National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS64 KLUB 212307
AFDLUB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
607 PM CDT TUE MAY 21 2013

.AVIATION...
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. LIGHT NORTH WINDS TO
BECOME SOUTHERLY THIS EVENING THEN INCREASE TOWARDS 15 KTS BY
MIDDAY WEDNESDAY.

&&

.PREV DISCUSSION... /ISSUED 404 PM CDT TUE MAY 21 2013/

SHORT TERM...
LARGE-SCALE ASCENT ASSOCIATED WITH A 60-70 KT ULJ ON THE SRN FLANK
OF A SHORTWAVE TROUGH MOVING ACROSS THE PANHANDLES IS MAINTAINING
SOME MODEST CONVECTION ACROSS THE SRN PANHANDLE AND ROLLING PLAINS
THIS MID-AFTERNOON. INSTABILITY IS VERY MEAGER...SBCAPES UNDER 200
J/KG...SO WE BARELY EXPECT THUNDER WITH THIS ACTIVITY. HOWEVER...A
MID-LVL COLD POCKET ROTATING SWD AROUND THE WRN FLANK OF THE TROUGH
IS INCREASING MID-LVL INSTABILITY ACROSS NE NM AND THE WRN
PANHANDLES WITH SBCAPES ANALYZED TO AROUND 500 J/KG. THIS AREA WILL
PROGRESS SEWD TOWARD THE FA LATE THIS AFTERNOON AND EVENING AND AS A
RESULT WE COULD SEE ANOTHER BATCH OF SHOWERS/TSTMS DEVELOP AND MOVE
SEWD TOWARD MAINLY OUR NRN ZONES. LIMITED MOISTURE SHOULD KEEP THE
ACTIVITY ISOLATED TO WIDELY SCATTERED. AN ISOLD STRONG STORM WITH
SMALL HAIL IS NOT OUT OF THE QUESTION UNTIL THE BOUNDARY LAYER
BEGINS TO STABILIZE AROUND SUNSET. SFC RIDGING WILL BRING LIGHT
WINDS OVERNIGHT WITH SEASONABLY COOL TEMPS. THEN FOR WEDNESDAY...A
RETURN TO SRLY WINDS AND AN UPPER RIDGE APPROACHING FROM THE WEST
SHOULD RESULT IN WARMER TEMPS...RIGHT AROUND 90F EXPECTED FOR MANY
LOCATIONS. SHALLOW MOISTURE WILL MIX OUT ACROSS THE CAPROCK.
MOISTURE WILL LIKELY BE SUFFICIENTLY DEEP TO GENERATE SOME POTENTIAL
INSTABILITY IN THE ROLLING PLAINS...BUT THE ATMOSPHERE IS EXPECTED
TO REMAIN CAPPED WITH BUILDING HEIGHTS ALOFT.

LONG TERM...
INITIALLY PROGRESSIVE FLOW REGIME WILL TREND MORE BLOCKY LATER
THIS WEEK IN RESPONSE TO LONGWAVE RIDGING EMERGING FROM THE
CENTRAL GREAT PLAINS ALL THE WAY NORTH TO THE OIL SANDS OF FORT
MCMURRAY, ALBERTA. FORTUNATELY...THE SOUTH PLAINS OF TEXAS WILL
FALL UNDER THE SUBTROPICAL JET RESIDING SOUTH OF THE REGION OF
STRONG HEIGHT RISES. THIS RIDGE WILL EDGE SLOWLY EASTWARD THROUGH
THE HOLIDAY WEEKEND SUBJECTING THE CWA TO SOUTHWEST UPPER FLOW
DOWNSTREAM OF A SEMI-STATIONARY TROUGH OVER THE WESTERN CONUS.
UPSHOT OF THIS IS AN INCREASINGLY ACTIVE PATTERN FOR OUR DOMAIN
BEGINNING THURSDAY BEFORE THE MEAN DRYLINE BECOMES SITUATED WEST
OF THE 100TH MERIDIAN THEREAFTER...ULTIMATELY GIVING OUR FRIENDS
IN OKLAHOMA A MUCH-NEEDED BREAK FROM THEIR RECENT RASH OF SEVERE
WEATHER.

