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 261901
AFDARX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
200 PM CDT SAT JUL 26 2014

.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 200 PM CDT SAT JUL 26 2014

WATER VAPOR IMAGERY SHOWING A CLOSED LOW OVER SOUTHERN MANITOBA
CANADA WITH A FAIRLY HIGH ZONAL FLOW ACROSS THE NORTHERN TIER OF THE
CONUS. FAIRLY STRONG 850-500MB FRONTOGENESIS WAS PRODUCING A
SCATTERED BAND OF SHOWERS/ISOLATED THUNDERSTORMS ALONG AND SOUTH OF
THE I-90 CORRIDOR FROM THE MISSISSIPPI RIVER...BACK TO NEAR SIOUX
FALLS SD. DESPITE THICK CLOUD COVER ACROSS THE ARX FORECAST AREA...
TEMPERATURES WERE IN THE UPPER 70S/LOWER 80S. WITH DEW POINTS IN THE
60S/LOWER 70S...RATHER MUGGY CONDITIONS WERE ALSO IN PLACE.

RAP SHOWS BAND OF 850-500MB FRONTOGENESIS WEAKENING/SAGGING SOUTH
OUT OF THE AREA INTO IL BY EARLY THIS EVENING...TAKING
SHOWERS/ISOLATED THUNDERSTORMS WITH IT. FOCUS THEN TURNS TO THAT
CLOSED LOW DROPPING SOUTHEAST OUT OF SOUTHERN MANITOBA INTO NORTHERN
MN/WI TONIGHT. STRONG 700-300MB PV-ADVECTION/QG-RESPONSE ASSOCIATED
WITH THIS WAVE ALONG WITH STEEPENING MID-LEVEL LAPSE RATES. THIS
WILL PRODUCE SCATTERED SHOWERS AND THUNDERSTORMS NORTH OF I-94 THIS
EVENING INTO EARLY SUNDAY MORNING. IN FACT...NAM INDICATES ELEVATED
MUCAPE IN THE 850-300MB LAYER OF 1500-1800J/KG ALONG WITH BULK SHEAR
IN THE 25-45KT RANGE. WILL THEREFORE HAVE TO KEEP AN EYE ON THE
POSSIBILITY OF A FEW STRONGER STORMS WITH LARGER HAIL/WIND
POTENTIAL. OTHERWISE...LOOK FOR LOWS TONIGHT IN THE UPPER 50S TO THE
MIDDLE 60S.

THE LIKELIHOOD OF SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE
THROUGH SUNDAY AS THE CLOSED LOW DRIFTS SOUTHEAST ACROSS THE REGION.
COOLER BREEZY CONDITIONS WILL ALSO BE SEEN WITH HIGHS ONLY TOPPING
OFF IN THE 70-80 DEGREE RANGE AS NORTHWEST WINDS BLOW AT 10 TO 20
MPH.

FOR SUNDAY NIGHT...PLAN ON SHOWERS TAPERING OFF RAPIDLY FROM WEST TO
EAST WITH A FEW EVENING SHOWERS LINGERING ACROSS CENTRAL WI THROUGH
9 PM. OTHERWISE...SURFACE HIGH PRESSURE BUILDING IN FROM THE
NORTHERN PLAINS WILL PRODUCE A DIMINISHING TREND TO THE CLOUDS WITH
OVERNIGHT TEMPERATURES DROPPING INTO THE UPPER 40S/LOWER 50S ACROSS
CENTRAL WI...TO THE MIDDLE 50S ELSEWHERE.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 200 PM CDT SAT JUL 26 2014

COOLER AND DRIER CONDITIONS WILL FILTER INTO THE AREA MONDAY/MONDAY
NIGHT AS HIGH PRESSURE ESTABLISHES ITSELF ACROSS THE UPPER
MISSISSIPPI RIVER REGION. LOOK FOR HIGHS MONDAY IN THE LOWER/MIDDLE
70S AND LOWS MONDAY NIGHT IN THE UPPER 40S ACROSS THE
SANDY/CRANBERRY BOG AREAS OF CENTRAL WI...TO THE LOWER/MIDDLE 50S
ELSEWHERE.

A FEW SHOWERS MAY SNEAK INTO PORTIONS OF EASTERN/CENTRAL WI ON
TUESDAY AS THE MODELS BRING ANOTHER WEAK MID-LEVEL TROUGH SOUTHWARD
THROUGH THE REGION. HIGHS TUESDAY LOOK TO BE IN THE MID/UPPER 70S.

COOLER CYCLONIC FLOW ALOFT CONTINUES THROUGH THE REMAINDER OF THE
PERIOD WITH CHANCES OF MAINLY DAYTIME HEATING SHOWERS/ISOLATED
THUNDERSTORMS. OTHERWISE...LOOK FOR HIGHS IN THE 75-80 DEGREE RANGE
WITH LOWS IN THE MIDDLE 50S TO LOWER 60S. THESE TEMPERATURE ARE MORE
TYPICAL OF EARLY SEPTEMBER.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1219 PM CDT SAT JUL 26 2014

COMPLEX OF SHOWERS AND STORMS OVER EASTERN SD THIS MORNING HAS
SHIFTED SOUTHEAST INTO WESTERN IA/EASTERN NEB. COOL OUTFLOW SHOWERS
IN MID LEVEL CONVERGENT AREA STRINGING EAST ALONG THE MN/IA BORDER
REGION. LITTLE MORE THAN SPRINKLES AT THE KRST/KLSE AIRFIELDS...BUT
MORE SHOWERS LOOK TO IMPACT KRST FOR THE EARLY AFTERNOON. COMPLEX
SHIFTING SLIGHTLY SOUTH OF EAST SO CONFIDENT IT WILL MISS KLSE.
STILL...LOW CLOUD LINGERING IN THE WEAK FLOW ENVIRONMENT KEEPING
INVERSION IN PLACE. DO FEEL THE LOWER CLOUD WILL MIX OUT ONCE THE
SHOWER AREA PASSES BY MID TO LATE AFTERNOON. MEANWHILE A NICE SHORT
WAVE TROUGH IS MOVING THROUGH SOUTHERN CANADA NEAR WINNIPEG WILL
DROP SOUTHEAST ACROSS MN TONIGHT AND INTO WI BY SUNDAY. DESPITE
MINIMAL MOISTURE AVAILABLE...STRONG FORCING AND STEEP MID-LEVEL
LAPSE RATES LOOK TO FORCE STORMS DURING THE EVENING/OVERNIGHT HOURS.
BUT THESE LOOK TO REMAIN WELL NORTH AND EAST OF THE TAF LOCATIONS.
ONLY IMPACT WILL PERHAPS BE SOME CLOUD COVER AND A WIND SWITCH TO
NORTHWEST. BEHIND THE UPPER SYSTEM EXPECT LOW LEVEL MOISTURE TO
MANIFEST AS CLOUD AND GUSTY WINDS TOMORROW.

&&

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

$$

SHORT TERM...DAS
LONG TERM...DAS
AVIATION...WELVAERT



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