038 
FXUS63 KOAX 210535
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
1135 PM CST SUN JAN 20 2013

.AVIATION...
06Z TAFS FOR KOMA...KOFK...KLNK

A BAND OF SC HAS DEVELOPED ALONG THE LEADING EDGE OF THE NEXT PUSH 
OF COLDER AIR INTO THE TERMINALS. THIS HAS LED TO SOME -SN AT OFK 
THIS EVNG AND WILL ALSO LIKELY LEAD TO SOME FLURRIES AT OMA B/W 06 
AND 09Z. OTHERWISE THIS DECK...THAT IS GENERALLY AOA 3 K FT...SHOULD 
CLEAR ALL 3 TERMINALS BY MORNING. THE LATEST SURFACE ANALYSIS 
INDICATES THE PRESSURE RISES ARE HEADING TOWARD OFK AND THIS SHOULD 
LEAD TO AN INCREASE IN THE WINDS SHORTLY...AND THEN OMA/LNK AT ABOUT 
08/09Z WITH SOME GUSTS LIKELY AT OMA/OFK INTO EARLY MON. THE SC DECK 
CURRENTLY OVER THE AREA IS LIKELY TO BE REPLACED WITH MID LEVEL CIGS 
THROUGH THE DAY ON MON. THESE MAY TEND TO LOWER TOWARD THE END OF 
THE PERIOD WITH SOME -SN POSSIBLE JUST AFTER 06Z. 

BOUSTEAD

&&

.PREV DISCUSSION... /ISSUED 306 PM CST SUN JAN 20 2013/ 

SHORT TERM...TONIGHT THROUGH WEDNESDAY 
LIGHT SNOW IS TAPERING TO FLURRIES IN THE NORTHEAST CWA...WITH
CLOUDS ACROSS MUCH OF THE AREA. SUBJECTIVE 12Z UPPER AIR ANALYSIS
INDICATES BROAD UPPER- LEVEL TROUGHING ACROSS THE CENTRAL AND
EASTERN CONUS...WITH A WEAK UPPER LOW OFF THE COAST OF SOUTHWEST
CA. 125- 140KT JET STREAK EXTENDED FROM CENTRAL ND THROUGH
NORTHEAST SD/SOUTHERN MN INTO CENTRAL WI...THEN ACROSS TO THE
EASTERN GREAT LAKES. SUB-0C TEMPS AT 850MB EXTENDED AS FAR SOUTH
AS NORTHERN MO/NORTHERN KS/SOUTHWEST CO...WITH STRONGEST GRADIENT
TO SUB--15C TEMPS ACROSS SD/IA/NORTHERN IL TO THE MI/IN-OH BORDER.
THOUGH THE MAIN 850MB LOW WAS CENTERED IN EASTERN ONT/WESTERN
QB...A WEAK 850MB LOW WAS NOTED IN SOUTHWEST SD/WESTERN NEB. BAND
OF LIGHT SNOW WAS FOLLOWING FAIRLY CLOSE TO THE 850MB
FRONTOGENETIC REGION...WHICH HAD SLID INTO CENTRAL IA AT 20Z.
SURFACE HIGH WAS BUILDING INTO THE DAKOTAS...WITH WINDS REMAINING
OUT OF THE NORTHWEST ACROSS THE PLAINS. CLOUDS EXTENDED FROM
WESTERN MT THRUGH SD/NE/IA INTO NORTHERN KS/NORTHERN MO/NORTHERN
IL.

THOUGH OVERALL FORECAST IS FAIRLY BENIGN...NIGGLING ISSUES LIKE NEAR-
ADVISORY WIND CHILLS TONIGHT AND NEAR-MEASURABLE LIGHT SNOW OR 
FLURRIES ON MONDAY NIGHT INTO TUESDAY MORNING WILL ADD CHALLENGES.  
FOR TONIGHT...AM SEEING A BAND OF BKN-OVC CLOUDS EXTENDING WELL 
UPSTREAM AND NEARLY PARALLEL TO THE MID- TO UPPER-LEVEL FLOW.  THINK 
CLOUDS WILL BREAK SOMEWHAT TONIGHT...BUT ALSO THINK CLOUDS WILL HANG 
ON LONGER THAN INITIALLY THOUGHT.  WITH THAT AND WITH WINDS 
REMAINING ABOVE 1OKT ALL NIGHT...ALONG WITH HAVING NO 
SNOWPACK...HAVE BUMPED UAVIATION...
18Z TAFS FOR KOFK...KOMA AND KLNK.

A BAND OF LIGHT SNOW WILL CONTINUE TO DROP EAST SOUTHEAST ACROSS
NORTHEAST NEBRASKA AND WEST CENTRAL IOWA THIS AFTERNOON. A FEW
LIGHT FLURRIES ARE POSSIBLE AT KOFK AS WELL AS KOMA THROUGH THE
AFTERNOON. KOFK CONDITIONS MAY DROP TO MVFR FOR A FEW HOURS BUT
OTHERWISE SHOULD REMAIN VFR. KOMA WILL LIKELY REMAIN AT VFR BUT
AN HOUR OR SO OF MVFR CANNOT BE RULED OUT IN SNOW FLURRIES. KLNK
SHOULD REMAIN VFR AS THIS BAND OF SNOW SHIFTS MORE EAST RATHER
THAN SOUTH. LIGHT NORTH WINDS WILL BECOME NORTHWEST THIS EVENING
AND GUST UP TOWARD 20-25 KTS THROUGH THE OVERNIGHT AND INTO MONDAY
MORNING.

