FXUS64 KJAN 100241 AAA
AFDJAN
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON MS
841 PM CST WED DEC 9 2009
.DISCUSSION...GOING FORECAST WAS ON TRACK WITH THE MAIN ELEMENTS. THE
ONLY ADJ TO THE GOING FORECAST WAS TO COOL THE HOURLY TEMPS QUITE A
BIT TO MATCH THE COLDER CONDITIONS SINCE THE SUN HAS SET.
WX CONDITIONS WILL BE QUIET THROUGH FRIDAY NIGHT WITH ONLY HIGH
CLOUDS STREAMING BY. A DEEPER LAYER OF CLOUDS WILL DEVELOP BY LATE
FRI AFTERNOON WITH INCREASING RAIN CHANCES FRI NIGHT INTO THE FIRST
HALF OF SAT. AT THIS TIME LOOKS LIKE JUST A COLD RAIN SETUP. /CME/
&&
.AVIATION...VFR CONDITIONS WILL PREVAIL THROUGH THE NEXT 48 HRS. THE
ONLY INTERESTING WX ELEMENT WILL BE THE SFC WINDS WHICH WILL CONTINUE
OUT OF THE N TONIGHT AROUND 5-8KTS AND THE MORE OUT OF THE NE ON THU
WITH SPEEDS AROUND 7-11KTS. LOOK FOR MVFR TO IFR CONDITIONS TO RETURN
FRI NIGHT AS THE NEXT ROUND OF RAIN DEVELOPS AND MOVES INTO THE
REGION.
&&
.PREV DISCUSSION... /ISSUED 230 PM CST WED DEC 9 2009/
DISCUSSION...THE PRIMARY WEATHER CONCERN IS THE RAIN CHANCES FOR
FRIDAY INTO FRIDAY NIGHT AND IF THE MOISTURE DELAYS AFTER THE WARMER
AIR COMES IN FOR RAIN ONLY CHANCES. ALSO DETERMINING THE COOL TEMPS
AND POPS FOR THE PERIOD.
LATEST SATELLITE IMAGERY SHOWED A BROAD UPPER TROUGH OVER
THE CONUS. A STRONG UPPER JET WAS HELPING TO BRING A SURGE OF
CANADIAN AIR INTO THE REGION. IR/VIS IMAGERY SHOWS SOME PATCHY HIGH
CLOUDS MOVING OVER THE REGION. THE CENTER OF THE CANADIAN HIGH WAS
NOTED ACROSS THE PLAINS. A SECONDARY SURGE OF COOL CANADIAN AIR WAS
MAKING THROUGH THE ARKLAMISS THIS AFTERNOON. BREEZY CONDITIONS HAVE
WEAKENED SOME OVER THE REGION.
FOR TONIGHT AND THURSDAY SURFACE HIGH PRESSURE WILL MOVE OVER THE REGION
DURING THE PERIOD AND THE CENTER WILL BE JUST NORTHEAST OF THE REGION
BY LATE THURSDAY AFTERNOON. UNDER A BROAD UPPER RIDGE THE REGION
WILL BE UNDER WEST TO NORTHWEST FLOW OVER THE REGION. FOR TONIGHT
WILL BE A COOL NIGHT WITH LOWS IN THE MIDDLE 20S TO LOWER 30S.
MAV LOOKED A LITTLE WARM WENT CLOSER TO MOS GUIDANCE...DESPITE THE
WET GROUND. CLEAR SKIES AND LIGHT WINDS WITH COLD AIR ADVECTION SHOULD
HELP TEMPS FALL INTO MAINLY THE 20S. FOR THURSDAY IT WILL BE A COLD
DAY DESPITE FULL SUNSHINE. AS THE SURFACE HIGH MOVES OVER THE REGION
HIGHS WILL ONLY REACH THE MIDDLE 40S TO LOWER 50S. WENT CLOSE TO MAV
GUIDANCE.
