939
FXUS63 KIWX 021736
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
136 PM EDT SUN AUG 2 2026
KEY MESSAGES
- A FLOOD WATCH REMAINS IN EFFECT FOR PORTIONS OF NORTHERN
INDIANA AND NORTHWEST OHIO UNTIL 5 PM EDT THIS EVENING.
MODERATE TO HEAVY RAIN SHOWERS AND THUNDERSTORMS COULD BE SLOW
MOVING OR REPEATEDLY FORM OVER THE SAME AREA TODAY,
POTENTIALLY CAUSING FLOODING. THE GREATEST CONCERN FOR
ISOLATED FLOODING IS EAST OF INTERSTATE 69 ACROSS FAR
NORTHEAST INDIANA AND NORTHWEST OHIO.
- DANGEROUS SWIMMING CONDITIONS ARE EXPECTED AT
LAKE MICHIGAN BEACHES ALONG THE LA PORTE COUNTY, IN AND
BERRIEN COUNTY, MI SHORELINE TODAY AND TONIGHT. LIFE-
THREATENING WAVES AND CURRENTS ARE EXPECTED, ESPECIALLY THIS
AFTERNOON AND TONIGHT. A BEACH HAZARDS STATEMENT IS IN EFFECT.
FOR DETAILS, VISIT WWW.WEATHER.GOV/GREATLAKES/BEACHHAZARDS
- MOSTLY DRY CONDITIONS TONIGHT INTO WEDNESDAY. HIGHS WILL BE IN
THE UPPER 70S AND LOW TO MID 80S, WARMEST WEDNESDAY. CHANCES
FOR SHOWERS AND STORMS RETURN WEDNESDAY NIGHT AND PERSIST INTO
THE WEEKEND. THE BEST POTENTIAL (30-60 PERCENT) WILL BE
WEDNESDAY NIGHT INTO THURSDAY, THEN LOWER CHANCES (20 TO 40
PERCENT) PERSIST INTO THE WEEKEND. HIGHS WILL BE IN THE 80S
THURSDAY INTO THE WEEKEND, WARMEST SUNDAY.
UPDATE
ISSUED AT 1112 AM EDT SUN AUG 2 2026
THE SLOW MOVING UPPER LOW CENTER ACROSS SOUTHEAST INDIANA WILL
CONTINUE TO SAG SOUTH ACROSS KENTUCKY THIS AFTERNOON. A MID
LEVEL DEFORMATION AXIS EXTENDING TO THE NORTH ACROSS FAR
NORTHEAST INDIANA AND NORTHWEST OHIO HAS BEEN A FOCAL POINT FOR
SHOWERS BECOMING ANCHORED IN SAME LOCATIONS THIS MORNING, WITH
RADAR ESTIMATES OF 2 TO 4 INCHES OF RAIN INCLUDING SOUTHEAST
SIDE OF FORT WAYNE AND INTO PORTIONS OF NORTHWEST OHIO INCLUDING
PAULDING/DEFIANCE/WILLIAMS/FULTON COUNTIES. A VORT MAX DROPPING
SOUTHEAST FROM THE NORTHERN GREAT LAKES AND ASSOCIATED UPPER
SPEED MAX SHOULD ALLOW FOR SOME SLIGHTLY BETTER PROGRESSION OF
THIS WEAKENING DEFORMATION AXIS THIS AFTERNOON AS IT BEGINS TO
SLIDE SOUTHEAST. STILL CANNOT RULE OUT SOME ISOLATED INSTANCES
OF FLOODING, PARTICULARLY THROUGH 18Z ACROSS NW OHIO AND INTO
PORTIONS OF IN SOUTH OF US 24, BUT OVERALL THREAT SHOULD BE
SUBSIDING THIS AFTERNOON. THE FLOOD WATCH HAS BEEN CANCELLED ON
ITS WESTERN PERIPHERY FOR SOME IN COUNTIES. NO SIGNIFICANT
CHANGES TO THE FORECAST ARE ANTICIPATED AT THIS TIME.
DISCUSSION
ISSUED AT 301 AM EDT SUN AUG 2 2026
CANCELLED THE FLOOD WATCH EARLY FOR PORTIONS OF NORTHERN IN AS MOST
OF THE HIGH-RES GUIDANCE HAS BACKED OFF ON THE HIGHER RAINFALL
TOTALS IN THOSE AREAS. OTHERWISE, THE DEFORMATION ZONE ASSOCIATED
WITH THE UPPER LOW/TROUGH (WHICH ARE PRESENTLY OCCURRING WHERE WE
DIDN'T GET AS MUCH PRECIPITATION EARLIER TODAY) MOVES THROUGH. A
SHORTWAVE WILL DROP SOUTH ACROSS LAKE MI/LOWER MI AROUND 18-00Z
BEFORE THE UPPER RIDGE MOVES IN AND PUTS AN END TO PRECIP CHANCES.
