FXUS63 KARX 150826
AFDARX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
225 AM CST TUE DEC 15 2009

.SHORT TERM...TODAY THROUGH THURSDAY

FORECAST CONCERNS FOCUS ON THE COLD FOR THE NEXT COUPLE DAYS.

ITS BEEN QUITE A PAST 7 DAYS OF WINTER WEATHER FOR THE 
REGION...STARTING WITH A MAJOR WINTER STORM/BLIZZARD...FOLLOWED A 
FEW DAYS LATER BY WIDESPREAD FREEZING DRIZZLE/LIGHT SNOW...AND NOW 
SOME BITTER COLD AND DANGEROUS WIND CHILLS. QUIETER CONDITIONS DO 
LOOK TO RETURN TO THE REGION BY THE WEEKEND.

A SFC HIGH WAS LOCATED ACROSS THE PLAIN STATES EARLY THIS 
MORNING...WHILE A LOFT A SHORTWAVE TROUGH WAS DROPPING ACROSS THE 
NORTHERN GREAT LAKES. NOT MUCH ACTIVITY WITH THIS UPPER LEVEL 
FEATURE THOUGH...AS SUBSIDENCE AND DRY AIR FROM THE HIGH PRESSURE IS 
KEEPING MOST OF THE REGION CLEAR //PER FOG/STRATUS SATELLITE 
PRODUCT//. SOME CLOUDS STILL LINGERING OVER EASTERN WI...ON THE BACK 
EDGE OF THE SYSTEM THAT BROUGHT THE FREEZING DRIZZLE/LIGHT SNOW 
YESTERDAY. 

THE HIGH PRESSURE WILL SLIP ACROSS ILL BY 12Z WED...GRADUALLY EASING 
EAST AND WEAKENING SOME TOWARD THE WEEKEND. A GOOD AMOUNT OF COLD 
ARCTIC AIR WILL ACCOMPANY THIS HIGH...WITH THE 14.12Z GEFS 850 MB 
TEMP ANOMALIES AROUND 1-1.5 ACROSS THE FORECAST AREA INTO WED. WITH 
CLOUDS EXPECTED TO BE RELATIVELY SCARCE THROUGH WED MORNING...AND 
WINDS LIGHTENING UP AS THE HIGH MOVES NEARLY OVERHEAD...IT SHOULD BE 
A DECENT RADIATIONAL COOLING NIGHT. LOWS OF 5 TO 10 BELOW FOR THE 
FORECAST AREA LOOKS GOOD...WITH A FEW COLDER TEMPS POSSIBLE IN THE 
SHELTERED AND/OR DRAINAGE AREAS. LOW LEVEL WARM AIR ADVECTION DOES 
START TO KICK IN DURING THE OVERNIGHT HOURS HOWEVER...SO LOWS MAY 
OCCUR MORE IN THE 06-09Z TIME FRAME RATHER THAN AROUND 
13Z...ESPECIALLY WEST OF THE MISSISSIPPI RIVER. WINDS WILL NOT BE AS 
BREEZY AS THIS MORNING...IN FACT...MOST LOCATIONS CAN EXPECT LIGHT 
TO CALM WINDS WED MORNING. HOWEVER...THERE COULD BE ENOUGH WIND THAT 
WIND CHILLS WILL BE A FACTOR AGAIN...MOSTLY IN THE WIND PRONE/OPEN 
AREAS OF SOUTHEAST MN AND NORTHEAST IA. CURRENT FORECAST DROPS WIND 
CHILLS INTO THE -20 TO -25 RANGE FOR FOR A BRIEF PERIOD OF TIME 
OVERNIGHT. WIND CHILL ADVISORIES WILL HAVE TO BE 
CONSIDERED...ALTHOUGH THE ANTICIPATED WARMING TEMPS TOWARD SUNRISE 
WED MAY PRECLUDE THE NECESSITY FOR AN ADVISORY.   