BIGGEST FORECAST CHALLENGE FOR THE NEXT WEEK IS THIS THURSDAY AND
CONCERNS THE THREAT FOR SIGNIFICANT SEVERE CONVECTION. DESPITE THE
500MB RIDGE AXIS DIRECTLY OVER THE SOUTH PLAINS...THIS AREA IS
UNDER A RELATIVE WEAKNESS IN THE RIDGE AS THE SUBTROPICAL JET WILL
BE OVER THE REGION. AMPLE MOISTURE CURRENTLY IN CENTRAL TX WILL BE
CHANNELED WEST-NORTHWEST WED AFTERNOON AND OVERNIGHT LEADING TO
RICH PWATS BY THURSDAY AHEAD OF A DRYLINE AND CRUCIAL FRONTAL
BOUNDARY PROGGED TO BACKDOOR SLOWLY ACROSS THE TX PANHANDLE. HAVE
KEPT TIMING OF THIS FRONT ON TRACK WITH EARLIER FORECASTS FAVORING
STRONG LL CONVERGENCE OVER OUR N-NERN COUNTIES BY PEAK HEATING.
FORECAST SOUNDINGS ARE NOTHING SHORT OF IMPRESSIVE FOR ORGANIZED
SEVERE MODES INCLUDING SUPERCELLS. LOCATION OF THE FRONT WILL
PROVE CRITICAL FOR A TORNADIC THREAT AS 0-3KM HELICITIES NEAR THIS
BOUNDARY ARE SHOWN TO REACH IN EXCESS OF 300 M2/S2. DID ADD SEVERE
MENTION AND LOCALLY HEAVY RAIN LATE THURSDAY FOR THE NERN QUARTER
OF OUR CWA NEAR THIS BOUNDARY WHERE STRONG CAPE AND PWATS AOA ONE
INCH APPEAR LIKELY.

THEREAFTER...GULF MOISTURE WILL REMAIN INTACT OVER MUCH OF THE CWA
WITHIN SUSTAINED S-SELY 850MB FLOW. DAILY DRYLINE POSITION THROUGH
AT LEAST EARLY NEXT WEEK FAVORS THE NM STATE LINE AREA WITH
PERHAPS DAILY CHANCES FOR TSTORMS...BUT FOR NOW HAVE ENDED MENTION
AFTER SUNDAY NIGHT GIVEN THIS IS OVER FIVE DAYS OUT. HOWEVER...THE
UPPER FLOW DOES MAINTAIN A FAVORABLY UNSETTLED SWLY MID-LEVEL
FLOW THAT COULD CERTAINLY WARRANT DAILY DRYLINE STORMS. BARRING
CONVECTIVE DEBRIS...TEMPS LOOK TO HOLD WITHIN 5 DEGS OR SO OF
SEASONABLE AVERAGES THROUGH THE PERIOD.

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA        50  87  57  87  58 /  10   0  10  20  30
TULIA         53  88  59  87  61 /  10   0  10  30  30
PLAINVIEW     53  88  61  88  63 /  10   0  10  30  40
LEVELLAND     53  90  63  90  63 /   0   0  10  20  30
LUBBOCK       55  90  64  90  65 /  10   0  10  20  40
DENVER CITY   54  90  64  94  64 /   0   0  10  20  20
BROWNFIELD    54  92  65  91  64 /   0   0  10  20  20
CHILDRESS     55  90  63  89  64 /  10  10  10  50  50
SPUR          55  90  63  91  66 /   0  10  10  20  40
ASPERMONT     58  93  67  93  68 /  10  10  10  20  40

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

07