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000
FXUS64 KJAN 092030
AFDJAN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
230 PM CST TUE FEB 9 2010

.SHORT TERM...TONIGHT THROUGH THURSDAY...THE CLOSED LOW OVER THE MID
MISSISSIPPI VALLEY THIS AFTERNOON WILL CONTINUE MOVING EAST TONIGHT
ACROSS THE OHIO VALLEY. AS IT DOES...THE REMAINING CLOUDS OVER EAST
MISSISSIPPI WILL CLEAR FROM THE WEST EARLY THIS EVENING. OVERNIGHT
THERE COULD BE A FEW HIGH THIN CLOUDS ASSOCIATED WITH A +180KT JET
STREAK MOVING OVER OUR REGION...OTHERWISE CAA WILL CONTINUE OVER OUR
AREA TONIGHT AS A COLD CANADIAN CENTER OF HIGH PRESSURE SETTLES OVER
THE CENTRAL PLAINS. STRONG GUSTY NORTHWEST WINDS WILL CONTINUE THIS
AFTERNOON AND WL KEEP THE LAKE WIND ADVISORY IN EFFECT UNTIL 6 PM.
THE GUSTY CHARACTER OF THE WINDS WILL DIMINISH THIS EVENING ALONG
WITH GRADUALLY LIGHTER WIND SPEEDS. IT WILL BE A COLD NIGHT AS ALL
SITES WILL BOTTOM OUT IN THE 20S. NORTHWEST WINDS ALOFT WILL SLOWLY
BACK TO THE WEST WEDNESDAY WHILE THE SURFACE HIGH SHIFTS EAST OVER
OUR REGION. THIS WILL CONTRIBUTE TO DRY CONDITIONS WEDNESDAY AND
MILDER TEMPERATURES. HOWEVER...TEMPERATURES WILL REMAIN 10 TO 15
DEGREES BELOW SEASONAL AVERAGES...WITH HIGHS IN THE 40S. WINDS ALOFT
WILL CONTINUE BACKING WEDNESDAY NIGHT AHEAD OF A CLOSED LOW THAT
WILL BE MOVING OVER SE ARIZONA/SW NEW MEXICO BY THURSDAY MORNING.
THIS WILL BRING AN INCREASE IN HIGH LEVEL CLOUDS WEDNESDAY NIGHT BUT
TEMPERATURES SHOULD HAVE NO PROBLEM DROPPING INTO THE 20S AGAIN AT
MOST LOCATIONS. COME THURSDAY...THE SURFACE HIGH IS EXPECTED TO BE
CENTERED OVER THE TENNESSEE VALLEY WHICH WILL KEEP COOL DRY
CONDITIONS GOING OVER OUR REGION AS WEAK CAA CONTINUES. ATOP THIS
AIRMASS WAA WILL BE INCREASING AHEAD OF THE APPROACHING UPPER LEVEL
LOW OVER WEST TEXAS AND THE DEVELOPING SURFACE LOW OVER THE
SOUTHEAST TEXAS COAST. THIS WILL RESULT IN A THICKENING AND LOWERING
MID LEVEL CLOUD DECK FROM THE SOUTHWEST. THE INCREASING CLOUDS WILL
LIMIT INSOLATION AND HOLD TEMPERATURES WELL BELOW NORMAL AGAIN. PWS
WILL START OFF BELOW A HALF INCH AND IT WILL TAKE SOME TIME TO
MOISTEN THE COLUMN ENOUGH TO GET MEASURABLE PRECIPITATION AT THE
SURFACE. STILL...MODELS SUGGEST SOME PRECIPITATION OVER THE WESTERN
TWO THIRDS OF THE BY LATE THURSDAY AFTERNOON. MODEL SOUNDINGS
SUGGESTS A MIX OF LIGHT RAIN AND LIGHT SLEET WILL BE POSSIBLE.
SURFACE TEMPERATURES WILL BE ABOVE FREEZING THURSDAY AFTERNOON SO NO
WINTRY MIX ACCUMULATIONS ARE EXPECTED. GUIDANCE TEMPERATURES WERE
REMARKABLY CLOSE THROUGH THURSDAY AT MOST SITES BUT HAVE GONE A FEW
DEGREES BELOW MAX TEMPERATURES THURSDAY. THE FORECAST GETS A LITTLE
TOUGHER GOING INTO THURSDAY NIGHT AS THEY DIVERGE ON THE EVOLUTION
AND POSITIONS OF THE CLOSED LOW AND SURFACE LOW. THE OPERATIONAL GFS
APPEARS TO BE THE OUTLIER IN SUFFERING SOME CONVECTIVE FEEDBACK AND
TAKING THE SURFACE LOW EAST SOUTHEAST TOWARD THE FLORIDA STRAITS.
THE ECMWF HAS SUPPORT FROM THE UKMET AND CANADIAN. FOLLOWING THIS
SCENARIO...A SIGNIFICANT SNOWFALL EVENT FOR THE ARKLAMISS STILL
LOOKS ON TRACK FOR THURSDAY NIGHT INTO FRIDAY. THE PREVIOUS
DISCUSSION HANDLES THIS BELOW. /22/

