FXUS63 KICT 230525
AFDICT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WICHITA KS
1125 PM CST TUE DEC 22 2009
.UPDATE...
OVERNIGHT:
WITH TSRA DEVELOPING OVER NE OK & SE KS HAVE MOVED STARTING TIME OF
CONVECTION UP 3 HOURS. REMAINDER OF FORECAST KEPT INTACT.
&&
.AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
ONLY CHANGES TO 00Z ISSUANCE WERE TO INTRODUCE TSRA/VCTS TO KCNU &
KICT TERMINALS RESPECTIVELY. OTHERWISE ALL 5 TERMINALS TO REMAIN
SHROUDED IN LIFR CIGS & VSBYS FOR REST OF THE NIGHT AS -FZDZ/-FZRA
INCREASING IN COVERAGE OVER CNTRL KS. WITH 850-MB WARM ADVECTION
INCREASING THROUGHOUT THE NIGHT & WED MORNING EXPECT ALL TERMINALS
TO REMAIN IFR STRATIFIED THROUGHOUT THE DAY WED.
&&
.PREV DISCUSSION... /ISSUED 737 PM CST TUE DEC 22 2009/
UPDATE...
TONIGHT:
WITH VSBYS ~1/2SM CONTINUING TO BE REPORTED IN RUSSELL COUNTY HAVE
DECIDED TO ISSUE AN UPDATE TO ADD AREAS OF FOG TO PRIMARILY CNTRL
KS FOR THE REST OF THE NIGHT. REMAINDER OF INHERITED FORECAST KEPT
INTACT FOR TIME BEING.
PREV DISCUSSION... /ISSUED 617 PM CST TUE DEC 22 2009/
AVIATION...00Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
ALL OF CNTRL & MOST OF SC KS TO REMAIN SHROUDED IN LIFR STRATUS W/
VSBYS FREQUENTLY 1-3SM THROUGHOUT THE NIGHT. WHILE KICT & KCNU ARE
IN MVFR STATUS EARLY THIS EVENING...BOTH TERMINALS WILL EXPERIENCE
CIGS LOWERING INTO IFR CATEGORY ~23/03Z & REMAIN AS SUCH THROUGHOUT
THE NIGHT AS INTENSE SFC LOW MOVES FROM ERN NM ACROSS W TX TONIGHT.
TEMPS BEING MONITORED CLOSELY...ESPECIALLY IN CNTRL KS WHERE TEMPS
ARE HOVERING ~32F. WITH SATURATED AIRMASS FAIRLY SHALLOW (~5,000FT)
ANY PRECIPITATION THAT OCCURS LIKELY TO BE -DZ/-FZDZ THIS EVENING.
HOWEVER AS SFC LOW VENTURES ACROSS NM/TX BORDER MOISTENING UPSLOPE
FLOW WILL DEEPEN SATURATED AIRMASS WITH TEMPS FALLING TO ~30F LATE
TONIGHT...THEREBY RESULTING IN -FZDZ OR =FZRA OVER KRSL & KSLN FROM
LATE TONIGHT THRU WED MORNING. WITH SE KS IN WARM SECTOR AIRMASS A
FEW EMBEDDED TSRA ARE POSSIBLE LATE TONIGHT & EARLY WED MORNING. W/
AREAL EXTENT QUITE LIMITED HAVE OPTED TO LEAVE TSRA OUT OF KCNU TAF
FOR NOW BUT WILL MONITOR SITUATION CLOSELY.
PREV DISCUSSION... /ISSUED 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
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 37 42 27 30 / 80 100 70 90
HUTCHINSON 33 36 26 28 / 100 100 80 90
NEWTON 36 40 26 30 / 90 100 70 90
ELDORADO 40 45 29 32 / 90 100 70 90
WINFIELD-KWLD 42 48 30 33 / 80 100 70 80
RUSSELL 29 32 20 21 / 100 100 90 90
GREAT BEND 30 33 23 23 / 100 100 90 80
SALINA 32 34 24 25 / 100 100 90 90
MCPHERSON 33 36 26 27 / 100 100 80 90
COFFEYVILLE 49 57 37 40 / 90 100 90 90
CHANUTE 46 54 35 38 / 90 100 80 90
IOLA 45 52 34 37 / 90 100 80 90
PARSONS-KPPF 48 56 37 39 / 90 100 90 90
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 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.
&&
$$