MESOSCALE PRECIPITATION DISCUSSION 0311
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
901 PM EDT FRI AUG 22 2014
 
AREAS AFFECTED...NORTHEASTERN CO/SOUTHWESTERN NE/EXTREME
NORTHWESTERN KS... 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 230100Z - 230545Z
 
SUMMARY...WIDESPREAD CONVECTION CONTINUES TO AFFECT MUCH OF THE
CENTRAL HIGH PLAINS WITH SEVERAL AREAS OF CELL MERGERS OCCURRING.
ALL OF THE ACTIVITY WILL MIGRATE NORTHWARD AHEAD OF A PRONOUNCED
SHORTWAVE DIGGING THROUGH THE SOUTHERN ROCKIES. STRONG UPPER
DIFFLUENCE IN THE JET SHOULD HELP MAINTAIN THE CONVECTION
OVERNIGHT IN SPITE OF THE RAPIDLY DIMINISHING CAPE PROFILES.

DISCUSSION...A BROAD AREA OF STRONG THUNDERSTORMS WERE OBSERVED
OVER MUCH OF EASTERN CO/WESTERN KS AND INTO SOUTHWESTERN NE. THE
ACTIVITY HAS GENERALLY BEEN FOLLOWING A SOUTH TO NORTH TRAJECTORY
WITH MANY REGIONS SEEING REPEAT CONVECTION INCLUDING MULTIPLE CELL
MERGERS. OVERALL THE INSTABILITY HAS WEAKENED ACROSS THE REGION
GIVEN CONVECTIVE OVERTURNING AND ANVIL DEBRIS OVER THE REGION.
HOWEVER...THE DYNAMICS WITH THE TROF CONTINUE TO OVERCOME THE LACK
OF CAPE WITH STRONG 850-700 MB UPSLOPE FLOW AND BROAD DIFFULENCE
ALOFT. THE EAST TO SOUTHEASTERLY FLOW WILL ALSO ADVECT THE MOISTER
AIR FROM THE PLAINS WHERE PWATS WERE ALMOST 2" AT TOPEKA KS PER
THE 00Z RAOB. FURTHER...THE SOUNDING OVER DENVER AT 00Z LOOKED
FAIRLY CONDUCIVE FOR HEAVY RAINFALL WITH A TALL/SKINNY CAPE
PROFILE AND SOUTHERLY UNIDIRECTIONAL FLOW FROM 700 MB UP TO THE
TROPOPAUSE.

THE HIGH-RESOLUTION MODEL AGREEMENT IS DECENT WITH HEAVY RAINFALL
IMPACTING THE AFFECTED REGION THROUGH 06Z. THE 12Z
HRW-ARW/HRW-NMMB AND 12Z SSEO MEAN/NSSL WRF SHOW SUFFICIENT
CLUSTERING IN THE COVERAGE OF HEAVY PRECIPITATION. THE IN-HOUSE
18Z NCASE AGREES WITH THIS IDEA WITH THE HIGHEST QPF PROBABILITIES
CENTERED OVER NORTHEASTERN CO AND UP INTO CENTRAL NE.


RUBIN-OSTER

ATTN...WFO...GID...LBF...GLD...BOU...CYS...

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

LAT...LON   40930399 41640348 42140259 42300192 42360055 42009959
            41389900 40419903 40079956 39980010 39940070 39900127
            39740172 39010254 38980366 39720411 40930399