Winter Weather and Sleet in Kansas, February 20 to 21, 2008

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WICHITA KS
916 PM CST WED FEB 20 2008

.UPDATE...
LATEST LAPS SOUNDING DATA SUPPORTS LIGHT FREEZING DRIZZLE AND
CALLS OUT TO SOUTHERN KANSAS CONFIRMED THE LIGHT FREEZING DRIZZLE
PRECIP ALONG WITH SOME LIGHT FREEZING DRIZZLE HERE AT THE OFFICE.
DEW POINT DEPRESSIONS ARE BECOMING SMALLER ACROSS THE AREA WHICH
MEANS THE DRIZZLE WILL BEGIN TO CAUSE SLICK SPOTS ON UNTREATED
ROADS...AND COLLECT ON WINDSHIELDS. WE ALSO COULD SEE SOME
FLURRIES OR LIGHT SNOW AT TIMES DUE TO SEEDER/FEEDER EFFECTS FROM
MID-LEVEL RETURNS ON RADAR AND VAD WINDS CLOSING UP THE DRY LAYER
GAP...BUT MAIN CONCERN WILL BE FREEZING DRIZZLE. WE WILL INSERT AREAS OF
LIGHT FREEZING DRIZZLE AND LIGHT SNOW AS A SECONDARY PRECIP TYPE.
DUE TO POSSIBLE SLICK SPOTS WILL PUSH UP THE ADVISORY TIMING FOR
THE FREEZING DRIZZLE. STILL LOOKS LIKE THE MORE PROBLEMATIC
PRECIP(SLEET OR FREEZING RAIN) WILL HIT SOUTHERN KANSAS DURING THE
MORNING HOURS...WHICH COULD BE VERY TROUBLE DURING THE MORNING COMMUTE.
SOME ISOLATED THUNDER WILL ALSO BE POSSIBLE IN MORNING ACROSS SOUTHERN
KANSAS GIVEN MUCAPES IN THE 850-300MB LAYER AROUND 100J/KG. THIS
WOULD INCREASE SLEET/ICE ACCUMULATIONS EVEN MORE AND LATEST NAM
MODEL IS HITTING US WITH HIGHER PRECIP AMOUNTS DUE TO STRONG LIFT
ALONG THE 850MB FRONT...WHICH WILL BE POSITIONED FROM NORTH CENTRAL
OKLAHOMA TOWARDS EMPORIA. THIS CORRIRDOR WILL HAVE TO BE WATCHED
CLOSELY.

JAKUB

&&

.PREV DISCUSSION... /ISSUED 544 PM CST WED FEB 20 2008/

AVIATION...
00Z TAF UPDATE...MVFR CEILINGS WILL GRADUALLY DEVELOP ACROSS
SOUTHERN KANSAS AND SPREAD NORTHWARD TO CENTRAL KANSAS TAF SITES
AROUND 09Z. PERIODS OF SLEET OR FREEZING RAIN WILL AFFECT SOUTHERN
KANSAS BEFORE SUNRISE AND CONTINUE TO THROUGH THE DAYTIME HOURS ON
THURSDAY. MEANWHILE...CENTRAL KANSAS TAF SITES COULD WITNESS SOME
LIGHT SNOW SHORTLY AFTER SUNRISE.

JAKUB

PREV DISCUSSION... /ISSUED 318 PM CST WED FEB 20 2008/

DISCUSSION...

MAIN FORECAST CHALLENGE CONTINUES TO DEAL WITH THE WINTER EVENT TO
IMPACT THE AREA LATE TONIGHT THROUGH EARLY FRI MORNING.

SYNOPSIS:
POLAR FRONT SWEPT THROUGH THE AREA AND IS NOW SITUATED GENERALLY
ALONG THE RED RIVER. IN THE UPPER LEVELS A SHORTWAVE IS APPROACHING
THE DESERT SOUTHWEST WITH 850MB PROFILERS OVER THE PLAINS RESPONDING
TO THIS APPROACHING WAVE BY FLIPPING AROUND TO THE SOUTHEAST.