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...THE FOCUS OF THIS
FORECAST IS ON THE POTENTIAL HEAVY SNOW EVENT FOR THU NIGHT INTO THE
FIRST HALF OF FRI. ASIDE FROM THAT...TEMPS WILL BE THE OTHER FOCUS.

THE MAIN EVENT/PRECIP WINDOW WILL BE THU NIGHT INTO THE FIRST HALF
OF FRI. THE LATEST MODEL DATA IS NOT IN THE BEST OF AGREEMENT...BUT
SOME SIMILARITIES EXIST AND HAVE BEEN CARRIED FROM THE PREV RUNS.
THE LATEST WITH THE GFS IS THAT IT IS MORE SUPPRESSED. THE SFC LOW
IS FURTHER SOUTH AND AS A RESULT...THE BEST ASCENT AND PRECIP
GENERATION REGION IS FURTHER S CLOSER TO I-10. IN TURN...THE OVERALL
ATMOSPHERE IS A TAD COLDER WHICH LEADS TO INCREASED CONFIDENCE THAT
PRECIP TYPE WILL BE ALL SNOW AFTER THE INITIAL LIGHT SLEET MIX. THE
EURO IS SIMILAR TO ITS PREV RUNS...A BIT WETTER...AND CLOSE TO THE
EARLIER GFS RUNS. IT TO IS A TAD COLDER AND PAINTS A SNOWIER
PICTURE. THE SREF AND GFS ENSEMBLE DATA IS MORE OF A BLEND OF THE
EURO/GFS AND IS THE WAY I WILL BE LEANING. THE SREF IS SLOWER AND IT
HAS MORE OF A NAM FLAVOR. I DON`T LIKE THE REAL SLOW SOLUTION AS
THOSE ARE OUTLIERS...SO A SLIGHTLY SPED UP SREF FITS GOOD WITH A
BLEND OF THE EURO/GFS. THE MAIN TIMEFRAME WILL WILL FOCUS MEASURING
SNOW AND ANY ACCUMULATING SNOW WILL BE BETWEEN 9 PM AND 10 AM...WITH
SOME STILL POSSIBLE A FEW HRS EITHER SIDE OF MY PREDICTED WINDOW.

AT THIS TIME...BASED OFF THE RECENT TRENDS FROM PREV RUNS AND PAST
EVENTS...THE MAIN AREAS THAT I EXPECT TO SEE MEASURABLE SNOW WILL BE
FOR LOCATIONS ALONG AND S OF I-20 WITH THE BEST POTENTIAL WITH IN
THE HWY 84 CORRIDOR. AMOUNTS BETWEEN 2-4 INCHES SEEMS STILL A GOOD
FIRST GUESS WITH SOME LOCATIONS SEEING A BIT MORE.
ADDITIONALLY...THE FURTHER N YOU GO...LIMITED MOISTURE AND BEING A
BIT REMOVED FROM THE BEST ASCENT SHOULD ONLY YIELD AN INCH OR SO.
NOW...THIS IS JUST MY BEST GUESS BASED OFF THE PREV MODEL RUNS AND
TRENDS FROM THE LATEST DATA. THERE STILL SEEMS TO BE DECENT SPREAD
IN THE MODEL GUID AND WITH THE TRACK OF THE GULF LOW STILL QUITE
UNCERTAIN...EXPECT THINGS TO CHANGE SOME WITH EACH MODEL RUN. LETS
HOPE THAT WITH THE FEATURE OF INTEREST JUST NOW COMING ONSHORE IN
CENTRAL CA...THAT THE MODELS WILL QUICKLY PICK UP ON A SOLUTION AND
CONVERGE TO SOMETHING IN THE NEXT 24-36HRS.

