FXUS64 KMRX 120834
AFDMRX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
330 AM EST SAT DEC 12 2009
.SHORT TERM (TODAY AND TONIGHT)...SURFACE HIGH PRESSURE AND DRY AIRMASS
CONTINUE ACROSS THE AREA EARLY TODAY. STRONG ZONAL FLOW ALOFT. MOS
TEMP GUIDANCE HAS BEEN RUNNING WARM WITH THIS SYSTEM SO LEANED
TOWARD COOLER MAXS TODAY. 850-700 MB FLOW STRENGTHENS AND BACKS
THROUGH THE REMAINDER OF THE PERIOD. MOISTURE AND WARM AIR ADVECTION
FROM THE SW VERY DRAMATIC AS PCPN ADVANCES INTO THE AREA LATE TODAY
AND CONTINUES OVERNIGHT. 850 MB WINDS INCREASE OVERNIGHT AND A GOOD
WARMUP IS EXPECTED ACROSS THE HIGHER ELEVATIONS. VALLEY LOCATIONS
MAY BECOME TROUBLESOME OVERNIGHT ESPECIALLY AT THE ONSET OF PCPN.
NORTHERN AREAS WILL HAVE SOME TIME TO COOL AFTER SUNSET.
DRY AIRMASS AND LOW WET BULB TEMPS SUPPORT EVAPORATIVE COOLING
EARLY IN THE PCPN PROCESS. AM CONCERNED LOW LEVELS WILL NOT RECOVER
AND FREEZING RAIN BEGINNING TO LOOK LIKE A GOOD POSSIBILITY AT LEAST
FOR A FEW HOURS. SHELTERED VALLEYS ACROSS SW VA/NE TN MAY SEE
HAZARDOUS ICE ACCUMULATION. TEMPS WARM OVERNIGHT FROM THE SW AND
THREAT ACROSS CENTRAL AND SOUTHERN AREAS LOOKS SMALL.
.LONG TERM (SUNDAY THROUGH FRIDAY)...RAIN SHOWERS WILL CONTINUE INTO
EARLY SUNDAY AS THE SATURDAY NIGHT SYSTEM EXITS THE AREA. SHOWERS
WILL LINGER INTO THE AFTERNOON HOURS...SLOWLY ENDING FROM WEST TO
EAST DURING THE DAY. WILL BRIEFLY BE BETWEEN SYSTEMS SUNDAY NIGHT
AND MUCH OF MONDAY. HOWEVER...THE NEXT SYSTEM WILL APPROACH THE
REGION LATE MONDAY...AND SPREAD RAIN SHOWERS ACROSS THE AREA MONDAY
NIGHT AND TUESDAY. COOLER AIR PUSHES IN AS THE SYSTEM IS LEAVING
THE AREA AND LINGERING SHOWERS TUESDAY NIGHT COULD MIX WITH OR
CHANGE TO LIGHT SNOW OVER HIGHER TERRAIN BEFORE PRECIP ENDS
OVERNIGHT. THE REST OF THE EXTENDED SHOULD BE DRY WITH SURFACE HIGH
PRESSURE IN PLACE.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 44 38 51 41 66 / 60 100 50 10 20
KNOXVILLE MCGHEE TYSON AIRPORT, TN 44 36 50 40 63 / 30 100 60 10 10
OAK RIDGE, TN 44 36 49 40 63 / 30 100 50 10 10
TRI CITIES AIRPORT, TN 43 33 48 36 60 / 10 100 70 10 10
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
SON/MJB
