Area Forecast Discussion
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44
000
FXUS64 KLUB 261730
AFDLUB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
1230 PM CDT TUE APR 26 2016

.AVIATION...
VFR EXPECTED TO PERSIST NEXT 24 HOURS. WINDY CONDITIONS ARE
EXPECTED TO RAMP UP BY 19-20Z WITH QUITE TURBULENT LOW LEVEL CONDITIONS
PERSISTING THROUGH SUNSET. VIRGA SHOWERS COULD APPROACH KLBB/KPVW
TERMINALS LATER THIS AFTERNOON POSING A LOCAL DOWNBURST THREAT.
PILOTS ARE ADVISED TO REMAIN WELL CLEAR OF ANY VIRGA ACTIVITY.

&&

PREV DISCUSSION... /ISSUED 409 AM CDT TUE APR 26 2016/

SHORT TERM...
00Z UPPER AIR ANALYSIS SHOWED A CLOSED LOW OVER NEVADA/UTAH AT
500 HPA WITH A STRONG 110-120 KNOT JET DIVING SOUTH ON THE WEST
SIDE OF THE LOW. WATER VAPOR SATELLITE IMAGERY SHOWS THAT THE LOW
CONTINUES TO MAKE GOOD PROGRESS TO THE EAST THIS MORNING AND
COMPARING MODEL POSITIONS WITH INITIALIZATION TIME AND 06Z
LOCATION SHOWS THAT MODELS ARE A BIT FURTHER EAST THAN REALITY AS
OF 08Z. CLOSER TO THE SURFACE...GOOD MOISTURE PLUME AT 850 HPA IS
JUST TO THE EAST OF THE FORECAST AREA ACROSS NORTH TEXAS INTO
OKLAHOMA WITH DRY SOUTHWESTERLY FLOW OVER OUR AREA. SURFACE
ANALYSIS OVER THE PAST SEVERAL HOURS SHOW THAT THE DRYLINE HAS
MIXED ABOUT AS FAR WEST AS IT WILL EARLY THIS MORNING AND MAY BE
STARTING TO MIX BACK EAST. WEST TEXAS MESONET OBSERVATION AT REESE
WAS UP TO A 45 DEGREE DEWPOINT AT 07Z AND HAD DECREASED BACK TO 39
AT 08Z. WHETHER OR NOT THIS IS THE START OF THE DRYLINE MIXING
EAST REMAINS A BIT UNCERTAIN AS WIND SPEEDS PICKED UP OUT OF THE
SOUTHWEST BETWEEN OBSERVATIONS WHICH COULD HAVE INCREASED MIXING
IN THE LOCAL AREA. FURTHER TO THE EAST...DEWPOINTS CONTINUE TO
CLIMB ACROSS THE ROLLING PLAINS AND WE COULD POSSIBLY SEE SOME LOW
60 DEWPOINTS BY SUNRISE IN STONEWALL AND KENT COUNTIES.

