FXUS63 KICT 222101
AFDICT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WICHITA KS
300 PM CST TUE DEC 22 2009
.DISCUSSION...
MAIN FORECAST CONCERN IS OBVIOUSLY THE WINTER STORM TO IMPACT THE
CENTRAL PLAINS TONIGHT THROUGH FRI:
SYNOPSIS:
WATER VAPOR COMBINED WITH POTENTIAL VORTICITY ANALYSIS SHOWS A FEW
PIECES OF ENERGY ALONG THE WEST COAST. ONE IS CENTERED OVER
SOUTHERN CA/NORTHERN BAJA WITH ANOTHER ONE EXTENDING FROM OREGON
INTO WESTERN NV. LAST BUT NOT LEAST ANOTHER CHUNK IS TRACKING SOUTH
ACROSS BRITISH COLUMBIA. SURFACE LOW PRESSURE IS NOW STARTING TO
STRENGTHEN OVER THE TX PANHANDLE WITH THE APPROACHING SHORTWAVE.
MEANWHILE A STRONG WARM FRONT IS SITUATED GENERALLY ALONG THE KS
TURNPIKE DOWN INTO WESTERN OK.
FORECAST MODELS HAVE MADE SOME CHANGES TO THIS SYSTEM NOW THAT IT IS
ON SHORE AND THEREFORE WILL ADJUST HEADLINES TO BETTER REPRESENT
LATEST TRENDS.
TONIGHT:
COMPLICATED FORECAST FOR PORTIONS OF CENTRAL KS FOR TONIGHT...WITH
SOME SHORT TERM MODEL DIFFERENCES ON HOW WARM THE LAYER JUST OFF THE
SFC WILL GET AND OF COURSE IMPACTS ON PRECIP TYPE AS THIS SHALLOW
COLD AIR HOVERS NEAR FREEZING. LATEST 12Z/NAM/WRF IS DOING A DECENT
JOB WITH CURRENT SFC TEMPS...WITH TEMPS IN CENTRAL KS HOVERING JUST
ABOVE FREEZING AS COLDER AIR AND STRATUS AND PATCHY FOG OOZES INTO
THIS AREA. EXPECT THE COLDER AIR TO COME TO A HALT SOMEWHERE BETWEEN
KHUT AND KICT AS THE AFTERNOON INTO THE EVENING CONTINUES AND WARM
ADVECTION GETS UNDER WAY JUST OFF THE SURFACE.
ACROSS SOUTHERN KS...WILL SEE DRIZZLE TURN INTO RAIN SHOWERS TONIGHT
AS STRONG WARM ADVECTION KEEPS TEMPS ABOVE FREEZING. ELEVATED
INSTABILITY AND STEEP LAPSE RATES EARLY ON WED...MAY ALSO LEAD TO
SOME SHOWERS AND EMBEDDED THUNDERSTORMS FOR WED MORNING.
DEEPER SATURATION WILL LEAD TO THIS DRIZZLE CHANGING OVER TO A MIX
OF RAIN AND FREEZING RAIN AS THE OVERNIGHT PROGRESSES INTO WED
MORNING ACROSS CENTRAL KS. SURFACE TEMPS ARE EXPECTED TO REMAIN NEAR
FREEZING IN CENTRAL KS...SO ANY PRECIP THAT FALLS WILL CERTAINLY
BEGIN TO CAUSE ICING CONCERNS ON ELEVATED SURFACES. NOT AS CONCERNED
ABOUT TREATED ROADS AS LATENT HEAT RELEASE CAUSED BY THE RAIN WILL
HELP TEMPS TO RISE A DEGREE OR TWO...WHICH WILL KEEP ROADS FROM
FREEZING UP...BUT CERTAINLY CONCERNED ABOUT TREES AND POWER LINES IN
CENTRAL KS EARLY ON WED WITH A TENTH TO A QUARTER OF AN INCH OF ICE
ACCUMULATION POSSIBLE.
WARM AIR OVER THE TOP OF THIS SHALLOW COLD AIR MIGHT ACTUALLY CHANGE
THE FREEZING RAIN OVER TO A STEADY SLEET SHOWER ALONG INTERSTATE 70
TOWARD DAYBREAK. SO WILL CERTAINLY SEE A MIXED BAG OF WINTER PRECIP
IN CENTRAL KS EARLY ON WED.
