in this area but uncertainty remains in storm coverage along the Mogollon Rim and whether strong outflow will develop and move southwestward into the low terrain this evening. Otherwise, the eastern US Marginal Risk areas remain unchanged. Storms capable of locally damaging winds will continue to be possible through the afternoon and evening. ..Thornton/Smith.. 07/25/2024 .PREV DISCUSSION... /ISSUED 1131 AM CDT Thu Jul 25 2024/ ...Montana/Northern Rockies to Great Basin... Water-vapor imagery this morning shows an upper-level trough moving east from British Columbia toward Alberta/Saskatchewan, with strengthening cyclonic westerlies overspreading the northern Rockies/Montana. Model guidance continues to indicate scattered thunderstorm development initiating off the higher terrain this afternoon, and in advance of a cold front across central Montana. Forecast soundings shows large to very large surface temperature-dewpoint spreads (40-60 F) later this afternoon. A downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to severe-caliber wind gusts in consolidating outflows, as convection spreads eastward into this evening toward eastern Montana and possibly western North Dakota. Farther south over the Great Basin, model guidance appears to be trending towards greater storm coverage (numerous) and associated ability for storm outflow. The 12 UTC HREF in particular (and recent HRRR runs) shows a potential corridor of outflow surging convection from northeast NV into northwest and northern UT during the 23-04 UTC period. Some consideration for a Slight Risk was given but uncertainty precludes an upgrade at this time. ...Arizona... Lingering early day outflow/cloud cover via yesterday's relatively active convection should generally abate by afternoon. As the boundary layer diurnally warms and destabilizes, thunderstorms are again likely to initiate across the Mogollon Rim and adjacent mountains of southwest New Mexico this afternoon. Given the position and movement of the mid-level high, somewhat stronger (around 15 kt) northeasterly steering flow will remain focused across southeast into adjacent portions of central Arizona. Severe gusts will be possible later this afternoon into the mid-late evening as storms progress south-southwestward across the lower deserts of central and southern AZ. ...Carolinas/Mid-Atlantic States... Midday visible-satellite imagery shows and extensive cloud shield across much of NC into the southern half of VA. The 12 UTC GSO raob featuring poor lapse rates and meager buoyancy contrasted with the MHX raob (2000 J/kg MLCAPE) and a much more moisture-rich airmass. Thinner cloud cover near the coast will aid in widely scattered storms developing this afternoon largely removed from the southern fringe of large-scale troughing over the Mid-Atlantic states/Northeast. An isolated risk for locally severe gusts may develop for several hours this afternoon into the early evening. Farther north, breaks and thinning of cloud cover will promote stronger heating across northern VA into the northern half of the Chesapeake Bay vicinity than areas farther south. Widely scattered storms are forecast to develop per the latest 12 UTC HREF guidance within this corridor by mid-late afternoon. A belt of 40-50 kt southwesterly 500-mb flow may enhance storm vigor, and a few downdrafts may yield a risk for isolated 45-60 mph gusts capable of localized damage. ...Upper Texas Coast and Southwest Louisiana... Extensive showers and some thunderstorms are ongoing along the Texas coast early today. Influenced by a weak mid-level disturbance, some guidance suggests that a strengthening of low-level winds/shear may occur. However, mid-level winds will remain weak, while the aforementioned convection should considerably limit destabilization inland. These factors seem likely to minimize the potential for anything beyond a very weak/transient circulation. Read more