Ice Storm in Kansas, February 21, 2010

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DODGE CITY KS
247 AM CST SUN FEB 21 2010

.DISCUSSION...

DAYS 1-2...

RADAR TRENDS THIS MORNING INDICATED THAT THE STEADIER AND HEAVIER
PCPN WAS OCCURRING WHERE THE BETTER 85H WAA AND 85-7H FGEN WAS
PROGGED TO BE AT 6Z. PHONE CALLS TO THESE AREAS SUGGESTED MAINLY
SNOW BUT SOME SLEET WAS STILL BEING REPORTED IN A FEW SPOTS IN
STAFFORD, PRATT AND BARBER COUNTIES. BASED ON THE NAM AND GFS THIS
PCPN IS EXPECTED TO CONTINUE IN OUR ERN CWA THROUGH 12Z AND THEN
BEGIN TO TAPER OFF. AS A RESULT WILL LEAVE ALL ADVISORIES AND
WARNINGS GOING EAST OF DDC WHERE THE HEAVIER PCPN WILL BE BASED ON
RADAR AS OF 9Z BUT MAY TWEAK THE EXPIRATION TIME SINCE THE BETTER
LIFT IS PROGGED TO SHIFT EAST OF THE AREA BY 18Z. ELSEWHERE WILL
GO AHEAD AND CANCEL ALL ADVISORIES EVEN THOUGH AM NOT ABLE TO
COMPLETELY RULE OUT A SOME LIGHT SNOW LATER TODAY AS OUR 5H TROF
APPROACHES THE AREA FROM THE SW. IF ANYTHING DOES DEVELOP LATER
TODAY...NO ACCUMULATION IS EXPECTED.

SURFACE HIGH WILL START TO SETTLE INTO THE CNTL PLAINS EARLY
SUNDAY NIGHT AS A NORTHERN BRANCH S/W TROF DROPS SOUTH TOWARDS
WESTERN KS. WEST OF THE LLVL RIDGE AXIS MOISTURE AND UPSLOPE FLOW
REMAINS PRESENT SO AS OUR NEXT NORTHERN BRANCH WAVE APPROACHES AM
NOT ABLE TO COMPLETELY RULE OUT SOME LIGHT PCPN REDEVELOPING LATER
TONIGHT IN OUR FAR WESTERN CWA. WILL THEREFORE RETAIN SMALL POPS
IN OUR WEST SUNDAY NIGHT INTO MONDAY.

BY LATE MONDAY BOTH THE NAM AND GFS MOVES OUR S/W TROF SOUTH OF
THE AREA WHICH WILL BRING AN END TO ALL PCPN CHCS AND POSSIBLY
BRING SOME CLEARING TO OUR NRN CWA MONDAY NIGHT. HOW MUCH CLEARING
REMAINS UNCLEAR BUT WITH LIGHT WINDS ANY CLEARING THAT DOES DEVELOP IN
THE NORTH MONDAY NIGHT COULD YIELD SOME COLD TEMPS TUESDAY
MORNING.

DAYS 3-7...

MEDIUM RANGE MODELS ARE IN FAIR AGREEMENT INDICATING AN UPPER LEVEL
TROUGH OF LOW PRESSURE TRANSITIONING EAST ACROSS TEXAS TUESDAY
STAYING CLEAR OF SOUTHWEST KANSAS. MEANWHILE, UPPER LEVEL RIDGING
ACROSS THE EXTREME WESTERN CONUS, WILL MOVE EAST ACROSS THE ROCKIES
TUESDAY NIGHT AND INTO THE CENTRAL PLAINS WEDNESDAY BEFORE BEGINNING
TO BREAK DOWN. THIS WILL RESULT IN FAIRLY DRY CONDITIONS ACROSS
WESTERN KANSAS THROUGH THURSDAY. TEMPERATURES ARE EXPECTED TO BE
WELL BELOW NORMAL TO BEGIN THE PERIOD TUESDAY. A LOW LEVEL
NORTHERLY FLOW WILL BE IN PLACE ACROSS WESTERN KANSAS AS A RESULT
OF THE UPPER LEVEL WAVE PASSING JUST TO OUR SOUTH ALLOWING COOLER
AIR TO CONTINUE FILTERING INTO THE AREA. THE GFS AND ECMWF SHOW H85
TEMPERATURES RANGING FROM FROM AROUND 5C BELOW TO 7C BELOW ACROSS
EASTERN PORTIONS OF THE CWA TO NEAR 0C ALONG THE COLORADO BORDER.
AS A RESULT, HIGHS ARE EXPECTED PRIMARILY IN THE 30S(F) TUESDAY.
LEE SIDE TROUGHING WILL DEVELOP WEDNESDAY AS UPPER LEVEL RIDGING
APPROACHES FROM THE WEST RESULTING IN AN EXPECTED WARMING TREND
THROUGH MID WEEK. PLAN NO SIGNIFICANT CHANGES TO TEMPERATURES.

