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MD 1804 CONCERNING SEVERE THUNDERSTORM WATCH 545... FOR NORTHEAST MONTANA INTO NORTHWEST NORTH DAKOTA
Mesoscale Discussion 1804 NWS Storm Prediction Center Norman OK 1128 PM CDT Sat Jul 26 2025 Areas affected...Northeast Montana into northwest North Dakota Concerning...Severe Thunderstorm Watch 545... Valid 270428Z - 270600Z The severe weather threat for Severe Thunderstorm Watch 545 continues. SUMMARY...An MCS with a history of producing severe winds is expected to spread into northwest/western North Dakota through the early morning hours. Downstream watch issuance is being considered, though confidence in MCS intensity is waning to some degree. DISCUSSION...The MCS moving across northeast MT has a history of producing 50-56 knot winds within the past few hours. However, more recent radar imagery from KGGW shows the MCS has become outflow dominant with a decrease in lightning activity noted as well. This casts some uncertainty onto how intense the MCS will be in the coming hours as it pushes into northwest ND where inhibition is slowly increasing with the onset of nocturnal cooling. Reflectivity composites and GOES IR imagery both show strong embedded updrafts within this line, and rich low-level moisture remains in place immediately downstream. Recent radar trends also show the deeper/stronger convective cores developing slightly southward towards the better buoyancy/moisture, hinting that the MCS may propagate along the buoyancy axis in place across west-central ND. As such, there remains some potential for a severe wind threat with this MCS as it moves east over the coming hours, though the magnitude/coverage of severe winds appears uncertain at this time. Regardless, watch issuance is being considered for northwest/western ND. ..Moore.. 07/27/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BIS...BYZ...GGW... LAT...LON 47100676 47300643 47720640 48080642 48340653 48670643 48760300 48710268 48550246 47640240 47060256 46820285 46690328 46660400 46840670 46960685 47100676 MOST PROBABLE PEAK WIND GUST...55-70 MPH Read more

MD 1803 CONCERNING SEVERE THUNDERSTORM WATCH 546... FOR PORTIONS OF THE EASTERN DAKOTAS
Mesoscale Discussion 1803 NWS Storm Prediction Center Norman OK 1059 PM CDT Sat Jul 26 2025 Areas affected...Portions of the eastern Dakotas Concerning...Severe Thunderstorm Watch 546... Valid 270359Z - 270600Z The severe weather threat for Severe Thunderstorm Watch 546 continues. SUMMARY...Strong to severe thunderstorms will continue to spread north and east into eastern North Dakota and northeast South Dakota through the overnight hours. Downstream watch issuance and/or expansions are expected in the next couple of hours. DISCUSSION...Regional radar trends show initially discrete cells from southern ND and central SD transitioning into semi-organize convective clusters/lines. Recent severe wind reports have been noted with one such cluster moving across central SD within the past hour. This activity is slowly moving into a more capped environment with diminishing deep-layer wind shear; however, cold-pool propagation into an otherwise buoyant environment should help maintain this activity into the early morning hours with an attendant threat for severe winds. Further north, convection building across southern ND is expected to continue spreading north/northeast within a zone of weak isentropic ascent between 925-850 mb. This zone is co-located with a regional buoyancy maximum across east/southeast ND and where stronger mid-level flow is supporting effective shear values of around 35-40 knots. As such, a mix of strong to severe clusters and embedded supercells is likely heading into the early morning hours. Downstream watch issuance is expected given the potential for severe gusts and large hail. ..Moore.. 07/27/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGF...FSD...ABR...BIS... LAT...LON 44609957 45149914 45549901 45899910 46159919 46309958 46340007 46300042 46250081 46290102 46430119 46670118 47310072 47630023 47889937 47899874 47809815 47689777 47459728 47089685 46809666 46429656 46069653 45169660 44899670 44609688 44419722 44249769 44169806 44169865 44229909 44409941 44529954 44609957 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN Read more

WW 0545 Status Updates
STATUS REPORT ON WW 545 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 WSW GDV TO 55 N GGW. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1804. ..GRAMS..07/27/25 ATTN...WFO...TFX...GGW...BYZ... STATUS REPORT FOR WS 545 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC019-021-055-079-083-085-091-109-270640- MT . MONTANA COUNTIES INCLUDED ARE DANIELS DAWSON MCCONE PRAIRIE RICHLAND ROOSEVELT SHERIDAN WIBAUX THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

835
ABPZ20 KNHC 270524
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Sat Jul 26 2025

For the eastern and central North Pacific east of 180 longitude:

Eastern portion of the Central Pacific (CP90):
Showers and thunderstorms associated with an area of low pressure
about 900 miles southeast of the Hawaiian Islands have become better
organized since earlier today. Additional development of this system
is expected and a tropical depression is likely to form later
tonight or Sunday as it moves generally westward around 10 mph, well
to the south of the Hawaiian Islands.
* Formation chance through 48 hours...high...80 percent.
* Formation chance through 7 days...high...80 percent.

