Area Forecast Discussion
Issued by NWS La Crosse, WI

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS63 KARX 052013
AFDARX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
213 PM CST THU MAR 5 2015

.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 213 PM CST THU MAR 5 2015

RIDGE OF HIGH PRESSURE DEAD OVERHEAD THIS AFTERNOON WITH CLEAR SKIES
AND VERY CHILLY TEMPERATURES IN THE UPPER SINGLE DIGITS AND LOWER
TEENS ABOVE ZERO.

FOR TONIGHT...THE RIDGE OF HIGH PRESSURE WILL SHIFT EAST OF THE AREA
AS A WARM FRONT APPROACHES FROM THE NORTHERN PLAINS. THIS SETS UP
WARM AIR ADVECTION OVERNIGHT ON INCREASING SOUTHERLY WINDS. PLAN ON
TEMPERATURES TO DIP INTO THE SINGLE DIGITS BELOW/ABOVE ZERO THIS
EVENING...THEN STARTING A SLOW RISING TREND OVERNIGHT.

WARM FRONT MAKES PASSAGE THROUGH THE AREA ON FRIDAY WITH 925MB
TEMPERATURES INCREASING SOME 10C FROM THURSDAY INTO THE -8 TO -2C
RANGE. THERE WILL BE SOME INCREASE IN MID-LEVEL CLOUD...BUT NOT
ENOUGH TO KEEP THE SUN FROM HAVING ITS AFFECT IN COMBINATION WITH
THE WARM AIR ADVECTION. AS A RESULT...LOOK FOR TEMPERATURES TO
MODERATE INTO THE UPPER 20S TO THE MIDDLE 30S.

FOR FRIDAY NIGHT...NORTHWEST FLOW ALOFT BRINGS A WAVE OF LOW
PRESSURE ACROSS SOUTHERN CANADA/LAKE SUPERIOR. APPEARS BETTER
PRECIPITATION CHANCES ASSOCIATED WITH THE FORCING OF THIS WAVE WILL
STAY NORTH OF THE AREA...BUT MAINTAINED A SMALL CHANCE NORTH OF I-
94. OTHERWISE...LOW TEMPERATURES LOOK TO BE IN THE UPPER TEENS TO
LOWER 20S.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 213 PM CST THU MAR 5 2015

FOCUS IN THE LONG TERM WILL BE POSSIBLE ACCUMULATING SNOW SATURDAY
NIGHT INTO SUNDAY MORNING...THEN QUIET WITH A WARMING TREND INTO
NEXT WEEK.

WILL HAVE TO CONTEND WITH A LINGERING SMALL SNOW CHANCE ACROSS THE
NORTH...NORTH OF HIGHWAY 29 SATURDAY MORNING AS A MID-LEVEL TROUGH
SWINGS ACROSS THAT AREA. OTHERWISE...LOOKING LIKE A PARTLY SUNNY DAY
WITH HIGHS IN THE MIDDLE 30S TO NEAR 40.

LATEST 05.12Z ECMWF/GEM IN GOOD AGREEMENT IN BRINGING A FAIRLY
VIGOROUS MID-LEVEL TROUGH/WEAK SURFACE LOW ACROSS SOUTHERN
MN/SOUTHERN WI SATURDAY NIGHT INTO SUNDAY MORNING. MODERATELY STRONG
DYNAMICS FOR FORCING DESPITE LOW-END AVAILABLE MOISTURE. THE EC
SHOWS RIGHT ENTRANCE REGION OF 105-110KT 300MB JET AND MODERATE 850-
700MB FRONTOGENESIS. AS SUCH...THINKING THERE WILL BE A FAIRLY
TIGHT/FOCUSED AREA OF SNOW SOUTH OF THE I-94 CORRIDOR IN WISCONSIN.
RIGHT NOW..LOOKS LIKE 1-2 INCHES OF SNOWFALL WILL BE POSSIBLE LATE
SATURDAY NIGHT INTO SUNDAY MORNING...BEFORE THE WAVE DEPARTS TO THE
SOUTHEAST BY AFTERNOON. WILL HAVE TO KEEP AN EYE ON THIS FORCING AS
IT COULD SQUEEZE OUT A BIT MORE MOISTURE AND THEREFORE MORE
SNOWFALL. FOR NOW...BUMPED POPS INTO HIGHER CHANCE CATEGORY SINCE
GFS/NAM ARE FAIRLY DRY YET. LOOKS LIKE THIS SNOW WILL BE MELTING
GOING INTO SUNDAY AFTERNOON AS HIGHS WARM BACK INTO THE MIDDLE
30S/AROUND 40.

FOR MONDAY THROUGH THURSDAY...LATEST 05.12Z GFS/ECMWF CONTINUE TO
SHOW BUILDING HEIGHT/UPPER LEVEL RIDGING TAKING PLACE OVER THE
CENTRAL CONUS. THIS WILL LEAD TO WARMING TEMPERATURES WITH HIGHS
MONDAY LOOKING TO BE IN THE UPPER 30S TO THE MIDDLE 40S...AND INTO
THE MIDDLE 40S/MIDDLE 50S BY WEDNESDAY. GOING HIGHS ON THURSDAY
RIGHT NOW COOL BACK INTO THE UPPER 30S TO THE MIDDLE 40S...BUT FEEL
THEY MAY HAVE TO BE BUMPED UP AS WELL WITH MODELS COMING INTO BETTER
AGREEMENT ON RIDGE AMPLIFICATION.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY NOON)
ISSUED AT 1133 AM CST THU MAR 5 2015

DRY CAN/ARCTIC HIGH PRESSURE WILL CONTINUE TO BRING GOOD VFR
CONDITIONS TO THE AREA THRU TONIGHT/FRI MORNING...EVEN AS IT
RETREATS AND WARMER AIR START TO RETURN TO MN/IA/WI. DIURNAL
WARMING/ STEEP LOW LEVEL LAPSE RATES LOOK TO RESULT IN FEW STRATO-CU
THIS AFTERNOON...DISSIPATING QUICKLY WITH SUNSET.

MAIN CONCERN THE NEXT 24HRS IS THE CHANGE/INCREASE OF WIND AS THE
HIGH RETREATS AND A TROUGH/WARM FRONT PUSHES TOWARD THE AREA. WINDS
BECOME SOUTH/SOUTHWEST AND INCREASE WITH THE STRONGEST WINDS LATE
TONIGHT/EARLY FRI MORNING AHEAD OF THE WARM FRONT. SOUTHWEST TO WEST
WINDS AROUND 40KT ON TOP THE INVERSION NEAR 2K FT AGL LATE TONIGHT/
EARLY FRI...AND ADDED LLWS TO BOTH KRST/KLSE TAFS IN THE 09Z TO 14-
15Z TIMEFRAME WITH AN EXPECTED DIRECTION CHANGE OF AS MUCH AS 60
DEGREES. GRADIENTS RELAX WITH APPROACH OF THE FRONT/TROUGH FOR LATER
FRI MORNING.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&

$$

SHORT TERM...DAS
LONG TERM...DAS
AVIATION...RRS



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.