National Weather Service Raw Text Product

660 
FXUS63 KOAX 021757
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
1157 AM CST SAT FEB 2 2013

.UPDATE...
MORNING UPDATE TO ADD FLURRIES FARTHER WEST AND INCREASE POPS IN
WRN IOWA FOR TODAY AND REFINE CLOUDS...TEMPS AND WINDS.

&&

.DISCUSSION...
WARM AIR ADVECTION COMBINED WITH FAST MOVING NORTHWEST TO
SOUTHEAST FLOW RESULTING IN A QUICK SHOT OF LIGHT SNOW AND
FLURRIES. WSR-88D RADAR SHOWING SOME LIGHT SNOW AND FLURRIES
MOVING THROUGH PARTS OF EASTERN NEBRASKA AND WESTERN IOWA. A CALL
TO UTE IN MONONA COUNTY AND THEY HAD A DUSTING WITH THE SNOW THAT
JUST MOVED THRU.  ADJUSTED TEMPERATURES TO REFLECT WARMING INTO
THE 40S FOR PARTS OF FORECAST AREA TOWARD COLUMBUS AND EASTERN
AREAS HOLDING IN THE 30S.

&&

.AVIATION...
18Z TAFS FOR KOMA...KOFK...KLNK
MVFR CIGS ARE BEING REPORTED AT KOFK/KOMA/KLNK WITH KLNK ON THE
WRN EDGE. WARM AIR ADVECTION IS OCCURRING AHEAD OF THE NEXT
CLIPPER TYPE. AN AREA OF LIGHT SNOW AND FLURRIES PUSHED THRU KOFK
AND IS HEADING TOWARD KOMA. REPORTS HAVE BEEN SPARSE...BUT DID
DROP CIGS AND VSBYS WITH THE SNOW AT KOMA EARLY IN THE TAF PERIOD.
THE BULK OF THE SNOW WILL BE EAST AND NORTH OF THE TAF
SITES...WHERE THE COLD AIR IS DEEPER. CONDITIONS SHOULD IMPROVE TO
VFR AFTER 21Z AT KOFK/KLNK AND AFTER 00Z AT KOMA. VARIABLE WINDS
AHEAD OF THE WINDSHIFT TO THE NORTHWEST. KOFK SHOULD SWITCH TO THE
WEST AND NORTHWEST FIRST AND INCREASE TO AOA 15KTS WITH STRONGER
GUSTS. KOMA AND KLNK ARE MORE DELAYED WITH THE WIND SHIFT TO AFTER
02Z. DID INCLUDE LOW LEVEL WIND SHEAR WITH H9 NORTHWEST WINDS
INCREASING TO 40 TO 45KTS AFT 21Z AT KOFK AND STARTING 00-02Z AT
KOMA AND KLNK.

&&

.PREV DISCUSSION... /ISSUED 326 AM CST SAT FEB 2 2013/ 

DISCUSSION...
MESSY PATTERN CONTINUES TODAY...WITH POTENTIAL FOR LIGHT 
PRECIPITATION.  SUBJECTIVE 00Z UPPER AIR ANALYSIS INDICATES 
CONTINUED NORTHWEST UPPER-LEVEL FLOW ACROSS THE CENTRAL 
PLAINS...WITH 500MB HEIGHT FALLS UP TO 30-40M AHEAD OF A WEAK 
SHORTWAVE IN WY/CO.  HEIGHTS WERE RISING IN THE EASTERN US AS 
PATTERN REBOUNDS FROM DEEPER/COLDER TROUGHING.  TROUGH AT 850MB WAS 
APPROACHING EASTERN NEBRASKA AT 00Z...EXTENDING FROM CENTRAL MN 
THROUGH CENTRAL NEB TOWARD EASTERN CO.  850MB TEMPERATURES AT KOMA 
HAD RETURNED TO ABOVE-0C READINGS AS COLDEST AIR SHIFTS NORTHEAST.

MAIN FORECAST CONCERNS ARE LIGHT PRECIP POTENTIAL IN THE 
NORTHEASTERN CWA TODAY...ANOTHER SLIGHT CHANCE IN THE SOUTHEAST ON 
WEDNESDAY NIGHT...AND POTENTIAL WEEKEND SYSTEM LATE IN THE FORECAST. 
ISENTROPIC LIFT WILL GET GOING BY MIDDAY...FOCUSING ALONG AND EAST 
OF THE MISSOURI RIVER...AS A SHORTWAVE DIVES OUT OF SD IN THE 
NORTHWESTERLY FLOW.  DOES SEEM TO BE ENOUGH LIFT AND SUSTAINED LONG 
ENOUGH TO PRODUCE LIGHT PRECIP THIS AFTERNOON...MAINLY IN NORTHWEST 
TO WEST CENTRAL IOWA AND EASTWARD.  HAVE ADDED POPS IN THE NORTHEAST 
CORNER OF THE CWA THIS AFTERNOON...WITH RAIN/SNOW MIX THE MOST 
LIKELY PRECIP TYPE BUT WITH SOME LOW CONFIDENCE THERE ABOUT
WHETHER IT WILL BE MIXED OR ALL SNOW. AMOUNTS SHOULD BE LIGHT AS
BEST FORCING PASSES TO THE EAST.

FROM SUNDAY THROUGH WEDNESDAY...SHOULD SEE MODERATING TEMPS AND
FAIR WEATHER ACROSS THE AREA AS UPPER-LEVEL PATTERN BECOMES ZONAL
AND THEN FLOW TURNS A LITTLE MORE WEST-SOUTHWESTERLY. HAVE HELD
BACK DAILY MAX TEMPS OVER THE SNOWIEST AREAS...BUT SEVERAL DAYS OF
MILD TEMPS SHOULD ERODE SNOWPACK. NEXT CHANCE FOR PRECIP LOOKS
LIKE WEDNESDAY NIGHT IN THE FAR SOUTHEAST CWA...AS A WAVE EJECTING
THROUGH THE WEST-SOUTHWESTERLY FLOW KICKS UP SOME PRECIPITATION.
CWA IS ON THE EDGE OF THE CURRENT PROGGED STORM TRACK...BUT HAVE
INCLUDED A SLIGHT CHANCE MENTION FOR SNOW FOR NOW.

MILD TEMPERATURES SHOULD CONTINUE INTO THE WEEKEND...WITH A 
POTENTIAL STORM SYSTEM DEVELOPING FOR FRIDAY NIGHT THROUGH AT LEAST 
SATURDAY. GFS/ECMWF ARE FAIRLY CONSISTENT IN PRODUCING PRECIPITATION 
OVER THE CWA FOR SEVERAL PERIODS AS A CLOSED LOW EJECTS ACROSS THE 
PLAINS.  AS EXPECTED AT 7 DAYS OUT...THERE ARE DIFFERENCES IN TRACK 
AND TIMING OF THE SYSTEM AMONG MODELS AND RUN-TO-RUN...WITH 
IMPLICATIONS FOR PRECIPITATION TYPE/TIMING.  FOR NOW...HAVE INSERTED 
A CHANCE POP INTO SATURDAY WITH RAIN/SNOW OR RAIN MENTION.

MAYES

&&

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

$$

ZAPOTOCNY