Western East Pacific:
A trough of low pressure about 1700 miles east-southeast of the
Hawaiian Islands is producing a large area of disorganized showers
and thunderstorms. Some gradual development of this system is
possible during the next few days at it moves generally westward
around 10 mph.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...low...30 percent.

South of Southwestern Mexico:
An area of low pressure is forecast to form well offshore of the
southwestern coast of Mexico early next week. Thereafter,
environmental conditions appear conducive for gradual development,
and a tropical depression could form during the middle to latter
part of next week as the system moves west-northwestward or
northwestward at 10 to 15 mph.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...40 percent.

$$
Forecaster Jelsema

WW 0547 Status Updates
STATUS FOR WATCH 0547 HAS NOT BEEN ISSUED YET Read more

WW 0547 Status Updates
STATUS FOR WATCH 0547 HAS NOT BEEN ISSUED YET Read more

WW 0546 Status Updates
STATUS REPORT ON WW 546 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 W PHP TO 30 WNW 4BQ. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1803 ..MOORE..07/27/25 ATTN...WFO...BYZ...BIS...UNR...ABR... STATUS REPORT FOR WS 546 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC011-025-270540- MT . MONTANA COUNTIES INCLUDED ARE CARTER FALLON NDC001-011-015-021-029-037-041-043-045-047-051-059-085-087-093- 270540- ND . NORTH DAKOTA COUNTIES INCLUDED ARE ADAMS BOWMAN BURLEIGH DICKEY EMMONS GRANT HETTINGER KIDDER LAMOURE LOGAN MCINTOSH MORTON SIOUX SLOPE STUTSMAN SDC019-021-031-041-045-049-063-075-089-093-105-107-115-117-119- 129-137-270540- Read more

WW 0546 Status Updates
STATUS REPORT ON WW 546 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 W PHP TO 30 WNW 4BQ. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1803 ..MOORE..07/27/25 ATTN...WFO...BYZ...BIS...UNR...ABR... STATUS REPORT FOR WS 546 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC011-025-270540- MT . MONTANA COUNTIES INCLUDED ARE CARTER FALLON NDC001-011-015-021-029-037-041-043-045-047-051-059-085-087-093- 270540- ND . NORTH DAKOTA COUNTIES INCLUDED ARE ADAMS BOWMAN BURLEIGH DICKEY EMMONS GRANT HETTINGER KIDDER LAMOURE LOGAN MCINTOSH MORTON SIOUX SLOPE STUTSMAN SDC019-021-031-041-045-049-063-075-089-093-105-107-115-117-119- 129-137-270540- Read more

MD 1801 CONCERNING SEVERE THUNDERSTORM WATCH 546... FOR PORTIONS OF THE CENTRAL DAKOTAS AND FAR SOUTHEAST MONTANA
Mesoscale Discussion 1801 NWS Storm Prediction Center Norman OK 0930 PM CDT Sat Jul 26 2025 Areas affected...Portions of the central Dakotas and far southeast Montana Concerning...Severe Thunderstorm Watch 546... Valid 270230Z - 270430Z The severe weather threat for Severe Thunderstorm Watch 546 continues. SUMMARY...Several localized corridors of heightened severe weather potential are emerging across the central Dakotas and far southeast Montana. DISCUSSION...A complex convective situation continues to unfold across the Dakotas with several areas of localized concern beginning to emerge. Along the ND/SD border, explosive updraft development is noted in GOES imagery. This convection is developing within an extremely, and thus far untapped, air mass with MLCAPE estimates of around 4000 J/kg and mid-level lapse rates on the order of 9 C/km (per regional 00z RAOBs). This new convection will likely develop into one or more organized supercells given adequate deep-layer wind shear (around 30-40 knots per regional soundings) with an attendant threat for large to very large (1.5-2.75 inch) hail and severe gusts. RAP mesoanalysis estimates also characterize the environment with STP values between 3-5, and while these values are likely being driven by extreme buoyancy, some low-level veering is noted within the 0-2 km layer per the KABR VWP, suggesting at least some localized tornado threat. To the south, a cluster of supercells is beginning to grow upscale. KABR velocity imagery shows an uptick in low-level outflow as this transition occurs, suggesting severe winds may become the primary hazard over the next hour or two. Along the MT/SD border, several supercells are noted in regional radar imagery, and storm spacing appears sufficient to maintain the storm mode for the near-term (next hour or so). As such, the primary hazard should remain large hail, though additional updraft development is noted in GOES imagery across southeast MT, suggesting that upscale growth is still probable over the next few hours as this activity spreads northeast into the Dakotas. As this occurs, the potential for severe winds should increase. ..Moore.. 07/27/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ABR...BIS...UNR...BYZ... LAT...LON 44860421 45000465 45240493 45590495 45850481 46000447 46620097 46679973 46539917 46209887 45779869 45419870 44929878 44639925 44529998 44740381 44860421 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN Read more

