MESOSCALE PRECIPITATION DISCUSSION 0333
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1225 AM EDT SUN JUN 12 2016
 
AREAS AFFECTED...MUCH OF ND 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 120425Z - 120910Z
 
SUMMARY...A GROWING MCC ACROSS ND COULD EXHIBIT CELL
MERGERS/TRAINING BANDS OVER THE NEXT FEW HOURS.  FLASH FLOODING IS
A CONCERN.

DISCUSSION...A BROADENING AREA OF COOLING CLOUD TOPS HAS BEEN
ENVELOPING ND AS OF LATE AS A FORMING MCC BRIDGES ACROSS FROM
EASTERN MT INTO CENTRAL ND.  PRECIPITABLE WATER VALUES ARE
1.3-1.5" PER GPS DATA, WITH LOCALLY HIGHER VALUES POSSIBLE HINTED
AT BY RECENT RAP RUNS.  THIS IS 2-3 SIGMAS ABOVE THE MEAN FOR
MID-JUNE.  INFLOW AT 850 HPA OF 35-55 KTS IS SEEN IN AREA VAD WIND
PROFILES, WHICH IS LURING SIGNIFICANT INSTABILITY -- ON THE ORDER
OF 3000-5500 J/KG MUCAPES -- INTO THE REGION.

THE MESOSCALE GUIDANCE IS MAINLY TOO FAR NORTH NEAR THE
INTERNATIONAL BORDER WITH THE THUNDERSTORM ACTIVITY.  EVEN SO,
THERE IS A SIGNAL IN THE NON-RAPID REFRESH GUIDANCE (WHICH APPEARS
TOO LIGHT) NEARBY FOR 2-3" OF RAIN, WHICH COULD FALL QUICKLY. 
SHOULD CELLS MERGE OR TRAIN, 2" AN HOUR RAIN RATES ARE POSSIBLE. 
THE 18Z SSEO NEIGHBORHOOD PROBABILITIES ADVERTISE 50%+ CHANCE OF
EXCEEDING THE RELATIVELY LOW FLASH FLOOD GUIDANCE VALUES AS LATE
AS 10Z.  DESPITE THE LOW VALUES, AREA FORECAST OFFICES REPORT
SOILS ARE NOT OVERLY MOIST/SATURATED AT THE PRESENT TIME.  WHILE
FORWARD PROPAGATING CONVECTIVE VECTORS SHOW AN EAST TO
EAST-NORTHEAST MOTION TO ORGANIZED CONVECTION, SOUTHEASTERLY FLOW
AT 850 HPA IS LIKELY TO HINDER SIGNIFICANT EASTWARD MOTION.  THERE
COULD BE PERIODS OF SOUTH TO NORTH TRAINING WITHIN THIS AREA, AS
CONVECTION HAS BEEN MAINLY MOVING WITH THE MEAN 850-400 HPA WIND. 
UNCERTAINTY IS GREATER THAN NORMAL HERE CONSIDERING THE GUIDANCE
SPREAD AND THE HIGH 700 HPA TEMPERATURES (12C+), WHICH IMPLY A
CAPPING INVERSION NEARBY.

ROTH

ATTN...WFO...ABR...BIS...BYZ...FGF...GGW...UNR...

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

LAT...LON   49109953 49019853 48469722 47729673 46829660 
            45909656 45829986 45910413 47560465 48750451 
            49040414 49070247