936 FXUS64 KMAF 222342 AFDMAF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX 642 PM CDT WED MAY 22 2013 .DISCUSSION... SEE AVIATION DISCUSSION BELOW. && .AVIATION... LOW LEVEL JET WILL HELP TO KEEP WINDS UP OVERNIGHT AT MOST SITES. LOW LEVEL MSTR WILL RETURN OVERNIGHT ALSO BUT HAVEN/T SEEN ANY INDICATIONS OF LOW CLOUDS. SATELLITE DOES SHOW HIGH CLOUDS INCREASING FROM THE W AND BKN200-250 WILL PREVAIL TONIGHT. THE CHANCE OF SHRA/TSRA WILL INCREASE AFTER 18Z THUR. FOR NOW HAVE OPTED LEAVE PROB30 GROUPS OUT BUT THEY WILL PROBABLY BEGIN TO APPEAR IN TAFS IN THE 06Z AND 12Z ISSUANCES. && .PREV DISCUSSION... /ISSUED 237 PM CDT WED MAY 22 2013/ DISCUSSION... ZONAL FLOW WILL INHIBIT CONVECTION TODAY...BUT AN AMPLIFYING RIDGE OVER THE CENTRAL PLAINS WILL CAUSE FLOW TO BACK FROM THE SOUTHWEST IN THE LEE OF THE ROCKIES ALLOWING SHOWERS AND THUNDERSTORMS TO FORM THURSDAY AND CONTINUE INTO THE WEEKEND. THE BACKING FLOW WILL CAUSE LOW LEVEL MOISTURE TO SURGE WESTWARD INCREASING INSTABILITY ACROSS THE CWA HOWEVER WITH NO SURFACE BOUNDARY TO FOCUS ON...THUNDERSTORMS WILL BE WIDELY SCATTERED WITH DAYTIME HEATING AND WEAK UPPER DISTURBANCES BEING THE MAIN TRIGGERS. THE ONE FACTOR THAT IS IMPOSSIBLE TO FORECAST FOR WILL BE OUTFLOW BOUNDARIES WHICH COULD PROVIDE WEAK LOW LEVEL CONVERGENCE. ONE SUCH FEATURE MAY PUSH SOUTH TOMORROW EVENING AS CONVECTION FIRES IN THE TEXAS PANHANDLE ALONG A STATIONARY FRONT. AS MENTIONED BY THE MID SHIFT...PRECIPITABLE WATER VALUES WILL INCREASE FROM ONE HALF INCH CURRENTLY TO WELL OVER AN INCH TOMORROW AND FRIDAY MEANING THERE WILL BE ENOUGH MOISTURE PRESENT FOR HEAVY RAIN. THE THREAT FOR VERY LOCALIZED FLOODING WILL BE PRESENT ESPECIALLY IN URBAN AREAS WHERE DRAINAGE IS POOR. THE OVERALL SEVERE WEATHER THREAT HOWEVER WILL BE LOW AS 0-6KM SHEAR VALUES JUST ARE NOT QUITE HIGH ENOUGH. THE INCREASE IN PRECIP AND CLOUDS WILL BRING HIGH TEMPS BACK DOWN BELOW CLIMO AND MAKE FOR A PLEASANT NEXT FEW DAYS. MID LEVEL WINDS BECOME SLIGHTLY MORE WESTERLY BY SUNDAY SO DECIDED TO END POPS AT THAT TIME THOUGH THE GENERAL WEST COAST TROUGH/CENTRAL PLAINS RIDGE REGIME WILL CONTINUE SO CANNOT RULE OUT RAIN CHANCES INTO NEXT WEEK. IN FACT SEVERAL MODELS DO SHOW RAIN NEXT WEEK BUT WILL NOT INTRODUCE POPS THAT FAR OUT GIVEN HOW DRY WE HAVE BEEN RECENTLY. HENNIG && .MAF WATCHES/WARNINGS/ADVISORIES... NM...NONE. TX...NONE. && $$