&&

.AVIATION...

AREAS OF LINGERING SNOW FALL WILL BE POSSIBLE THROUGH MID DAY AS A
STRONG UPPER LEVEL SYSTEM MOVING EAST ACROSS KANSAS AND OKLAHOMA
EXITS THE REGION BY THIS AFTERNOON. HOWEVER, MVFR/IFR CONDITIONS
WILL REMAIN POSSIBLE THROUGH LATE THIS EVENING DUE TO LOW LEVEL
STRATUS AND POSSIBLE AREAS OF BLOWING SNOW AS WINDS INCREASE OUT OF
THE NORTH 15 TO 25 MPH WITH GUSTS UP TO 35 MPH BY LATE THIS MORNING.

&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  27  16  28  13 /  30  10  10  10
GCK  27  16  29  11 /  20  20  10  10
EHA  29  18  30  14 /  20  20  20  20
LBL  30  19  30  14 /  20  20  20  20
HYS  27  14  27  10 /  60  10  10  10
P28  32  21  31  18 /  70  10  10  10

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR KSZ030-
031-044-045-077-078-080-081-087>090.

WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR KSZ046-
064>066-079.

&&

FN18/32/32

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE DODGE CITY KS
310 PM CST SAT FEB 20 2010

KSZ030-031-043>046-061>066-074>081-084>090-212115-
TREGO-ELLIS-SCOTT-LANE-NESS-RUSH-HAMILTON-KEARNY-FINNEY-HODGEMAN-
PAWNEE-STAFFORD-STANTON-GRANT-HASKELL-GRAY-FORD-EDWARDS-KIOWA-
PRATT-MORTON-STEVENS-SEWARD-MEADE-CLARK-COMANCHE-BARBER-
310 PM CST SAT FEB 20 2010 /210 PM MST SAT FEB 20 2010/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL...SOUTH
CENTRAL...SOUTHWEST AND WEST CENTRAL KANSAS.

.DAY ONE...THIS AFTERNOON AND TONIGHT

A WINTER STORM SYSTEM WILL MOVE FROM THE DESERT SOUTHWEST AND INTO
THE PLAINS LATER TONIGHT AND SUNDAY. THIS SYSTEM WILL BRING
WIDESPREAD SNOW TO SOUTHWEST AND SOUTH CENTRAL KANSAS WITH SNOW
AMOUNTS GENERALLY FROM 2 TO 5 INCHES...WITH THE HIGHEST AMOUNTS
FROM SAINT JOHN TO LARNED...LACROSSE...AND HAYS. AREAS OF FREEZING
DRIZZLE WILL BE POSSIBLE AHEAD OF THIS STORM SYSTEM TONIGHT THEN
TRANSITIONING TO MOSTLY SNOW AROUND OR AFTER MIDNIGHT. SOME ICE
ACCUMULATION OF LESS THAN ONE QUARTER OF AN INCH IS POSSIBLE SOUTHEAST
OF A LINE FROM LARNED TO DODGE CITY AND LIBERAL BEFORE TRANSITIONING
TO SNOW ON SUNDAY MORNING.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THE PROBABILITY OF WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT. HOWEVER,
ANY SNOW REPORTS WOULD BE APPRECIATED.

&&

FOR MORE INFORMATION VISIT OUR WEBPAGE AT HTTP://WEATHER.GOV/DDC

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