MESOSCALE PRECIPITATION DISCUSSION 0185
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
629 PM EDT SAT MAY 07 2016
 
AREAS AFFECTED...CENT AND SE WYOMING...NE COLORADO...EXT W
NEBRASKA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 072230Z - 080330Z
 
SUMMARY...ENHANCING DEFORMATION ZONE ACROSS SE WY WILL CHANNEL MST
FLUX AND MDT TO HVY RAINFALL OVER THE NEXT FEW HOURS FOR POSSIBLE
FLASH FLOODING...CONTINUED FLASH FLOODING THREAT IN WIND RIVER
EASTERN FLANKS IS REDUCING WITH TIME BUT REMAINS POSSIBLE OVER THE
NEXT 4-6HRS GIVEN LOW FFG VALUES. 

DISCUSSION...WV LOOP SHOWS A SHARPENING TROF ACROSS N CO/SE WY/W
NEB WITH VIGOROUS SHORTWAVE ACTIVATING DEEP CONVECTION ACROSS NE
CO ATTM.  GIVEN STRONG NORTHERN JET OUT OF CENTRAL CANADA...THERE
IS A STRENGTHENING DEFORMATION ZONE/CHANNEL TOWARD THE WEST FROM
THE APEX IN NE CO.

CENTRAL WY...THIS HAS MAINTAINED THE COOL CONVEYOR BELT WITH
MODERATE MOISTURE FOCUSED DUE WEST ACROSS CENTRAL WY WITH 25-30 KT
OF FLOW WITH .75" TPWS ALLOWING FOR CONTINUED ASCENT ALONG THE
HIGHER TERRAIN PARTICULARLY EAST FACING SLOPES OF THE WIND RIVER
RANGE TO MAINTAIN MODERATE .5"/HR RATES.  THIS SHOULD PERSIST FOR
THE NEXT 3-4 HOURS AS EVENTUALLY NORTHERLY FLOW WILL DOMINATE IN
THE LOWER LEVELS DUE TO SURFACE LOW/SHORTWAVE TRACKING FURTHER
EAST.  STILL AN ADDITIONAL 1-2" OF RAIN OVER AREAS ALREADY
AFFECTED BY OVER 5" IN THE LAST 24HRS.

FURTHER EAST (SE WY/NE CO/W NEB)...SURFACE LOW IS TRANSITIONING
ENE ALONG FRONTAL BOUNDARY ACROSS NE CO INTO NW KS.  NORTH OF THE
BOUNDARY ISALLOBARIC STRENGTHENING OF LOW LEVEL MOIST FLOW ACROSS
W NEB PROVIDES EXCELLENT CONVERGENCE ALONG NUMEROUS
BOUNDARIES/OUTFLOWS AND MERGING CONVECTIVE CORES.  THIS IS
ALLOWING FOR MOISTENING OF THE LAPSE RATES AND GENERATING MORE
EFFICIENT RAINFALL.  AS THE SHORTWAVE MOVING EAST AND SHEARS...THE
DEFORMATION ZONE WILL ENHANCE AND REDUCE PROPAGATION VECTORS
ALLOWING FOR CELL MOITIONS TO CHANNEL ACROSS SE WY TOWARD THE
LARAMIE RANGE ENHANCING THE LIKELIHOOD OF TRAINING OF REMAINING
CONVECTIVE ELEMENTS LEADING TO LOCALIZED FLASH FLOODING THREATS
PARTICULARLY IN HIGHER TERRAIN. STRONGEST CELLS ON THE EASTERN
SIDE OF THE DISCUSSION AREA WILL REMAIN FED BY BEST INSTABILITY
BUT ALSO WILL PROPAGATE NORTH/NNE EVENTUALLY NORTH OF THE PLATTE
RIVER VALLEY INTO THE SAND HILLS AND THUS BE OF LITTLE FLASH
FLOODING THREAT. 

GALLINA 

ATTN...WFO...BOU...CYS...GLD...LBF...RIW...

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

LAT...LON   43670894 43570663 42210426 41910338 41030179 
            40510229 39830304 39600337 40380463 40650517 
            42040705 42340869 43410923