TONIGHT-FRI NIGHT:
850MB-700 WARM ADVECTION WILL INCREASE DRASTICALLY TONIGHT IN
ADDITION TO ISENTROPIC LIFT ALONG THE 295-300K SURFACES. IN ADDITION
LIS FROM A PARCEL LIFTED FROM 800MB WILL GO NEGATIVE OVER SOUTH
CENTRAL AND SE KS LATE TONIGHT INTO THU MORNING WHICH MAY LEAD TO
SOME CONVECTIVE ELEMENTS. CONFIDENCE IS HIGH THAT PRECIP WILL MOVE
INTO THE SOUTHERN HALF OF THE AREA GENERALLY AFTER 3 AM. CURRENT
THINKING FOR PRECIP TYPE HASNT CHANGED TOO MUCH FROM YESTERDAYS
FORECAST. THE NAM IS STILL SLIGHTLY COOLER IN THE LOWER LAYERS WITH
THE GFS STARTING TO TREND COOLER. GIVEN THE ORIGINS OF THE AIRMASS
AFFECTING THE PLAINS AND THE FACT THAT THE NAM HAS BEEN HOLDING ITS
GROUND...WILL STICK CLOSER TO THE NAM FORECAST SOUNDINGS. CONFIDENCE
IS INCREASING THAT THE PRIMARY PRECIP TYPE FOR MUCH OF THIS EVENT
FOR SOUTH CENTRAL AND SE KS WILL BE IN THE FORM OF
SLEET...ESPECIALLY WITH SOME CONVECTIVE ELEMENTS FLOATING AROUND THU
MORNING. EVEN THOUGH ICE WILL LIKELY NOT BE INTRODUCED INTO THE TOP
OF THE SOUNDINGS...LOW LEVEL TEMPS NEAR -10C WILL ALLOW PARTIAL
FREEZING OF PRECIP AS IT FALLS RESULTING IN SLEET. THIS ALSO AGREES
WITH THE LAST COUPLE RUNS OF THE SREF WHICH GIVES IP AS THE MAIN
PRECIP TYPE. OBVIOUSLY WITH TEMPS SUB FREEZING...ANY LIQUID THAT
DOES FALL WILL FREEZE ON CONTACT.

THE GOOD NEWS IS THAT THE SLEET WILL CUT DOWN ON THE AMOUNT OF
FREEZING RAIN AND A SIGNIFICANT ICING. THEREFORE WILL KEEP WINTER
WEATHER ADVISORY AND WILL EXPAND A ROW OF COUNTIES NORTH AND
EXTENDING OUT TIL 06Z FRI. THE ACTUAL SHORTWAVE WILL SLIDE ACROSS
NORTH TX/OK THU EVENING PLACING THE AREA IN THE WRAP AROUND REGION
OF THIS SYSTEM WITH THE NAM EVEN SHOWING A MINOR TROWAL. WITH AN
INCREASE IN MID LEVEL SATURATION THE PRIMARY PRECIP TYPE AFTER DARK
ON THU EVENING WILL BE SNOW.

SAT-SUN:
THE ACTIVE PATTERN WILL CONTINUE THROUGH THESE PERIODS AS ANOTHER
FAST MOVING SHORTWAVE MOVES OUT OF THE ROCKIES AND INTO THE PLAINS
ON SAT. BOTH THE GFS AND ECM HAVE BEEN CONSISTENT WITH THE TRACK OF
THIS SYSTEM AND ALSO WITH MUCH OF THE AREA BEING PLACED IN THE WRAP
AROUND REGION. THEREFORE WENT AHEAD AND INCREASE PRECIP CHANCES ON
SAT. ANY SNOW THAT DOES FALL SAT WILL QUICKLY MELT WITH ABOVE NORMAL
TEMPS STILL LOOKING LIKELY FOR SUN AS THE UPPER FLOW FLATTENS OUT.