FOR THURSDAY NIGHT THROUGH FRIDAY NIGHT...THE SURFACE HIGH WILL RETREAT
TO THE EASTERN US DURING THE PERIOD. THIS WILL ALLOW SOME RETURN OF
GULF MOISTURE TO THE REGION. WE WILL SEE A RETURN TO WARMER AND
WETTER WEATHER FOR THE PERIOD. A WEAK DISTURBANCE IN THE SOUTHWEST
FLOW ALOFT WILL HELP DEVELOP A SURFACE LOW OVER THE WESTERN GULF.
THIS WILL RESULT IN ISENTROPIC LIFT INCREASING OVER OUR REGION AND
RAIN DEVELOPMENT FROM THE SOUTH FRIDAY. IT WILL LIKELY TAKE MOST OF
THE DAY TO MOISTEN UP AND THE 12Z GFS IS STILL FASTER THAN THE
ECMWF/NAM AND SREF IN BRINGING LIGHT RAIN INTO OUR SOUTHERN ZONES
BUT NOT UNTIL THE AFTERNOON. LIGHT RAIN IS EXPECTED TO THE HIGHWAY
84 CORRIDOR BY EVENING. THIS RAIN AREA WILL SPREAD NORTH THROUGH
FRIDAY NIGHT. THE MODELS CONTINUE TO BE A LITTLE SLOWER IN MOVING
RAIN BACK INTO OUR AREA FOR FRIDAY SO WILL HAVE A CHANCE TO WARM UP
BEFORE SEEING ANY RAINFALL. MAV POPS LOOKED A LITTLE HIGH FOR FRIDAY
SO CUT POPS DOWN SOME FOR THE AFTERNOON. FOR FRIDAY NIGHT WENT CLOSE
TO MAV POPS. INSTABILITY WILL BE RATHER WEAK SO TOOK OUT THE ISOLATED
THUNDER CHANCES IN THE SOUTH. AS FAR AS TEMPS ARE CONCERN WENT CLOSE
TO MAV GUIDANCE FOR THURSDAY NIGHT WITH LOWS FROM THE MIDDLE 20S
NORTHEAST TO THE LOWER 30S SOUTHWEST AS WE GET BACK TO SOME RETURN
FLOW. IT WILL BE ANOTHER COLD DAY FOR FRIDAY WITH HIGHS FROM THE
MIDDLE TO UPPER 40S AS WE REMAIN UNDER THE INFLUENCE OF THE COOL CANADIAN
HIGH. FOR FRIDAY NIGHT MADE SOME ADJUSTMENTS TO MAV GUIDANCE. IT LOOKED
TOO COOL IN THE NORTH WITH THE LOWER 30S AND WITH CLOUDS AND A COOL
RAIN AROUND PUT TEMPS IN THE MIDDLE 30S NORTH TO LOWER 40S
SOUTH./17/
PREV DISCUSSION...LONG TERM...SATURDAY THROUGH WEDNESDAY...
DRIER WEATHER IS INDICATED FOR SUNDAY BUT ANOTHER WAVE IS EXPECTED
TO BRING RAIN ON MONDAY. A STRONGER SHORTWAVE IS EXPECTED TO MOVE
OVER THE SOUTHERN PLAINS MONDAY AND HELP DEVELOP A SFC LOW THAT IS
PROGGED TO MOVE ACROSS OUR CWA MONDAY NIGHT. RAIN CHANCES WILL
INCREASE LATE SUNDAY NIGHT AHEAD OF THE THIS SYSTEM AND LAST THROUGH
MONDAY. BOTH GFS AND ECMWF SHOW A STRONG COLD FRONT DROPPING INTO
OUR REGION TUESDAY MORNING WITH COLDER AND DRIER WEATHER SLATED FOR
WEDNESDAY. /22/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 29 48 30 49 / 0 0 0 13
MERIDIAN 29 48 27 46 / 0 0 0 14
VICKSBURG 29 48 31 49 / 0 0 0 12
HATTIESBURG 33 53 31 48 / 0 0 0 20
NATCHEZ 29 49 33 49 / 0 0 0 20
GREENVILLE 28 45 29 47 / 0 0 0 9
GREENWOOD 26 45 28 47 / 0 0 0 12
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
CME/
