337  
FXUS64 KLUB 192041  
AFDLUB  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LUBBOCK TX  
341 PM CDT SAT APR 19 2014  
   
SHORT TERM
 
 
WV IMAGERY SHOWS OUR UPPER LOW OF INTEREST CONTINUING TO SLOWLY MOVE  
EASTWARD WHILE CONTINUING TO DRAW IN TROPICAL MOISTURE FROM THE  
PACIFIC. A SHORTWAVE PUSHING NORTH AND EASTWARD IS ALSO VISIBLE ON  
WV AND HAS BECOME MORE PRONOUNCED OVER THE PAST SEVERAL HOURS. THE  
SHORTWAVE STRETCHES FROM SOUTHERN NM THROUGH THE PERMIAN BASIN TO  
THE EDWARDS PLATEAU AND IS AIDING IN THE NUMEROUS SHOWER ACTIVITY IN  
SOUTHEAST NM AND ALONG THE TX/NM STATE LINE. SHOWERS HAVE BEEN SLOW  
TO MOVE EASTWARD IN PART DUE TO DRY AIR IN THE MID LEVELS. MUCH OF  
THE RAIN THAT HAS FALLEN HAS BEEN MOSTLY VIRGA WITH SOME LIGHT RAIN  
MAKING ITS WAY TO THE GROUND. LOOKING AT TRENDS FROM RAP ANALYSIS  
TOP DOWN MOISTENING IS HAPPENING BUT NOT IN AN EXTREME HURRY. WE  
SHOULD BE ABLE TO MOISTEN UP ENOUGH FOR WHEN THE SHORTWAVE MOVES  
OVERHEAD LATER THIS AFTERNOON INTO THE EVENING WHICH SHOULD PROVIDE  
NUMEROUS SHOWERS. I HAVE INCREASED POPS TO AROUND 60 FOR THE WESTERN  
HALF OF THE FA BUT HAVE CHANGED THE WX CATEGORY TO RAIN SHOWERS WITH  
A MENTION OF ISO THUNDER AS LAPSE RATES WILL BE SLOW TO STEEPEN AS  
THE CENTER OF THE LOW WILL STILL BE WELL TO OUR WEST. THIS ALONG  
WITH CLOUDY SKIES FOR A MAJORITY OF THE DAY HAVE LIMITED DAYTIME  
HEATING AND HAVE KEPT TEMPS ON THE COOL SIDE.  
 
RAIN SHOWERS AND THUNDERSTORMS WILL PERSIST THROUGH THE LATE EVENING  
AND ACTIVITY SHOULD TAPER DOWN AFTER MIDNIGHT WHEN THE SHORTWAVE HAS  
PASSED TO THE NORTH. THE NEXT FOCUS WILL BE TOMORROW AFTERNOON AND  
EVENING AS THE UPPER LEVEL LOW OPENS AND THE TROF MOVES INTO THE  
AREA. MODELS HAVE DIFFERED SLIGHTLY ON HOW TO HANDLE IT BUT AGREE IN  
DRYLINE CONVECTION FIRING LATE TOMORROW AFTERNOON. THE MAIN  
DIFFERENCE IN MODELS IS HOW FAR WEST WILL THE DRYLINE BEGIN TO  
CONVECT. THE NAM/TTU WRF SHOW THE DRYLINE CONVECTING IN THE  
SOUTHWESTERN TX PANHANDLE AND PUSHES SOUTHEASTWARD WHILE THE GFS  
FIRES CONVECTION NEAR THE EDGE OF THE CAPROCK AND PUSHES EASTWARD.  
FOR NOW I HAVE CONTINUED TO OPT FOR A BIT FARTHER WEST AS LOW LEVEL  
MOISTURE WILL STILL BE AVAILABLE AND THIS SCENARIO HAS BEEN MORE  
CONSISTENT WITH THE NAM/TTU WRF. CONCERNING SEVERE POTENTIAL...MID  
LEVEL LAPS RATES WILL STEEPEN AS THE TROF AXIS MOVES OVERHEAD WHICH  
WILL INCREASE OVERALL CAPE...BUT THE AMOUNT OF SBCAPE IS IN QUESTION  
AS THE SUN WILL STRUGGLE TO PEAK THROUGH THE CLOUDS TOMORROW. THERE  
MAY BE A WINDOW OF OPPORTUNITY TOMORROW FOR THE SUN TO SHINE THROUGH  
HELPING TO WARM SURFACE TEMPS. MUCAPE AROUND 1000 J/KG WILL BE  
ENOUGH TO TRIGGER STRONG CONVECTION ALONG THE DRYLINE. 0-6KM SHEAR  
AROUND 35 TO 45 KTS WITH MARGINAL DRY AIR ALOFT WILL HELP AID IN  
HAIL GROWTH PRODUCING LOW END SEVERE HAIL. SOME STRONG WINDS  
REACHING SEVERE CRITERIA WILL BE POSSIBLE AS WELL...HOWEVER  
WIDESPREAD SEVERE THUNDERSTORMS ARE NOT ANTICIPATED ATM AND WILL BE  
ISOLATED IN NATURE. ALDRICH  
 

