650
FXUS63 KARX 200502
AFDARX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
1202 AM CDT SAT JUN 20 2026
KEY MESSAGES
- ISOLATED SHOWERS MAY IMPACT TAYLOR AND NORTHERN CLARK
COUNTIES SATURDAY AFTERNOON (15% CHANCE).
- RAIN POTENTIAL ON SUNDAY INCREASES HEADING SOUTH FROM THE
IA/MN BORDER PARALLEL (30-60%), HIGHEST JUST SOUTH OF OUR
FORECAST AREA.
- VERY GOOD (60-80%) CHANCE FOR SHOWERS AND THUNDERSTORMS
TUESDAY INTO WEDNESDAY.
DISCUSSION
ISSUED AT 1202 AM CDT SAT JUN 20 2026
VERY SMALL CHANCE FOR A SHOWER NORTH OF I-94 SATURDAY
SATURDAY AFTERNOON, VERY WEAK UPPER DISTURBANCE MAY KICK OFF A
SHOWER NORTH OF I-94. LIMITING FACTOR ONCE AGAIN LOOKS TO BE
INSTABILITY AS MOST OF THIS AREA TURNED OVER FRIDAY EVENING AND LOW
LEVEL MOISTURE RECOVERY IS NOT EXPECTED. THUS, WHILE STRONG
UNIDIRECTIONAL SHEAR REMAINS IN PLACE WITH AN UPPER JET ALOFT,
ACTUALLY GETTING AN UPDRAFT TO TAP INTO THAT APPEARS DOUBTFUL. THIS
IS REFLECTED IN RECENT RUNS OF CAMS WHICH ALL DEPICT PRECIP
STRUGGLING TO DEVELOP. HAVE THEREFORE GONE WITH ONLY VERY LOW END
MENTIONS OF SHOWERS (15%).
WANING POTENTIAL FOR MODERATE RAIN IN NE IA, SW WI SUNDAY
UPPER WAVE CURRENTLY OVER NV LOOKS TO CONTINUE TO ROLL EASTWARD
THROUGH THE WEEKEND, FORCING LEE CYCLOGENESIS IN E CO WITH THIS
FEATURE MOVING EAST INTO CENTRAL IL UNDER THE LEFT EXIT REGION OF AN
UPPER JET ADVANCING OVER THE SOUTHERN PLAINS. ROBUST SOUTHERLY
MOISTURE ADVECTION WILL OCCUR ACROSS THE LOWER AND MID MISSISSIPPI
VALLEY AHEAD OF THIS LOW, LEADING TO ABUNDANT PRECIP ACROSS
MO/IA/IL. FIRST COUPLE GUIDANCE CYCLES AFTER THE DISTURBANCE MOVED
ONSHORE HAVE FOCUSED THE TRAJECTORY ALONG THE LINES OF SEVERAL
PREVIOUS RUNS OF THE OPERATIONAL GFS/EC, KEEPING RAIN JUST TO THE
SOUTH OF THE CWA. THAT SAID, STILL SOME ENSEMBLE MEMBERS BRINGING AT
LEAST SOME RAIN TO NE IA AND SW WI. HAVE THEREFORE ATTEMPTED TO
TIGHTEN THE NORTH TO SOUTH POP GRADIENT COMPARED TO NBM, REMOVING
MOST MENTIONS BETWEEN I-90 AND A PARALLEL DEFINED BY THE MN/IA
BORDER. IN ANY CASE, HAZARDS SEEM UNLIKELY AS THE 19.12Z LREF NOW
ONLY DEPICTS A 10-15% CHANCE FOR OUR FAR SOUTHERN COUNTIES TO REACH
EVEN 1" OF ACCUMULATION AND APPRECIABLE INSTABILITY REMAINS WELL TO
OUR SOUTH.
THUNDERSTORMS TUESDAY INTO WEDNESDAY
WHILE TIMING DIFFERENCES REMAIN, RATHER NOTABLE AGREEMENT ACROSS
GUIDANCE THAT A STRONG UPPER WAVE WILL DIVE SOUTHEAST OVER OR JUST
TO THE NORTHEAST OF THE CWA TUESDAY INTO WEDNESDAY, BRINGING
WIDESPREAD PRECIP. CONTINUED NORTHWESTERLY FLOW ALOFT FOLLOWING THE
PATTERN PAUSE THIS WEEKEND WILL LIMIT OPPORTUNITIES FOR STRONG MOIST
ADVECTION BUT, GIVEN COLD TEMPERATURES ALOFT, SHOULD SEE SOME
THUNDERSTORMS. ADDITIONALLY, WHILE UPPER WINDS ARE NOT AS STRONG AS
THEY WERE THIS PAST FRIDAY WHEN CONVECTION OVERACHIEVED IN SEVERITY,
MAY STILL SEE 40-50 KNOTS OF SHEAR. THEREFORE, WILL NEED TO CONTINUE
TO WATCH THIS PERIOD FOR ANOTHER LOWER END SEVERE THUNDERSTORM RISK
DAY.
AVIATION /00Z TAFS THROUGH 00Z SUNDAY/
ISSUED AT 623 PM CDT FRI JUN 19 2026
SHOWERS AND STORMS CONTINUE MOVING THROUGH THE REGION THIS
EVENING AS AN AREA OF LOW PRESSURE SHIFTS EASTWARD ACROSS
NORTHERN WISCONSIN. THESE SHOWERS/STORMS ARE EXPECTED TO MAINLY
IMPACT AREAS ALONG AND NORTH OF I-90, BRINGING MVFR/IFR
VISIBILITY AND MVFR CEILINGS, BEFORE MOVING OUT OF THE AREA BY
05Z. BEHIND THEM, VFR CONDITIONS ARE EXPECTED, CONTINUING
THROUGH THE OVERNIGHT AND INTO SATURDAY MORNING FOR MOST,
ALTHOUGH THOSE NORTH OF I-94 HAVE THE POTENTIAL TO SEE MVFR
CEILINGS DEVELOP THROUGH MID SATURDAY MORNING (40-60% PER THE
19.18Z REFS). GUSTY SOUTHWEST WINDS CONTINUE OVER THE NEXT FEW
HOURS, GENERALLY 20-30KT, BEFORE DIMINISHING TO LESS THAN 10KT
OVERNIGHT AND VEERING TO THE NORTHWEST SATURDAY MORNING.
ARX WATCHES/WARNINGS/ADVISORIES
WI...NONE.
MN...NONE.
IA...NONE.
DISCUSSION...FERGUSON
AVIATION...FALKINHAM
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