FXUS64 KOHX 230936
AFDOHX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
336 AM CST WED DEC 23 2009
.DISCUSSION...
FORECAST REASONING WILL BE BASED ON A LEAN TOWARD THE EURO MODEL
SOLUTION FOR THE FORECAST PERIOD UNLESS OTHERWISE NOTED.
CURRENTLY...CLOUDY SKIES ACROSS THE MID STATE WITH TEMPS IN THE
LOWER TO MID 40S TO UPPER 30S...DEWPOINTS SPANNING THE 30S...
AND LIGHT SE WINDS. LIGHT RAINFALL APPROACHING THE TN RIVER VALLEY.
SFC GULF MOISTURE FETCH IN PLACE WITH STATIONARY FRONT POSITIONED TO
OUR NW. WEAK UPPER LEVEL RIDGING SE TO NW ACROSS THE MID STATE.
FORECAST QUANDARIES...STRONG STORM SYSTEM STILL EVIDENT ON WATER
VAPOR IMAGERY TURNING ACROSS THE SW U.S. THIS STRONG STORM SYSTEM
WILL BE MAIN WEATHER PLAYER FOR THE MID STATE THIS FORECAST PERIOD.
LATEST MODEL GUIDANCE STILL SHOWS THAT SYSTEM WILL PHASE WITH
NORTHERN STREAM ENERGY BY LATE THU...RESULTING IN POTENTIALLY
POWERFUL STORM SYSTEM OVER THE ERN 1/2 U.S. THRU EARLY NEXT WEEK.
SLY FLOW WILL STRENGTHEN STEADILY THRU THU AS SFC LOW MOVES INTO
N MO...AS UPPER LEVEL FLOW BECOMES PREDOMINATELY SWLY PER UPPER
LEVEL LOW ACROSS THE ERN PLAINS OF NM. WILL GO CLOSE TO NAM MOS
HIGHS THRU FRI. DEEP MOISTURE WILL INCREASE...BUT WITH LOW LEVEL
FLOW FROM THE SE...BOUNDARY LAYER WILL CONTINUE TO REMAIN PRETTY
DRY THRU 12Z THU...HOWEVER DO BELIEVE THAT MOST LOCATIONS WILL
EXPERIENCE SOME LIGHT RAINFALL ACROSS THE MID STATE. WILL CONTINUE
FORECAST TREND OF A W-E POP GRADIENT TODAY THRU 12Z THU....WITH
CATEGORICAL COVERAGE EXPECTED LATE THU INTO THU NGT...AS FRONT
EXPECTED TO OCCLUDE AND STRETCH FROM NEAR MOBILE BAY, AL...INTO
THE RED RIVER VALLEY REGION OF ND. A SIGNIFICANT UPPER LEVEL
TROUGH WILL DEVELOP ACROSS THE CNTRL U.S IN ASSOCIATION WITH
AN DEEPENING UPPER LEVEL LOW ACROSS THE CNTRL PLAINS...PROVIDING A
CONTINUANCE IN SWLY FLOW ALOFT. SHOWALTERS VALUES APPROACH ZERO
LATE THU AFTERNOON INTO THU NIGHT...SO ISOLATED TSTMS
POSSIBLE...AND CAN NOT RULE OUT THE POSSIBILITY OF A SHALLOW
CONVECTIVE LINE DEVELOPING ALONG AND AHEAD OF THE FRONT....AS IT
MOVES W TO E ACROSS THE MID STATE THU NIGHT.
GUIDANCE AND LMRFC GRAPHICS DEPICTING AREAL TOTAL QPF AMOUNTS WILL
GENERALLY RANGE FROM ONE INCH W TO AROUND ONE QUARTER OF AN INCH
ACROSS THE CUMBERLAND PLATEAU REGION. HOWEVER...WITH ISOLATED TSTMS
IN THE FORECAST FOR LATE THU AFTERNOON THRU THU NIGHT...ISOLATED
LOCATIONS COULD SEE HIGHER AMOUNTS. DO NOT BELIEVE THAT WE WILL
SEE THE HEAVY RAINFALL POTENTIAL THREAT THAT OUR NEIGHBORS MIGHT
EXPERIENCE TO OUR S.
MAIN FORECAST QUANDARY CENTERS AROUND THE POTENTIAL ISSUANCE OF A
WIND ADVISORY FOR THE MID STATE ON THU. AS STORM DEEPENS TO OUR
W...WINDS WILL STRENGTHEN THROUGH THE DAY THU. GFS/EURO ARE THE
STRONGEST...60+ KTS AT 925 MB OVER PARTS OF W PORTIONS OF THE MID
STATE STARTING AS EARLY AS 15Z THU. THE POTENTIAL EXIST FOR 25+ MPH
SUSTAINED WINDS AND GUSTS IN THE 40-45 MPH RANGE FROM 15Z THU TO
06Z FRI. IN AGREEMENT WITH MY NEIGHBORS TO MY W AND S ON THIS
REASONING. THUS..WILL HIGHLIGHT WIND THREAT WITH A WIND ADVISORY
ISSUANCE FROM LATE THU MORNING THRU THU EVENING.
UPPER LOW WILL THEN BASICALLY SIT AND SPIN OVER THE GREAT LAKES
THROUGH AT LEAST EARLY NEXT WEEK. THIS WILL LEAD TO A PERIOD OF MUCH
COOLER TEMPS...A TRANSITION FROM CLOUDY SKIES TO PARTLY CLOUDY
SKIES...AND CHANCE FOR LIGHT PRECIP MAINLY OVER THE PLATEAU THRU
SAT NIGHT...OF WHICH A RAIN/SNOW MIXTURE WILL BE POSSIBLE SAT AND
LIGHT SNOWFALL SAT NIGHT.
THANKS FOR INPUT HUN...LMK...AND JKL
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 56 46 58 42 / 60 70 100 100
CLARKSVILLE 55 45 58 41 / 80 70 100 100
CROSSVILLE 52 43 55 42 / 30 60 100 100
COLUMBIA 56 47 58 43 / 60 70 100 100
LAWRENCEBURG 55 47 58 44 / 80 70 100 100
WAVERLY 55 45 58 42 / 80 70 100 100
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 9 AM THURSDAY TO MIDNIGHT CST THURSDAY NIGHT
FOR TNZ005>011-022>034-056>066-075-077>080-093>095.
&&
$$
31/JBW