National Weather Service Text Product Display

Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN

Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

-- Highlight Changed Discussion --

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS64 KMRX 060256
AFDMRX

AREA FORECAST DISCUSSION...CORRECTED MIN TEMPS IN PRELIM SECTION
NATIONAL WEATHER SERVICE MORRISTOWN TN
955 PM EST THU DEC 5 2013

.DISCUSSION...
CURRENT SURFACE ANALYSIS SHOWS A STRONG COLD FRONT ALONG THE
CUMBERLAND PLATEAU...PRODUCING A SHARP TEMP GRADIENT RANGING FROM
THE UPPER 60S OVER THE GREAT TN VALLEY TO THE UPPER 30S OVER MIDDLE
TN. THIS COLD FRONT IS PROGGED TO ONLY SLOWLY DRIFT EASTWARD
TONIGHT...AS THE UPPER-LEVEL FLOW REMAINS PARALLEL TO THIS SURFACE
BOUNDARY. AREA RADARS REVEAL SCATTERED SHOWERS OVER THE FORECAST
AREA THIS EVENING...BUT SHOWER COVERAGE SHOULD INCREASE LATER
TONIGHT AS A BROAD UPPER-LEVEL TROUGH AMPLIFIES OVER THE ROCKIES AND
INCREASES LIFT OVER THE TN AND OHIO RIVER VALLEYS. TEMP FORECAST FOR
TONIGHT WILL BE VERY TRICKY DUE TO THE SHARP TEMP GRADIENT ALONG THE
COLD FRONT. AS A RESULT OF THIS SHARP GRADIENT...THE NAM AND GFS
GUIDANCE NUMBERS SHOW SOME DISCREPANCIES WITH THE MIN FORECAST FOR
TONIGHT. FOR NOW...WILL COMPROMISE BETWEEN THESE TWO SETS OF
GUIDANCE.

WILL ALSO UPDATE THE FORECAST THIS EVENING TO REMOVE ANY EVENING
PRECIP WORDING OF THUNDER. SOME ELEVATED THUNDER IS STILL BEING
OBSERVED OVER MIDDLE TN...BUT MODEL SOUNDINGS REVEAL A STABILIZING
AIR MASS OVER THE FORECAST AREA FOR TONIGHT.
&&

.PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --CHATTANOOGA AIRPORT, TN 58 68 39 47 40 / 100 100 100 20 100
KNOXVILLE AIRPORT, TN 56 68 38 48 36 / 100 100 100 20 90
OAK RIDGE, TN 51 63 36 44 36 / 100 100 100 20 90
TRI CITIES AIRPORT, TN 55 66 38 47 34 / 100 100 100 20 70-- End Changed Discussion --
&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&

DMG

National Weather Service National Headquarters