MESOSCALE PRECIPITATION DISCUSSION 0120
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1247 AM EDT SUN APR 17 2016
 
AREAS AFFECTED...SW OKLAHOMA...N/CENT TEXAS 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 170500Z - 171100Z
 
SUMMARY...CONFLUENT CONVECTIVE LINES WILL MERGE AND INCREASE
RAINFALL EFFICIENCY WHILE SLOWLY PROGRESSING EAST PROVIDING HIGH
RATES TO CONTINUE FLASH FLOOD THREAT THROUGH 11-12Z. 

DISCUSSION...WV LOOP INDICATES S/W INFLECTION ACROSS TX PANHANDLE
WITH ASSOCIATED SSE TO NNW ORIENTED 90 KT UPPER LEVEL JET THAT IS
FORECAST TO ENHANCE TO 110 KTS PROVIDING RIGHT ENTRANCE ASCENT
OVER SW OK...COUPLED WITH DIFFLUENT FLOW AS FLOW SOUTH OF S/W TROF
IS FLATTER ACROSS CENTRAL TX.  IN THE LOWER LEVELS...DUAL MOISTURE
CHANNELS...A WEAK ONE ALONG THE PACIFIC FLOW THROUGH THE
CONVECTIVE COMPLEX ACROSS THE EDWARDS PLATEAU AND THE DEEPER
RETURN FLOW OFF THE GULF THROUGH GALVESTON BAY INTO N CENT TX
BECOMING INCREASINGLY CONFLUENT ACROSS THE W OK/TX RED RIVER
BORDER...WITH 40 KT LLJ FROM THE SE AT 850MB SUPPORTING VERY DEEP
MOISTURE CONVERGENCE SIGNAL.  DEEPEST MOISTURE WITH TPWS UP TO
1.5" WITHIN A NARROW CHANNEL ARE HIGHLIGHTED BY ACTIVE CONVECTION
OVER N CENTRAL TX AS THIS TIME...WHICH WILL PROVIDE AMPLE
OPPORTUNITIES FOR MERGERS AND LOCALIZED EXTREME SHORT TERM RATES
OF 3"+/HR.   THE COMBINATION OF THESE ELEMENTS IS PRESENTING DEEP
VIGOROUS UPDRAFTS WITH IR TOPS TO -75C ACROSS SE OK...AND WITH
DIFFLUENCE ALOFT HAS TAKEN A WEAK WEDGE APPEARANCE SUPPORTIVE OF
SW-NE CONVECTIVE DEVELOPMENT CAPABLE OF FURTHER REPEAT TRAINING.  

MANY HI-RES CAMS ARE VERY SUPPORTIVE OF THE IDEA OF VERY HIGH
TOTALS OVER THE NEXT 6HRS IN THE 4-6" RANGE AND GIVEN
ENVIRONMENTAL SETUP THIS DOES SEEM REASONABLE WITH SOME INCREASED
CONFIDENCE...AND EVEN THOUGH FFG VALUES ARE HIGHER...SSEO
NEIGHBORHOOD PROBABILITIES OF FFG EXCEEDANCE ARE IN THE 70-90
PERCENT RANGE MAKING FF LIKELY.


GALLINA

ATTN...WFO...FWD...LUB...OUN...SJT...

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

LAT...LON   35929899 35899818 35619786 35319785 33669791 
            32439802 32009847 32069983 32390039 32820035 
            33630043 34050047 34879958