MESOSCALE PRECIPITATION DISCUSSION 0180
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
934 PM EDT SAT JUN 06 2015
 
AREAS AFFECTED......NORTHEAST NE/SOUTHEAST SD/SOUTHERN MN/NORTHERN
IA... 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 070135Z - 070700Z
 
SUMMARY...THE DEVELOPING MCS OVER NORTHEAST NE TRACKS ACROSS
SOUTHEAST SD...SOUTHERN MN AND NORTHERN IA THROUGH 06Z...PRODUCING
FLASH FLOODING. 

DISCUSSION...THE IR LOOP SHOWED RAPIDLY COOLING TOPS OVER
NORTHEAST NE...WITH CLOUD TOP TEMPERATURES NEAR -70 C. CONVECTION
WITH THE ORGANIZING MCS HAS EXPANDED GREATLY IN THE PAST HOUR...AS
A 30 TO 40 KNOT LOW LEVEL JET (PER REGIONAL VWP) CONTINUES TO
TRANSPORT 1.75+ PRECIPITABLE WATER AIR IN THE DEVELOPING COMPLEX.
AS MENTIONED EARLIER BY SAB...SATELLITE DERIVED RAINFALL RATES OF
2.00 TO 2.50 INCHES HAVE BE SEEN. KFSD RADAR HAD HOURLY RATES NEAR
2 INCHES AS WELL ACROSS NORTHEAST NE...BUT GIVEN THE HIGH CAPE
VALUES AND DRY AIR IN THE MID LEVELS... THE RADAR ESTIMATES COULD
BE HAIL CONTAMINATED.

THE MCS SHOULD CONTINUE TO STRENGTHEN THIS EVENING IN RESPONSE TO
THE STRONG LOW LEVEL JET AS IT TRACKS ACROSS SOUTHEAST SD...
SOUTHERN MN AND NORTHERN IA. DURING THIS TIME...INDIVIDUAL SEVERE
CELLS IN THE MCS COULD TURN RIGHT AND SLOW...INCREASING THE
POTENTIAL FOR FLASH FLOODING. IN ADDITION...TRAINING OF CELLS AS
THE MCS TRACKS NORTHEAST SHOULD RESULT IN FLASH FLOODING. THERE IS
A MULTI HIGH RESOLUTION MODEL SIGNAL FOR HEAVY RAINFALL WITH THE
MCS...MAINLY ACROSS SOUTHWEST MN AND NORTHERN IA THROUGH 06Z.

RAINFALL AMOUNTS OF 2 TO 4 INCHES ARE POSSIBLE ALONG THE TRACK OF
THE MCS...AND THE 12Z NSSL WRF SUGGEST LOCAL 6 INCH AMOUNTS ARE
POSSIBLE. FLASH FLOODING IS CONSIDERED LIKELY IN THIS
SCENARIO...WHICH IS SUPPORTED BY THE 18Z SSEO NEIGHBORHOOD
PROBABILITIES EXCEEDING 70 PERCENT OVER SOUTHWEST MN AND NORTHWEST
IA.

HAYES

ATTN...WFO...ARX...DMX...FSD...MPX...OAX...

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

LAT...LON   44329383 44329375 44319332 44219305 44089284 
            43979273 43869270 43759269 43589269 43229287 
            43019331 42729393 42479459 42389512 42339564 
            42239593 42329740 42709813 42699813 43439830 
            43489828 43619801 43989709 44199580 
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