FXUS63 KOAX 012039
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
239 PM CST TUE DEC 1 2009

.SHORT TERM...TONIGHT THROUGH FRIDAY

DRASTIC CHANGE IN THE SENSIBLE WX EXPECTED DURING THE SHRT TERM.
SPLIT FLOW PATTERN CONTS ACRS THE CONUS TODAY. 12Z UPPR AIR ANLYS
INDCD POTENT UPPR LVL LO OVR SW TX IN THE SRN STREAM...BUT THIS WL
HAVE LITTLE IMPACT ON OUR FA. TWO SHRTWVS OF NOTE WERE MOVG THRU
THEN NRN STREAM...THE FIRST WAS OVR NW ND WITH THE UPSTREAM WV OVR
NW MT. H3 JET OF 110 KT WAS DIVING SWD INTO THE NRN ROCKIES
ASSOCIATED WITH THESE WX SYSTEMS. THIS IS GOING TO CAUSE A LARGE
TROF TO DEVELOP OVR THE NEXT 48 HOURS IN THE CNTRL US WITH ARCTIC
AIR SPILLING INTO THE REGION. EARLY AFTERNOON 19Z SFC ANLYS INDCD
CDFNT FM NEAR KDNS TO KTQE TO KOLU. THIS IS EXPECTED TO MAKE
STEADY PROGRESS SWD THRU THE FA...CLEARING THE SRN BORDER BY LATE
EVNG. CAA AND A STG PRES GRADIENT OVER NIGHT SHOULD KEEP THE
BOUNDARY LAYER MIXED AND HAVE WARMED LOWS A CAT OVR MOST OF THE
AREA DUE TO MIXING. CLDS WL GENERALLY BE INCREASING OVERNIGHT BUT
MUCH OF THIS SHLD BE THE MID AND HIGH VARIETY. SHLD SEE MIXING TO
AT LEAST H85 ON WED AND THIS SHLD OFFSET THE CAA SOME TO GET HIGHS
CLOSE TO NORMAL. NEXT SHOT OF COLD AIR WILL HEAD AT THE AREA ON
WED NIGHT INTO THE DAY ON THURS. THIS SHOT SHLD BE ASSOCIATED WITH
BETTER LO LVL MOISTURE AND A SC DECK MOVG INTO THE AREA LATE WED
NIGHT AND THRU THE DAY ON THURS. DECK IS PROGGED TO BE IN OR NEAR
THE DENDRITIC LAYER PER POINT FORECAST SOUNDINGS...AND THUS A FEW
FLURRIES ARE POSSIBLE BUT OVERALL LARGE-SCALE FORCING IS FOR
SUBSIDENCE AND THUS NOT EXPECTED ANYTHING SIG. MOST OF THE FLURRY
ACTION SHLD BE IN THE NRN AND NERN FA WHERE THE DEEPEST MOISTURE
IS PROGGED. ALTHOUGH CONDS ARE EXPECTED TO REMAIN COLD THRU
FRI...GENERAL TREND IN THE FORECAST WAS TO INCREASE HIGHS/LOWS
THRU FRI. LACK OF SNOW COVER TO THE NORTH AND GOOD MIXING WL ALLOW
FOR HIGHS TO RECOVER SOME...AND CLDS AND MIXING SHLD KEEP TMPS UP
A TOUCH OVERNIGHT THRU FRI.

BOUSTEAD

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY

AT THE BEGINNING OF THE FCST PD...MEDIUM RANGE MODELS IN PRETTY GOOD 
AGREEMENT DEPICTING A BROAD UPPER TROF ENVELOPING THE CONUS WITH TWO 
DISTINCT WAVES WITHIN THE NRN STREAM FLOW. ONE COMING ASHORE OVER 
THE PAC NW AND THE OTHER DROPPING OUT OF S-CNTRL CANADA. THE PAC NW 
WAVE AND ASSOCIATED COLD AIR INTRUSION THOUGH IS THE FEATURE OF 
INTEREST. WEAK LLVL MOISTURE BEGINS CREEPING NWD ALONG THE WESTERN 
HIGH PLAINS AND INTO THE CNTRL PLAINS BY SATURDAY AFTN. STILL WEAK 
LLVL MOIST AXIS SETS UP AHEAD OF THE CLOSING COLD FRONT SATURDAY 
NIGHT FROM ABOUT NERN IA TO SW KS. THE SFC BNDRY IS PROGGED TO 
ALREADY BE THRU THE CWA BY 12Z SUN...THEN GRADUALLY SLOWS DOWN AND 
FOR THE MOST PART STALLS OVER KS/MO TUESDAY MORNING. IN THE MEANTIME 
A NUMBER OF EMBEDDED IMPULSES WILL EJECT EWD THRU THE ROCKIES AND 
INTO THE CNTRL PLAINS. AT THIS POINT REALLY DON'T SEE MUCH POTENTIAL 
FOR PCPN DEVELOPMENT UNTIL MONDAY NIGHT/TUESDAY TIME FRAME WHEN 
STRONG 290K-295K UPGLIDE/MOIST ADV COMES INTO PLAY. ALL INDICATIONS 
ARE TEMPS WOULD BE COLD ENOUGH FOR VERY LIGHT SNOW. OTHERWISE... 
ANTICIPATE MAX/MIN TEMPS GENERALLY AOB NORM THRU THE FCST 
PD. 

DEE        

&&

.AVIATION...

TAF SITES KOFK/KOMA/KLNK 

18Z TAFS

COLD FRONT WILL CONTINUE TO MOVE THROUGH THE AREA THRU 00Z WITH
N-NW WINDS 15-25KT FOR MOST OF PERIOD PRIMARY CONCERN IN TAFS.
LITTLE LOW LEVEL MOISTURE BEHIND FRONT SO VFR CIGS SHOULD CONTINUE 
THROUGH THE PERIOD.

FOBERT

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.

&&

$$