Mesoscale Discussion 1561
Issued: · Valid: –
Summary
Isolated to widely scattered thunderstorms may bring large hail and damaging wind gusts to portions of western South Dakota and central to northeastern North Dakota through this evening.
Product Text
000 ACUS11 KWNS 092058 SWOMCD SPC MCD 092058 NDZ000-SDZ000-092300- Mesoscale Discussion 1561 NWS Storm Prediction Center Norman OK 0358 PM CDT Thu Jul 09 2026 Areas affected...portions of western South Dakota into central/northeastern North Dakota Concerning...Severe potential...Watch possible Valid 092058Z - 092300Z Probability of Watch Issuance...40 percent SUMMARY...Isolated to widely scattered thunderstorms will bring a risk for large hail and damaging/severe wind gusts through this evening. DISCUSSION...Latest observations depict ongoing thunderstorms in close proximity to a convectively augmented shortwave trough noted over far southern Manitoba with developing, agitated cumulus also noted farther southwest over northwestern South Dakota. Aided by ascent ahead of this shortwave and weak convergence along a surface pre-frontal trough/weak wind shift, expectation is for ongoing thunderstorm activity to persist southeastward into North Dakota and for additional isolated to widely scattered thunderstorms to develop southwestward into western South Dakota. Moderate to strong buoyancy (up to 2500-3000 J/kg MLCAPE noted via latest mesoanalysis) and effective shear of 30-40 kts (as sampled by the 18z BIS observed sounding) will support supercells and a risk for large hail (including perhaps an isolated instance to around 2" in diameter) and damaging/severe wind gusts. Uncertainty remains regarding eventual thunderstorm and severe coverage, but a Severe Thunderstorm Watch may be needed for a portion of the discussion area to cover these threats should a corridor of greater severe potential become evident, such as across portions of central/eastern North Dakota where effective shear is modestly greater and where latest guidance suggests convective coverage may be greater. ..Chalmers/Thompson.. 07/09/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGF...ABR...BIS...UNR... LAT...LON 44300060 43880080 43300099 43150108 43080123 43050180 43070271 43210331 43410363 43760396 44230404 45070381 45750329 46980165 47980060 49029970 49199950 49209808 49199769 49049754 48479753 47879764 47419786 45759966 44300060 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN