Area Forecast Discussion
Issued by NWS La Crosse, WI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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 260454
AFDARX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
1154 PM CDT FRI JUL 25 2014

.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 224 PM CDT FRI JUL 25 2014

WATER VAPOR IMAGERY/RAP 500MB ANALYSIS SHOWING A FAIRLY  FLAT RIDGE
OF HIGH PRESSURE IN PLACE ACROSS THE CENTRAL CONUS. A CLOSED LOW WAS
SITUATED OVER THE PLAINS OF ALBERTA/SASKATCHEWAN CANADA WITH A TROUGH
EXTENDING EAST-SOUTHEAST THROUGH THE UPPER MISSISSIPPI RIVER VALLEY.
AT THE SURFACE AN OCCLUDED FRONT EXTENDED FROM THE CLOSED LOW IN
CANADA INTO THE EASTERN DAKOTAS...WITH A TRIPLE POINT LOW LOCATED
OVER SOUTHEAST SD/NORTHEAST NEB. A WARM FRONT EXTENDED FROM THIS LOW
INTO WESTERN IA/MO. THERE WAS A NOSE OF 850MB MOISTURE TRANSPORT
AHEAD OF THE FRONT THAT SPAWNED CLUSTER OF SHOWERS AND THUNDERSTORMS
ACROSS PORTIONS OF OUR AREA THIS MORNING...BUT THIS HAS NOW SHIFTED
SOUTHEAST INTO IL. OTHERWISE...VISIBLE SATELLITE IMAGERY SHOWING
QUITE A BIT OF LINGERING STRATOCUMULUS/CUMULUS BEHIND THE DEPARTED
SHOWERS/STORMS WITH TEMPERATURES HOVERING IN THE 70S.

FOR TONIGHT...WILL BE SEEING THAT OCCLUDED FRONT MOVE OVERHEAD
TONIGHT WITH A FAIRLY BAGGY SURFACE PRESSURE GRADIENT. THINKING WE
WILL SEE AT LEAST SOME PARTIAL CLEARING OVERNIGHT...AND WITH LIGHT
WINDS AND A FAIRLY DAMP LOWER BOUNDARY LAYER FROM TODAYS
RAINFALL...WILL SEE THE POTENTIAL FOR SOME FOG AND/OR STRATUS MAINLY
IN THE RIVER VALLEYS. WILL HAVE TO KEEP AN EYE ON THIS GOING INTO
TONIGHT.

ON SATURDAY...THERE ARE HINTS AT SOME ELEVATED CONVECTION ACROSS IA
INTO IL DURING THE AFTERNOON IN RESPONSE TO SOME JET ENERGY AND
POOLING CAPE ALONG A FRONTAL BOUNDARY ACROSS THAT AREA. BUFKIT SHOWS
A STRONG 850MB CAP IN PLACE WITH THIS CONVECTION POTENTIAL LOOKING
LIKE IT WILL BE ABOVE 700MB. AS A RESULT...HAVE KEPT OUR FORECAST
AREA DRY FOR NOW AND INCREASED CLOUDS SOME. OTHERWISE...PLAN ON A
SEASONABLY WARM/MODERATELY HUMID DAY WITH HIGHS IN THE 80S AND
DEWPOINTS IN THE 60S.

SATURDAY NIGHT WILL SEE A CLOSED LOW DROP SOUTHEAST OUT OF SOUTHERN
CANADA INTO NORTHERN MN/WI BY MORNING. LIFT OUT AHEAD OF THE LOW AND
STEEPENING MID-LEVEL LAPSE RATES WILL PRODUCE A CHANCE OF SHOWERS
AND ISOLATED THUNDERSTORMS MAINLY NORTHEAST OF THE I-94 CORRIDOR.
LOOK FOR LOWS IN THE 60-65 DEGREE RANGE.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 224 PM CDT FRI JUL 25 2014

COOLER TEMPERATURES ALONG WITH THE LIKELIHOOD OF SHOWERS AND
ISOLATED THUNDERSTORMS CAN BE EXPECTED ON SUNDAY AS THE CLOSED LOW
ROTATES SOUTHEASTWARD ACROSS THE AREA. PLAN ON HIGHS COOLING INTO
THE 70S WITH BREEZY NORTHWEST WINDS AS WELL IN THE 10-20 MPH RANGE.
A FEW LINGERING SHOWERS MAY STILL BE POSSIBLE ACROSS CENTRAL WI
SUNDAY NIGHT...BUT THEN HIGH PRESSURE BUILD IN FOR THE REST OF THE
NIGHT FOR CLEARING AND COOL CONDITIONS. LOOK FOR LOWS IN THE 50S.

HIGH PRESSURE WILL CONTINUE TO DOMINATE THE REGION MONDAY THROUGH
MONDAY NIGHT FOR DRY AND COOLER THAN NORMAL TEMPERATURES. PLAN ON
HIGHS MONDAY IN THE 69-75 DEGREE RANGE WITH LOWS MONDAY NIGHT
DIPPING INTO THE LOW-MID 50S.

FOR TUESDAY THROUGH FRIDAY...MODELS IN GOOD AGREEMENT WITH A DEEP
TROUGH/CLOSED LOW ESTABLISHING ITSELF OVER THE UPPER MISSISSIPPI
RIVER/GREAT LAKES/OHIO RIVER VALLEY REGIONS. THIS WILL LEAD TO
COOLER THAN NORMAL TEMPERATURES WITH DAYTIME HEATING INSTABILITY
SHOWERS/ISOLATED THUNDER. LOOK FOR HIGHS THROUGH THE PERIOD IN THE
70S WITH OVERNIGHT LOWS IN THE 50S...WHICH IS MORE TYPICAL OF EARLY
SEPTEMBER.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1154 PM CDT FRI JUL 25 2014

THE FIRST 6 HOURS OR SO OF THE AVIATION FORECAST IS VERY
PROBLEMATIC. CEILINGS HAVE BEEN GRADUALLY LOWERING THROUGH THE
EVENING DUE TO A COMBINATION OF NOCTURNAL COOLING AND A LITTLE
MORE MOISTURE BEING SENT NORTHWARD INTO THE TAF SITES. EVEN SOME
DRIZZLE HAS FORMED...REDUCING VISIBILITIES TO MVFR AT RST.
MEANWHILE...DRIER AIR AS EXPECTED IS BEGINNING TO MOVE INTO
SOUTHEAST MN WITH TOB NOW VFR. AS WE HEAD THROUGH THE EARLY
MORNING HOURS...ANTICIPATING THAT DRIER AIR TO MOVE INTO RST...
CAUSING THE CLOUDS TO SCATTER OUT AND THUS GO VFR. HOWEVER...THIS
SAME CLEARING MAY ALLOW IFR OR LOWER VISIBILITY BR TO DEVELOP...
WHICH IS NOTED IN A TEMPO GROUP. ANY FOG SHOULD DISSIPATE QUICKLY
AFTER SUNRISE. AT LSE...IT APPEARS THE CLEARING MAY TAKE LONGER TO
GET THERE...THUS HAVE LEFT THE PREVIOUS PLAN OF CONDITIONS
CLIMBING TO VFR AFTER 13Z. ITS POSSIBLE LSE DROPS TO IFR EARLY
THIS MORNING. AFTER 13Z...PLENTIFUL DRY AIR LOOKS TO BE PRESENT
ABOVE THE SURFACE TO NEARLY 10000 FT TO ALLOW FOR VFR CONDITIONS.

&&

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

$$

SHORT TERM...DAS
LONG TERM...DAS
AVIATION...AJ



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