442
FXUS63 KARX 060742
AFDARX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
242 AM CDT MON JUL 6 2026
KEY MESSAGES
- SEASONABLE TEMPERATURES EXPECTED THROUGH WEDNESDAY WITH HIGHS IN
THE MIDDLE TO UPPER 80S.
- SLIGHTLY BELOW NORMAL TEMPERATURES TO END THE WORK WEEK.
- STORMS LIKELY (60-80%) LATE WEDNESDAY AFTERNOON THROUGH THE
OVERNIGHT. STORMS WILL BE CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL
WITH SOME POTENTIAL (10-40% CHANCE) FOR OVER AN INCH OF
RAINFALL NORTH OF I-90.
DISCUSSION
ISSUED AT 242 AM CDT MON JUL 6 2026
TODAY - TUESDAY: SEASONABLE TEMPERATURES, SMALL STORM CHANCES TUESDAY
A FAIRLY BENIGN PATTERN IS IN STORE TO BRING IN THE NEW WORK WEEK
WITH WEAK RIDGING AND MINIMAL MODIFICATION TO THE AMBIENT AIRMASS IN
PLACE FOR TODAY. AS A RESULT, WITH THE CLEAR SKIES OVERHEAD, LIGHT
WINDS AND SMALL DEWPOINT DEPRESSIONS EARLY THIS MORNING, CANNOT RULE
(20-30% CHANCE) OUT SOME FOG FORMATION IN BOTH RIVER VALLEYS AND
AREAS WEST OF THE MISSISSIPPI RIVER. WHERE FOG DOES FORM IT COULD BE
LOCALLY DENSE WITH VISIBILITIES OF 1/4 MILE IN SPOTS. HOWEVER,
ANY FOG THAT DOES FORM WILL LIKELY MIX OUT QUICKLY DURING THE
MORNING LEAVING MOSTLY CLEAR SKIES FOR THE AFTERNOON HOURS. WILL
HAVE TO WATCH IF ANY REMNANT PRECIPITATION CAN SNEAK INTO THE
AREA DURING THE LATE EVENING HOURS AS A MID-LEVEL SHORTWAVE
PUSHES THROUGH CENTRAL MN. MUCH OF THE CAMS GENERALLY AGREE ON
DECAYING CONVECTION ASSOCIATED WITH THIS WAVE PRIOR TO REACHING
THE LOCAL AREA DUE TO IT OUTRUNNING THE INSTABILITY AXIS.
HOWEVER, CANNOT FULLY RULE OUT (UNDER 10% CHANCE) SOME REMAINING
PRECIPITATION SNEAKING INTO SOUTHEAST MN LATE THIS EVENING.
AS WE HEAD INTO TUESDAY, THE MAIN FEATURE TO WATCH WILL BE A
SHORTWAVE THAT WILL PROGRESS THROUGH THE DAKOTAS AND INTO CENTRAL
MINNESOTA DURING THE LATE EVENING HOURS ON TUESDAY. AS THIS OCCURS,
SOME SHOWER AND STORMS CHANCES (10-30% CHANCE) ARE PRESENT NORTH OF
I-90 DURING THE LATE EVENING AS LINGERING INSTABILITY WOULD SUGGEST
SOME POTENTIAL FOR STORMS ACROSS CENTRAL MN TO PERSIST INTO
LOCATIONS NORTH OF I-90.
WEDNESDAY - THURSDAY: STORMS LIKELY WEDNESDAY AFTERNOON AND INTO
OVERNIGHT, LOCALLY HEAVY RAINFALL POSSIBLE
THE LARGER IMPLICATION OF HOW STORMS EVOLVE ON TUESDAY AND INTO
TUESDAY NIGHT WILL BE HOW THESE STORMS MODIFY THE THERMAL GRADIENT
FOR STORM DEVELOPMENT ON WEDNESDAY. CURRENTLY, DETERMINISTIC
GUIDANCE WOULD SUGGEST A FRONTAL BOUNDARY THAT SETS UP SOMEWHERE IN
THE NORTH-CENTRAL WI VICINITY AS AN UPPER-LEVEL SHORTWAVE
TRANSVERSES THROUGH THE REGION DURING THE AFTERNOON THROUGH THE
OVERNIGHT HOURS ON WEDNESDAY. AS THIS OCCURS, 850MB MOISTURE
TRANSPORT IS PROGGED IN THE GFS TO RUN SOMEWHAT PERPENDICULAR TO THE
FRONT SUGGESTING A MADDOX FRONTAL PATTERN SETUP WITH THE DEEP-
LAYER SHEAR VECTOR RUNNING PARALLEL TO THE AFOREMENTIONED
BOUNDARY. THE KEY QUESTION OUTLINED BETWEEN THE GFS/EC IS THE
EXACT LOCATION OF WHERE THIS SETUP TAKES PLACE.
