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 230402
AFDARX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
1102 PM CDT TUE JUL 22 2014

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 331 PM CDT TUE JUL 22 2014

A COOL FRONT WAS MAKING ITS WAY ACROSS THE FORECAST AREA THIS
AFTERNOON WITH THE INITIAL IMPACT BEING A DROP IN DEW POINTS. AT 3
PM THIS AFTERNOON THE FRONT WAS LOCATED FROM NEAR NECEDAH WISCONSIN
SOUTHWEST TO AROUND DESOTO TO NEAR OELWEIN IOWA. BEHIND THE FRONT
DEW POINTS WERE FALLING INTO THE 60S. AHEAD OF THE FRONT DEW
POINTS WERE SULTRY...IN THE MID TO UPPER 70S. THESE DEW POINTS
COMBINED WITH TEMPERATURES  IN THE UPPER 80S TO THE LOWER 90S
WERE PRODUCING  HEAT INDEX VALUES OF 100 TO 105. RELIEF WILL
ARRIVE LATE THIS AFTERNOON WITH THE PASSAGE OF THE COOL FRONT.
STRONG INSTABILITY HAS DEVELOPED IN THIS SULTRY AIRMASS WITH
SURFACE BASED CAPE VALUES APPROACHING 4500 J/KG. A STORM OR TWO
CANNOT BE RULED OUT ALONG THE FRONT THIS AFTERNOON BUT IT LOOKS
THE FRONT WILL WAIT TO IGNITE CONVECTION UNTIL IT SLIPS INTO
NORTHERN ILLINOIS/EAST CENTRAL IOWA LATER THIS AFTERNOON INTO
EARLY THIS EVENING...IF IT DEVELOPS AT ALL WITH THE STRONG CAP IN
PLACE. 0-6 KM SHEAR VALUES COULD SUPPORT A STRONG TO SEVERE STORM
BUT GIVEN THE CAP ITS UNLIKELY CONVECTION WILL EVEN OCCUR.
OTHERWISE...PLEASANT TEMPERATURES AND DEW POINTS MOVE INTO THE
REGION TONIGHT IN THE WAKE OF THE FRONT UNDER PARTLY CLOUDY TO
MOSTLY CLEAR SKIES. PLAN ON OVERNIGHT LOWS RANGING FROM THE MID
50S OVER NORTH CENTRAL WISCONSIN TO AROUND 60 ACROSS NORTHEAST
IOWA.

HIGH PRESSURE CONTINUES TO BUILD INTO THE REGION ON WEDNESDAY WITH
DRY AND QUIET WEATHER EXPECTED. LINGERING MOISTURE...IN THE 900 TO
850 MB LAYER...OVER THE REGION WILL LEAD TO LATE MORNING AND
AFTERNOON FLAT CUMULUS CLOUDS SO HAVE INCREASED SKY COVER SLIGHTLY
OVER THE PREVIOUS FORECAST. OTHERWISE LOOK FOR PLEASANT CONDITIONS
WITH HIGHS IN THE MID TO UPPER 70S AND DEW POINTS IN THE 50S MAKING
IT FEEL VERY COMFORTABLE.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 331 PM CDT TUE JUL 22 2014

THE HIGH WILL REMAIN IN CONTROL INTO THURSDAY PROVIDING DRY AND
QUIET WEATHER. THERE COULD BE COME PATCHY FOG ACROSS THE AREA LATE
WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING ESPECIALLY ACROSS
CENTRAL WISCONSIN AND OVER THE RIVER VALLEY LOCATIONS. A SURFACE
TROUGH DEVELOPS OVER THE CENTRAL AND NORTHERN PLAINS ON FRIDAY AND
EDGES EAST. 850 MB MOISTURE TRANSPORT INCREASES INTO THE AREA
THURSDAY NIGHT INTO FRIDAY AS A SHORTWAVE MOVES THROUGH. THIS SYSTEM
COULD BRING SOME SHOWERS AND THUNDERSTORMS TO THE AREA. THERE
REMAINS SOME TIMING ISSUES WITH THIS FEATURE IN THE FORECAST
MODELS SO HAVE LEANED TOWARD A MODEL CONSENSUS BLEND FOR THIS
TIMEFRAME. A VIGOROUS TROUGH THEN DIVES INTO THE UPPER MISSISSIPPI
RIVER VALLEY FROM NORTHERN MINNESOTA/EASTERN NORTH DAKOTA SATURDAY
INTO SATURDAY NIGHT. THIS TROUGH MAY GENERATE MORE SHOWERS AND
STORMS ACROSS THE AREA. THIS TROUGH SETS THE STAGE TO DIG A DEEP
TROUGH ACROSS THE EASTERN CONUS LATE THIS WEEKEND INTO NEXT WEEK.
THIS PATTERN WOULD CONTINUE TO SUPPORT WELL BELOW NORMAL
TEMPERATURES WITH HIGHS IN THE LOWER TO MID 70S. SATURDAY LOOKS TO
BE THE WARMEST DAY OF THE WEEKEND WITH HIGHS CLIMBING INTO THE
UPPER 70S TO LOWER 80S.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1102 PM CDT TUE JUL 22 2014

HIGH PRESSURE OVER THE DAKOTAS WILL BUILD INTO THE TAF SITES THIS
EVENING...BRINGING PLENTY OF DRY AIR WITH IT. THIS DRY AIR SHOULD
KEEP CONDITIONS VFR FOR THE NEXT 24 HOURS. REALLY ONLY CONCERN
WOULD BE SOME POSSIBLE VALLEY FOG/STRATUS AT LSE IN THE MORNING...
BUT LACK OF RAIN FOR THE LAST WEEK AND A NORTHERLY BREEZE
IMMEDIATELY ABOVE THE GROUND SHOULD HELP PREVENT BOTH. CANNOT RULE
OUT SOME SCATTERED CLOUDS FORMING ABOVE THE RIVER...THOUGH.

&&

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

$$

SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...AJ


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