REGARDLESS...THE APPROACHING CLOSED LOW WILL START TO INCREASE DEEP
MIXING AND DRY AIR ADVECTION OVER THE AREA BY SUNRISE WITH THE
DRYLINE RAPIDLY MIXING EAST INTO THE ROLLING PLAINS OR WESTERN NORTH
TEXAS BY 1 PM.  AT THE SAME TIME...WIND SPEEDS WILL BE ON THE
INCREASE AS THE SURFACE PRESSURE GRADIENT TIGHTENS ACROSS THE REGION
THANKS TO A DEEPENING SURFACE LOW OVER SOUTHERN KANSAS INTO THE
OKLAHOMA PANHANDLE.  MODELS CONTINUE TO BOUNCE AROUND BETWEEN 25 TO
35 KNOTS FOR WIND SPEEDS THIS AFTERNOON OUT OF THE WEST AND THE WAY
THE HEIGHT FIELDS ALOFT AND SURFACE PRESSURE GRADIENTS LOOK INDICATE
THAT THE HIGHER END OF GUIDANCE WILL BE POSSIBLE.  SUSTAINED WIND
SPEEDS OF 35 TO 40 MPH WILL DEVELOP ACROSS THE FORECAST AREA THIS
AFTERNOON AND GUSTS COULD APPROACH 50 MPH AT TIMES LATE THIS
AFTERNOON WHEN DAYTIME MIXING IS AT THE PEAK AND THE INCREASED
BOUNDARY LAYER DEPTH TAPS INTO 35 TO 45 KNOT WINDS AT THE 600 HPA
LEVEL.  CONFIDENCE IS HIGH ENOUGH THAT WE WILL ISSUE A WIND ADVISORY
FOR THIS AFTERNOON AND EARLY EVENING AND HAVE ALSO ADDED AREAS OF
BLOWING DUST FOR THE CAPROCK AS A PRETTY MUCH DUE WEST WIND TAPS
INTO FAVORED AREAS OF DUST GENERATION.  ONLY POSITIVE ITEM IN THE
FORECAST TODAY IS HIGH TEMPERATURES WILL BE A FEW DEGREES COOLER
THAN YESTERDAY AS HEIGHTS FALL WITH THE APPROACHING UPPER-LEVEL LOW.
THIS MAY LIMIT THE FIRE DANGER SOMEWHAT...SEE THE FIRE WEATHER
SECTION FOR MORE DETAILS.

WIND SPEEDS WILL DECREASE FAIRLY FAST AFTER SUNSET BUT WILL STILL BE
GUSTY AT TIMES THROUGH MIDNIGHT.  DUST WILL TAKE A BIT TO SETTLE BUT
EXPECT THAT 15 TO 25 MPH WINDS WILL BE PREVALENT AFTER MIDNIGHT
ACROSS THE AREA.  LOWS WILL BE FAIRLY MILD ONCE AGAIN AS WEST WIND
PROVIDES SOME DOWNSLOPE WARMING AND ALSO PREVENTS RADIATIONAL
COOLING FROM GETTING TOO MUCH OF A GRASP.

JORDAN

LONG TERM...
CONFIDENCE IS HIGH THAT AN UNSETTLED PATTERN WILL UNFOLD OVER
THE SOUTHERN HIGH PLAINS FROM LATE THIS WEEK THROUGH EARLY NEXT WEEK.
ON THE HEELS OF TODAY/S VIGOROUS UPPER CYCLONE...YET ANOTHER ROBUST
TROUGH WILL SET ITS SIGHTS ON THE SWRN CONUS BY LATE WEDNESDAY
COURTESY OF A SPLIT FLOW REGIME PRESENTLY OFFSHORE OF BRITISH
COLUMBIA. WEDNESDAY LOOKS LARGELY UNEVENTFUL LOCALLY BEHIND A
PACIFIC FROPA IN THE MORNING AND A MODIFIED CP INTRUSION BY WED
NIGHT. WILL GIVE THE NOD TO THE GLOBAL MODELS AND SREF MEAN WITH
THE HANDLING OF THIS LATTER FRONT GIVEN THEIR OVERALL BETTER TRACK
RECORD OF THESE BOUNDARIES WHEN COMPARED TO THE NAM. THESE MODEL
SOLUTIONS FAVOR THE FRONT STALLING SOMEWHERE OVER OUR DOMAIN BY
EARLY THURSDAY IN RESPONSE TO PRESSURE FALLS WEST OF THE AREA
AHEAD OF THE NEXT UA TROUGH.

