Flash Flood Guidance
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000
AWUS01 KWNH 062150
FFGMPD
WYZ000-UTZ000-IDZ000-070249-

MESOSCALE PRECIPITATION DISCUSSION 0315
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
549 PM EDT MON JUL 06 2015

AREAS AFFECTED...SOUTHEAST IDAHO...SOUTHWEST WYOMING...NORTHEAST
UTAH

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 062149Z - 070249Z

SUMMARY...SLOW MOVING CELLS CAPABLE OF 1-1.25"/HR RATES COULD LEAD
TO POSSIBLE FLASH FLOODING.  SOME CELLS MAY REDEVELOP ON HIGHER
TERRAIN FOR INCREASED POTENTIAL.

DISCUSSION...WV LOOP SHOWS A SUBTLE SHORTWAVE BETWEEN FLOWS ACROSS
SOUTHERN IDAHO MOVING EAST VERY SLOWLY.  THIS SHORTWAVE WILL
PROVIDE GOOD PVA FOR INCREASED UVVS DOWNSTREAM...AND A FORECAST
INCREASE OF 700MB FLOW OUT OF THE NORTHWEST WILL STRENGTHEN TROF
ACROSS SOUTHEAST IDAHO INTO NORTHERN UTAH FOR INCREASED
CONVERGENCE AND CONTINUED MOISTURE POOLING ACROSS THE DISCUSSION
AREA TO MAINTAIN ORGANIZED THUNDERSTORMS.  ADDITIONALLY RAP
FORECAST SOUNDINGS INDICATE AMPLE INSTABILITIES WITH MUCAPES IN
THE 1000-1500 J/KG RANGE FOR STRONG CORES AND EFFICIENT RAINFALL
PRODUCTION. WITH THE GPS NETWORK AND GOES SOUNDER SHOWING
INCREASING TOTAL PWATS INTO THE 1.1-1.2"/RANGE...RATES IN EXCESS
OF 1"/HR ARE LIKELY. CURRENT VISIBLE LOOP SHOWS ACTIVE LINE OF
CONVECTION ACROSS SOUTHEAST IDAHO AND ISOLATED STRONG CELLS
BEGINNING TO MERGE ACROSS THE NORTHERN GREAT DIVIDE BASIN INTO THE
SOUTHERN WIND RIVER MOUNTAINS. FLASH FLOODING IS POSSIBLE GIVEN
THE SLOW CELL MOTIONS AND RATES IN EXCESS OF 1"/HR...WITH HIGHER
POTENTIALS WHERE MERGERS OCCUR...AND HIGHER TERRAIN/OROGRAPHIC
COULD HANG OR ANCHOR CONVECTIVE DEVELOPMENT IN THE SHORT TERM.

FURTHER SOUTH...A WEAK SHORTWAVE/SHEAR AXIS IS LIFTING OUT OF
ARIZONA IN TO SOUTHERN UTAH...THIS WILL INCREASE SOUTHWESTERLY
FLOW AND MOISTURE TRANSPORT ACROSS THE UINTAS. CURRENTLY THE
UINTAS ARE ALONG THE NORTHWEST SIDE OF MIDDLE LEVEL RIDGE AXIS AND
IN THE RIGHT ENTRANCE OF THE ENHANCING 50 KT UPPER LEVEL JET
PROVIDING GOOD UPPER LEVEL SUPPORT.  CELLS HAVE DEVELOPED AND HAVE
THE POTENTIAL FOR CONTINUED UPSTREAM BACKBUILDING WITH THE
OROGRAPHIC LIFT AND INCREASING WINDS IN ADVANCE OF THE SHORTWAVE
AXIS. NUMEROUS HI-RES MODELS INDICATE A VERY SMALL AREA ALONG THE
EASTERN UNITAS FOR OVER 2" POSSIBLE...GIVEN AVAILABLE MOISTURE AND
PERSISTENCE THROUGH TO 00Z...THAT THERE MAY EVEN BE EVEN ISOLATED
HIGHER TOTALS INCREASING THE FLASH FLOOD THREAT HERE AS WELL.

GALLINA

...PLEASE SEE WWW.WPC.NCEP.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...GJT...PIH...RIW...SLC...

ATTN...RFC...CBRFC...MBRFC...NWRFC...

LAT...LON   43551052 43210915 42540831 41410880 40380954
            40111043 40501137 40961157 41521173 42301268
            43141198



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