335
FXUS63 KMKX 211100
AFDMKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
600 AM CDT FRI AUG 21 2026
KEY MESSAGES
- SHOWERS AND THUNDERSTORMS (NON-SEVERE) ARE LIKELY FOR EAST
CENTRAL WI THIS MORNING, WITH A CHANCE ELSEWHERE.
- SCATTERED SHOWERS AND THUNDERSTORMS (30 TO 50 PERCENT CHANCES)
WITH PASSING COLD FRONT ARE EXPECTED THIS AFTERNOON AND
EVENING. DAMAGING WINDS ARE THE MAIN THREAT.
- SMALL CHANCES (20 TO 40 PERCENT) FOR A SHOWER OR STORM
SATURDAY AFTERNOON FOR PORTIONS OF EAST CENTRAL AND SOUTHEAST
WISCONSIN.
UPDATE
ISSUED 600 AM CDT FRI AUG 21 2026
THE ONGOING SHOWERS AND THUNDERSTORMS OVER CENTRAL WI ARE
FOCUSED ALONG THE NOSE OF THE LOW LEVEL JET AND 700MB MOISTURE
AXIS. THERE IS ALSO WEAK 500MB VORTICITY ADVECTION AND A COUPLED
UPPER JET FEATURE. THE EXPECTATION IS THAT THE STORMS COULD
EXPAND SOUTHWARD INTO PORTIONS OF SOUTH CENTRAL WI (BUT NORTH OF
MADISON) THIS MORNING, BUT ALSO GRADUALLY DIMINISH AS THEY
APPROACH LAKE MICHIGAN DUE TO THE LLJ WEAKENING. THE AXIS OF
MUCAPE GREATER THAN 500 J/KG IS ON THE TAIL END OF THESE STORMS,
FROM JUNEAU/ADAMS COUNTIES TO LA CROSSE, SO THE STORMS ARE NOT
OVERLY STRONG.
WINDS WILL BE STEADY OUT OF THE SOUTHWEST TODAY, AND WE CAN
EXPECT AN INCREASE IN THE DEWPOINTS DUE TO MOISTURE ADVECTION
THIS AFTERNOON. THIS WILL HELP INCREASE OUR INSTABILITY,
ESPECIALLY IF WE GET PLENTY OF SUNSHINE BEHIND THE MORNING
CONVECTION. ISOLATED TO SCATTERED STORMS SHOULD DEVELOP OVER
SOUTH CENTRAL WI BY MID AFTERNOON. THE TRIGGER POINT FOR THESE
IS A LITTLE UNCERTAIN, AS WE WILL HAVE AN UPPER TROUGH OVERHEAD
WITH WEAK VORTICITY ADVECTION AND THEN A SURFACE TROUGH
APPROACHING.
NEVERTHELESS, WITH UP TO 2000 J/KG OF CAPE AND BULK SHEAR OF 20
TO MAYBE 30 KT, A FEW STRONG TO SEVERE STORMS ARE POSSIBLE THIS
AFTERNOON AND EVENING. DAMAGING WINDS ARE THE MAIN THREAT, BUT
WITH LOWER- END SEVERE POTENTIAL OF GUSTS UP TO 60 MPH. HAIL IS
POSSIBLE BUT WITHOUT THE BALANCED INSTABILITY/SHEAR ENVIRONMENT
IT WILL BE DIFFICULT TO SUSTAIN AN UPDRAFT. THE TORNADO
POTENTIAL IS NON- ZERO, BUT ALSO SEEMS PRETTY SMALL. THE 0-3KM
SHEAR VECTORS ARE ONLY AROUND 20 KT, BUT ANY LOCALIZED
BOUNDARIES (OUTFLOW, SURFACE FRONT, LAKE BREEZE, ETC.) COULD
HELP INCREASE THAT SPEED. THE CONDITIONS ARE SEEMING FAVORABLE
ENOUGH FOR SPC TO UPGRADE MOST OF SOUTHERN WI AND NORTHERN IL
INTO A SLIGHT RISK FOR SEVERE STORMS.
