MESOSCALE PRECIPITATION DISCUSSION 0340
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
824 PM EDT SUN JUN 12 2016
 
AREAS AFFECTED...NORTHERN CO...SOUTHEAST WY 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 130015Z - 130400Z
 
SUMMARY...THUNDERSTORMS WITH HEAVY RAIN WILL EXPAND IN COVERAGE
OVER THE NEXT COUPLE OF HOURS WITH SOME FLASH FLOODING POSSIBLE.

DISCUSSION...A SHORTWAVE TROUGH LIFTING NORTHEAST ACROSS NORTHWEST
CO AND SOUTHWEST WY IS HELPING TO GENERATE AND EXPAND FAIRLY
SLOW-MOVING CLUSTERS OF SHOWERS AND THUNDERSTORMS DOWN THE FRONT
RANGE FROM SOUTHEAST WY DOWN INTO NORTHERN CO.

THE AIRMASS ALONG AND EAST OF THE FRONT RANGE IS AT LEAST MODESTLY
UNSTABLE WITH MLCAPE VALUES LOCALLY OF 1000 TO 1500 J/KG...AND
PWATS ARE CLOSE TO 1 INCH AND THIS WILL PROVIDE SUFFICIENT
THERMODYNAMIC SUPPORT TO SUSTAIN THE CONVECTIVE ACTIVITY THROUGH
THE EVENING HOURS.

THE CONVECTION MAY ATTAIN A GREATER DEGREE OF ORGANIZATION BY LATE
EVENING AS THE EJECTING SHORTWAVE AND PRESENCE OF A COLD FRONT
HELP TO FOCUS THE THUNDERSTORM ACTIVITY A BIT FARTHER EAST WHERE
THERE WILL BE SOMEWHAT BETTER MOISTURE AND INSTABILITY POOLED
ALONG WITH CONVERGENT FLOW IN VICINITY OF THE FRONT. A CONSENSUS
OF THE HIRES GUIDANCE DOES SUPPORT THIS EVOLVING SCENARIO.

ALREADY RAINFALL RATES HAVE BEEN EXCEEDING 1 INCH/HR...AND IT IS
EXPECTED THAT AS MUCH AS 2 TO 4 INCHES WITH ISOLATED HEAVIER
TOTALS MAY OCCUR THROUGH ABOUT 04Z. THIS MAY RESULT IN SOME FLASH
FLOODING AND ALREADY THERE HAVE BEEN AT LEAST SOME RUNOFF PROBLEMS
REPORTED.

ORRISON

ATTN...WFO...BOU...CYS...

ATTN...RFC...MBRFC...

LAT...LON   41990451 41850409 40660397 39690412 39320450 
            39540508 40200509 40280502 40610504 41260504