KERNP MINS TONIGHT TO BE CLOSER TO RAW MODEL 
GUIDANCE.  EVEN SO...WIND CHILLS IN THE EXTREME NORTHEAST ARE 
PROGGED TO DANCE AROUND THAT -20F MARK FOR SEVERAL HOURS IN THE LATE 
OVERNIGHT/EARLY MORNING HOURS...AND WILL ISSUE A WIND CHILL ADVISORY 
FOR THOSE FEW COUNTIES FROM 09-16Z.

HAVE CONTINUED HIGHER CLOUD TREND INTO TOMORROW AND TOMORROW NIGHT 
AS NORTHWESTERLY FLOW REMAINS IN PLACE. HAVE NUDGED DOWN MAX TEMPS 
ON MONDAY AND NUDGED UP ON MONDAY NIGHT TO REFLECT TREND TOWARD 
HIGHER CLOUDS /NOT TO MENTION TO COMPETE WITH WARMER MIN TEMP 
GUIDANCE THAT HAS BEEN CLOSER TO VERIFICATION LATELY/. ANOTHER 
RIPPLE IN THE UPPER-LEVEL FLOW IS PROGGED TO STREAM ACROSS EASTERN 
NEB ON MONDAY EVENING THROUGH TUESDAY MORNING. DO THINK THAT THIS 
WAVE IS LACKING IN THE KIND OF MID-LEVEL FRONTOGENESIS THAT OCCURRED 
TODAY AND ALLOWED SLIGHT MEASURABLE SNOW TO REACH NORTHERN AND 
NORTHEASTERN FRINGES OF THE CWA...BUT FLURRIES ARE CERTAINLY 
POSSIBLE. HELD ONTO A SMALL AREA OF SLIGHT CHANCE POPS ON TUESDAY 
MORNING WHEN THE BEST LIFT MOVES OVERHEAD...BUT CONFIDENCE IS PRETTY 
LOW AS GUIDANCE IS MOSTLY TRENDING DRIER.

WEATHER SHOULD TREND PRETTY QUICKLY TOWARD THE MILDER SIDE STARTING 
ON TUESDAY AS WARM AIR ADVECTION GETS UNDERWAY.  HAVE NUDGED MAX 
TEMPS UPWARD TUESDAY THROUGH WEDNESDAY...WITH READINGS BACK INTO THE 
40S IN THE SOUTHERN CWA ON WEDNESDAY.

MAYES

LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
EARLY IN THE PERIOD...THE NEXT SURGE OF COLD AIR WILL BE MOVING INTO 
THE REGION AS THE NEXT SHORT WAVE MOVES THROUGH THE NORTHERN CONUS. 
THUS...TEMPERATURES WILL BE HEADED BACK DOWN THROUGH FRIDAY AS COLD 
HIGH PRESSURE SETTLES ACROSS THE REGION. TRENDED TEMPERATURES MORE 
IN LINE WITH THE COLDER HPC GUIDANCE EARLY IN THE PERIOD VERSUS 
REGIONAL MODEL BLENDS/CONSENSUS. WOULD ALSO NOT BE SURPRISED TO SEE 
A FEW FLURRIES NORTHEAST NEBRASKA AND WESTERN IOWA THURSDAY 
AFTERNOON AND ESPECIALLY THURSDAY NIGHT AS H85 TEMPS REMAIN IN THE 
DENDRITIC RANGE.  WILL HOLD OF THAT FOR NOW WITH CONSIDERATION TO 
ADD LATER ON. FRIDAY WILL PROBABLY BE THE COLDEST DAY THROUGH THE 
EXTENDED WITH HIGHS IN THE MID TEENS TO MID 20S. FOR SATURDAY/SUNDAY 
THE MODELS DIVERGE ON SOLUTIONS REGARDING AMOUNT OF WARMING. ECMWF 
MAINTAINS A SHARPER RIDGE...WITH WARMER AIR SLOWER TO RETURN... 
WHEREAS GFS HAS MORE OF A FLAT RIDGE...BECOMING ZONAL QUICKER 
ALLOWING WARMER TEMPS TO FILTER BACK QUICKER.  WILL OPT FOR MODEL 
BLENDS DURING LATTER PORTION OF THE FORECAST...WITH TEMPS BACK 
TOWARD THE LOWER/MID 40S BY SUNDAY. 

DEWALD

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WIND CHILL ADVISORY FROM 3 AM TO 10 AM CST MONDAY FOR NEZ012-015-
     018.

IA...WIND CHILL ADVISORY FROM 3 AM TO 10 AM CST MONDAY FOR IAZ043.

&&

$$