ALTHOUGH SOME SIZABLE SURFACE MOISTURE DEFICITS ARE EXPECTED ON
THURSDAY FOLLOWING THE EARLIER FRONTS...AMPLE GULF MOISTURE IS
PROGGED TO BE LOOMING NOT TOO FAR SOUTHEAST OF THE REGION. STOUT
ISENTROPIC ASCENT WITH PWATS APPROACHING ONE INCH SHOULD BEGIN
LATE THU AFTN OVER THE S-SERN PART OF THE CWA AND ONLY AMPLIFY
N-NWWD THEREAFTER AS A SELY LLJ RAMPS UP. APPROACH OF THE
STRONGEST DCVA LATE THU NIGHT FAVORS THE BEST POPS AREA WIDE
BEFORE DEEP SUBSIDENCE AND DRY SLOTTING SWEEP NEWD THROUGH THE DAY
ON FRIDAY. AREAS POLEWARD OF THE INTERSECTION OF THE LLJ AXIS AND
WARM FRONT COULD COME AWAY WITH SOME IMPRESSIVE RAIN AMOUNTS
ESPECIALLY IF TRAINING CELLS EMERGE. SEVERE-WISE...THIS ELEVATED
CAPE AND FAVORABLE SHEAR REGIME IS MORE THAN ADEQUATE FOR SOME
HAILERS WHICH IS ADDRESSED IN SPC/S SWODY3 SLIGHT RISK AND
SUPPORTED WELL IN THE CIPS ANALOGS. POPS WERE DRIED OUT
AGGRESSIVELY FROM W-E ON FRIDAY WHILE RETAINING SOME AFTERNOON
MENTION IN OUR FAR NERN ZONES NEAREST THE DRYLINE.

DRYLINE SHOULD EXIT THE REGION FRI EVENING AS THE UPPER LOW EJECTS
OUT OF NERN NM. THEREAFTER...THE LOW IS FAVORED TO BECOME STACKED
AND STALL IN NERN CO WHILE GRADUALLY RE-MOISTENING OUR DRY
CYCLONIC FLOW THROUGH THE WEEKEND. RATE AT WHICH THIS OCCURS IS
NOT CLEAR...BUT BY SUNDAY AND ESPECIALLY MONDAY A KICKER IMPULSE
LOOKS TO GIVE THE STALLED LOW NEW LIFE WHILE DIRECTING DEEPER LIFT
AND SATURATION OUR WAY. ARRIVAL OF UNSEASONABLY COOL AIR WITH ONE
OR TWO FRONTS DURING THIS TIME SHOULD FOCUS PRECIP CHANCES...SO
HAVE LEFT THE BROAD SMEARING OF SUPERBLEND POPS INTACT. LASTLY...THE
MOS CLIMO CURVE IS CLEARLY SKEWING THIS OBVIOUSLY CLOUDY/COOL/SHOWERY
PATTERN FROM SUN-MON...SO HAVE UNDERCUT MOS HIGHS CONSIDERABLY.

FIRE WEATHER...
PATTERN FOR TODAY IS VERY CLOSE TO THE SOUTH PLAINS FIRE OUTBREAK
CONDITIONS WITH ONE MAJOR EXCEPTION...AND THAT IS THE GREENNESS OF
AREA FUELS AND BELOW OR NEAR NORMAL ENERGY RELEASE COMPONENT IN
FUELS.  STRONG WINDS AND MINIMUM RH VALUES IN THE UPPER SINGLE
DIGITS TO LOW TEENS BOTH ARE MAJOR RISK FACTORS FOR WILDFIRE
DEVELOPMENT BUT THE UNCERTAINTY AROUND THE FUEL COMPONENT WILL
PRECLUDE ISSUING A RED FLAG WARNING FOR TODAY.  WILL START OFF THE
DAY WITH A FIRE DANGER STATEMENT FOR BOTH THE SOUTH PLAINS AND
ROLLING PLAINS BUT WILL ALSO HIGHLIGHT THAT CONDITIONS COULD WARRANT
AN UPGRADE TO A RED FLAG WARNING IF WE START TO SEE SEVERAL FIRE
STARTS ACROSS THE AREA.  THE SOUTH PLAINS WILL HAVE THE GREATEST
CHANCE OF SEEING RED FLAG CONDITIONS DEVELOP AS MINIMUM RH VALUES
WILL BE THE LOWEST AND WIND SPEEDS THE HIGHEST THIS AFTERNOON...
ESPECIALLY FOR AREAS WEST OF INTERSTATE 27/HIGHWAY 87.

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR TXZ021>044.

&&

$$

99/99/26



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.