SPEAKING OF WIND CHILL ADVISORIES...THE CURRENT ADVISORY FOR 
SOUTHEAST MN/NORTHEAST IA LOOKS GOOD. COLD AIR CONTINUES TO ADVANCE 
SOUTHEAST...AND LOWS ARE STILL EXPECTED TO BOTTOM OUT BELOW ZERO FOR 
MOST OF THE FORECAST AREA. WIND CHILLS ALREADY -20 OR COLDER FOR 
MOST OF MN...AND THESE SHOULD BE REALIZED WEST OF THE MISSISSIPPI 
RIVER. SOME MISSISSIPPI RIVER COUNTIES MAY BE CLOSER TO -20...BUT 
OVERALL...WILL CONTINUE THE ADV AS CURRENTLY CONFIGURED. 

THE 15.00Z GFS/NAM DO WANT TO BRING A COUPLE SHORTWAVE TROUGHS DOWN 
THE NORTHWEST FLOW AND ACROSS THE AREA BETWEEN 12-18Z WED AND 18-00Z 
FRI. THE WED SYSTEM WILL HAVE SOME MID LEVEL SATURATION TO WORK 
WITH...AND COULD PRODUCE A FEW FLURRIES/SCATTERED SNOW SHOWER OR TWO 
ACROSS NORTHERN PARTS OF THE REGION. THE THU AFTERNOON/FRI EVENING 
SHORTWAVE LOOKS VERY SIMILAR...AND THE OUTCOME LOOKS THE SAME.  

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY

GFS/ECMWF IN DECENT AGREEMENT WITH THE OVERALL PATTERN FOR THE LOCAL 
AREA...WITH NORTHWEST FLOW ALOFT GIVING WAY TO MORE RIDGING BY THE 
START OF THE NEW WORK WEEK. EXPECT COOL TO NEAR SEASONABLE TEMPS 
THROUGH THE PERIOD. BOTH MODELS DO HINT AT A FEW DISTURBANCES 
DROPPING THROUGH THE FLOW...BUT LITTLE IF ANY QPF ASSOCIATED WITH 
THEM. THE ONE EXCEPTION IS SAT NIGHT/SUN...WHERE AN UPPER LEVEL 
SHORTWAVE TROUGH WILL DROP ACROSS THE EASTERN GREAT 
LAKES...POTENTIALLY SPREADING LIGHT PCPN AS FAR WEST AS EASTERN WI. 
STILL...WOULDN/T BE SURPRISED TO SEE A FEW FLURRIES OR SCATTERED 
SNOW SHOWERS FROM TIME TO TIME WITH ANY OF THESE UPPER LEVEL 
FEATURES. THE POTENTIAL FOR WIDESPREAD ACCUMULATING SNOWS LOOKS 
RATHER SMALL. ON GOING FORECAST HAS PERIODIC SMALL CHANCES IN THE 
FORECAST...AND WILL LIKELY LEAVE AS IS FOR NOW.    

&&

.AVIATION... 

HIGH PRESSURE TRANSITS THE AREA TODAY THROUGH TONIGHT...RESULTING
IN VFR CONDITIONS. NORTHWEST FLOW ALOFT SHOULD BRING BRIEF INTERVALS 
OF CLOUDS EARLY THIS MORNING AND AGAIN TONIGHT. CEILINGS ARE 
EXPECTED TO BE AT OR ABOVE 8KFT.
   
&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WIND CHILL ADVISORY TIL 11 AM CST TODAY
     FOR MNZ079-MNZ086-MNZ087-MNZ088-MNZ094-MNZ095-MNZ096.

IA...WIND CHILL ADVISORY TIL 11 AM CST TODAY
     FOR IAZ008-IAZ009-IAZ010-IAZ011-IAZ018-IAZ019-IAZ029-IAZ030.

&&

$$

SHORT/LONG TERM... RIECK
AVIATION.......... THOMPSON