DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1137 PM CST SAT DEC 26 2015 VALID 271200Z - 281200Z ...THERE IS AN ENH RISK OF SVR TSTMS ACROSS PARTS OF EAST TX...SW AR AND NW LA... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN PLAINS...ARKLATEX AND LOWER MS VALLEY OUTSIDE OF THE ENHANCED RISK AREA... ...THERE IS A MRGL RISK OF SVR TSTMS ACROSS PARTS OF THE SRN PLAINS...OZARKS...MID MS VALLEY AND CNTRL GULF COAST STATES OUTSIDE OF THE SLIGHT RISK AREA... ...SUMMARY... SCATTERED STRONG TO SEVERE THUNDERSTORMS...SOME CAPABLE OF PRODUCING TORNADOES...DAMAGING WINDS...AND HAIL...WILL MOVE ACROSS EASTERN TEXAS...FAR SOUTHEAST OKLAHOMA...AND INTO PARTS OF ARKANSAS AND LOUISIANA FROM SUNDAY MORNING THROUGH SUNDAY EVENING...AND THEN ACROSS THE LOWER MISSISSIPPI VALLEY THROUGH EARLY MONDAY. ...SRN PLAINS/ARKLATEX/LOWER TO MID MS VALLEY... AN UPPER-LEVEL LOW WILL MOVE ACROSS THE RIO GRANDE VALLEY INTO THE WRN TX HILL COUNTRY ON SUNDAY AS A 70 TO 90 KT MID-LEVEL JET ROUNDS THE BASE OF THE SYSTEM. AT THE SFC...A COLD FRONT WILL MOVE EWD ACROSS EAST TX TODAY. THUNDERSTORMS SHOULD BE ONGOING ALONG THE FRONT AT THE START OF THE PERIOD. AS SFC TEMPS WARM EARLY IN THE DAY...THUNDERSTORM INTENSITY SHOULD GRADUALLY INCREASE AS A SQUALL-LINE ORGANIZES AND MOVES EWD ACROSS EAST TX. A MOIST WARM SECTOR WITH SFC DEWPOINTS NEAR 70 F ALONG WITH MODERATE INSTABILITY WILL BE FAVORABLE FOR STRONG UPDRAFTS WITH CELLS EMBEDDED IN THE SQUALL-LINE. MORE DISCRETE THUNDERSTORMS MAY ALSO DEVELOP AHEAD OF THE LINE FROM THE ARKLATEX SSWWD TO THE HOUSTON AREA DURING THE AFTERNOON. FORECAST SOUNDINGS FROM LUFKIN TO HOUSTON TOMORROW AT 21Z SHOW STRONG DEEP-LAYER SHEAR PROFILES FAVORABLE FOR SEVERE STORMS. 0-6 KM SHEAR IS ESTIMATED FROM 55 TO 60 KT. IN ADDITION...0-3 KM SHEAR IS FORECAST TO BE IN THE 350 TO 400 M2/S2 RANGE SUGGESTING THE ENVIRONMENT WILL BE FAVORABLE FOR TORNADOES. TORNADOES WILL BE POSSIBLE WITH ROTATING CELLS EMBEDDED IN THE LINE AND WITH THE MORE DISCRETE CELLS JUST AHEAD OF THE LINE. A STRONG TORNADO WILL BE POSSIBLE FROM THE HOUSTON AREA NWD TO NEAR LUFKIN TOMORROW AFTERNOON. ALSO...FORECAST SOUNDINGS SHOW STRONG SPEED SHEAR IN THE LOW-LEVELS WITH 50 KT OF FLOW AT 850 MB. AS THE SQUALL-LINE TRANSFERS THIS FLOW TOWARD THE SFC...WIND DAMAGE WILL BECOME LIKELY WITH THE STRONGER CELLS EMBEDDED IN THE LINE. AN ENHANCED WIND DAMAGE THREAT IS EXPECTED TO DEVELOP THIS AFTERNOON FROM THE ARKLATEX SWWD TO THE UPPER TX COASTAL PLAINS. HAIL MAY ALSO OCCUR IN AREAS THAT DESTABILIZE SUFFICIENTLY AHEAD OF THE LINE. THE SQUALL-LINE IS FORECAST TO MOVE EWD INTO THE LOWER MS VALLEY DURING THE EVENING AND OVERNIGHT PERIOD WHERE A WIND DAMAGE THREAT WILL BE POSSIBLE. THE WIND DAMAGE THREAT MAY EXTEND AS FAR NORTH AS NW MS AND ERN AR WHERE INSTABILITY WILL BE WEAK BUT SHEAR PROFILES WILL BE QUITE STRONG. ..BROYLES/ROGERS.. 12/27/2015Read more
from SPC Forecast Products http://ift.tt/s7Jkvo
No comments:
Post a Comment