CRONCE
SHORT TERM
ISSUED 1100 PM CDT THU AUG 20 2026
TONIGHT THROUGH SATURDAY NIGHT:
TONIGHT SHOULD REMAIN LARGELY QUIET OUTSIDE OF A FEW LIGHT
SHOWERS NUDGING INTO THE REGION BUT DESPITE SOME PVA PUSHING
THROUGH AND LOW LEVEL WAA THE LOW LEVEL MOISTURE MAY BE TOO DRY
INITIALLY TO BRING SHOWERS TO THE GROUND. AROUND DAYBREAK
FRIDAY WE EXPECT SOME LOW LEVEL MOISTURE TO ALLOW FOR PRECIP
CHANCES TO INCREASE FOR A BRIEF PERIOD IN THE MORNING. THE
FORCING APPEARS TO BE LARGELY FOCUSED ALONG THE SHORTWAVE WITH
SUPPLEMENTARY WAA AND BETTER MOISTURE BUT CAMS DO NOT SEEM TO
FAVOR WIDESPREAD SHOWERS IN THE MORNING WITH BETTER CHANCES
FOCUSED FURTHER WEST CLOSER TO THE SURFACE FRONT. AS THE FRONT
PUSHES EAST MOISTURE SEEMS TO IMPROVE INTO FRIDAY AFTERNOON AND
EVENING. CAMS SEEM TO FAVOR SOME DEVELOPMENT OF CONVECTION
FRIDAY LATE AFTERNOON ON THE WESTERN HALF OF THE CWA WITH A
SECONDARY DEVELOPMENT POTENTIAL INTO THE EARLY EVENING CLOSER TO
THE LAKE. GIVEN HIGHER INSTABILITY (>2000 J/KG) AND ENOUGH
SHEAR (30-35KTS) WE SHOULD SEE A STRONGER STORM OR TWO FOR A
BRIEF PERIOD BUT THE LACK OF BETTER SHEAR SHOULD LIMIT THE
POTENTIAL TO JUST A FEW STORMS AT MOST WITH THE PRIMARY CONCERNS
BEING 1 INCH HAIL AND BRIEF DAMAGING WINDS.
QUIETER CONDITIONS OVERNIGHT FRIDAY INTO SATURDAY MORNING AS THE
SURFACE LOW PUSHES OUT. HOWEVER, SATURDAY LATE MORNING AND
AFTERNOON WE WILL LIKELY SEE A BACKDOOR COLD FRONT COMBINED WITH
LAKE BREEZE CONVERGENCE ZONE IN THE NEARSHORE REGION BRING
ADDITIONAL PRECIP CHANCES FOR EASTERN PORTIONS OF THE CWA. THERE
IS SOME UNCERTAINTY FOR THIS PRIMARILY WITH RESPECT TO LOW TO
MID LEVEL MOISTURE AND HOW WIDESPREAD IT WILL BE BUT SOME
SHOWERS AND PERHAPS A FEW STORMS WILL BE POSSIBLE WITH THIS. IF
WE CAN MANAGE A FEW STORMS WE COULD SEE SOME BECOME STRONG
GIVEN A DECENT AMOUNT OF DEEP LAYER SHEAR THOUGH THIS DIFFERS
SIGNIFICANTLY BETWEEN THE CAMS AND SYNOPTIC SCALE MODELS SO WE
WILL HAVE TO MONITOR THOSE CONDITIONS THROUGH FRIDAY. THIS WILL
BE WORTH MONITORING SATURDAY AFTERNOON GIVEN SOME POTENTIALLY SNEAKY
CONDITIONS. CHANCES WILL RAPIDLY DECREASE SATURDAY EVENING AS
WE LOSE INSTABILITY AND FORCING PUSHES OUT.