MD 1802 CONCERNING SEVERE THUNDERSTORM WATCH 545... FOR NORTHEAST MONTANA
Mesoscale Discussion 1802 NWS Storm Prediction Center Norman OK 0942 PM CDT Sat Jul 26 2025 Areas affected...Northeast Montana Concerning...Severe Thunderstorm Watch 545... Valid 270242Z - 270415Z The severe weather threat for Severe Thunderstorm Watch 545 continues. SUMMARY...A localized corridor of significant (70-85 mph) winds may be emerging across northeast Montana for the next hour or so. DISCUSSION...KGGW velocity imagery shows a localized surge in a maturing MCS that is the result of a recent squall-line/supercell merger. This merger is likely the initiating mechanism for a somewhat prolonged (1-2 hour) surge of severe - to potentially significant - wind gusts downstream across northeast MT. Recent observations from the 00 UTC GGW sounding and the KGGW VWP show very steep mid-level lapse rates and favorable deep-layer wind shear for MCS maintenance, including very strong 0-3 km BWD values on the order of 40 knots. Consequently, given this environment and the recent convective trends, the potential for wind gusts as high as 70-85 mph appears to be increasing. ..Moore.. 07/27/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GGW... LAT...LON 47450749 47650755 47960763 48120761 48690577 48630534 48490507 48160488 47950490 47780497 47650506 47600533 47450749 MOST PROBABLE PEAK WIND GUST...65-80 MPH Read more

WW 0546 Status Updates
STATUS REPORT ON WW 546 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 W PHP TO 30 WNW 4BQ. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1801 ..MOORE..07/27/25 ATTN...WFO...BYZ...BIS...UNR...ABR... STATUS REPORT FOR WS 546 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC011-025-270440- MT . MONTANA COUNTIES INCLUDED ARE CARTER FALLON NDC001-011-015-021-029-037-041-043-045-047-051-059-085-087-093- 270440- ND . NORTH DAKOTA COUNTIES INCLUDED ARE ADAMS BOWMAN BURLEIGH DICKEY EMMONS GRANT HETTINGER KIDDER LAMOURE LOGAN MCINTOSH MORTON SIOUX SLOPE STUTSMAN SDC019-021-031-041-045-049-063-075-089-093-105-107-117-119-129- 137-270440- Read more

WW 0545 Status Updates
STATUS REPORT ON WW 545 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 60 NE BIL TO 80 ENE HVR. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1802 ..MOORE..07/27/25 ATTN...WFO...TFX...GGW...BYZ... STATUS REPORT FOR WS 545 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC019-021-033-055-071-079-083-085-091-105-109-270440- MT . MONTANA COUNTIES INCLUDED ARE DANIELS DAWSON GARFIELD MCCONE PHILLIPS PRAIRIE RICHLAND ROOSEVELT SHERIDAN VALLEY WIBAUX THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0545 Status Updates
STATUS REPORT ON WW 545 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 60 NE BIL TO 80 ENE HVR. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1802 ..MOORE..07/27/25 ATTN...WFO...TFX...GGW...BYZ... STATUS REPORT FOR WS 545 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC019-021-033-055-071-079-083-085-091-105-109-270440- MT . MONTANA COUNTIES INCLUDED ARE DANIELS DAWSON GARFIELD MCCONE PHILLIPS PRAIRIE RICHLAND ROOSEVELT SHERIDAN VALLEY WIBAUX THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

