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000
FXUS64 KMRX 170842
AFDMRX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
442 AM EDT MON JUN 17 2013

.SHORT TERM...
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(TODAY AND TONIGHT)...MODELS PERFORMED RATHER POORLY ON
THE BATCH OF SHOWERS AND ISOLATED THUNDERSTORMS THAT MOVED ACROSS NE
PARTS OF THE FORECAST AREA AROUND MIDNIGHT TO 330 AM EDT. APPEARS
THAT THERE WILL BE AT LEAST A FEW HOURS LAG BEFORE MORE CONVECTION
MOVES IN FROM THE WEST AFTER SUNRISE. ALREADY SEEING EVIDENCE OF
THIS CONVECTION UPSTREAM OVER MIDDLE TN AND NE AL...SO AT LEAST
SOMEWHAT CONFIDENT IN INCREASING POPS FOR LATER THIS MORNING.
SOUNDINGS ARE MORE UNSTABLE THIS MORNING THAN LATER TODAY...SO ADDED
AT LEAST A MENTION OF THUNDERSTORMS. LOWERED POPS GENERALLY TO
CHANCE NORTH...BUT KEPT LIKELY POPS OVER SE TN AND SW NC. THIS IS IN
LINE WITH NAM MODEL DEPICTION AND ALSO NEEDED TO BLEND BETTER WITH
FFC AND GSP FORECAST GRIDS.

FOR TONIGHT...FRONTAL BOUNDARY SEEMS TO FINALLY SAG FURTHER SOUTH BY
12Z TUESDAY...WITH GENERAL CONSENSUS AMONGST MODELS ON THE NEXT
MAJOR WAVE OF CONVECTION APPROACHING LIKELY IN THE 06Z TO 12Z
TUESDAY PERIOD. FORECAST SOUNDINGS LOOK MORE UNSTABLE THAN EARLIER
THOUGHT...AS WELL AS SOME ELEVATED INSTABILITY AFTER 06Z TUESDAY.
THUS...I HAVE POPS INCREASING AFTER 06Z TUESDAY WITH SCATTERED
THUNDERSTORMS MENTIONED.

FOR TEMPS...JUST DON`T SEE MAX TEMPS GETTING NEAR THE GFS MOS VALUES
GIVEN THE ONGOING AND DEVELOPING CONVECTION. TRENDED CLOSE TO THE
PREVIOUS MAX TEMP GRID...WHICH WAS VERY CLOSE TO THE COOLER NAM MOS
HIGHS. MOS MINS LOOKED FINE FOR TONIGHT AND WERE FOLLOWED.

.LONG TERM...(TUESDAY THROUGH SUNDAY)...MODELS STILL BRINGING MAJOR
SHORTWAVE INTO FORECAST AREA TUESDAY AHEAD OF COLD FRONT. THIS WILL
AFFECT HIGHS WITH SHOWERS AND THUNDERSTORMS TUESDAY MORNING
DECREASING IN THE AFTERNOON. KEPT HIGHS BELOW GUIDANCE WITH
CONSIDERABLE CLOUDS AND PRECIPITATION. MODELS STILL HAVE FRONT
MOVING SOUTH OF THE FORECAST AREA TUESDAY NIGHT OR EARLY WEDNESDAY.
STILL WEAK SHORTWAVE ENERGY TO TRIGGER MORE ISOLATED SHOWERS AND
THUNDERSTORMS DURING THE AFTERNOON AND EVENING. PATTERN OF SLIGHT
CHANCE SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE END OF
THE WEEK AS THE TROUGH STAYS OVER THE EASTERN THIRD OF THE COUNTRY.
DRIER AND COOLER AIR BEHIND BOUNDARY WILL KEEP HIGHS NEAR TO
SLIGHTLY BELOW NORMAL WITH DEEPER MOISTURE STAYING SOUTH OF THE
FORECAST AREA. MODELS TRY TO STRENGTHEN RIDGE TO THE WEST AND GFS
TRIES TO DEVELOP WEAK UPPER LOW ALONG SOUTHEAST COAST ON THE
WEEKEND. THIS COULD INCREASE POPS OVER EASTERN SECTIONS BUT WILL
KEEP 20 TO 30 PERCENT AFTERNOON AND EVENING POPS FOR SATURDAY AND
SUNDAY.
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&&

.PRELIMINARY POINT TEMPS/POPS...
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CHATTANOOGA AIRPORT, TN             85  68  81  65  84 /  70  70  80  40  30
KNOXVILLE MCGHEE TYSON AIRPORT, TN  84  67  81  64  83 /  60  60  90  40  20
OAK RIDGE, TN                       84  67  80  64  83 /  60  60  80  40  20
TRI CITIES AIRPORT, TN              83  61  79  61  83 /  50  50  90  40  20
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&&

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

&&

$$

TG/TD