Mesoscale Discussion 1553
NWS Storm Prediction Center Norman OK
0335 PM CDT Thu Jul 03 2025
Areas affected...Portions of western/central North Dakota...far
eastern Montana...northeast Wyoming...and northwest South Dakota
Concerning...Severe potential...Watch possible
Valid 032035Z - 032230Z
Probability of Watch Issuance...60 percent
SUMMARY...Scattered storms possible this afternoon/evening, posing a
threat for large hail, damaging winds, and perhaps a tornado. Watch
issuance is possible.
DISCUSSION...Clear skies throughout the afternoon have allowed
surface temperatures to rise upper 80s and low 90s F amid a
relatively moist low-level airmass, characterized by dew point
temperatures in the low to mid 50s in northeast Wyoming/southeast
Montana to the mid/upper 60s and a few 70 F obs across North Dakota.
This is resulting in a west-east instability gradient ranging from
500-3000 J/kg. Visible satellite shows an area of deepening
convection forming in northeast Wyoming, likely in association with
an approaching mid-level trough.
The expectation is for the aforementioned convection to mature and
become more widespread, as forcing for ascent continues to
overspread the region. Scattered storms are expected, though
intensity may be somewhat limited in the short-term due to
relatively weaker instability/shear in proximity. As storms move
northeast with time, they should encounter greater instability while
deep-layer shear increases with the approaching wave. Meanwhile,
isolated storm development is possible across western/central North
Dakota. Forecast soundings/obs indicate convective temperatures in
the mid-90s F, which is supported by some areas of deepening
convection across the state.
Initial storms will likely be cellular in nature, posing a threat
for large hail and perhaps a tornado. With time, storms by grow
upscale, posing more of a threat for damaging winds. Given this
severe storm potential, watch issuance is possible later this
afternoon/evening for parts of the region.
..Karstens/Mosier.. 07/03/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...ABR...BIS...UNR...BYZ...GGW...
LAT...LON 44100432 43730551 43880599 45110588 46680514 48290388
48800218 48950134 48240068 47060061 45960143 45420189
45110230 44100432
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
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