CURRENTLY, PROBABILISTIC GUIDANCE IN THE NBM GENERALLY KEEPS THE
HIGHEST PROBABILITIES FOR AN INCH OF RAINFALL OR GREATER NORTH OF
THE LOCAL AREA IN NORTHERN WI WITH ONLY LOWER PROBABILITIES
(10-40%) FOR AN INCH OR GREATER OF RAINFALL DURING THIS PERIOD
IN CLARK AND TAYLOR COUNTIES. THAT BEING SAID, THE 90TH
PERCENTILE OF THE NBM ACROSS PORTIONS OF TAYLOR COUNTY HAS
RAINFALL AMOUNTS IN THE 2-3" RANGE. SO WHILE MOST MEMBERS KEEP
THE HEAVIEST RAIN NORTH OF THE AREA, THE HIGHER PERCENTILE
SOLUTIONS WOULD SUGGEST A SCENARIO WHERE THE TUESDAY AND TUESDAY
NIGHT CONVECTION PUSHES THE THERMAL GRADIENT SOUTH. AS FAR AS
ANY SEVERE POTENTIAL, CANNOT FULLY RULE OUT SOME STRONG TO
LOCALLY DAMAGING WIND GUSTS WITH ANY STORMS IF COLD POOL
ORGANIZATION CAN TAKE PLACE. HOWEVER, GIVEN FAIRLY WEAK FLOW
ALOFT AND VERY WARM CLOUD DEPTHS, THE HAIL RISK IS EXTREMELY LOW
WITH ANY STORMS. IN ANY CASE, PROBABILITIES FOR SHOWERS AND
STORMS IN THE NBM ARE QUITE HIGH (70-90%) DURING THIS PERIOD
ACROSS MUCH OF THE AREA. CONSEQUENTLY, WHILE STORMS ARE LIKELY
ACROSS THE AREA, CONFIDENCE IN THE HEAVY RAIN RISK REMAINS LOW
AT THIS POINT.
FRIDAY - THIS WEEKEND: STARTING COOLER THAN NORMAL, WARMER SUNDAY
AS WE HEAD INTO FRIDAY, SLIGHTLY COOLER TEMPERATURES THAN
NORMAL TEMPERATURES SEEM PLAUSIBLE IN THE WAKE OF THE MID-WEEK
PRECIPITATION AS NORTHWESTERLY FLOW GETS ESTABLISHED ACROSS THE
LOCAL AREA ALOFT. HOWEVER, WOULD EXPECT SOMEWHAT OF A WARM UP AS
DETERMINISTIC GUIDANCE UNIFORMLY AGREES ON DEVELOPING A
PRONOUNCED UPPER-LEVEL HIGH PRESSURE CENTER OVER THE CENTRAL
PLAINS OVER THE WEEKEND. CONSEQUENTLY, SEEING MINIMAL
PRECIPITATION CHANCES ACROSS GUIDANCE AT THIS POINT WITH
SUBSIDENCE BUILDING INTO THE REGION AS A RESULT OF THIS UPPER-
LEVEL RIDGING.
AVIATION /06Z TAFS THROUGH 06Z TUESDAY/
ISSUED AT 1216 AM CDT MON JUL 6 2026
TRICKY FOG FORECAST FOR TONIGHT AT KLSE AS THE RAP HAS BEGUN TO
SUGGEST AN INCREASING LOW-LEVEL WIND FIELD LATER TONIGHT JUST OFF
THE SURFACE. HAVE OPTED TO KEEP WITH IFR REDUCTIONS AT KLSE WITH THE
06Z TAF ISSUANCE, HOWEVER IF THIS SCENARIO PRESENTED IN THE RAP DOES
BECOME REALITY THEN THIS WOULD MAKE IFR/LIFR FOG AT KLSE
UNLIKELY. AS FAR AS AREAL FOG TO IMPACT KRST, SEEING MIXED
SIGNALS IN GUIDANCE AS THE HREF HAS LOW PROBABILITIES (20-30%)
FOR VSBY REDUCTIONS, HOWEVER THE SIGNAL IN THE HREF IS IF FOG
DOES OCCUR IT WOULD LIKELY BE LIFR TO 1/4SM. HAVE OPTED TO HOLD
WITH SOME CATEGORY VSBY REDUCTIONS AND WILL ADJUST AS NEEDED
OVERNIGHT AT KRST. OTHERWISE, VFR CONDITIONS ARE EXPECTED
THROUGHOUT THE DAYTIME HOURS WITH FEW TO SCT DIURNAL CUMULUS
DURING THE AFTERNOON.
ARX WATCHES/WARNINGS/ADVISORIES
WI...NONE.
MN...NONE.
IA...NONE.
DISCUSSION...NAYLOR
AVIATION...NAYLOR
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page