MESOSCALE PRECIPITATION DISCUSSION 0186
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
443 PM EDT SUN MAY 08 2016
 
AREAS AFFECTED...SW WYOMING...EXT N UTAH...EXT SE IDAHO 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 082045Z - 090145Z
 
SUMMARY...ISOLATED FLASH FLOOD THREAT DUE TO POTENTIAL TRAINING
WITH RELATIVELY WET ANTECEDENT CONDITIONS.  

DISCUSSION...WV LOOP/RAP ANALYSIS SHOWS A VERY STRONG SHORTWAVE
LOBE AND ASSOCIATED HEIGHT FALLS (30-60 DM/12HRS) ROTATING WEST
ACROSS NE WY ATTM.  DEEPENING SURFACE LOW AND ASSOCIATED
ISALLOBARIC FLOW AS WELL AS FAIRLY CONFLUENT LOW TO MIDLEVEL FLOW
IN CHANNELING WHAT LIMIT MOISTURE THERE IS (.5-.6" MAX TPW) ACROSS
THE ABSAROKA, TETON AND NORTHERN WIND RIVER RANGES TO FEED THE
NORTHERN SUBLETTE COUNTY VALLEY FOR NEARLY SATURATED LOW LEVEL
PROFILES PER 18Z RAP.  LOW LEVEL TDS IN THE MID 40S AND WITH SOME
SOLAR INSOLATION CAPE VALUES IN THE 500-750 J/KG RANGE ARE
CURRENTLY PRESENT FOR CELL DEVELOPMENT.  ELEVATION IS CURRENTLY
ANCHORING DEVELOPMENT ALONG THE WESTERN FLANKS OF THE ABSAROKA AND
WIND RIVER RANGES WITH SOUTHERLY/SELY FLOW UP THE VALLEYS FEEDING
THESE UPDRAFTS THIS SHOULD CONTINUE TO SUPPORT ANY REDEVELOPMENT
IN SIMILAR/SAME LOCATIONS AS EACH UPDRAFT CORE MOVES OFF INTO THE
VALLEY MAINTAINED BY THE LOW LEVEL FLOW AND INSTABILITY IN PLACE. 
DEEP UNIDIRECTIONAL FLOW OF 20-30 KTS WILL SUPPORT TRAINING AND
RELATIVE SLOW CELL MOTIONS.  THOUGH MOISTURE IS LIMITED...RATES UP
TO .5"/HR ARE POSSIBLE ESPECIALLY IF CONVECTIVE STRENGTH INCREASES
OVER THE NEXT FEW HOURS.  THOUGH LACK OF HIGH MOISTURE VALUES MAY
BE THE  LIMITING FACTOR TOWARD THIS DEEPER GROWTH...AS CELLS ARE
ONLY TO -45C ATTM AND THEREFORE CONFIDENCE IN THE OVERALL SETUP
FOR FLASH FLOODING REMAINS WITH SOME QUESTIONS.

HI-RES CAMS SUPPORT THE IDEA OF STRONGER UPDRAFTS THROUGH SUBLETTE
COUNTY AND SSWWARD INTO LINCOLN/NW SWEETWATER COUNTIES  WITH
FURTHER OROGRAPHIC ASCENT INTO THE NORTHERN UNITA AND WYOMING
RANGES POSSIBLE AS WELL PARTICULARLY LATER TOWARD EVENING. THESE
HI-RES CAMS SUCH AS THE NSSL-WRF...WRF-ARW AND NMMB ARE AGGRESSIVE
ENOUGH TO PRODUCE OVER 2" IN THE NEXT 6HRS.  THOUGH FFG VALUES
HAVE REBOUNDED...THIS MAY BE OVERDONE GIVEN RECENT ANOMALOUS RAIN
TOTALS.  RECENT HRRR AND ESRL EXPERIMENTAL HRRR HAVE TENDED TO BE
A BIT LESS AGGRESSIVE WITH TOTALS IN THE 1.25-1.75" RANGE WHICH
SEEMS MORE LIKELY GIVEN THE SETUP WITH A MUCH MORE NARROWED FOCUS
OF TRAINED/REPEAT CELL TRACKS.  ALL IN ALL THE CONFIDENCE IS
FAIRLY HIGH IN A TRAINING SETUP BUT MAGNITUDE IS MORE IN QUESTION. 

GALLINA

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

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

LAT...LON   44070922 43580859 43100887 42620924 41890966 
            41110996 40961056 41111127 42131135 42651116 
            43331073 43920981