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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS64 KMRX 160724
AFDMRX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
324 AM EDT THU MAY 16 2013

.SHORT TERM /TODAY AND TONIGHT/...
-- Changed Discussion --
SOUTHWESTERLY FLOW WILL CONTINUE TO HELP TRANSPORT A WARM/MOIST
GULF AIRMASS INTO THE REGION TODAY AS AN UPPER-LOW OVER THE MID-
MISSISSIPPI VALLEY PUSHES OUT AN UPPER-LEVEL RIDGE THAT HAS BEEN
PROMOTING THE SUNNY AND CLEAR CONDITIONS ACROSS THE REGION FOR THE
PAST SEVERAL DAYS. THE COLDER TEMPERATURES ALOFT WILL HELP TO
CREATE SOME INSTABLITY...AND ALLOW FOR SOME SCATTERED DIURNALLY
DRIVEN CONVECTION DURING THE AFTERNOON AND EVENING. THIS ACTIVITY
MAY ALSO BE AIDED BY SOME LIFT FROM THE AFOREMENETIONED UPPER-LEVEL
DISTURBANCE...SO HAVE INCLUDED AT LEAST SLIGHT CHANCE POPS FOR BOTH
TODAY AND TONIGHT. THE WARM TEMPERATURES WILL CONTINUE...BUT MAY BE
A FEW DEGREES COOLER THAN WEDNESDAY GIVEN THE INCREASED CLOUD COVER
AND PRECIPITATION CHANCES.

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
A WARM AND MOIST AIRMASS LINGERS THROUGH THE LONG TERM PERIODS
WITH SLIGHT TO MODERATE INSTABILITY. THE CHALLENGE IS CHOOSING
WHICH DAYS HAVE THE BETTER FORCING AND COULD SEE 60 PERCENT OR
HIGHER COVERAGE OF TSRA. MODELS ARE MORE CONSISTENT AND IN BEST
AGREEMENT ON HIGHEST POPS JUSTIFIED FOR SATURDAY AT THIS POINT.
DAYTIME HEATING PLUS A WEAK UPPER LOW SUPPORTS PUSHING POPS UP TO
LIKELY OVER ALL BUT SE TN ON SATURDAY.

OTHERWISE...THE CLOSEST PROXIMITY OF THE FRONTAL BOUNDARY TO OUR
NORTH WILL BE FROM FRIDAY INTO SUNDAY...FAVORING SOMEWHAT HIGHER
POPS IN GENERAL FOR SW VA AND NE TN. HOWEVER...THE BEST TARGETS FOR
OPPORTUNITY TO BETTER GFSX MOS POPS DO APPEAR TO BE ON SUNDAY AND
MONDAY. THUS...STAYED CLOSE TO PREVIOUS FORECAST GRIDS FOR THOSE
PERIODS...WHICH IS 20 PERCENT OR MORE BELOW THE 16/00Z GFSX MOS POPS.

WEDNESDAY IS NOW TRENDING WETTER WITH A POTENTIAL COLD FRONT
APPROACHING...BUT STILL QUITE EARLY TO BUY HEAVILY INTO THIS TIMING.
KEPT POPS AROUND 40 TO 50 PERCENT WHICH IS VERY CLOSE TO GUIDANCE.
THE THREAT OF ANY ORGANIZED STRONG TO SEVERE STORMS IS VERY LOW AT
THIS TIME...PENDING THE DEVELOPMENT AND TIMING OF THE COLD FRONT
EARLY TO MID NEXT WEEK.

CLOSELY FOLLOWED THE 16/00Z GFSX MOS TEMPS...EXCEPT FOR AREAS WITH
HIGHEST POPS OVER THE WEEKEND.
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&&

.PRELIMINARY POINT TEMPS/POPS...
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CHATTANOOGA AIRPORT, TN             83  60  83  63  80 /  20  20  30  20  50
KNOXVILLE MCGHEE TYSON AIRPORT, TN  81  59  83  62  80 /  30  20  40  20  60
OAK RIDGE, TN                       82  58  83  61  80 /  30  20  40  20  60
TRI CITIES AIRPORT, TN              80  54  82  57  79 /  30  30  40  30  70
-- End Changed Discussion --

&&

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

&&

$$

AMP/TG