FXUS63 KOAX 042116
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
316 PM CST FRI DEC 4 2009
.SHORT TERM...TONIGHT THROUGH MONDAY.
LATEST MODELS IN PRETTY GOOD AGREEMENT DEPICTING AN AMPLIFYING UPPER
RIDGE OVER THE ERN PAC WILL RESULT IN AN UPPER TROF DIGGING SWD OVER
THE WRN CONUS....WITH LARGE SCALE FLOW FOR THE MOST PART BECOMING
NEARLY STAGNANT EARLY NEXT WEEK. MAIN FEATURE OF INTEREST IS FOCUSED
ON POTENT WRN IMPULSE GETTING EJECTING OVER THE ROCKIES SATURDAY
NIGHT THEN INTO THE CNTRL PLAINS ON SUNDAY...AND WHERE RESULTING
SNOWFALL WILL BE. SYNOPTIC FORCING INCREASES THRU THE DAY WITH GOOD
GULF MOISTURE FEEDING INTO THE SYSTEM. GIVEN TRACK OF 500MB HFC AND
LOCATION OF MOIST DENDRITIC LIFT...INDICATIONS ARE THAT FOCUS FOR
SNOW ACCUMULATIONS(AROUND 2 INCHES) SHOULD GENERALLY HAPPEN OVER
N-CNTRL/NERN KS THRU SUNDAY EVENING. MEANWHILE ANTICIPATE AREAS
GENERALLY SOUTH OF THE CWA I-80 CORRIDOR HAVE THE POTENTIAL FOR
AROUND AN INCH DURING THIS TIME. VORT ENERGY QUICKLY EXITS THE AREA
AFT 06Z MON WITH SUBSIDENCE FILTERING INTO THE CNTRL PLAINS. BY
MONDAY GRADUAL 500MB HGT INCREASES TAKE PLACE IN RESPONSE TO NEXT
SYSTEM DIGGING OVER THE WRN CONUS WITH STRONG MID LYR WAA ENSUING
OVER THE REGION. MOISTURE RETURN THOUGH IN QUESTION AT THIS POINT
AND WILL THEREFORE OPT TO CONTINUE DRY FCST FOR MONDAY.
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY.
...A WINTER STORM MAY AFFECT THE CENTRAL PLAINS MONDAY NIGHT AND
TUESDAY EVENING...
YESTERDAY...THE ECMWF STARTED TO SHOW THIS STORM...AND TODAY...THE
ECMWF/GFS/GEM...ALL HAVE THE WEST COAST TROF MOVING INTO THE ROCKIES
MONDAY NIGHT WITH SNOW EXPANDING EASTWARD ACROSS THE PLAINS. H85
WINDS ARE PROGGED TO TRANSPORT MOISTURE NORTHWARD...WITH STRONG
ISENTROPIC LIFT/THETA-E ADVECTION ACRS OK INTO KS AND NEBRASKA A
TROWAL FM KS INTO MO AND INCREASING UVV. TUESDAY...THE MODELS
DIFFER ON THE SFC TRACK...WITH THE GFS/GEM TAKING IT ACRS SRN KS AND
THE ECMWF WITH A FARTHER SOUTH TRACK ACRS OK. THE PATH OF THE STORM
WILL DETERMINE THE HEAVY SNOW SWATH AND THESE LATITUDINAL
DIFFERENCES CAN MAKE A BIG DIFFERENCE ON THE FCST. THE GFS HAS
TRACKED FARTHER NORTH WITH TIME...HOWEVER THE ECMWF HAD TRACKED
FARTHER SOUTH FROM YESTERDAY/S RUN. TIME-SECTIONS POINT TO SOME
SYMMETRIC INSTABILITY ATOP THE FRONTOGENESIS DURING THE TIMING OF
MAXIMUM LIFT MONDAY NIGHT AND TUESDAY. SNOW FORECASTING TECHNIQUES
YIELD THE POTENTIAL FOR SIX TO TWELVE INCHES OR MORE OF SNOW WITH
THIS STORM SYSTEM...ACCOMPANIED BY COLD TEMPERATURES AND NORTH WINDS
OF 15 TO 30 MPH WITH STRONGER GUSTS. WILL CONTINUE TO MONITOR THIS
DEVELOPING STORM. HAVE INCREASED POPS FOR THE MONDAY NIGHT THROUGH
TUESDAY EVENING PERIOD AND WILL CONTINUE TO DISCUSS IN THE HWO.
THE STORM MOVES OUT FOR WEDNESDAY...HOWEVER VERY COLD TEMPERATURES
HAVE BEEN PULLED SOUTHWARD. WITH EXPECTED SNOW COVER...HAVE
ADJUSTED TEMPERATURES FOR TUESDAY-THURSDAY TO BE 10 TO 20 DEGREES
COLDER THAN NORMAL. ANOTHER WAVE IS FORECAST TO MOVE THROUGH FRIDAY
AND THIS MAY BRING SNOW OR SNOW/RAIN TO THE AREA THURSDAY NIGHT AND
FRIDAY. &&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
ISOLATED FLURRIES HAD DEVELOPED BY LATE MORNING ALONG WITH SPOTTY
MVFR CIGS. CLOUDS HAVE ALREADY CLEARED KOFK...AND SHOULD CLEAR KLNK
BY 23Z-00Z...AND KOMA BY 00Z-01Z. VFR CONDITIONS EXPECTED THEREAFTER.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
DEE/CZ/DEWALD