ANOTHER PRIMARY FORECAST ISSUE FOR FRI IS TEMPS. FOR SOME
REASON...GUID TEMPS ARE VERY WARM FOR HIGHS WITH VALUES RANGING FROM
THE LOWER/UPPER 40S. I WILL BE CUTTING THOSE SIGNIFICANTLY. WITH THE
COMBINATION OF SNOWY PRECIP FALLING/LINGERING INTO MIDDAY AND THEN
CLOUDS LASTING THROUGH THE DAY ALONG WITH AT LEAST SOME WEAK
CAA...TEMPS SHOULD ONLY REACH THE MID/UPPER 30S AT BEST.

IN THE WAKE OF THE THU/FRI SYSTEM...SFC HIGH PRESSURE LOOKS TO
SETTLE OVER THE REGION FOR SAT/SAT NIGHT. BY SUN...ALL GUID IS
INDICATING A POTENT UPPER LOW WILL DIVE SE OUT OF THE N PLAINS AND
HELP TO CARVE OUT A FAIRLY LARGE E CONUS TROUGH FOR EARLY WEAK. AS
THIS OCCURS...A SOLID COLD FRONT WILL CROSS THE REGION SOMETIME LATE
SUN INTO EARLY MON AND RE-ENFORCE THE COLD CONDITIONS AND BELOW
NORMAL PATTERN. AS FOR TEMPS SAT-TUE...GUID VALUES WERE GENERALLY
GOOD AND ACCEPTED. THE ONLY MAJOR ADJ WAS TO WARM SUN HIGHS AS THE
00Z GFS WAS TOO QUICK WITH THE FROPA AND GOING WITH A SLOWER/WARMER
SOLUTION FIT BEST. /CME/

&&

.AVIATION...LATEST SATELLITE IMAGERY SHOWS THE CLEARING LINE HAS
ADVANCED QUICKLY ACROSS THE REGION TODAY. IT EXTENDED JUST SOUTHEAST
OF THE NATCHEZ TRACE. MVFR CEILINGS WAS NOTED WITH THE CLOUD DECK OF
1500-2300 FEET. EXPECT SKIES TO CLEAR FOR THE REMAINDER OF THE
REGION BY THIS EVENING FOR VFR CONDITIONS. A FEW LOW-LEVEL CLOUDS
WILL DRIFT SOUTHEASTWARD ACROSS THE REGION TONIGHT. GUSTY NORTHWEST
WINDS ARE EXPECTED TO IMPACT THE REGION FOR THE REMAINDER OF THE
AFTERNOON...WITH SPEEDS OF 15 TO 20 KT AND GUSTS BETWEEN 23 AND 28
KT. NORTHWEST WINDS WILL DIMINISH TO 7 TO 13 KT AFTER 10/0000 AND
CONTINUE INTO WEDNESDAY MORNING. EXPECT VFR CONDITIONS FOR WEDNESDAY
WITH WINDS FROM THE NORTHWEST AT AROUND 8 TO 10 KNOTS. /17/


&&

.PRELIMINARY POINT TEMPS/POPS...
JACKSON       26  46  28  43 /   2   2   4  26
MERIDIAN      25  46  25  44 /   2   2   5  16
VICKSBURG     27  46  28  43 /   2   2  11  35
HATTIESBURG   26  50  29  48 /   2   2   7  19
NATCHEZ       27  46  28  43 /   2   2  13  47
GREENVILLE    26  42  25  41 /   2   2   5  25
GREENWOOD     26  43  25  41 /   2   2   4  19

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...LAKE WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR MSZ018-019-
     025>066-072>074.

     WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR MSZ026-030-031-043-
     049-052.

LA...LAKE WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR LAZ007>009-
     015-016-023>026.

     WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR LAZ009.

AR...LAKE WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR ARZ074-075.

     WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR ARZ075.

&&

$$
22/CME/17