MESOSCALE PRECIPITATION DISCUSSION 0386
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
423 AM EDT SUN JUL 26 2015
AREAS AFFECTED...SOUTHEAST NEB...SOUTHWEST IA...NORTHWEST MO
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE
VALID 260822Z - 261230Z
SUMMARY...TWO GROUPS OF SHOWERS AND THUNDERSTORMS...EACH CAPABLE
OF PRODUCING HEAVY RAINFALL...WILL INCREASE THE RISK OF FLASH
FLOODING THROUGH EARLY SUNDAY MORNING.
DISCUSSION...SHOWERS AND THUNDERSTORMS HAVE BEEN FORMING AND
BECOMING MORE NUMEROUS OVER PARTS OF SOUTHEAST NEBRASKA AND
NORTHEAST KS EARLY THIS MORNING IN A REGION OF MOISTURE FLUX
CONVERGENCE. THESE STORMS WILL BE CAPABLE OF PRODUCING HEAVY
RAINFALL OVER AN AREA WHERE FLASH FLOOD GUIDANCE HAS BEEN LOWERED
BY RAINS OVER THE PAST FEW DAYS.
A SECOND AREA OF CONVECTION HAS BEEN BUILDING STEADILY TO THE
SOUTH FROM NORTHWEST IA AND NORTHEAST NEB. CONVECTION WAS
BECOMING MORE ACTIVE HERE BASED ON CLOUD TOP COOLING SEEN IN IR
SATELLITE IMAGERY...WHILE THE LEADING EDGE OF THE COLD POOL WAS
VISIBLE ON IR SATELLITE IMAGERY. WHILE THE COLD POOL WOULD HELP
KEEP THE STORMS PROPAGATING ALONG STEADILY...THE BOUNDARY COULD
ALLOW SOME INTERACTION WITH THE STORMS OVER SOUTHEAST NEB AND
NORTHEAST KS WHICH RESULTS IN ENHANCED RAINFALL RATES.
RECENT RUNS OF THE HIGH RES CONVECTION ALLOWING MODELS HAVE
FAVORED THIS AREA FOR HEAVY RAINFALL...WITH RAINFALL RATES OF 2
INCHES PER HOUR OR MORE. THIS WOULD BE ENOUGH FOR FLASH FLOODING
OVER THE SOUTHEAST CORNER OF NEB INTO FAR NORTHERN MO WHERE THE
FLASH FLOOD GUIDANCE IS LOWEST...BUT ALSO OVER PARTS OF SOUTHERN
IA GIVEN THE POSSIBILITY OF HIGH RAINFALL RATES.
BANN
ATTN...WFO...DMX...EAX...OAX...TOP...
ATTN...RFC...MBRFC...NCRFC...
LAT...LON 42899302 41979241 39809316 39129361 38769495
39109557 39749601 40609676 41449624 42029466
Last Updated: 423 AM EDT SUN JUL 26 2015