FXUS64 KMRX 222035
AFDMRX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
330 PM EST TUE DEC 22 2009

.SHORT TERM (TONIGHT THROUGH THURSDAY)...STRONG STORM SYSTEM WILL BE 
EMERGING ACROSS THE PLAINS STATES ON WEDNESDAY WITH INCREASING 
MOISTURE AND TEMPERATURE ADVECTION DURING THE 24 TO 36 HOUR PERIOD 
ACROSS THE FORECAST AREA. ISENTROPIC LIFT WILL STRENGTHEN LATE 
WEDNESDAY NIGHT INTO THURSDAY WITH A SLIGHT CHANCE FOR A SHOWER 
ACROSS THE PLATEAU THROUGH SOUTHEAST TENNESSEE INITITIALLY AND THEN 
INCREASING PROBABILITY FOR SHOWERS FROM WEST TO EAST THROUGH THE DAY 
THURSDAY. STRONG CROSS TERRAIN FLOW WILL DEVELOP AS LOW LEVEL JET 
BUILDS EAST ACROSS THE SOUTHEASTERN U.S. USED STRONG SOUTHERLY WINDS 
IN THE HIGHER TERRAIN FOR THURSDAY. TRIED TO ACCOUNT FOR ADIABATIC 
WARMING AND ASSOCIATED PRECIPITATION SHADOW TO SOME EXTENT ACROSS 
SOUTHWEST VIRGINIA AND NORTHEAST TENNESSEE ON THURSDAY INDICATING 
SLOWER RISE IN PROBABILITIES HERE. STAYED CLOSE TO GUIDANCE TEMPS 
THROUGH THE PERIOD BUT UNCERTAINTY WILL EXIST WITH MINS OVER SNOW 
COVER ACROSS THE NORTH TONIGHT AND WEDNESDAY NIGHT AND MAX TEMPS 
COULD BE INTERESTING ACROSS NORTHERN PORTIONS OF THE GREAT VALLEY 
FOR THURSDAY AS WARMING MAY EXCEED GUIDANCE.
  
.LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)...SURFACE LOW BEGINNING 
TO FILL AS IT MOVES NE INTO THE GRTLKS EARLY IN THE PERIOD. COLD 
FRONT MOVES EAST THROUGH THE AREA EARLY FRI. CORE OF SW-NE UPPER JET 
STREAMS INTO THE AREA ON FRI AND CONTINUES JUST EAST OF THE S 
APPALACHIANS THROUGH THE WEEKEND. 

STRONG WINDS AND WIDESPREAD RAIN THURSDAY NGT WILL DECREASE WITH THE 
PASSING OF THE FRONT EARLY FRI. GOOD MID LEVEL DRY SLOT WITH THE 
EASTWARD SHIFT OF THE UPPER JET. LOWERED LOW CHC SNOW/RAIN SHWRS 
FOR THE WEEKEND. LOWERED TEMPS SLIGHTLY TO ACCOUNT FOR PROLONGED NW 
LOW LEVEL FLOW. ANOTHER SPOKE OF COLD AIR MOVES SE THROUGH THE AREA 
LATE ON SUN/EARLY MON. 

UPPER RIDGING BUILDS OVER AREA EARLY NEXT WEEK. NOT TOO EXCITED 
ABOUT WARM UP AS SURFACE RIDGE AXIS REMAINS S OF AREA. SOUTHERN 
STREAM SYSTEM COULD AFFECT AREA BY MID WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN             35  56  37  56  43 /   0  10  20  80  80 
KNOXVILLE MCGHEE TYSON AIRPORT, TN  33  51  36  54  41 /   0   0  10  50  80 
OAK RIDGE, TN                       31  51  36  52  40 /   0   0  10  60  80 
TRI CITIES AIRPORT, TN              26  47  29  54  34 /   0   0   0  20  80 

&&

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

&&

$$