MESOSCALE DISCUSSION 1070

        MESOSCALE DISCUSSION 1070     NWS STORM PREDICTION CENTER NORMAN OK     1246 PM CDT TUE JUN 05 2012          AREAS AFFECTED...NERN UT...SWRN WY...FAR SERN ID          CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY           VALID 051746Z - 052015Z          PROBABILITY OF WATCH ISSUANCE...5 PERCENT          SUMMARY...A VERY ISOLATED SVR WIND THREAT WILL EXIST WITH A FEW     THUNDERSTORMS THIS AFTERNOON...AND A WW IS NOT NEEDED.          DISCUSSION...RECENT WATER VAPOR LOOP REVEALS A STRONG DEEP TROUGH     OVER THE WRN U.S. THAT IS BECOMING INCREASINGLY NEGATIVELY TILTED.     STRONG DEEP MERIDIONAL FLOW LEADS THE TROUGH AXIS ACROSS PARTS OF     THE CNTRL GREAT BASIN...WITH SALT LAKE CITY VWP DATA INDICATING     30-50 KT OF SLY FLOW WITHIN THE 2-4-KM-AGL LAYER. NEAR AND AHEAD OF     THE SFC COLD FRONT ATTENDANT TO THE TROUGH...ABUNDANT     INSOLATION/DIABATIC HEATING IS SUPPORTING STEEPENING     LOW-TO-MID-LEVEL LAPSE RATES AS SFC TEMPERATURES WARM THROUGH THE     70S. THIS IS BEING MANIFESTED AS SFC GUSTS REACHING/EXCEEDING 40 MPH     PER AREA OBSERVATIONS.          STRONG LARGE-SCALE FORCING FOR ASCENT ASSOCIATED WITH THE     TROUGH...MARKED BY 500-MB HEIGHT FALLS IN EXCESS OF 90 GEOPOTENTIAL     METERS PER 12 HRS...AND THE AFOREMENTIONED DIABATIC HEATING WILL AID     IN FURTHER DESTABILIZATION INTO THE AFTERNOON.     WHILE DEEP MOISTURE IS VERY SCARCE...WITH PW VALUES OF 0.3-0.4 INCH     PER GPS DATA...WATER VAPOR IMAGERY DEPICTS THE SRN EXTENT OF THE     DCVA-RELATED LOBE OF ASCENT ACCOMPANYING THE TROUGH ENTERING NWRN UT     AND S-CNTRL ID. AS VERTICAL MIXING ALLOWS SOME OF THIS MOISTURE TO     BE DISTRIBUTED THROUGH THE WELL MIXED BOUNDARY LAYER...SBCAPE VALUES     OF 150-250 J/KG SHOULD DEVELOP WITHIN A ZONE NEAR AND JUST AHEAD OF     THE FRONT. AND...WITH FRONTAL ASCENT COMBINED WITH OROGRAPHIC     EFFECTS -- E.G. INVOF THE WASATCH RANGE AND UINTA MOUNTAINS --     MESOSCALE ASCENT WILL EXIST TO SUPPORT THE POTENTIAL INITIATION OF     VERY ISOLATED...SHALLOW...PULSE CONVECTION AFTER 1900Z.          WHILE CONVECTION MAY CONTAIN LITTLE...IF ANY...LIGHTNING...ITS     ACCOMPANYING CONVECTIVE MASS TRANSPORT PROCESSES AUGMENTED BY     EVAPORATIVE COOLING PROCESSES WITHIN THE DEEP BOUNDARY LAYER     COMBINED WITH THE STRONG BACKGROUND FLOW/TIGHT SFC PRESSURE GRADIENT     WILL SUPPORT A THREAT FOR VERY ISOLATED SVR WIND GUSTS WITH DRY     MICROBURSTS THIS AFTERNOON. THE THREAT IS EXPECTED TO REMAIN TOO     ISOLATED TO WARRANT A SVR TSTM WATCH IN THE ABSENCE OF GREATER     MOISTURE/BUOYANCY.          ..COHEN/MEAD.. 06/05/2012               ATTN...WFO...RIW...GJT...SLC...PIH...