MESOSCALE PRECIPITATION DISCUSSION 0699
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1004 PM EDT SAT SEP 24 2016
AREAS AFFECTED...NORTHEAST KS...NORTHWEST MO INTO CENTRAL IA
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY
VALID 250205Z - 250600Z
SUMMARY...CONVECTION REDEVELOPING IN A HIGH MOISTURE CONTENT
AIRMASS IS EXPECTED TO CONTINUE TRAINING IN A FAST UNIDIRECTIONAL
FLOW...RESULTING IN FLASH FLOODING INTO THE EARLY MORNING HOURS.
DISCUSSION...REINVIGORATED CONVECTION IS LOCATED IN AN AXIS OF
1000-1500 J/KG MLCAPE. THE IR LOOP SHOWED COOLING TOPS WITH THE
STRENGTHENING CONVECTION...WHICH IS TAPPING A RIBBON OF 2.00+ INCH
PRECIPITABLE WATER AIR (WHICH IS BETWEEN TWO AND THREE STANDARD
DEVIATIONS ABOVE THE MEAN). THE KTWX RADAR SHOWED HOURLY RAINFALL
RATES BETWEEN 1.50 AND 2.00 INCHES ACROSS SHAWNEE COUNTY KS WITH
THE CURRENT ACTIVITY.
THE CONVECTION IS EXPECTED TO CONTINUE TO TRAIN ACROSS NORTHEAST
KS...NORTHWEST MO INTO CENTRAL IA THROUGH 06Z. THE LATEST RAP
SHOWED SUFFICIENT INSTABILITY (WITH MUCAPE VALUES REMAINING NEAR
1000 J/KG) IN PLACE THROUGH ABOUT 05Z...AFTER WHICH THE
INSTABILITY STARTS TO BECOME EXHAUSTED.
THE LATEST HRRR/EXPERIMENTAL HRRR INDICATED THE POTENTIAL FOR
LOCAL 2-4 INCH RAINFALL AMOUNTS...WITH THE HIGHEST TOTAL EXPECTED
OVER FAR NORTHEAST KS AND FAR NORTHWEST MO...WHERE THE BEST
CONVECTION IS CURRENTLY LOCATED. GIVEN THE RAINFALL RATES SEEN ON
THE KTWX RADAR...THESE AMOUNTS SEEM PLAUSIBLE...ESPECIALLY WHERE
TRAINING PERSISTS.
FOR THE MOST PART...ONE AND THREE HOUR FLASH FLOOD GUIDANCE VALUES
ARE ABOVE 2.00 INCHES ACROSS NORTHEAST KS AND NORTHWEST MO (THOUGH
THIS COULD CHANGE WITH THE HEAVY RAIN OCCURRING)...SO TRAINING
WOULD BE NECESSARY TO MAINTAIN THE FLASH FLOOD THREAT. FURTHER
NORTHEAST INTO CENTRAL IA...THE INSTABILITY IS NOT AS ROBUST...
BUT HAS INCREASED IN THE WAKE OF THE WARM FRONTAL PASSAGE. WHILE
THE HIGH RESOLUTION GUIDANCE IS INDICATING LOCAL 1-2 INCH RAINFALL
AMOUNTS...THE FLASH FLOOD GUIDANCE VALUES HERE ARE LOWER (DUE TO
HEAVY RAINFALL THE PAST FEW DAYS). FOR THIS REASON...THE MPD WAS
EXTENDED INTO CENTRAL IA.
HAYES
ATTN...WFO...DMX...EAX...ICT...OAX...TOP...
ATTN...RFC...ABRFC...MBRFC...NCRFC...
LAT...LON 42349417 42079327 41719304 41389317 38979498
38279590 38079645 38019679 38389704 39069683
39709641 40159615 41989473
Last Updated: 1004 PM EDT SAT SEP 24 2016