946
FXUS63 KARX 161751
AFDARX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
1251 PM CDT MON JUN 16 2025
KEY MESSAGES
- STRONG TO SEVERE STORMS THIS EVENING AND TONIGHT. HIGHEST
CONFIDENCE WEST OF THE MISSISSIPPI RIVER VALLEY, PRIMARY
HAZARDS OF DAMAGING WIND AND LARGE HAIL.
- ADDITIONAL STORM CHANCES TUESDAY THROUGH WEDNESDAY AND EARLY
FRIDAY INTO SATURDAY MORNING.
- WARM WEEKEND ON TAP.
DISCUSSION
ISSUED AT 146 AM CDT MON JUN 16 2025
MAIN FORECAST CONCERN CONTINUES TO BE SEVERE STORM THREAT LATER
TODAY. ONGOING CONVECTION EARLY THIS MORNING WILL HELP DETERMINE
TIMING OF LOCAL SEVERE THREAT LATER TODAY. A COUPLE RECENT HRRR
RUNS (16.02Z, 01Z, 00Z) EXHIBITED AN EARLIER QLCS AFFECTING THE
FORECAST AREA THIS AFTERNOON-EVENING RESULTANT OF A DECREASE IN
MORNING CONVECTION. THE DECREASE ALLOWS AN UNSTABLE AIRMASS TO
BUILD LOCALLY, BETTER FUELING THE STORM POTENTIAL. THIS SCENARIO
WILL ALSO BE DEPENDENT ON EXACT LOCATION OF FRONTAL BOUNDARY
CAUSING CYCLOGENESIS ACROSS THE FORECAST AREA. WHILE THIS ISN'T
THE HIGHEST CONFIDENCE SCENARIO, IT COULD BE THE MOST SEVERE
SCENARIO AND THEREFORE SOMETHING TO MONITOR.
HIGHEST STORM CONFIDENCE THIS EVENING - TONIGHT:
ALIGNED WITH PREVIOUS FORECASTS, HIGHEST CONFIDENCE IN A LATER
SOLUTION INTO THE NIGHTTIME HOURS AS THE MAIN LOW LIFTS
NORTHEAST THROUGH NORTHERN MINNESOTA; SLOWLY DRAPING A WEST-
SOUTHWEST ORIENTED FRONTAL BOUNDARY SOUTHEAST THROUGH THE
FORECAST AREA. GIVEN THE LATER TIMING, THE HIGHEST SEVERE
THREAT WOULD BE FARTHER WEST CONCURRENT WITH PEAK DIURNAL
HEATING AND MORE UNSTABLE AIR; ALIGNING WITH ENHANCED RISK IN
SPC CONVECTIVE OUTLOOKS. SLIGHT RISK SEEN OVER LOCALLY WESTERN
COUNTIES IN NORTHEAST IOWA AND SOUTHEAST MINNESOTA. SPEED AND
TIMING OF CONVECTION WILL DIRECTLY AFFECT POTENTIAL CHANGES TO
THESE RISK LOCATIONS; I.E., EARLIER = FARTHER EAST.
HAZARDS & ACCOMPANYING TIMING IMPACTS:
WHILE CLOUDED BY LOCATION AND TIMING OF MESOSCALE FORCING,
AMPLE SEVERE PARAMETERS (CAPE/SHEAR) AWAIT CONVECTION. WITH
THIS EARLIER SOLUTION, THE MOST RECENT F48 HRRR (16.00Z)
INCREASED 0-6KM SHEAR FROM 30 TO 40 KTS. WHILE ALL HIGH
RESOLUTION MEMBERS SUGGEST INCREASE IN SHEAR OVER PREVIOUS RUNS,
MOST LIMIT IT POSTFRONTALLY OR IN MINUSCULE SPOTS OF MESOSCALE
INFLUENCE. ACCOMPANYING LONG HODOGRAPHS SUGGEST LARGE HAIL WILL
BE POSSIBLE AND DAMAGING WIND WITH INCREASED LOW LEVEL FLOW.
OVERALL TORNADO THREAT IS QUITE CONDITIONAL ON /IF/ THE EARLIER
QLCS TAKES SHAPE. THE EARLIER SOLUTION IN THE AFOREMENTIONED
HRRR RUNS WOULD INCREASE THIS POSSIBILITY WHILE PREVIOUS RUNS
AND OTHER MODELS WITH A LATER SOLUTION LIMIT OVERALL SURFACE
BASED ACTIVITY.
SUBSEQUENT STORM THREAT TUESDAY:
SUBSEQUENT STRONG STORM THREAT EXPECTED TO AFFECT THE LOCAL
FORECAST AREA TUESDAY, TUESDAY NIGHT, AND/OR WEDNESDAY MORNING.