SURFACE WINDS SHIFT FROM MORE NORTHEAST TO N-NW BEHIND THIS FEATURE
NEAR THE LAKE, WITH AN AREA OF CONVERGENCE DEVELOPING. HAVE POPS
PERSISTING THROUGH THE DAY, WITH AROUND 20-50 PERCENT NORTHWEST AND
THEN 60-90 PERCENT ALONG/SOUTH OF US 24. THE ENVIRONMENT SUPPORTS
EFFICIENT RAIN-PRODUCING CELLS, SO IF THERE ARE STORMS THAT END UP
REDEVELOPING/TRAINING OVER THE SAME AREA OR THERE ARE CELLS THAT
REMAIN FAIRLY STATIONARY FOR LONGER PERIODS OF TIME AS THE BROADER
SURFACE LOW/TROUGH MEANDERS E-NE, WE COULD END UP WITH SOME
LOCALIZED FLOODING. HIGH-RES GUIDANCE FOCUSES THE BEST POTENTIAL IN
NW OH AND PORTIONS OF NORTHERN INDIANA. KEPT THE WATCH GOING FOR THE
IN COUNTIES, AND THEN EXPANDED THE WATCH INTO NW OHIO IN
COLLABORATION WITH NWS CLE/DTX. AROUND AN INCH OR SO OF
PRECIPITATION HAS FALLEN IN MANY AREAS WITHIN THE WATCH, AND AN
ADDITIONAL 1 TO 2 INCHES IS EXPECTED THROUGH THE DAY (OF COURSE,
LOCALLY HIGHER AMOUNTS POSSIBLE).
WITH THE TROUGH SINKING DOWN THIS AFTERNOON, PRESENT NNE FLOW SHIFT
MORE N-NW FOR A PERIOD ON LAKE MICHIGAN. WAVES ARE PRESENTLY AT
AROUND 2-4 FEET, LOWEST UP NEAR SOUTH HAVEN, MI WHERE WAVE PERIODS
ARE ABOUT 4 SECONDS. FURTHER SOUTH NEAR MICHIGAN CITY, WAVES ARE
GREATEST WITH LONGER PERIODS OF AROUND 6 SECONDS. YESTERDAY
AFTERNOON/EVENING, WAVES AT MICHIGAN CITY GOT UP TO AROUND 5 FEET,
AND AROUND 4 FEET NEAR WARREN DUNES, MI. NORTHERN BERRIEN (INCLUDING
SILVER BEACH IN ST. JOSEPH, MI) AND THE SOUTH HAVEN AREA (BUOY
45168) LINGERED AROUND 2 FEET. WE ARE IN THE 'LULL-PERIOD' WHERE
WAVES MAY BRIEFLY DROP EARLY THIS MORNING INTO THE FIRST PART OF THE
DAY, BUT EXPECT THEM TO REACH HEIGHTS OF 4 TO 7 FEET AS THE FLOW
BECOMES MORE ONSHORE (VS SOMEWHAT SHORE PARALLEL). WAVE PERIODS
BEGIN TO LENGTHEN TO MORE LIKE 6-8 SECONDS BY LATE AFTERNOON AND
EARLY EVENING, ESPECIALLY FURTHER SOUTH. WILL PERSIST WITH THE
CURRENT MARINE HEADLINES WHERE SOUTHERN BERRIEN COUNTY, MI AND LA
PORTE COUNTY, IN ARE IN A BEACH HAZARDS STATEMENT ALL DAY TODAY AND
CONTINUING INTO MONDAY MORNING. NORTHERN BERRIEN COUNTY, MI
(INCLUDING SILVER BEACH IN ST. JOSEPH, MI) WILL BE MOSTLY MODERATE
SWIM RISK CONDITIONS UNTIL 5 PM EDT, WHEN WINDS AND WAVES PICK UP.
HAVE THE BEACH HAZARDS STATEMENT STARTING AT THAT TIME AND
PERSISTING THROUGH MONDAY MORNING. THE SMALL CRAFT ADVISORY FOR THE
MARINE ZONES REMAINS THE SAME AS WELL, WITH WINDS/WAVES DROPPING
BELOW CRITERIA AROUND 5 AM EDT.
