MESOSCALE PRECIPITATION DISCUSSION 0187
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
625 PM EDT FRI JUL 11 2014
 
AREAS AFFECTED...NORTHERN UT...SOUTHEAST ID...WESTERN WY 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 112215Z - 120200Z
 
SUMMARY...SLOW-MOVING THUNDERSTORMS OVER THE HIGHER TERRAIN
FOSTERING SHORT-TERM FLASH FLOOD CONCERNS.

DISCUSSION...NUMEROUS SHOWERS AND THUNDERSTORMS HAVE DEVELOPED AND
CONTINUE TO EXPAND SOMEWHAT IN COVERAGE OVER THE HIGHER TERRAIN OF
FAR SERN ID...NERN UT AND INTO WRN WY AS A SHORTWAVE TROF LIFTING
THROUGH NERN UT ATTM CONTINUES TO ADVANCE ENEWD. AN ANOMALOUSLY
MOIST AND UNSTABLE AIRMASS IS IN PLACE OVER THESE AREAS. IN
FACT...THE LATEST GPS DERIVED PWAT FOR KSLC IS 1.34 INCHES...WHICH
IS ABOUT 2.5 STD ABOVE NORMAL.

STRONG DIURNAL HEATING COUPLED WITH OROGRAPHIC FORCING AND THE
AFOREMENTIONED SHORTWAVE TROF SHOULD YIELD AN ADDITIONAL EXPANSION
OF SHOWERS AND THUNDERSTORMS OVER THE NEXT FEW HOURS...WITH A
LIKELIHOOD OF CELL-MERGERS. THE OVERALL STORM MOTION IS QUITE WEAK
AND GENERALLY ON THE ORDER OF 5 TO 10 KTS. THIS COUPLED WITH THE
ANOMALOUSLY MOIST COLUMN SHOULD FAVOR LOCALLY HVY RAINFALL RATES
WITH SHORT-TERM AMOUNTS OF A COUPLE OF INCHES POSSIBLE.

THESE RAINS INVOF OF HIGHER TERRAIN WILL PROMOTE A THREAT FOR
FLASH FLOODING THROUGH THE EVENING. WILL CONTINUE TO MONITOR.

ORRISON

ATTN...WFO...RIW...GJT...TFX...SLC...PIH...BOI...LKN...

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

LAT...LON   41930835 40890911 40271044 40411144 41191203 41791239
            41761299 41771347 41781411 42431401 43451327 44351243
            44901098 44950981 44610809 44120668 43930735 43790821
            43400893 42790892 41930835