UNFORTUNATELY CONFIDENCE IS LOW DUE TO TODAY/TONIGHT'S STORM
TIMING AND RESULTANT FRONTAL LOCATION. THE EARLIEST SOLUTION
(LOWEST CONFIDENCE) WOULD RESULT FROM A STRONG, LINEAR STORM
MODE TONIGHT, ALLOWING INSTABILITY TO BUILD FARTHER NORTH
THROUGH TUESDAY. CURRENT CONFIDENCE KEEPS FRONTAL BOUNDARY TO
THE SOUTH, ADVECTING HIGHEST STORM CHANCES ZONALLY ALONG
SOUTHERN HALF OF THE FORECAST AREA.
STORM CHANCES WEDNESDAY:
FURTHERMORE, THE EXIT OF TONIGHT'S LOW AFFECTS SUBSEQUENT
SYNOPTIC SOLUTIONS FOR WEDNESDAY. A SURFACE LOW EXPECTED TO
LIFT NORTHEAST ALONG A SOUTHWEST-NORTHEAST ORIENTED BAROCLINIC
BOUNDARY FROM THE SOUTHERN TO CENTRAL PLAINS; ADVECTING THE
LINGERING FRONTAL BOUNDARY NORTH ACROSS THE FORECAST AREA. LREF
SOLUTIONS WHICH HAVE EXHIBITED SLIGHT VARIATIONS OVER THE LAST
COUPLE OF RUNS: AGREEING ON A SLIGHTLY SLOWER SOLUTION THROUGH
WEDNESDAY MORNING, POTENTIALLY PROVIDING SOME MORE UNSTABLE AIR
FARTHER NORTH. ALTHOUGH, THE EPS HAS STRENGTHENED THE LOW WHILE
THE GEFS HAS WEAKENED, GOING TO SHOW THE COPIOUS DETAILS REQUIRING
IRONING OUT. REGARDLESS, BETTER SHEAR WILL LIE POSTFRONTALLY TO
THE NORTH.
STORM CHANCES FRIDAY INTO SATURDAY:
EVENTUALLY MID LEVEL HEIGHTS BUILD (LREF 100% CONFIDENCE) THROUGH
THURSDAY, REDUCING WIDESPREAD PRECIPITATION POTENTIAL INTO THE
WEEKEND. PRECIPITATION POTENTIAL WILL GRAZE NORTHERN PERIPHERAL
COUNTIES IN CENTRAL WISCONSIN AS A LOW ADVECTS ZONALLY ALONG
THE INTERNATIONAL BORDER FRIDAY INTO SATURDAY.
WARMING THROUGH THE WEEKEND:
BUILDING HEIGHTS THROUGH THE END OF THE WEEK (LREF 100%
CONFIDENCE) INCREASES SURFACE TEMPERATURES THROUGH THE WEEKEND.
THE WARMEST SOLUTIONS SEEN IN THE EPS AND GEPS WITH 60-100%
CONFIDENCE FOR THE 80 DEGREE ISOTHERM ENVELOPING THE FORECAST
AREA FRIDAY WARMING INTO THE UPPER 80S THROUGH THE WEEKEND. THE
GEFS ON THE OTHER HAND SUGGESTS A COLDER SOLUTION WITH 10-30%
FOR 80 DEGREES ON FRIDAY AND LOW 80S THROUGH THE WEEKEND. WILL
BE DEPENDENT ON THE STRENGTH AND WESTERN EXTENT OF THE BERMUDA
HIGH.
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
ISSUED AT 1245 PM CDT MON JUN 16 2025
MVFR CEILINGS EAST OF THE MISSISSIPPI RIVER SCATTER AND LIFT
THROUGH THE MID AFTERNOON TODAY. FOR THE REST OF THE AFTERNOON
AND EVENING, ANY RESTRICTIONS WILL BE TIED TO SEVERAL CLUSTERS
OF SHOWERS AND THUNDERSTORMS THAT MOVE THROUGH THE REGION.
CONFIDENCE IN THE LOCATION AND INTENSITY OF THESE STORMS IS ON
THE LOW SIDE DUE TO ONGOING STORMS WEST OF THE MISSISSIPPI
RIVER, BUT AREAS NORTH OF A RST TO ISW LINE HAVE THE BEST
THREAT OF SEEING ANY SEVERE STORMS THIS EVENING.
THE THREAT FOR THESE STORMS SHIFTS EAST AND SOUTH AFTER 06Z,
THOUGH THERE ARE SOME INDICATIONS OF MVFR STRATUS BUILDING EAST
OF THE MISSISSIPPI RIVER TOWARDS SUNRISE AND LIFTING DURING THE
MORNING. SOUTHEAST TO SOUTHWEST WINDS AT 10-15 KTS THIS
AFTERNOON VEER TO THE WEST LATE TONIGHT AND TO THE NORTHWEST AT
5-10 KTS FOR THE DAY ON TUESDAY.
ARX WATCHES/WARNINGS/ADVISORIES
WI...NONE.
MN...NONE.
IA...NONE.
DISCUSSION...JAR
AVIATION...SKOW
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page