EXPECT A STRONG LONGSHORE CURRENT MOVING FROM N TO S ALONG THE
SHORE, WITH STRONG STRUCTURAL CURRENTS EXPECTED (PARTICULARLY ON THE
NORTH SIDES OF PIERS AND BREAKWALLS). RIP CURRENTS ARE EXPECTED
GIVEN INCREASING WAVE HEIGHTS AND LENGTHENING WAVE PERIODS,
ESPECIALLY THIS AFTERNOON WHEN WINDS/WAVES BECOME MORE DIRECTLY
ONSHORE (VS MORE OBLIQUE OR SHORE-PARALLEL AS THEY ARE THIS
MORNING). WAVE HEIGHTS DIMINISH LATE TONIGHT/EARLY MON AM TOWARDS
AROUND 2-3 FEET, BUT WAVE PERIODS REMAIN AROUND 6-7 SECONDS THROUGH
EARLY MONDAY AFTERNOON. KEPT THE BH.S END TIME AT 8 AM MON, WITH A
MODERATE SWIM RISK FORECAST FOR ALL BUT NORTHERN BERRIEN COUNTY, MI
DURING THE DAY ON MONDAY. BY THE AFTERNOON, WAVES SHOULD BE ONLY
AROUND 1-2 FEET.
MOSTLY DRY CONDITIONS TONIGHT INTO WEDNESDAY WITH AN UPPER
RIDGE/SURFACE HIGH IN PLACE. HIGHS WILL BE IN THE UPPER 70S AND LOW
TO MID 80S, WARMEST WEDNESDAY. CHANCES FOR SHOWERS AND STORMS RETURN
WEDNESDAY NIGHT AND PERSIST INTO THE WEEKEND AS A BROAD UPPER LEVEL
LOW MOVES ACROSS THE CANADIAN PRAIRIE AND INTO HUDSON BAY. THIS WILL
BRING A TROUGH AND COLD FRONT INTO THE CWA BY WED NIGHT-SINKING
SOUTHEASTWARD AND STALLING SOMEWHERE ACROSS OUR CWA INTO THURSDAY.
GUIDANCE IS ALL OVER THE PLACE FOR FRIDAY INTO THE WEEKEND, WITH
SOME SHIFTING THE BOUNDARY SOUTHEAST OUT OF OUR AREA AND OTHERS
BRINGING IN A SECONDARY TROUGH AXIS THAT KEEPS POTENTIAL FOR
PRECIPITATION GOING INTO THE WEEKEND. THE BEST POTENTIAL FOR
SHOWERS/STORMS (30-60 PERCENT) WILL BE WEDNESDAY NIGHT INTO
THURSDAY, THEN LOWER CHANCES (20 TO 40 PERCENT) PERSIST INTO THE
WEEKEND GIVEN MODEL DISCREPANCIES. HIGHS WILL BE IN THE 80S THURSDAY
INTO THE WEEKEND, WARMEST SUNDAY.
AVIATION /18Z TAFS THROUGH 18Z MONDAY/
ISSUED AT 135 PM EDT SUN AUG 2 2026
THE MAIN AREA OF VORTICITY ALLOWING THE RAINFALL ACROSS THE AREA
CONTINUES TO SHIFT EASTWARD THIS AFTERNOON AS ANOTHER SHORTWAVE
ENTERS THE AREA. THIS ALLOWS DRIER AIR TO ENTER THE AREA AND SO A
MODERATION BACK TO VFR IS EXPECTED WITHIN A FEW HOURS OF THE START
OF THE PERIOD AT FWA. SBN IS ALREADY THERE. GUSTY NORTH WINDS TODAY
DIMINISH OVERNIGHT AND BECOME LIGHTER AND OUT OF THE EAST FOR
MONDAY.
IWX WATCHES/WARNINGS/ADVISORIES
IN...BEACH HAZARDS STATEMENT THROUGH MONDAY MORNING FOR INZ103.
OH...NONE.
MI...BEACH HAZARDS STATEMENT THROUGH MONDAY MORNING FOR MIZ277.
BEACH HAZARDS STATEMENT FROM 5 PM EDT THIS AFTERNOON THROUGH
MONDAY MORNING FOR MIZ177.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EDT MONDAY FOR LMZ043-046.
UPDATE...MARSILI
DISCUSSION...MCD
AVIATION...ROLLER
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