ZCZC SPCSWOMCD ALL
ACUS11 KWNS 310707 
SPC MCD 310707 
SDZ000-NDZ000-310900-

Mesoscale Discussion 1760
NWS Storm Prediction Center Norman OK
0207 AM CDT Wed Jul 31 2024

Areas affected...Northwest to central SD and far south-central ND

Concerning...Severe potential...Watch possible 

Valid 310707Z - 310900Z

Probability of Watch Issuance...60 percent

SUMMARY...A threat for large hail and severe gusts, including
potential for significant severe, may occur as scattered storms
mature over northwest into north-central South Dakota. Some
uncertainty exists on timing of a sustained severe threat, so a
watch issuance is possible.

DISCUSSION...UDX VWP data confirm the presence of near 25-kt
southerly lower-level jet which is aiding in convection developing
across a portion of northwest into north-central SD. This appears to
be occurring to the north/west of a weak surface cyclone in vicinity
of Ziebach/Dewey counties. Upstream, a shortwave trough evident in
water vapor imagery near the Bighorn Mountains will likely enhance
large-scale ascent later this morning. The bulk of evening CAM
guidance suggests this will aid in a more sustained severe threat,
but the HRW-ARW indicated a more earlier threat which is better
timed to the ongoing development. The presence of a rather steep
lapse rate environment and adequate deep-layer shear for supercells
suggest that any sustained updrafts will have the potential to
produce large hail and severe gusts, which may become significant.
This should occur as convection impinges on increasingly larger
buoyancy emanating north from south-central/southeast SD.

..Grams/Guyer.. 07/31/2024

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...FSD...ABR...BIS...UNR...

LAT...LON   45430224 45880161 46240031 46019956 45499890 44819859
            44319851 44029900 44010056 44250191 44880236 45430224 

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