000 FXUS64 KMEG 260946 AFDMEG AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MEMPHIS TN 446 AM CDT SUN OCT 26 2008 .DISCUSSION... FREEZE/FROST POTENTIAL MONDAY NIGHT INTO TUESDAY MORNING AS WELL AS TUESDAY NIGHT INTO WEDNESDAY REMAINS THE BIGGEST FORECAST CHALLENGE. LATEST MODELS WERE IN GOOD AGREEMENT OVER THE NEXT 7 DAYS. USED A BLEND OF ALL OF THEM. GENERALLY PREFERRED THE COOLER GUIDANCE NUMBERS FOR TEMPERATURES MONDAY THROUGH WEDNESDAY. THE BIGGEST CHANGE FROM THE PREVIOUS FORECAST IS TO ISSUE A FREEZE WATCH FOR AREAS NORTH OF A FORREST CITY ARKANSAS TO MEMPHIS TO SAVANNAH TENNESEE LINE LATE MONDAY NIGHT THROUGH TUESDAY MORNING. ALSO...LOWERED TEMPERATURES SLIGHTLY MONDAY THROUGH WEDNESDAY NIGHT. AT 430 AM CDT ACROSS THE MIDSOUTH AND FORECAST AREA...CLEAR AND COOL CONDITIONS WERE OCCURRING WITH SURFACE TEMPERATURES RANGING FROM 36 AT SAVANNAH TN TO 54 AT MARIANNA AR. HIGH PRESSURE WAS OVER SOUTHERN MISSISSIPPI WHILE A COLD FRONT EXTENDED FROM CENTRAL KANSAS TO LAKE MICHIGAN. TODAY WILL BE MOSTLY SUNNY AND WARMER DAY WITH INCREASING WEST TO SOUTHWEST WINDS AHEAD OF THE APPROACHING COLD FRONT MENTIONED ABOVE. THINK WARM AIR ADVECTION AND ABUNDANT SUN WILL BOOST HIGH TEMPERATURES INTO THE LOWER AND MID 70S. TONIGHT...A STRONG COLD FRONT WILL QUICKLY MOVE THROUGH DURING THE EVENING HOURS...BRINGING GUSTY NORTH WINDS AND COLDER AIR. WITH MOISTURE LACKING ALONG THE FRONT...DO NOT EXPECT ANY RAIN AND ONLY A FEW CLOUDS WITH THE FRONT. THINK MORNING LOWS WILL RANGE FROM THE MID 30S OVER THE MO BOOTHEEL TO LOWER 40S ACROSS NORTH MS. MONDAY WILL BE MUCH COLDER AND MOSTLY SUNNY OVER THE AREA. NORTH WINDS 10 TO 20 MPH WILL NOT ALLOW FOR MUCH WARMING. WENT BELOW MODEL GUIDANCE FOR HIGHS...IN THE 50S EVERYWHERE WITH COOLEST READINGS OVER NW TN WHERE SOME CUMULUS DEVELOPMENT WILL PROBABLY OCCUR AS 850 MB TEMPERATURES FALL TO -5C. MONDAY NIGHT INTO TUESDAY MORNING...MOSTLY CLEAR SKIES AND WEAKENING SURFACE WINDS WILL ALLOW FOR COLD CONDITIONS WITH LOWS MAINLY IN THE 30S. FREEZE WATCH IS IN EFFECT FOR WEST TN...NE AR...AND MO BOOTHEEL WHERE TEMPERATURES ARE EXPECTED TO DROP TO AT OR JUST BELOW 32 DEGREES. AREAS SOUTH OF THE WATCH AREA...A FROST ADVISORY MAY BE NEEDED WITH LOWS IN THE 30S...BUT READINGS ARE EXPECTED TO BE JUST ABOVE FREEZING WITH SLIGHTLY STRONGER SURFACE WINDS. USED A BLEND OF MODEL GUIDANCE DURING THIS TIME FRAME. TUESDAY WILL BE ANOTHER UNSEASONABLY COOL DAY WITH HIGHS IN THE 50S UNDER SUNNY SKIES. LIKE MONDAY...PREFERRED THE COLDER SIDE FOR MODEL TEMPERATURES. TUESDAY NIGHT INTO WEDNESDAY MORNING...THINK A WIDESPREAD FREEZE WILL OCCUR OVER THE ENTIRE MIDSOUTH AND FORECAST AREA...SO ADDITIONAL FREEZE WATCHES AND WARNINGS ARE LIKELY. SINCE THIS TIME FRAME IS BEYOND THE 5TH PERIOD...NO FREEZE WATCHES HAVE BEEN ISSUED YET AND THE FREEZE POTENTIAL IS COVERED IN THE HWO. WITH HIGH PRESSURE DIRECTLY OVERHEAD...CLEAR SKIES...AND CALM WINDS...TEMPERATURES SHOULD FALL RAPIDLY TUESDAY NIGHT. AGAIN WENT BELOW MODEL GUIDANCE AND THINK LOWS WILL BE IN THE 25 TO 32 DEGREE RANGE EVERYWHERE WITH COLDEST READINGS IN RURAL VALLEYS NEAR THE TN RIVER. TEMPERATURES MAY BE BELOW FREEZING FOR 5 TO 10 HOURS IN MANY SPOTS...WHICH MAY END THE GROWING SEASON. WILL BE CLOSE TO THE RECORD LOW OF 30 AT TUPELO SET IN 1976 AND PERHAPS THE ALL TIME OCTOBER LOW RECORD AT JACKSON TN OF 25 SET ON THE 29TH IN THE 1952. WEDNESDAY WILL BE A SUNNY DAY AND SLIGHTLY WARMER WITH HIGHS IN THE 57 TO 67 DEGREE RANGE. LOWERED THESE HIGHS SLIGHTLY AS THE STRENGTH OF COLD AIRMASS MOVING IN NOW APPEARS STRONGER THAN PREVIOUSLY THOUGHT. WEDNESDAY NIGHT THROUGH SUNDAY...TEMPERATURES WILL MODIFY TO NEAR OR SLIGHTLY ABOVE NORMAL DURING THIS TIME FRAME WITH MAINLY DRY CONDITIONS EXPECTED. THE LATEST ECMWF AND GFS MODELS HINT THAT A COLD FRONT MAY MOVE THROUGH LATE SATURDAY INTO EARLY SUNDAY. THE ECMWF INDICATED LIGHT RAINFALL WITH THE FRONT...BUT DECIDED TO KEEP THINGS DRY FOR NOW UNTIL THE GFS AND GEM AGREE WITH PRODUCING RAINFALL. HIGHS WILL MAINLY BE BETWEEN 65 AND 75 WITH LOWS MAINLY IN THE 40S. && .PRELIMINARY POINT TEMPS/POPS... MEM 75 42 55 36 / 0 0 0 0 MKL 73 38 53 31 / 0 0 0 0 JBR 74 39 53 32 / 0 0 0 0 TUP 75 42 57 34 / 0 0 0 0 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...FREEZE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY MORNING FOR CLAY-CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE-MISSISSIPPI- POINSETT-RANDOLPH-ST. FRANCIS. MO...FREEZE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY MORNING FOR DUNKLIN-PEMISCOT. MS...NONE. TN...FREEZE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY MORNING FOR CARROLL-CHESTER-CROCKETT-DECATUR-DYER-FAYETTE-GIBSON- HARDEMAN-HARDIN-HAYWOOD-HENDERSON-HENRY-LAKE-LAUDERDALE- MADISON-MCNAIRY-OBION-SHELBY-TIPTON-WEAKLEY. && $$ MBS