MD 1800 CONCERNING SEVERE THUNDERSTORM WATCH 545... FOR NORTHEAST MONTANA
Mesoscale Discussion 1800 NWS Storm Prediction Center Norman OK 0756 PM CDT Sat Jul 26 2025 Areas affected...Northeast Montana Concerning...Severe Thunderstorm Watch 545... Valid 270056Z - 270300Z The severe weather threat for Severe Thunderstorm Watch 545 continues. SUMMARY...A developing squall line will likely see intensification over the next 1-2 hours as it moves into a more buoyant air mass downstream across northeast Montana. DISCUSSION...Regional velocity imagery from KTFX and KBLX show cold pool consolidation underway across central MT as a squall line slowly organizes. Despite the anemic reflectivity presentation over the past 20 minutes, GOES 1-minute IR imagery shows multiple deep convective updrafts embedded within the line, and recent lighting data shows an uptick in lightning flashes with strong clustering around developing updrafts - indicative of an overall intensification trend. This trend should continue for the next few hours as the line continues to move east/northeast into an increasingly buoyant air mass (downstream MLCAPE is upwards of 1000-2000 J/kg over northeast MT). Additionally, easterly flow through the lowest 2 km should help maintain a balanced cold pool and promote squall line longevity. Consequently, the potential for severe winds should increase through the evening hours across northeast MT. Further downstream ahead of the line, a pair of supercells continue to slowly mature with MRMS data showing increasing probability of severe hail. These cells will continue to migrate east/southeast towards the regional MLCAPE axis, which should promote storm longevity and the potential for further intensification. Based on recent vertical ice data and the downstream environment, large hail, possibly between 1 to 2 inches, appears possible before these cells merge with the approaching squall line. ..Moore.. 07/27/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BYZ...GGW...TFX... LAT...LON 47110436 46360835 46430859 46680868 47170896 47530927 47650930 47790924 48890592 48880533 48740495 48540469 48270446 47740423 47390418 47110436 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

WW 0546 Status Updates
STATUS REPORT ON WW 546 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 60 W RAP TO 65 SSW 2WX TO 10 SW 4BQ. ..MOORE..07/27/25 ATTN...WFO...BYZ...BIS...UNR...ABR... STATUS REPORT FOR WS 546 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC011-025-270240- MT . MONTANA COUNTIES INCLUDED ARE CARTER FALLON NDC001-011-015-021-029-037-041-043-045-047-051-059-085-087-093- 270240- ND . NORTH DAKOTA COUNTIES INCLUDED ARE ADAMS BOWMAN BURLEIGH DICKEY EMMONS GRANT HETTINGER KIDDER LAMOURE LOGAN MCINTOSH MORTON SIOUX SLOPE STUTSMAN SDC019-021-031-041-045-049-063-075-081-089-093-105-107-117-119- 129-137-270240- SD Read more

WW 0546 Status Updates
STATUS REPORT ON WW 546 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 60 W RAP TO 65 SSW 2WX TO 10 SW 4BQ. ..MOORE..07/27/25 ATTN...WFO...BYZ...BIS...UNR...ABR... STATUS REPORT FOR WS 546 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC011-025-270240- MT . MONTANA COUNTIES INCLUDED ARE CARTER FALLON NDC001-011-015-021-029-037-041-043-045-047-051-059-085-087-093- 270240- ND . NORTH DAKOTA COUNTIES INCLUDED ARE ADAMS BOWMAN BURLEIGH DICKEY EMMONS GRANT HETTINGER KIDDER LAMOURE LOGAN MCINTOSH MORTON SIOUX SLOPE STUTSMAN SDC019-021-031-041-045-049-063-075-081-089-093-105-107-117-119- 129-137-270240- SD Read more

WW 0545 Status Updates
STATUS REPORT ON WW 545 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 NE BIL TO 45 N HVR. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1800 ..MOORE..07/27/25 ATTN...WFO...TFX...GGW...BYZ... STATUS REPORT FOR WS 545 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC005-019-021-033-055-069-071-079-083-085-091-105-109-270240- MT . MONTANA COUNTIES INCLUDED ARE BLAINE DANIELS DAWSON GARFIELD MCCONE PETROLEUM PHILLIPS PRAIRIE RICHLAND ROOSEVELT SHERIDAN VALLEY WIBAUX THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0545 Status Updates
STATUS REPORT ON WW 545 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 NE BIL TO 45 N HVR. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1800 ..MOORE..07/27/25 ATTN...WFO...TFX...GGW...BYZ... STATUS REPORT FOR WS 545 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC005-019-021-033-055-069-071-079-083-085-091-105-109-270240- MT . MONTANA COUNTIES INCLUDED ARE BLAINE DANIELS DAWSON GARFIELD MCCONE PETROLEUM PHILLIPS PRAIRIE RICHLAND ROOSEVELT SHERIDAN VALLEY WIBAUX THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

