752
FXUS63 KARX 171749
AFDARX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
1249 PM CDT WED JUN 17 2026
KEY MESSAGES
- SCATTERED SHOWERS AND STORMS INTO THE EVENING. SOME OF THESE
STORMS COULD BE SEVERE, HOWEVER THIS DEPENDS ON WELL WE
RECOVER FROM THIS MORNING'S STORMS. LARGE HAIL AND DAMAGING
WINDS WILL CONTINUE TO BE THE MAIN THREATS WITH TORNADO THREAT
DEPENDENT ON AMOUNT OF DESTABILIZATION.
- LOW CONFIDENCE IN PRECIPITATION AND STORMS THURSDAY SLIGHTLY
INCREASES FOR FRIDAY AS TRANSIENT PRECIPITATION DARTS FROM
NORTHWEST TO SOUTHEAST.
DISCUSSION
ISSUED AT 848 AM CDT WED JUN 17 2026
SEVERE STORM CHANCES THROUGH TODAY:
DETAILS (I.E., STRENGTH, TIMING, COVERAGE) SURROUNDING ADDITIONAL
SUBSEQUENT STORM CHANCES THROUGH THE REST OF DAY DEPENDS ON
NORTHERN AND EASTERN EXTENT OF ENERGY CONSOLIDATION BETWEEN LOW
PRESSURE AREAS, EVIDENT IN DISAGREEMENT BETWEEN HIGH RESOLUTION
MODELS (17.00Z).
A MORE PHASED ORIENTATION BETWEEN LOW CENTERS THROUGH THE EARLY
MORNING BEFORE CONSOLIDATING INTO A STRONGER, ELONGATED LOW WOULD
RESULT IN A SOUTHERN SHUNT OF INCREASED MOISTURE, LIMITING /HIGHEST/
LOCAL OVERALL SEVERE THREAT (NAM/FV3 17.00Z).
HOWEVER, MORE HREF MEMBERS (HRRR/ARW 17.00Z) SOLUTIONS SUGGEST A
LESS-PHASED, MORE MERIDIONAL ORIENTATION AND INTERACTION BETWEEN
CONVERGING LOW LEVEL AREAS OF LOWER ISOHEIGHTS ALLOWING INCREASED
MOISTURE TO ADVECT FARTHER NORTH INTO THE FORECAST AREA, CAUSING
UNSTABLE AIR (1000-1500 J/KG SBCAPE) TO BIFURCATE THE SOUTHERN HALF
OF THE FORECAST AREA, INCREASING SEVERE STORM CHANCES THROUGH
THE AFTERNOON AND EVENING AS THE EVENTUAL LOW CENTER DRIVES
BREAKING LINEAR STORMS ACROSS THE FORECAST AREA.
ADDITIONAL STORMS THROUGH THE LATE MORNING INTO THE EARLY AFTERNOON
CANNOT BE RULED OUT AS WELL, SOME OF THESE COULD POTENTIALLY
BECOME SEVERE SHOULD THE PBL RECOVER /IF/ SKIES FIND A WAY TO
CLEAR IN THE WAKE OF DEPARTING STORMS. GIVEN THE MORNING
PRECIPTIATION, THIS IS A LOWER CONFIDENCE SCENARIO BUT AVAILABLE
INSTABILITY AND SHEAR VALUES SUGGEST A SCENARIO TO REMAIN
COGNIZANT OF THROUGH THE DAYTIME HOURS.
MAIN CONCERN FOR LARGE HAIL AND DAMAGING WINDS WITH LATER STORMS AS
WELL. TORNADO RISK WILL HINGE ON AMOUNT OF CLEARING TO DESTABILIZE
THE PBL, SUBSEQUENTLY OVERCOMING ANY LINGERING INVERSION CAUSING
SBCIN/MLCIN.
LOW CONFIDENCE FOR PRECIPITATION THURSDAY:
NORTHERN EXTENT OF INCREASED MOISTURE ADVECTION THROUGH EARLY
WEDNESDAY MORNING ALSO AFFECTS PRECIPITATION CHANCES THROUGH
THURSDAY AS HREF (17.00Z) ALLUDE TO LIMITED (100-300 J/KG) OF SBCAPE
ADVECTING SOUTHEAST ALONG THE SOUTHWEST-NORTHEAST ORIENTED FRONTAL
BOUNDARY WITH MEAGER LOW LEVEL (850MB) COLD AIR ADVECTION.
THEREFORE, HAVE INCREASED A LINE OF LOW POPS (<24%) AWAY FROM NBM
BASED ON HIGH RESOLUTION SOLUTIONS ALBEIT A BIT MORE SPATIALLY AND
TEMPORALLY AGREEABLE THAN INDIVIDUAL MEMBER SOLUTIONS.
FRIDAY PRECIPITATION CHANCES:
THE TAIL END OF THE EXTENDED RIBBON OF MID LEVEL POSITIVE VORTICITY
LIFTS SLIGHTLY NORTHEAST AS THE SYNOPTIC PATTERN BEGINS TO CHANGE,
CAUSING ADDITIONAL, ALBEIT TRANSIENT, PRECIPITATION AND STORM
CHANCES TO DART ACROSS THE FORECAST AREA FOR FRIDAY. LOW CONFIDENCE
IN STORMS AS MOST (75%) MEMBERS OF EPS (16.18Z) SUGGEST 500-1000
J/KG OF MUCAPE ACROSS THE AREA WHILE GEFS (17.00Z) LIMITS SBCAPE
BELOW 500 J/KG SOMEWHERE NEAR/OVER THE FORECAST AREA. ACCOMPANYING
SHEAR VALUES WILL BE SPATIALLY LIMITED IN THE LOWER LEVELS,
PRIMARILY AND STRONGEST UNIDIRECTIONALLY IN THE MID LEVELS FROM THE
STRONGER MID TO UPPER LEVEL WINDS.
AVIATION /18Z TAFS THROUGH 18Z THURSDAY/
ISSUED AT 1250 PM CDT WED JUN 17 2026
WIDESPREAD MVFR CEILINGS PERSIST THROUGH THE AFTERNOON WITH
POCKETS OF IFR CEILINGS DURING THE EVENING AND OVERNIGHT HOURS,
MAINLY AT HIGHER ELEVATION LOCATIONS. A LINE OF SHOWERS AND
STORMS MOVE THROUGH THIS AFTERNOON, DECREASING IN INTENSITY IN
THE EVENING. THESE CEILINGS LAST THROUGH THE OVERNIGHT AND LIFT
THROUGH THE MORNING ON THURSDAY. CURRENT SOUTHERLY WINDS AS OF
MIDDAY VEER TO THE WEST AND NORTHWEST BEHIND THE FRONT BRINGING
THESE STORMS WITH GUSTS OF 20-30KTS IN ITS WAKE. THESE WINDS
SLOWLY DECREASE OVERNIGHT TO 5-10KTS BY THURSDAY MORNING.
ARX WATCHES/WARNINGS/ADVISORIES
WI...NONE.
MN...NONE.
IA...NONE.
DISCUSSION...JAR
AVIATION...SKOW
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page