000 
FXUS64 KMAF 191118
AFDMAF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX
518 AM CST TUE FEB 19 2008

.AVIATION...
LIGHT AN VARIABLE WINDS WILL PICK UP TODAY FROM THE SOUTHEAST TO
NEAR 10KT...THEN DROP BACK TO NEAR CALM AGAIN OVERNIGHT TONIGHT.
HIGH CLOUDS WILL CONTINUE TO STREAM IN FROM THE WEST AND REMAIN
BKN250 FOR MOST OF THE DAY BEFORE BREAKING OUT TO FEW-SCT250
OVERNIGHT. VFR CONDITIONS ARE EXPECTED FOR THE NEXT 24 HOURS. /13/

&&

.PREV DISCUSSION... /ISSUED 435 AM CST TUE FEB 19 2008/ 

DISCUSSION...
BEAUTIFUL...IF A LITTLE WARM...WEATHER IN TAP THROUGH TOMORROW
DUE TO ZONAL UPPER FLOW WITH WEAK SOME RIDGING. THE MAIN FORECAST
PROBLEM THIS FORECAST PERIOD IS THE PROGRESSION OF COLD AIR DUE
LATER THIS WEEK.

THE NAM AND ECMWF ARE THE MOST PROGRESSIVE WITH THE COLD FRONT
SENDING IT INTO THE AREA AS EARLY AS WEDNESDAY NIGHT. THE GFS
BRINGS THE FRONT TO THE DOORSTEP OF THE PERMIAN BASIN...PERHAPS
EVEN BRINGS IT INTO THE NORTHEASTERN CWA...BUT HOLDS OFF BRINGING
IT THROUGH MOST OF THE AREA UNTIL FRIDAY. A COUPLE OF FACTORS HAD
ME LEAN THE FORECAST TOWARDS THE GFS SOLUTION. FIRST THE SHORT
WAVE TROUGH THAT INITIATES THE PUSH OF COLD AIR SOUTHWARD NEVER
PROGRESSES ANY FURTHER SOUTH THAN THE GREAT LAKES REGION SO THE
COLD AIR WILL HAVE NO UPPER SUPPORT. SLICING UNDER AN UPPER
RIDGE...THE COLD AIR WILL MAKE ONLY SO MUCH PROGRESSION BEFORE
STALLING AND WAITING FOR SUPPORT WHICH WILL ULTIMATELY COME IN THE
FORM OF A SHORTWAVE TRAVELLING ACROSS THE SOUTHERN ROCKIES
REACHING WEST TEXAS ON THURSDAY. I FEEL THE COLD AIR WILL PROGRESS
ABOUT AS FAR SOUTH AS THE CENTER OF THE UPPER LOW WHICH MOST
MODELS SHOW MOVING ACROSS LBB WHICH WOULD MEAN THE COLD AIR WOULD
HOLD TO OUR NORTH. ALSO THE LATEST RUN OF THE ECMWF...WHILE MORE
PROGRESSIVE ON THE SURFACE COLD AIR...IS SLOWER WITH THE UPPER LOW
COMING MORE IN LINE WITH THE GFS WITH THE TIMING OF THIS FEATURE.
SLOWER TIMING OF THE UPPER LOW IS PREFERRED SINCE IT WILL BE
MOVING INTO A SPLIT FLOW PATTERN ACROSS THE CENTRAL U.S. WHICH
WILL TAKE SOME SPEED OFF THE SOUTHERN STREAM JET AND SLOW AND
FEATURES TRAVELLING ALONG IT. SO WITH COLD AIR HOLDING TO THE
NORTH AND A SLOWER UPPER LOW LEANED TOWARD THE GFS AND BROUGHT THE
BULK OF THE COLD AIR INTO THE AREA THURSDAY NIGHT. THIS IS A
LITTLE FASTER THAN THE GFS WHICH WILL PROBABLY BE TOO SLOW GIVEN
IT DOES NOT HANDLE SHALLOW COLD AIR WELL. 

TEMPS GET KNOCKED BACK A BIT FRIDAY BUT TEMPS WILL REBOUND QUICKLY
AS AN UPPER LEVEL RIDGE BUILDS INTO THE AREA. THE JET BECOMES
ACTIVE BY THE WEEKEND WITH A SERIES OF UPPER LEVEL TROUGHS MOVING
THROUGH THE FLOW EACH SENDING A WEAK SHOT OF COLD AIR INTO THE
AREA...DOING LITTLE MORE THAN KEEPING TEMPS AROUND CLIMO.
UNFORTUNATELY STILL DO NOT SEE RAIN THROUGH THE FORECAST
PERIOD...THOUGH WILL HAVE TO KEEP AN EYE OUT FOR FRIDAY AS LOW
LEVEL MOISTURE IMMEDIATELY BEHIND THE FRONT MAY GET THE NECESSARY
LIFT FROM THE PASSING UPPER LOW TO GENERATE A FEW SHOWERS.

HENNIG

&&

.MAF WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.

&&

$$

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