FXUS63 KDDC 092046
AFDDDC
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DODGE CITY KS
246 PM CST WED DEC 9 2009
.DISCUSSION...
DAYS 1-2...
THE HARDEST PART OF THIS FORECAST PACKAGE IS TEMPERATURES, AND THE
NEED FOR A WIND CHILL ADVISORY OR NOT TONIGHT.
WITH 4 TO 9 INCHES OF FRESH SNOW ACROSS OUR NORTHERN 1/3RD CWA OR
SO, AND STRONG ARCTIC HIGH PRESSURE CURRENTLY BUILDING SOUTH FROM
THE WESTERN HIGH PLAINS OF WESTERN NEBRASKA AND WESTERN SOUTH
DAKOTA, A VERY COLD NIGHT IS STORE. HAVE ASSESSED WHERE THE
DEEPEST SNOW IS, BASICALLY NORTH A LINE FROM GARDEN CITY TO
JETMORE TO KINSLEY TO LARNED. WILL ISSUE A WIND CHILL ADVISORY
NORTH OF THAT LINE, EVEN THOUGH WINDS SPEEDS WILL BE 10 MPH OR LESS.
THE GUIDANCE FOR HYS AND RSL ONLY SHOW LOW TEMPS IN THE -4F RANGE,
BUT THINK THE SNOW COVER WILL ALLOW FOR FASTER DIURNAL HEAT LOSS
AND MIN TEMPS SHOULD DROP TO CLOSER TO 10F BELOW ZERO. WITH THAT
COLD OF AN AMBIENT TEMPERATURE, ANY WIND WILL PRODUCE WIND CHILLS
BELOW MINUS 20F. SO, TRACED WHERE THE COMBO OF BOTH VERY COLD
TEMPERATURES, WINDS NEAR OR CLOSE TO 10 MPH, BOTH PRODUCED WIND
CHILLS DOWN TO MINUS 20F, BASICALLY WHERE THE DEEPER SNOW FIELD
IS. WENT FROM 00Z TO 16Z, TO ALIGN BETTER WITH SURROUNDING
OFFICES.
AS FOR THURSDAY, THE ARCTIC SURFACE HIGH WILL SHIFT EAST BUT STILL
HAVE A GOOD GRIP ON OUR AREA. WINDS SHOULD SHIFT SOUTH AS THE HIGH
GLIDES EAST, BRING A LITTLE WARMING TO THE LOWER LAYERS. THE
NORTHERN CWA WILL STILL BE THE COOLEST WITH MAX T'S IN THE UPPER
TEENS, RANGING UPWARD TO THE LOWER 30S ALONG THE OKLAHOMA BORDER
WHERE NO SNOW WILL BE LEFT. MIN TEMPERATURES FOR THURSDAY NIGHT
WILL BE TRICKY AS SOUTH WINDS SHIFT SOUTHWEST (ONLY LIGHT), AND
SOME UPPER CLOUDS FLOW OVER THE AREA. STAYED NEAR THE PREVIOUS
FORECAST VALUES OF -2 AT HYS RANGING TO 18F AT EHA. THE PROGGED
850MB TEMPERATURES WOULD SUGGEST SOME LOWER 40S FOR FRIDAY, BUT
STILL THINK MY NORTHERN CWA WILL BE INFLUENCED BY THE SNOW AND
ONLY REACH THE MID 20S FOR HIGHS. DOWN SOUTH ALONG THE OKLAHOMA
BORDER, I EXPECT HIGHS IN THE MID 30S.
DAYS 3-7...
A WARMUP WILL CONTINUE SAT/SUN AS SNOWCOVER CONTINUES TO MELT. I WOULD
EXPECT AREAS THAT RECEIVED 1 TO 3 INCHES OF SNOW TO BE SNOWFREE BY
THIS TIME. A SHORTWAVE TROUGH WILL PASS ACROSS THE CENTRAL PLAINS
ON SUNDAY. SFC PRESSURES ARE PROGGED BY ALL MODELS TO DROP TO CLOSE TO
1000MB WITH 850MB TEMPS WARMING TO BETWEEN +6 NORTH AND +10-12 SOUTH.
STRONG MIXING SHOULD OCCUR GIVEN THE PASSAGE OF THE PROGRESSIVE
TROUGH, SO MAXES FROM JETMORE SOUTH SHOULD HAVE NO PROBLEM WARMING
INTO THE 50S, WITH EVEN SOME LOWER 60S ON THE LOWER TERRAIN OF CLARK,
COMANCHE AND BARBER COUNTIES.
THE BIGGEST FORECAST CHALLENGE FOR EARLY NEXT WEEK IS WHETHER A SHALLOW
COLD AIRMASS WILL PUSH DOWN THE PLAINS FOR MON/TUE. THE MODELS HAVE
BEEN DISPLAYING HIGHLY VARIABLE SOLUTIONS BUT THE OVERALL TREND IS
FOR THE COLD INTRUSION TO BE LATER(MON/TUE INSTEAD OF SAT/SUN) AND
DEEPER AS OPPOSED TO SHALLOW PER GFS. BUT THERE IS EVEN SOME DOUBT
AS TO WHETHER THE COLD SURGE WILL OCCUR AT ALL(SEE ECMWF SOLUTION).
GIVEN THE UNCERTAINTY, DECIDED KEPT A MIDDLE OF THE ROAD TEMPERATURE
FORECAST FOR EARLY TO MID NEXT WEEK.
REGARDLESS OF THE MODEL CHOICE, SIGNIFICANT PRECIPITATION EVENTS ARE
HIGHLY UNLIKELY THROUGH DEC 19 AND PROBABLY BEYOND.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC -6 26 10 32 / 0 0 0 10
GCK -8 26 9 32 / 0 0 0 10
EHA 6 31 18 38 / 0 0 0 10
LBL -1 31 14 36 / 0 0 0 10
HYS -10 18 -2 24 / 0 0 0 10
P28 4 31 16 37 / 0 0 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 10 AM CST THURSDAY
FOR KSZ030-031-043>046-063>065.
&&
$$
FN12/24/24