WED-FRI:
THROUGH THIS TIME FRAME THE MODELS HAVE TRENDED FURTHER NORTH AND
EAST WITH THE BETTER DYNAMICS AS THIS SYSTEM COMES OUT IN TWO
CHUNKS. WHILE THE PREVIOUS RUNS HAD THE BEST LIFT EXTENDING THROUGH
CENTRAL KS ON WED-WED NIGHT...THE LATEST RUNS HAVE TAKEN THIS LIFT
FURTHER NORTH. BY 18Z WED THE FIRST VORT LOBE WILL EXTEND FROM
CENTRAL OK DOWN INTO NORTHERN BAJA WITH WITH THE SECOND PIECE
TRACKING SOUTH ACROSS MT. DURING THE DAY WED FEEL THAT CENTRAL KS
WILL GRADUALLY TRANSITION TO ALL SNOW BUT AM CONFIDENT THEY WILL SEE
SOME SLEET MIXED IN BEFORE 18Z. AT THE SAME TIME THERE IS MODEL
CONSENSUS THAT A DRY SLOT WILL MOVE-IN FROM THE SOUTHWEST AND WILL
OVERSPREAD MUCH OF SE AND SOUTH CENTRAL KS KEEPING THE PRECIP IN
LIQUID FORM. THROUGH THE DAY WED FEEL CONFIDENT THAT CENTRAL KS WILL
HAVE THE BEST SHOT TO EXPERIENCE HAZARDOUS WINTER WX AND WILL THUS
EXTEND THE CURRENT WINTER WEATHER ADVISORY OUT THROUGH 00Z THU.
RATHER THAN A COMPACT SURFACE LOW LIKE PREVIOUS MODEL RUNS
HAD...THEY NOW ALL AGREE ON A MORE ELONGATED SURFACE TROUGH WED
NIGHT EXTENDING THROUGH THE ARKLATEX REGION INTO NORTHEAST KS. THIS
LATEST TREND KEEPS THE BETTER LIFT NORTH OF OUR FORECAST AREA. MUCH
COLDER AIR AND STRONG NW WINDS WILL ALSO START TO SPILL INTO THE
AREA FROM THE NW WED NIGHT INTO THU MORNING. HOWEVER THE LATEST
MODEL TRENDS HAVE BEEN TO BACK OFF ON THE WIND SPEEDS. THEREFORE
FEEL CONFIDENT ENOUGH AT THIS POINT TO CHANGE THE BLIZZARD WATCH
OVER TO A WINTER STORM WATCH AND ALSO TO CANCEL THE SOUTHERN
COUNTIES OUT OF IT. BY THU AFTERNOON ANY PRECIP WILL HAVE CHANGED
OVER TO SNOW AS THE COLDER AIR CONTINUES TO SPILL-IN FROM THE
NORTHWEST AS YET ANOTHER PIECE OF ENERGY SWINGS OUT OF EASTERN OK
AND INTO SOUTHERN MO. THIS WILL ALLOW A SECONDARY SURFACE LOW TO
DEVELOP OVER CENTRAL MO WHICH MAY BRING ANOTHER ROUND OF WINTER
PRECIP TO EASTERN KS/MUCH OF MO. THE THU AFTERNOON-THU NIGHT TIME
FRAME IS PERIOD THAT WILL NEED TO BE WATCHED CLOSELY BECAUSE IF THE
MODELS CONTINUE THIS TREND OF A SECONDARY LOW FORMING...THEN
ADDITIONAL HEADLINES WOULD BE NEEDED FURTHER EAST.
ON FRI THIS SYSTEM IS EXPECTED TO CONTINUE TO DEEPEN AS THE SURFACE
LOW LIFTS NORTH AND SHOULD BE SITUATED OVER WEST-CENTRAL IA BY 12Z
FRI. THIS WOULD ALLOW THE STRONG NW WINDS TO REMAIN OVER THE AREA
WITH SOME LIGHT SNOW POSSIBLE...ESPECIALLY OVER CENTRAL KS. HOWEVER
FOR FRI IT APPEARS THE BETTER HEAVY SNOWFALL CHANCES WILL BE OVER
EASTERN NE AND NORTHEAST KS.
EXTENDED: SATURDAY THROUGH TUESDAY
MAIN CONCERN FOR THE EXTENDED PERIODS IS TEMPERATURES AND THE CHANCE
OF A SYSTEM AT THE END OF THE TERM. CURRENT MODELS HAVE TRENDED THIS
UPPER LEVEL LOW TO SLOWLY MOVE OUT OF THE CONUS BY TUESDAY. THIS
WILL GIVE US STRONG NW FLOW AND COLD TEMPERATURES. OVER THE WEEKEND
HIGH PRESSURE WILL MOVE INTO THE AREA WARMING TEMPERATURES SLIGHTLY.