 
   
LONG TERM
 
 
THE SLOW-MOVING UPPER TROUGH WILL BE SLOWLY EXITING THE AREA  
SUNDAY EVENING. INDICATIONS ARE THAT THE ATMOSPHERE WILL BE FAIRLY  
WORKED OVER BY EVENING AND WITH DECREASING SFC-BASED  
INSTABILITY...ANY SEVERE THREAT SHOULD DIMINISH AFTER 8 PM OR SO.  
SHOWERS MAY CONTINUE ACROSS THE EASTERN AREAS INTO THE NIGHT  
THOUGH...GRADUALLY DECREASING IN COVERAGE AND STRENGTH FROM WEST  
TO EAST. NW FLOW IN THE WAKE OF THE TROUGH WILL OPEN THE DOOR FOR  
A WEAK FRONT TO MOVE SOUTH ACROSS THE AREA MONDAY. THERE IS SOME  
SUGGESTION OF SOME LIGHT SHOWERS ACROSS OUR ERN ZONES AND ALSO  
PERHAPS IN THE NW...BUT WE/VE KEPT POPS BELOW MENTION FOR NOW. NOT  
MUCH CHANGE IN THE FORECAST BEYOND MONDAY. SHORTWAVE RIDGING ON  
TUESDAY SHOULD BRING WARMER TEMPS WHILE WINDS WILL RETURN TO A SERLY  
FETCH. FAIRLY DEEP TROUGH MOVING INTO THE ROCKIES SHOULD INDUCE A  
NICE LLJ TUESDAY NIGHT...AND BEGIN TO ADVECT GULF MOISTURE BACK  
INTO WTX. THE GFS STILL IS PRETTY BULLISH WITH THE MOISTURE RETURN  
ALL THE WAY TO THE STATE LINE OVERNIGHT AND COULD LIKELY RESULT IN  
SOME MORNING LOW STRATUS ACROSS THE CWA WEDNESDAY. THE LATEST GFS  
AND ECMWF REMAIN IN PRETTY GOOD AGREEMENT THAT A DRYLINE WILL FORM  
SOMEWHERE ACROSS THE EASTERN HALF OF THE CWA AND BOTH CONTINUE TO  
SHOW A GOOD QPF SIGNAL TO THE EAST OF THE DRYLINE WED AFTERNOON  
AND EVENING. THERE IS A BIT OF A CONCERN WITH THE STRENGTH OF THE  
CAP OVER THE DRYLINE...GUIDANCE IS CURRENTLY PROGGING TEMPS ONLY  
IN THE LOWER/MIDDLE 80S WHICH MAY NOT BE SUFFICIENT TO BREAK THIS  
CAP. WE ARE FORECASTING SOMEWHAT WARMER TEMPS BASED ON THE  
PATTERN...AND WE HAVE KEPT A SLIGHT CHANCE OF TSTMS EAST OF THE  
DRYLINE. DRIER AIR SHOULD SPREAD ACROSS THE AREA ON THURSDAY WITH  
ANOTHER WEAK FROPA LIKELY LATE THURSDAY OR FRIDAY. QUITE A BIT OF  
UNCERTAINTY IN THE FORECAST HEADING INTO NEXT WEEKEND. ANOTHER  
FAIRLY DEEP TROUGH WILL FORM UP ACROSS THE WEST...BUT MODELS  
DIVERGE WITH THE ECMWF SHOWING VEERED BROAD CYCLONIC FLOW OVER WTX  
SHUNTING DEEP MOISTURE TO THE EAST...WHILE THE GFS SHOWS LESS OF A  
WESTERLY COMPONENT AND A BETTER CHANCE OF MOISTURE HOLDING IN AND  
POSSIBLY LEADING TO SOME PRECIP POTENTIAL. WE/LL KEEP THE DRY FCST  
RUNNING WHILE FOLLOWING THE TRENDS.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
FRIONA 50 74 49 77 49 / 60 20 10 10 0  
TULIA 54 75 52 78 51 / 30 30 20 10 0  
PLAINVIEW 54 75 54 80 52 / 40 30 20 10 0  
LEVELLAND 54 76 54 80 52 / 60 20 10 10 0  
LUBBOCK 57 77 55 81 53 / 60 30 20 10 0  
DENVER CITY 55 78 55 79 53 / 60 20 10 10 0  
BROWNFIELD 56 78 54 80 53 / 60 20 10 10 0  
CHILDRESS 58 80 58 82 55 / 30 40 30 10 10  
SPUR 57 79 59 84 55 / 30 40 20 10 0  
ASPERMONT 58 79 60 85 56 / 30 40 30 10 0  
 

 
   
LUB WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
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