000
FXUS63 KOAX 190835
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
335 AM CDT FRI MAR 19 2010
.DISCUSSION...
SYNOPSIS...00Z UPPR AIR ANLYS INDCD 110 KT H3 JET DIVING SWD THRU
THE NRN ROCKIES. DOWNSTREAM...A 100 KT H3 NRN PLAINS JET EXTNDD FM
THE DAKOTAS INTO THE GREAT LAKES. TWO WELL DEFINED SHRTWV TROFS
WERE ASSOCIATED WITH THE JET...THE FIRST OVR NV AND THE SECOND OVR
ID. AT H7 STG THERMAL GRADIENT EXTNDD FM NRN CO INTO ERN SD WITH
A DECENT AMOUNT OF MID LVL MOISTURE BEHIND IT. AT H85 INITIAL
CDFNT EXTNDD FM SRN MN INTO NE CO WITH THE SECOND CDFNT OVR NRN
ND. 08Z SFC ANLYS INDCD CDFNT FM CNTRL IA INTO SE NEB. REGIONAL
RADAR MOSAIC INDCD A PERSISTENT BAND OF PRECIP OVR NRN NEB.
FORECAST...GOING FORECAST LOOKS GENERALLY ON TRACK FOR TODAY AND
TONIGHT. SFC CDFNT WL CONT TO RACE SWD THRU THE DAY TODAY. UPPR LVL
HEIGHTS WL ALSO BE FALLING THRU THE DAY AND THIS WL ALLOW FOR STG
MID LVL THERMAL GRADIENT TO DROP SWD AS WELL. THIS WL BE THE
PRIMARY FORCING MECHANISM FOR PRECIP FOR TODAY. CWA WL GENERALLY
SEE A LACK OF STG Q-G FORCING TODAY AS THE TWO PREVIOUSLY
MENTIONED SHRTWV TROFS REMAIN WELL WEST OF THE FA. THERE IS SOME
SUPPORT FOR LARGE-SCALE ASCENT OVR THE FA TODAY AS NEB/IA WL
RESIDE IN THE RIGHT ENTRANCE REGION OF THE NRN PLAINS JET. CROSS
SECTIONS ACROSS THE FRONTAL ZONE INDCS A WELL DEVELOPED FRONTAL
CIRCULATION...BUT FAIRLY STABLE AS MOST OF THE EPV REMAINS ABOVE
ZERO. NEVERTHELESS...GIVEN THE MARGINALLY FAVORABLE LARGE- SCALE
FORCING AND STG FRONTOGENESIS...SHLD SEE WIDESPREAD PRECIP MOV
THRU THE FA TODAY. TIMING OF CHANGE OVR FM RA TO SN LOOKS PRETTY
CONSISTENT FM PREVIOUS FORECAST AND LITTLE CHANGE WAS MADE HERE.
PRECIP SHLD START OFF FROZEN IN NE NEB THIS MRNG...CHANGE ARND
16-18Z ALNG I-80...AND CLOSER TO LATE AFTN OVR THE FAR S.
SNOW AMOUNTS ARE STILL A LITTLE PROBLEMATIC. SFC TMPS OVR THE WRN
FA WILL FALL FASTER DURING THE DAY...AND THUS SN WL HAVE A BETTER
CHANCE OF ACCUMULATING. ALNG AND E OF HIGHWAY 75...TMPS SHLD
REMAIN GENERALLY IN THE MID 30S AND THUS ACCUMS WL MAINLY BE ON
GRASSY SFCS. THUS HAVE 2 TO 4 GOING IN THE WEST TODAY...AND 1-3 IN
THE EAST. NRN WINDS WILL ALSO BE BREEZY TODAY WITH 15-30 MPH
EXPECTED. WE ARE NOT EXPECTING MUCH IN THE WAY OF BLOWING SN THOUGH
DUE TO THE FAIRLY WET NATURE OF THE SN. THUS WL NOT ISSUE AN ADVRY
ATTM...BUT THE WRN FA WL HAVE TO BE WATCHED TODAY.
MID LVL FRONTOGENESIS BAND THEN DROPS INTO THE SRN CWA THIS EVNG.
PRECIP CHANGE TO SN SHLD BE COMPLETE BY MID EVNG THERE. MID LVL
FRONTOGENESIS BAND WL LIKELY STALL FOR A TIME THIS EVNG OVR THE SRN
CWA AS WRN US DVLPG TROF STARTS TO BOTTOM OUT AND SHIFT SLOWLY
EWD. THIS IS A LITTLE CONCERNING AS THIS CLD LEAD TO MORE THAN A
FEW HOURS OF STG LIFT. ALSO THE STABILITY GETS WEAKER AS THE FNT
DROPS FARTHER SOUTH. THIS ALNG WITH A GOOD PART OF THE SN FALLING
WHILE DARK ALLOWS FOR HIGHER ACCUMULATIONS. ONCE YOU ARE ABLE TO
ACCUMULATION AN INCH OF TWO...WARM GROUND TMPS HAVE LITTLE FURTHER
AFFECT. HAVE A GENERAL 3 TO 6 INCH THIS AREA FM FBY TO BIE TO AFK
TO RDK AND S. THOUGHT ABOUT A WNTR STRM WATCH FOR THIS AREA AS
SOME CONCERN THAT SOME AMOUNTS CLD GET CLOSE TO 6...BUT WL HOLD
OFF AND LET THE DAY SHIFT TODAY ANOTHER LOOK. CERTAINLY SOME TYPE
OF ADVRY WL BE NEEDED LATER.
AS SYSTEM MOVS INTO THE SRN PLAINS ON SAT...FORCING WL SHIFT SWD
AND CLEARING SHLD MOV IN FM THE NORTH. OTHER THAN INCREASING SOME
HIGHS ON SUN/MON...LITTLE CHANGE TO THE FORECAST PAST SAT.
BOUSTEAD
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
COLD FRONT HAD MOVED THROUGH ALL THREE SITES AT 07Z WITH INCREASING
NORTH WINDS THRU 12Z. MVFR CONDITIONS EXPECTED TO SPREAD SOUTH AND
INTO ALL SITES AFTER 12Z WITH RAIN/SNOW AFTER 15Z AND ALL SNOW AFTER
18Z. OCCASIONAL IFR CIGS AND VSBYS AFTER 18Z.
FOBERT
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
