FXUS63 KDDC 010932
AFDDDC
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DODGE CITY KS
332 AM CST TUE DEC 1 2009
.DISCUSSION...
DAYS 1-2...
THE MAIN FORECAST DECISION IS THE TIMING OF A STRONG COLD FRONT IN
THE NEXT 18 TO 24 HOURS.
THE SURFACE ANALYSIS FROM 08Z SHOWED A TROUGH FROM NORTHEAST
NEBRASKA THROUGH EASTERN COLORADO INTO NORTHEASTERN NEW MEXICO. A
COLD FRONT WAS MOVING SOUTH THROUGH MONTANA AND SHOULD CONTINUE ON
A STEADY PACE SOUTH-SOUTHEASTWARD. MOST MODELS BRING IT INTO OUR
NORTHERN CWA BY ABOUT 21Z TODAY, AND THEN PLUNGE IT SOUTH THROUGH
DDC ABOUT 02/00Z AND THROUGH ALL OF OUR CWA BY 06Z. THE WIND
BEHIND THE FRONT IS ANOTHER CHALLENGE TONIGHT AND WEDNESDAY. FOR
NOW, WILL FOLLOW THE MET AND MAV GUIDANCE AND KEEP WINDS DOWN IN THE
23-24KT RANGE AFTER THEY SHIFT NORTH BEHIND THE FRONT TONIGHT.
GUSTS WILL BE UP IN THE 30 TO 33KT RANGE, ESPECIALLY SOUTHEAST OF A
LARNED TO LIBERAL LINE. IF THE PRESSURE GRADIENT WOULD END UP
TIGHTER THAN CURRENTLY FORECAST, ADVISORY WINDS COULD RESULT FOR A
SHORT PERIOD, BUT DO NOT THINK THIS WILL BE THE CASE.
TODAY'S MAXIMUM TEMPERATURES SHOULD BE REACHED EARLY, WITH
INCREASING CLOUDS LATE. DID NOT CHANGE THE PREVIOUS FORECAST AT
ALL TODAY, WITH MAXES IN THE RANGE FROM 50F IN EHA TO 57F AT HYS.
WITH THE FRONT COMING THROUGH THIS EVENING, TEMPERATURES COULD FALL
FAST AFTER THE FROPA, DIPPING INTO THE MID 20S IN THE NORTH AND
WESTERN CWA. DUE TO A SLIGHTLY LATER FROPA IN MY SOUTHEAST, THING
P28 WILL ONLY FALL TO NEAR 30F. ALSO, DUE TO HIGHER DEW POINTS IN
THE SOUTHEAST, WILL HAVE SLIGHT CHANCE POPS FOR LIGHT RAIN LATE
THIS EVENING AND TONIGHT. DO NOT EXPECT ANY, OR VERY MUCH,
ACCUMULATION HOWEVER. THE FRONT WILL ENCOUNTER BETTER MOISTURE
AFTER IT PASSES SOUTH OF OUR CWA TONIGHT.
THE AIR MASS BEHIND THE FRONT IS CONSIDERABLY COLDER, SO MAX TEMPS
WILL TAKE A DIVE WEDNESDAY INTO THE MID 30S IN MY NORTH AND THE LOWER
40S SOUTH. CLOUDS WILL BE IN THE MOSTLY CLOUDY CATEGORY, AND WINDS
WILL BE BRISK OUR TO THE NORTH AT 15 TO 30 MPH, MAKING THE AMBIENT
TEMPERATURE FEEL EVEN COLDER. THIS CHANGE WILL BE FELT BY NEARLY
EVERYBODY, ESPECIALLY OUTDOOR WORKERS. THE WIND CHILL INDICES WILL
BE IN THE 20S MOST PLACES WEDNESDAY. WEDNESDAY NIGHT MAY WELL BE
THE COLDEST NIGHT OF THE SEASON. CLOUDS WILL BE DECREASING, AS
WELL AS WINDS. EXPECT TEMPERATURES TO PLUMMET INTO THE TEENS,
RANGING FROM 14F AT GCK TO 19F AT P28. NORTHWEST WIND IN THE 10 TO
15 MPH RANGE WILL PRODUCE WIND CHILLS AS LOW AS 7-8F IN OUR
NORTHWEST HALF OF THE CWA...BRRR.
DAYS 3-7...
THE COLD UPPER TROUGH AND ASSOCIATED DEEP COLD AIR WILL EXIT BY
SATURDAY WITH WEAK LEE TROUGHING AND A SLIGHT WARMUP. THE MODELS ARE
INDICATING STRONG AMPLIFICATION BY THE WEEKEND, WITH UPPER RIDGING
POKING UP INTO ALASKA, AN UPPER TROUGH DROPPING SOUTH ON THE EASTERN
SIDE OF THIS RIDGE, AND ARCTIC HIGH PRESSURE SLIDING SOUTH-SOUTHEAST
IN THE LEE OF THE ROCKIES. THIS COLD SURGE WILL BE MORE SHALLOW THAN
ITS PREDECESSOR GIVEN THE ZONAL MID LEVEL FLOW ACROSS THE ROCKIES.
DECIDED TO LOWER MAXES FOR THE SUN/MON TIME FRAME AND THESE NUMBERS
MAY NOT BE COLD ENOUGH. MAXES MAY STAY IN THE 20S IF LOW CLOUD COVER
DEVELOPS SUN/MON. ALSO, MODELS TEND TO UNDERESTIMATE THESE SHALLOW
COLD SURGES. SOME VERY LIGHT PRECIP IS POSSIBLE IN THIS SHALLOW
AIR MASS BUT LEFT OUT FOR NOW. THE MODELS DISAGREE ON THE AMPLITUDE
OF THE UPPER TROUGH IN THE SW CONUS BY THE BY MON-TUE TIME FRAME,
WITH THE CANADIAN BEING THE DEEPEST AND ECMWF/GFS LESS AMPLIFIED. IT
WILL HAVE TO BE FAIRLY DEEP TO GET SUFFICIENT MOISTURE RETURN FOR
SIGNIFICANT PRECIP.
&&
.AVIATION...
VFR CONDITIONS WILL PERSIST THROUGH 24 HRS. A COLD FRONT WILL PASS
THROUGH THE TAF SITES AROUND 00 UTC, WITH WINDS SHIFTING TO THE NORTH
AND INCREASING TO 20KTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 56 27 37 16 / 0 0 0 0
GCK 56 25 37 14 / 0 0 0 0
EHA 50 25 38 15 / 0 0 0 0
LBL 53 28 40 17 / 0 0 0 0
HYS 57 25 36 15 / 0 0 0 0
P28 53 30 42 19 / 20 20 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
FN12/24/24
