MESOSCALE PRECIPITATION DISCUSSION 0366
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
521 AM EDT TUE JUN 21 2016
 
AREAS AFFECTED...EASTERN NE...FAR SOUTHWEST IA...PORTIONS OF
NORTHERN AND CENTRAL MO 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 210920Z - 211400Z
 
SUMMARY...CONVECTION TRAINING FROM EASTERN NE AND SOUTHWEST IA
OVER NORTHERN AND CENTRAL MO WILL TRACK OVER AREAS THAT RECEIVED
HEAVY RAINFALL OVERNIGHT... RESULTING IN FLASH FLOOD THREAT THIS
MORNING.

DISCUSSION...REGIONAL RADARS SHOW CONVECTION FORMING OVER PORTIONS
OF EASTERN NE INTO FAR SOUTHWEST IA AND NORTHERN MO EARLY THIS
MORNING. THE CONVECTION IS FORMING IN AN AXIS OF 1000-2000 J/KG OF
MUCAPE STRETCHING CENTRAL NE INTO CENTRAL MO...WHERE PRECIPITABLE
WATER VALUES PEAK NEAR 2.10 INCHES OVER NORTH CENTRAL MO (PER THE
LATEST RAP ANALYSIS). THE IR LOOP SHOWED A BURST OF DEEP
CONVECTION OVER NORTH CENTRAL MO...WITH CLOUD TEMPERATURES NEAR
MINUS 72 CELSIUS.

THE CONVECTION IS TRACKING SOUTHEAST ALONG THE AXIS...WHICH TAKES
IT OVER PORTIONS OF NORTH CENTRAL MO...WHERE THE KEAX RADAR
INDICATED THAT AS MUCH AS 3 TO 5 INCHES OF RAIN HAD ALREADY FALLEN
MON NIGHT INTO EARLY THIS MORNING. THE CONVECTION OVER EASTERN NE
AND FAR SOUTHWEST IA IS ELEVATED...AND AT LEAST SOME OF THAT
CONVECTION IS PRODUCING HAIL (BASED ON THE AMOUNT OF DRY AIR IN
THE RAP SOUNDINGS OVER THESE AREAS). THE KEAX RADAR INDICATED
HOURLY RAINFALL RATES NEAR 2.00 INCHES IN DAVIES COUNTY
MO...THOUGH MESONET OBSERVATIONS IN THAT AREA SUGGEST THESE
AMOUNTS COULD BE OVERESTIMATED BY NEARLY 50 PERCENT. 

THERE IS A STRONG SIGNAL IN THE HIGH RESOLUTION GUIDANCE
(INCLUDING THE 07Z HRRR/EXPERIMENTAL HRRR/HRRR PARALLEL) FOR THE
INSTABILITY AXIS TO REMAIN IN PLACE THROUGH AT LEAST 13Z...SO THE
CONVECTION IS EXPECTED TO TRAIN ACROSS EASTERN NE AND FAR
SOUTHWEST IA INTO NORTHERN AND CENTRAL MO.

THE 07Z HRRR WAS BY FAR THE MOST BULLISH WITH RAINFALL AMOUNTS
WITH THE TRAINING CONVECTION...SHOWING AN AREA OF 4 TO 6 INCHES OF
RAIN IN NORTHERN MO...NEAR KCDJ. WHILE THESE AMOUNTS MAY BE THE
UPPER LIMIT OF WHAT MIGHT OCCUR...THE 07Z EXPERIMENTAL HRRR/06Z
HRRR PARALLEL SUGGEST 2 TO 4 INCHES OF RAINFALL IS POSSIBLE
THROUGH 14Z...WITH THE HIGHEST AMOUNTS OVER NORTH CENTRAL MO. 

THE ADDITIONAL RAINFALL OVER AREAS THAT RECEIVED HEAVY RAIN
OVERNIGHT COULD RESULT IN AN INCREASING FLASH FLOOD THREAT...
PARTICULARLY OVER PORTIONS OF NORTH CENTRAL MO.

HAYES

ATTN...WFO...DMX...EAX...LSX...OAX...SGF...TOP...

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

LAT...LON   41689664 41389495 39979190 38789061 38079104 
            38439334 39479496 40539635 40779666 40949700 
            41329706