BOTH MODELS ALSO ARE SHOWING ANOTHER DIGGING TROUGH ACROSS THE
PACIFIC COAST WHICH WILL BRING IN ANOTHER SYSTEM DURING THE MID-WEEK
NEXT WEEK. FOR NOW LEFT POPS OUT OF DAYS 6 AND 7 SINCE THE MODELS
ARE SO FAR OUT AND THERE IS LACK OF CONFIDENCE IN THEM. BECAUSE OF
THE COLDER AIR MASS THAT WILL BE IN PLACE HAVE TRENDED TEMPS
SLIGHTLY BELOW HPC.
KETCHAM/LAWSON/DUNTEN
&&
.AVIATION...18Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
A RATHER DIFFICULT AND COMPLICATED TAF FORECAST ACROSS THE AREA...
AS WEATHER CONDITIONS AT ALL TAF SITES WILL CONTINUE TO DETERIORATE
THROUGH THE PERIOD AS A WINTER STORM APPROACHES FROM THE SOUTHWEST.
CEILINGS IN CENTRAL KANSAS WILL REMAIN IN LIFR CATEGORY THROUGH MUCH
OF THE DAY TODAY...BUT THIS STRATUS DECK IS EXPECTED TO REMAIN NORTH
OF THE KICT/KCNU TAF SITES UNTIL THIS EVENING...WITH IFR CEILINGS
ACROSS SOUTHERN KS. MOISTURE AND LIFT WILL INCREASE TONIGHT ACROSS
THE AREA...WITH AREAS OF DRIZZLE AND FURTHER NORTH FREEZING DRIZZLE
DEVELOPING OVER CENTRAL KS WHILE DRIZZLE REMAINS MORE LIKELY ACROSS
SOUTHERN KS. THE DRIZZLE WILL EVENTUALLY CHANGEOVER TO RAIN IN
SOUTHERN KS AND FREEZING RAIN IN CENTRAL KS AS LIFT AND MOISTURE
DEEPENS. SOME CONCERN ABOUT AN EXTENDED PERIOD OF FREEZING RAIN
ACROSS CENTRAL KS EARLY ON WED...WHERE SHALLOW COLD AIR WILL KEEP
TEMPS BELOW FREEZING THE LONGEST. THIS WARM AIR OVER THE TOP OF THE
COLD AIR WILL ACTUALLY LEAD TO FREEZING RAIN CHANGING OVER TO A MIX
OF FREEZING RAIN AND SLEET BY 12Z/WED ACROSS CENTRAL KS.
FURTHER TO THE SOUTH...SOME ELEVATED INSTABILITY MAY ALSO LEAD TO
SOME EMBEDDED TSRA DEVELOPING NEAR THE KCNU AND KICT TAF SITES EARLY
ON WED AS WELL. SO HAVE INCLUDED THIS MENTION IN SOUTHERN KS.
WEATHER CONDITIONS AT MOST OF THE TAF SITES WILL LIKELY NOT IMPROVE
THROUGH THE NEXT COUPLE DAYS.
KETCHAM
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 37 42 27 31 / 80 90 70 90
HUTCHINSON 33 35 26 28 / 100 100 80 90
NEWTON 35 39 26 31 / 90 100 70 90
ELDORADO 41 45 29 33 / 90 90 70 90
WINFIELD-KWLD 46 48 30 34 / 80 90 70 80
RUSSELL 29 32 20 21 / 100 100 90 90
GREAT BEND 30 33 23 23 / 100 100 90 80
SALINA 31 34 24 25 / 100 100 90 90
MCPHERSON 33 36 25 28 / 100 100 80 90
COFFEYVILLE 49 57 37 41 / 90 80 90 90
CHANUTE 46 54 35 38 / 90 90 80 90
IOLA 45 52 34 38 / 90 90 80 90
PARSONS-KPPF 47 56 37 40 / 90 80 90 90
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM CST
WEDNESDAY FOR KSZ032-033-047>051-067.
WINTER STORM WATCH FROM WEDNESDAY EVENING THROUGH FRIDAY MORNING
FOR KSZ032-033-047>052-067.
&&
$$
