MESOSCALE PRECIPITATION DISCUSSION 0625
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
628 PM EDT FRI OCT 30 2015
 
AREAS AFFECTED...CENTRAL AND NORTHERN TX...SOUTHERN OK 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 302221Z - 310130Z
 
SUMMARY...A NARROW BAND OF INTENSE SHOWERS AND THUNDERSTORMS
CONTINUES TO ADVANCE GRADUALLY EAST ACROSS PORTIONS OF NORTHERN TX
AND SOUTHERN OK. SOME LOCALIZED FLASH FLOODING IS POSSIBLE THROUGH
THE EARLY EVENING HOURS.

DISCUSSION...RADAR IMAGERY SHOWS A BAND OF INTENSE SHOWERS AND
THUNDERSTORMS MOVING EAST ACROSS PORTIONS OF CENTRAL AND NORTHERN
TX...FROM A LINE JUST SOUTHWEST OF BROWNWOOD NORTHEAST TO AN AREA
NORTHWEST OF MINERAL WELLS. A WEAKER EXTENSION OF THIS CONVECTIVE
BAND EXTENDS UP TO THE RED RIVER AND INTO FAR SOUTHERN OK.

THE CONVECTION IS ASSOCIATED WITH A WEAK SUBTROPICAL
SHORTWAVE/VORT CENTER THAT HAS EJECTED NORTHEAST INTO CENTRAL TX
OVER THE LAST FEW HOURS. THE ENERGY WITH THIS VORT IS INTERACTING
WITH A DEEP TROPICAL MOISTURE FEED...WITH DUAL FEEDS INVOLVING
BOTH THE EASTERN TROPICAL PACIFIC OCEAN AND THE GULF OF MEXICO.
AREA VWPS CONFIRM A SOUTHERLY LOW LEVEL JET OF 40 TO 50 KTS
INTERCEPTING THIS LINE OF CONVECTION. MEANWHILE...AS PER LATEST WV
IMAGERY...THE FLOW ON THE SYNOPTIC LEVEL IS QUITE DIFFLUENT OUT
AHEAD OF THE LARGER SCALE UPPER TROUGH EJECTING OUT INTO THE
SOUTHERN HIGH PLAINS.

THE LAST COUPLE RUNS OF THE HRRR SUGGEST THE CURRENT CONVECTIVE
BAND MOVING GRADUALLY EAST THE NEXT FEW HOURS...BUT WITH SOME
SLOWING OF ESPECIALLY THE SOUTHWEST EXTENSION OF THE LINE AS THE
MID LEVEL FLOW BACKS A BIT AHEAD OF THE AFOREMENTIONED UPPER
TROUGH APPROACHING THE REGION. THIS WILL FAVOR A SET-UP FOR
BACKBUILDING AND TRAINING CELLS THIS EVENING ACROSS PORTIONS OF
CENTRAL TX...AND WITH PWATS RUNNING AS HIGH AS 1.75 INCHES OVER
THIS REGION...LOCALLY VERY HEAVY RAINFALL TOTALS ARE EXPECTED
WHICH WILL BE IN ADDITION TO EARLIER RAINS.

SHORT-TERM RAINFALL RATES OF OVER 2 INCHES/HR CAN BE
EXPECTED...BUT ADDITIONAL STORM TOTALS OF 3 TO 4 INCHES WITH
ISOLATED HEAVIER AMOUNTS WILL BE POSSIBLE WHERE BACKBUILDING AND
TRAINING CELLS OCCUR. THUS...THIS WILL ENHANCE THE RISK FOR
ADDITIONAL FLASH FLOODING AT LEAST THROUGH THE EARLY EVENING HOURS.

ORRISON

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

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

LAT...LON   34719697 34419606 32699687 31069847 30839940 
            31179974 32249885 33489815