MD 1799 CONCERNING SEVERE THUNDERSTORM WATCH 544... FOR PORTIONS OF EXTREME NORTHEAST COLORADO INTO WESTERN NEBRASKA AND FAR SOUTH-CENTRAL SOUTH DAKOTA
Mesoscale Discussion 1799 NWS Storm Prediction Center Norman OK 0716 PM CDT Sat Jul 26 2025 Areas affected...portions of extreme northeast Colorado into western Nebraska and far south-central South Dakota Concerning...Severe Thunderstorm Watch 544... Valid 270016Z - 270145Z The severe weather threat for Severe Thunderstorm Watch 544 continues. SUMMARY...Severe gusts will remain a concern over the next several hours with an eastward-advancing MCS. DISCUSSION...An MCS is organizing over western NE, where several sub-severe gusts have been measured. Over the next several hours, this MCS cold-pool-driven MCS will propagate eastward amid 3000+ J/kg MLCAPE. Deep-layer shear is not overly strong, and MLCINH is beginning to increase across the central Plains. Nonetheless, the 25+ kt effective bulk shear vectors in place are roughly normal to the MCS leading line, so continued organization is not out of the question. Should the MCS continue to intensify, severe gusts may become more probable before the MCS becomes increasingly elevated with strengthening MLCINH. ..Squitieri.. 07/27/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...UNR...BOU... LAT...LON 40590244 42110214 43070154 43390090 43430033 43340011 42849993 41960009 41010032 40610057 40440130 40460184 40590244 MOST PROBABLE PEAK WIND GUST...65-80 MPH Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0802 PM CDT Sat Jul 26 2025 Valid 270100Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTH-CENTRAL U.S.... ...SUMMARY... Severe thunderstorms with damaging wind gusts and hail will be possible this evening into tonight across parts of the northern Plains from eastern Montana into the Dakotas and southward to Nebraska. Isolated damaging wind gusts will also be possible this evening from parts of the mid Mississippi Valley eastward into the Mid-Atlantic. ...Central and Northern Plains/Northern Rockies... At mid-levels, a ridge will remain located over the northern Plains this evening, as a shortwave trough approaches from the southwest. The shortwave is moving northeastward across the central and northern Rockies, which is evident on water vapor imagery. Ahead of this feature, large-scale ascent will overspread a moist airmass located across the central and northern Plains. Surface dewpoints within this airmass are mostly from the mid 60s to mid 70s F. This is contributing to a large pocket of strong instability across the Dakotas, where MLCAPE is estimated to be in the 3500 to 5500 J/kg range, according to RAP analysis data. Moderate instability extends southward into the central Plains. Along the western edge of the stronger instability, a broken line of thunderstorms is ongoing from central South Dakota southward into western Nebraska. Moderate deep-layer shear is analyzed by the RAP over much central and northern Plains. The stronger flow is a result of upper-level jets located over far southern Canada and central Nebraska. RAP forecast soundings from western Nebraska northward into the central Dakotas generally show 0-6 km shear in the 30 to 40 knot range, with directional shear located in the low to mid-levels. This will be favorable for supercell development this evening, mainly with cells that remain semi-discrete. Supercells will likely have an isolated large hail threat, mainly from central South Dakota into southern and eastern North Dakota, where the strongest instability is located. Hailstones greater than 2 inches in diameter will be possible. In addition, organized line segments with wind-damage potential are expected. Further west into parts of the northern High Plains, scattered thunderstorms are ongoing across central and northeast Montana. As the shortwave trough moves across the region this evening, convective coverage is expected to gradually increase. A severe threat will be possible along an near an axis of moderate instability, which the RAP currently shows from northwestern North Dakota into north-central Montana. Very steep low to mid-level lapse rates would be favorable for damaging wind gusts with the stronger storms. ....Mid Mississippi and Ohio Valleys/Central Appalachians/Mid-Atlantic... A mid-level trough is currently evident on water vapor imagery over the central and southern Great Lakes. Scattered thunderstorms are ongoing along the southern edge of this feature from the mid Mississippi Valley eastward into the central Appalachians. Along this east-to-west corridor, surface dewpoints are from the 70s into the lower 80s F. This is contributing to moderate instability, which is present over most of the region. The unstable environment should support a marginal wind-damage threat associated with the stronger multicells this evening. ..Broyles.. 07/27/2025 Read more