MON-WED:
MEDIUM RANGE MODELS STILL AGREE ON BRINGING YET ANOTHER FAST MOVING
PIECE OF ENERGY INTO THE PLAINS ON MON. DID INSERT SOME PRECIP
CHANCES ALONG THE NE FRINGES OF THE FORECAST AREA FOR MON AND MON
NIGHT WITH LOW CONFIDENCE IN HOW THIS PRECIP EVENT WILL PAN OUT.
HOWEVER HAVE MUCH HIGHER CONFIDENCE THAT ANOTHER COLD FRONT WILL
SWEEP THROUGH THE AREA MON NIGHT PROVIDING MUCH BELOW NORMAL TEMPS
FOR TUE.

LAWSON

&&

.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT    16  26  23  36 /  40  80  50  20
HUTCHINSON      14  26  21  36 /  30  60  50  20
NEWTON          14  26  22  36 /  40  70  50  20
ELDORADO        16  27  22  35 /  40  80  60  30
WINFIELD-KWLD   19  28  24  36 /  50  90  70  30
RUSSELL         12  26  18  38 /  20  40  40  10
GREAT BEND      13  26  18  38 /  20  50  40  10
SALINA          13  26  18  36 /  20  60  50  20
MCPHERSON       14  25  21  36 /  30  60  50  20
COFFEYVILLE     19  27  24  34 /  60 100  70  30
CHANUTE         17  27  22  32 /  50 100  70  30
IOLA            16  27  22  32 /  40 100  70  30
PARSONS-KPPF    18  27  23  33 /  60 100  70  30

&&

.ICT WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO MIDNIGHT CST
THURSDAY NIGHT FOR KSZ052-053-067>072-082-083-091>096-098>100.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE WICHITA KS
356 PM CST WED FEB 20 2008

KSZ032-033-047>053-067>072-082-083-091>096-098>100-211745-
RUSSELL-LINCOLN-BARTON-ELLSWORTH-SALINE-RICE-MCPHERSON-MARION-CHASE-
RENO-HARVEY-BUTLER-GREENWOOD-WOODSON-ALLEN-KINGMAN-SEDGWICK-HARPER-
SUMNER-COWLEY-ELK-WILSON-NEOSHO-CHAUTAUQUA-MONTGOMERY-LABETTE-
356 PM CST WED FEB 20 2008

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

.DAY ONE...TONIGHT

WITH COLD AIR IN PLACE...MOISTURE LADEN AIR OVERRIDING THE FREEZING
AIR BENEATH WILL BRING A POTENTIAL FOR FREEZING RAIN AND SLEET
ACROSS SOUTHERN KANSAS BEGINNING AFTER MIDNIGHT. SEE THE LATEST
WINTER WEATHER ADVISORY FOR MORE DETAILS.

WIND CHILLS BETWEEN 0 AND MINUS 5 WILL AFFECT CENTRAL KANSAS LATE
TONIGHT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

FREEZING RAIN...SLEET AND LIGHT SNOW WILL CONTINUE ON THURSDAY INTO
THURSDAY EVENING ACROSS SOUTHERN AND PORTIONS OF CENTRAL KANSAS. SEE
THE LATEST WINTER WEATHER ADVISORY FOR MORE DETAILS.

WIND CHILLS BETWEEN 0 AND MINUS 5 WILL AFFECT CENTRAL KANSAS EARLY
THURSDAY MORNING.

ANOTHER CHANCE OF LIGHT SNOW IS ALSO POSSIBLE ON FRIDAY AND AGAIN
SATURDAY.  CURRENT INDICATIONS SUGGEST THAT ACCUMULATIONS WILL BE
LITTLE IF ANY.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTER ACTIVATION IS NOT ANTICIPATED.

&&

FOR A GRAPHICAL VERSION OF THIS INFORMATION...SEE OUR
WEBPAGE AT (LOWERCASE) HTTP://WEATHER.GOV/WICHITA/HWO/HWO.PHP

KED/KETCHAM/LAWSON