967
FXUS63 KARX 050533
AFDARX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
1233 AM CDT SUN JUL 5 2026
KEY MESSAGES
- AFTERNOON STORMS MOSTLY IN NORTHEAST IOWA MAY SPREAD EAST INTO
SOUTHWEST WISCONSIN AND NORTH TOWARDS THE MINNESOTA BORDER.
EVENING AND NIGHTTIME STORMS DIVE SOUTH-SOUTHEAST PRIMARILY
AFFECTING SOUTHEAST MINNESOTA, WEAKENING AS THEY APPROACH
DEPENDING ON DIURNAL TIMING.
- POTENTIAL FOR SLIGHTLY COOLER TEMPERATURES WITH STORMS
CIRCUMNAVIGATING THE FORECAST AREA THROUGH THE START OF THE
WEEK.
UPDATE
ISSUED AT 1221 PM CDT SAT JUL 4 2026
FUNNEL CLOUD POTENTIAL THIS AFTERNOON:
THE AIRMASS ACROSS NORTHERN IOWA EARLY THIS AFTERNOON IS
SPREADING EAST-NORTHEAST TOWARDS THE FORECAST AREA WITH REPORTS
OF FUNNEL CLOUDS. COMBINATION OF MOSTLY CLEAR SKIES CAUSING
STEEP LOW LEVEL LAPSE RATES WITH WEAK LOW LEVEL WINDS IS
INCREASING NON-SUPERCELL TORNADO VALUES NEAR 2 WELL WEST OF THE
LOCAL FORECAST AREA. GIVEN THE ENVIRONMENT, OVERALL CONFIDENCE
AND IMPACT THREAT IS LOW AS FUNNEL CLOUDS ARE USUALLY BRIEF,
DROPPING ONLY A FEW HUNDRED FEET FROM THE CLOUD BASE, AND RARELY
BECOME A TORNADO OR CAUSE DAMAGE. HAVE ISSUED AN SPS THROUGH 7PM
FOR THE POSSIBILITY IN NORTHEAST IOWA WHERE LOCAL THREAT IS
HIGHEST.
DISCUSSION
ISSUED AT 137 PM CDT SAT JUL 4 2026
STORM CHANCES THIS AFTERNOON/EVENING:
BURBLING STORMS ALONG RESIDUAL PAST STORM OUTFLOW BOUNDARIES HAVE
CAUSED STORMS IN SOUTHWESTERN COUNTIES OF THE LOCAL AREA IN
NORTHEAST IOWA. EXPECT THESE TO CONTINUE SPREADING EAST THROUGH THE
EARLY AFTERNOON, POTENTIALLY CONTINUING THROUGH SOUTHWEST WISCONSIN
TOWARDS LAKE MICHIGAN. THE ACCOMPANYING INSTABILITY GRADIENT ALSO
EXTENDS NORTH-NORTHWEST THROUGH SOUTHEAST MINNESOTA WHERE RECENT
RADAR REFLECTIVITY HAS EXHIBITED ISOLATED, SINGLE CELL, SHORT-LIVED
STORMS BURBLING EARLY THIS AFTERNOON.
STORM CHANCES THIS EVENING & TONIGHT:
STORM PROBABILITIES INCREASE THROUGH THE LATE EVENING INTO
TONIGHT PRIMARILY IN SOUTHEAST MINNESOTA AS THE STORMS IN
CENTRAL TO NORTHERN MINNESOTA EARLY THIS AFTERNOON FALL
SOUTHEAST ALONG A WEAK UPPER LEVEL PERTURBATION. CURRENT TIMING
SLIGHTLY AFTER DIURNAL HEATING SUGGESTS A WEAKENING TREND AS
STORMS APPROACH THE FORECAST AREA WHILE INSTABILITY RECEDES
SOUTHWEST. THEREFORE, DIURNAL TIMING WILL BE THE MAIN CONCERN
AFTER ANY, LIMITED, TRANSIENT, ISOLATED WEAK STORMS. LOCATION OF
LONGER DURATION STORMS THIS AFTERNOON CONSUMING AVAILABLE
INSTABILITY WILL ALSO INFLUENCE INSTABILITY INTO TONIGHT. LONGER
DURATION STORMS WILL LIMIT SUBSEQUENT UNSTABLE AIR, LIMITING
NIGHTTIME STORMS.
THROUGH THE NEW WEEK:
A WEAK LOW FORMATION OVER THE GREAT LAKES THROUGH SUNDAY DRAGS A
BACK DOOR COLD FRONT OVER MUCH OF THE UPPER MISSISSIPPI RIVER
VALLEY. LONG TERM GLOBAL ENSEMBLES AND ACCOMPANYING DETERMINISTIC
MODELS AGREE FOR THIS AREA OF CYCLONIC ROTATION LINGERING THROUGH
MIDWEEK, RESULTING IN LOCALLY COOLER TEMPERATURES THAN SURROUNDING
AREAS AND A SHIELD OF PRECIPITATION PROBABILITIES POTENTIALLY.
DIFFERENCES IN STRENGTH AND LOCATION OF THE LOW PRESSURE WILL BE THE
MAIN DRIVING FACTOR FOR LOCAL WEATHER IMPACTS AS A STRONGER SOLUTION
WILL RESULT IN STRONGER EAST WINDS OFF THE GREAT LAKES CAUSING
COOLER TEMPERATURES AND LESS PRECIPITATION CHANCES FOR MUCH OF THE
LOCAL AREA. PERIPHERAL STORMS AND PRECIPITATION WILL REMAIN POSSIBLE
REGARDLESS.
AVIATION /06Z TAFS THROUGH 06Z MONDAY/
ISSUED AT 1234 AM CDT SUN JUL 5 2026
A DISSIPATING LINE OF SHOWERS AND STORMS WILL APPROACH LA CROSSE
WITHIN THE NEXT HOUR. STILL PLENTY OF QUESTIONS ON WHETHER IT
WILL EVEN REACH LA CROSSE OR NOT, SO JUST WENT VCTS.
WITH ALL OF THE ADDITIONAL CONDENSATION NUCLEI FROM THE
FIREWORKS IN THE VALLEY, DECIDED TO GO WITH DENSE FOG EARLY
THIS MORNING AT KLSE. IT SHOULD DISSIPATE THERE BY 05.14Z. WAS
NOT AS SURE AT KRST, SO WILL JUST MONITOR IT THERE.
AFTERNOON AND EARLY EVENING INSTABILITY SHOWERS AND STORMS MAY
IMPACT KRST. CONFIDENCE WAS NOT HIGH ENOUGH TO INCLUDE THEM IN
THE TAF AT THIS TIME.
ARX WATCHES/WARNINGS/ADVISORIES
WI...NONE.
MN...NONE.
IA...NONE.
UPDATE...JAR
DISCUSSION...JAR
AVIATION...BOYNE
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page