KUROSKI
LONG TERM
ISSUED 1100 PM CDT THU AUG 20 2026
SUNDAY THROUGH FRIDAY:
SUNDAY AND MONDAY WILL FEATURE HIGH PRESSURE BUILDING INTO THE
REGION KEEPING THINGS DRY THROUGH MONDAY. THINGS HAVE TRENDED
OVERALL DRIER INTO TUESDAY WITH THE HIGH PRESSURE LINGERING A
BIT LONGER WITH TUESDAY NIGHT WEDNESDAY BECOMING OUR NEXT BEST
CHANCE FOR SHOWERS AND STORMS AS AND 850MB FRONT AND UPPER LEVEL
SHORTWAVE SWING THROUGH WITH SOME WAA. STILL SOME UNCERTAINTY
IN TRACK AND TIMING BUT MODELS GENERALLY AGREE ON THIS PUSHING
THROUGH BRINGING PRECIP WITH LIKELY SOME STORMS AS WELL. IN
ADDITION, DEEP LAYER SHEAR APPEARS TO BE STRONG IN THE 40-50KT
RANGE WHICH WOULD BRING SOME SEVERE RISK IF THE TIMING OF STORMS
IS INTO THE EVENING.
AFTER WEDNESDAY, UNCERTAINTY INCREASES QUITE A BIT THOUGH IN
GENERAL HIGHER PRESSURE SEEMS TO BE PUSHING IN WITH DRIER
CONDITIONS OVERALL MORE LIKELY.
KUROSKI
AVIATION
ISSUED 600 AM CDT FRI AUG 21 2026
STORMS (NON-SEVERE) ARE LIKELY FOR EAST CENTRAL WI, BUT ARE
LOOKING LESS LIKELY FOR SOUTH CENTRAL AND SOUTHEAST WI THIS
MORNING. CLOUD BASES IN ANY STORMS TOWARD CENTRAL WI COULD DROP
TO 2500FT, BUT WOULD BE AROUND 5000FT ELSEWHERE. LOOK FOR
STEADY SOUTHWEST WINDS ACROSS SOUTHERN WI TODAY WITH A GENERAL
LULL IN STORM ACTIVITY. THEN ISOLATED TO SCATTERED STORMS ARE
EXPECTED TO DEVELOP IN SOUTH CENTRAL WI MID AFTERNOON AND TREK
EASTWARD THROUGH EARLY EVENING. A FEW STRONG TO SEVERE STORMS
ARE POSSIBLE WITH DAMAGING WINDS THE MAIN THREAT. WINDS WILL
BECOME NORTHWEST THIS EVENING AFTER THE PASSAGE OF A COLD FRONT.
CRONCE
MARINE
ISSUED 600 AM CDT THU AUG 20 2026
SOUTH TO SOUTHWEST WINDS WILL INCREASE TODAY AS A LOW PRESSURE
TROUGH OF 29.8 INCHES APPROACHES SOUTHERN WISCONSIN FROM THE
MINNESOTA ARROWHEAD. THUNDERSTORMS ARE EXPECTED AT TIMES TODAY
THROUGH TONIGHT. THE TROUGH WILL CROSS LAKE MICHIGAN FROM NORTH
TO SOUTH TONIGHT AND BRING A WIND SHIFT TO THE NORTHWEST. THEN LOOK
FOR GUSTY NORTHERLY WINDS TO DEVELOP ALONG A COLD FRONT THAT WILL
TRACK FROM NORTH TO SOUTH DOWN LAKE MICHIGAN SATURDAY EVENING. A
FEW THUNDERSTORMS ARE POSSIBLE ALONG THIS FRONT. NORTHERLY WINDS
WILL PERSIST THROUGH SUNDAY AS LOW PRESSURE AROUND 29.6 INCHES
TRACKS FROM LOWER MICHIGAN TO ONTARIO. VARIABLE WINDS ARE
EXPECTED FOR MONDAY AND TUESDAY AS HIGH PRESSURE OF 30.1 INCHES
CROSSES THE UPPER GREAT LAKES.
CRONCE
MKX WATCHES/WARNINGS/ADVISORIES
WI...NONE.
LM...NONE.
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