MESOSCALE PRECIPITATION DISCUSSION 0706
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
455 PM EST SAT DEC 26 2015
 
AREAS AFFECTED...E OKLAHOMA...N TEXAS...NW ARKANSAS...EXT SW MO 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 262155Z - 270355Z
 
SUMMARY...SLOW EASTWARD PUSH OF COLD FRONT WITH TRAINING
BACKBUILDING CONVECTION WITH OCCASIONAL MERGERS WITH WARM SECTOR
STRONG CELLS LIKELY TO LEAD TO FLASH FLOODING CONDITIONS. 

DISCUSSION...SATL LOOP SHOWS STRENGTHENING UPPER LOW OVER S NM/N
CHIHUAHUA WITH S/W RIDGING/BAROCLINIC LEAF LIFTING INTO KS WITH
SIGNIFICANT HEIGHT FALLS ACROSS MUCH OF TX AND SOUTHERN HIGH
PLAINS.  STRENGTHENING COLD SURGE BEHIND WELL DEFINED SURFACE COLD
FRONT SHOULD REDUCE ANAFRONTAL SHOWERS AND CONVECTION AND FOCUS
DEEPER COLD TOPPED CBS ALONG THE FRONT FROM CURRENTLY FROM RPH TO
PVJ TO SNL...NEARING THE TRIPLE POINT WITH WARM FRONT THAT EXTENDS
E ACROSS E CENTRAL OK JUST SOUTH OF  THE BOSTON MTNS/OZARK PLATEAU
ATTM.  THE WARM SECTOR IS DEFINED BY MID 70S TEMPS WITH TDS IN THE
UPPER 60S TO LOW 70S...TO SUPPORT MODERATE SB INSTABILITIES TO
1750 J/KG...WITH PROFILES NEARLY SATURATED WITH RECORD OR NEAR
RECORD TPW VALUES NEAR OR OVER 1.5" BEING ADVECTED NORTH ON
50-60KT SSWLY LLJ.  THIS WILL SUPPORT HIGHLY EFFICIENT RAINFALL
PRODUCTION WITH INCREASED MST FLUXES LEADING TO CONVECTION CAPABLE
OF 1.25-1.5"/HR AT TIMES.

CELLS WILL GENERALLY MOVE RAPIDLY NNE WITH CONTINUED UPSTREAM
REDEVELOPMENT.  THOUGH COLD SURGE IS STRENGTHENING...IT IS MAINLY
FOCUSED SOUTH ALLOWING FOR VERY SLOW FORWARD PROGRESS OF THE COLD
FRONT.  THESE FACTORS THIS SHOULD ALLOW FOR A TRAINING ENVIRONMENT
PARTICUARLY FURTHER NORTH INTO OK WHERE OVERALL CONVECTIVE
COVERAGE WILL BE MORE NUMEROUS NEAR THE TRIPLE POINT. 

ADDITIONALLY...PRE-COLD FRONTAL WARM SECTOR CONVECTION HAS ALSO
BROKEN OUT ACROSS N TX INTO SE OK...THOUGH THREAT IS MAINLY
SVR...THESE CELLS ARE CAPABLE OF HIGH BURSTS OF RAIN TO SET THE
STAGE IN RIVERS AND STREAMS PRIOR TO THE COLD FRONTAL PUSH
EASTWARD. THESE CELLS WILL ALSO LIFT NORTHWARD AND BEGIN TO
ELEVATE OVER THE FRONTAL BOUNDARY AND MERGE WITH ONGOING
SHOWERS/CONVECTION DEVELOPING IN THE TROWAL.  THIS WILL COMPOUND
TOTALS AND LEAD TO AN SW TO NE CORRIDOR OF INCREASED TOTALS NEAR
SEMINOLE/OKMULGEE/MCINTOSH TO CHEROKEE COUNTIES.. WITH 6HR TOTALS
AROUND 3-5"...NEAREST THE TRIPLE POINT AS IT SHIFTS EAST/ENE.
WV/IR LOOP SHOWS THE ENHANCED TOPS OF CONVECTION NEAR THE TRIPLE
POINT ALSO TAKING ON A TYPICAL WEDGE SHAPE APPEARANCE AT THE APEX
OF INCREASINGLY DIFFLUENT UPPER LEVEL FLOW WHICH ALSO SUPPORTS
OVERALL INCREASED UVVS. 

OVERALL MODEL GUIDANCE HAS BEEN VERY CONSITENT WITH LOCATION AND
MAGNITUDE OF THESE HIGH TOTALS SO CONFIDENCE IS FAIRLY HIGH IN A
LARGER FLASH FLOODING SITUATION DEVELOPING OVER THE NEXT FEW
HOURS. RECENT HI-RES CAMS PARTICULARLY THE 12Z ARW ALONG WITH LAST
FEW RUNS OF THE ESRL EXPERIMENTAL HRRR AS WELL AS THE OPERATIONAL
HRRR 

GALLINA

ATTN...WFO...FWD...LZK...OUN...SGF...SHV...TSA...

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

LAT...LON   37369400 37109275 36449263 35979317 35309416 
            34379498 33649576 33069637 32739763 33109839 
            33899833 35239741 36309628 36889515