431
ACUS11 KWNS 201934
SWOMCD
SPC MCD 201933
UTZ000-WYZ000-IDZ000-NVZ000-ORZ000-202130-
MESOSCALE DISCUSSION 1213
NWS STORM PREDICTION CENTER NORMAN OK
0233 PM CDT SAT JUN 20 2026
AREAS AFFECTED...NORTHERN UTAH INTO SOUTHEAST IDAHO
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 201933Z - 202130Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...ISOLATED STRONG TO SEVERE DOWNBURST WINDS WILL BE POSSIBLE
THROUGH EARLY EVENING ACROSS THE NORTHERN GREAT BASIN INTO FAR
SOUTHWEST WYOMING. THIS THREAT SHOULD REMAIN SUFFICIENTLY ISOLATED
TO PRECLUDE WATCH ISSUANCE.
DISCUSSION...THE EARLY STAGES OF THUNDERSTORM INITIATION ARE ONGOING
ACROSS NORTHERN NV AND INTO ADJACENT PORTIONS OF SOUTHERN ID AND
NORTHWEST UT. THIS ACTIVITY IS LARGELY BEING DRIVEN BY LARGE-SCALE
ASCENT IN PROXIMITY TO A MID-LEVEL VORTICITY MAXIMUM EVIDENT IN
RECENT WATER-VAPOR IMAGERY, AND IS BEING AIDED BY LOCALIZED
OROGRAPHIC ASCENT WITHIN THE HIGHER TERRAIN FEATURES. ACROSS MUCH OF
NORTHEAST NV INTO UT/ID, TEMPERATURES ARE WARMING INTO THE MID 70S
TO LOW 80S WITH DEWPOINT DEPRESSIONS INCREASING INTO THE 30-40 F
RANGE, INDICATIVE OF DEEP BOUNDARY-LAYER MIXING. RECENT RAP
MESOANALYSES CORROBORATE THESE OBSERVATIONS AND SUGGEST 0-3 KM LAPSE
RATES ARE NEARLY DRY ADIABATIC.
WHILE DRY LOW-LEVEL CONDITIONS ARE LIMITING OVERALL BUOYANCY, THE
BOUNDARY-LAYER THERMODYNAMIC CONDITIONS ARE FAVORABLE FOR DOWNDRAFT
ACCELERATIONS CAPABLE OF PRODUCING STRONG TO SEVERE DOWNBURST WINDS.
ADDITIONALLY, 20-30 KNOTS OF BULK SHEAR THROUGH THE CAPE-BEARING
LAYER SHOULD PROVIDE SOME STORM LONGEVITY, FURTHER SUPPORTING THE
POTENTIAL FOR STRONG/SEVERE WINDS. IN GENERAL, THUNDERSTORM COVERAGE
SHOULD REMAIN ISOLATED TO PERHAPS WIDELY SCATTERED, AND THE
DOWNBURST WIND THREAT ASSOCIATED WITH ANY PARTICULAR STORM SHOULD
REMAIN RELATIVELY TRANSIENT (10-30 MINUTES). THESE FACTORS LIMIT
CONFIDENCE IN THE NEED FOR A WATCH.
..MOORE/HART.. 06/20/2026
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
ATTN...WFO...RIW...SLC...PIH...BOI...LKN...
LAT...LON 41531057 41021089 40531174 40031345 39981385 40021433
40441523 40811592 40871709 40931777 41061807 41201818
41511820 41861812 42031794 42181770 42331727 42501398
42661310 43191149 43181097 42971074 42511070 41531057
MOST PROBABLE PEAK WIND GUST...55-70 MPH
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