MESOSCALE PRECIPITATION DISCUSSION 0341
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
900 PM EDT SUN JUN 12 2016
 
AREAS AFFECTED...NORTH TEXAS 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 130100Z - 130600Z
 
SUMMARY...CONCERNS ARE DEVELOPING FOR BACKBUILDING THUNDERSTORMS
WITH VERY HEAVY RAINFALL THROUGH THE EVENING HOURS.

DISCUSSION...LATE-DAY VIS IMAGERY SHOWS A VERY WELL-DEFINED AND
COMPACT MCV PERSISTING AND STILL SLOWLY MOVING EAST ACROSS
NORTH-CENTRAL TX. THE MCV HAS BEEN INTERACTING WITH A VERY MOIST
AND UNSTABLE AIRMASS POOLED ACROSS MUCH OF SOUTHEAST TX THAT
CONTINUES TO ADVECT NORTHWEST BACK TO AREAS FROM THE TX HILL
COUNTRY NORTHEAST UP TO THE RED RIVER VALLEY.

THERE IS EVIDENCE OF AN OUTFLOW BOUNDARY FOCUSED GENERALLY SW/NE
FROM JUST SOUTH OF BROWNWOOD AND NORTHEAST IN A WAVY FASHION TO
EAST OF TERRELL. A COMBINATION OF THIS WITH THE MCV...ALONG WITH
SOME GRADUAL INCREASE IN A NOCTURNAL S/SW LOW LEVEL JET BY LATE
EVENING SUGGESTS THAT CONVECTION SHOULD TEND TO PERSIST AND THERE
WILL BE A CONCERN FOR THE SOUTHERN AND EASTERN FLANKS OF THE MCV
TO BECOME EVEN MORE CONVECTIVELY ACTIVE WHERE THE LOW LEVEL JET
WILL BE INTERCEPTED BY THE OUTFLOW BOUNDARY. THIS IS AN EXCELLENT
SET-UP FOR BACKBUILDING AND REPEATING CELLS.

HIRES GUIDANCE GOING BACK TO THE 12Z CYCLE HAVE BEEN INDICATING A
SIGNAL FOR THIS TO OCCUR OVERNIGHT...WITH THE POTENTIAL FOR
CONCENTRATED/FOCUSED HEAVY RAINFALL AMOUNTS. THE WRF-ARW AND
WRF-NMMB EACH SUGGESTED THE POTENTIAL OF SEVERAL INCHES OF RAIN
THROUGH 06Z WITH MORE BEYOND THIS PERIOD. RECENT RUNS OF THE HRRRP
CONFIRM THIS THREAT. ADJUSTING FOR WHERE THE MCV IS SITUATED ALONG
WITH RELEVANT SURFACE BOUNDARIES...IT WOULD APPEAR THAT AN AREA
FROM WACO TO HILLSBORO...AND OVER TO AREAS JUST SOUTH OF TERRELL
WOULD STAND TO SEE THE HEAVIEST CONVECTIVE RAINFALL POTENTIAL.
AREAS WEST OF WACO AND IN THE SOUTHWEST FLANK OF THE MCV WILL NEED
TO BE MONITORED FOR CONVECTIVE DEVELOPMENT LATER IN THE EVENING AS
THE LOW LEVEL JET INCREASES HERE.

GIVEN PWATS OF NEAR 2 INCHES AND THE BACKBUILDING/REPEATING CELL
POTENTIAL...EXPECT VERY INTENSE RAINFALL RATES AND STORM TOTALS
THROUGH 06Z. RAINFALL AMOUNTS OF UP TO 6 INCHES WILL BE
POSSIBLE...AND SOME ISOLATED HEAVIER AMOUNTS. FLASH FLOODING IS
LIKELY.

ORRISON

ATTN...WFO...FWD...SHV...

ATTN...RFC...ABRFC...LMRFC...WGRFC...

LAT...LON   33659502 33329466 32629484 31869568 31279674 
            31059761 31109812 31429858 31729835 32139771 
            32549719 32769670 33069627 33319596 33569559