080
FXUS63 KIWX 172357
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
757 PM EDT FRI JUL 17 2026
KEY MESSAGES
- SMOKE FROM CANADIAN WILDFIRES WILL CONTINUE TO BRING PERIODS
OF POOR AIR QUALITY AND REDUCED VISIBILITY THROUGH AT LEAST
MONDAY.
- SLIGHT CHANCE FOR SEVERE STORMS SATURDAY AFTERNOON AND
EVENING. DAMAGING WINDS AND HEAVY DOWNPOURS WILL BE THE MAIN
THREATS.
- HIGH SWIM RISK CONDITIONS ARE EXPECTED ALONG LAKE MI BEACHES
IN BERRIEN COUNTY, MI AND LA PORTE COUNTY, IN BY LATE SATURDAY
AFTERNOON AND EVENING. MODERATE SWIM RISK CONDITIONS ARE
EXPECTED EARLIER IN THE DAY. DANGEROUS WAVES AND CURRENTS ARE
EXPECTED.
DISCUSSION
ISSUED AT 236 PM EDT FRI JUL 17 2026
CANADIAN WILDFIRE SMOKE WILL CONTINUE TO BRING MAJOR AIR
QUALITY IMPACTS TO THE GREAT LAKES REGION FOR THE NEXT SEVERAL
DAYS. EPA SENSORS ACROSS THE AREA HAVE BEEN SAMPLING VERY
UNHEALTHY TO HAZARDOUS PM2.5 DUE TO THE SMOKE. IT IS ADVISED TO
STAY INDOORS AS MUCH AS POSSIBLE IN THESE CONDITIONS. SHOWERS
AND THUNDERSTORMS, COUPLED WITH SOUTHWEST 850MB FLOW (THEN
BECOMING WEST TONIGHT), WILL HELP TO NUDGE THE SMOKE SLOWLY OFF
TO THE NORTHEAST AND EAST. THIS WILL BRING SOME RELIEF FOR
TOMORROW, BUT MOST AREAS ARE STILL EXPECTED TO REMAIN UNHEALTHY
FOR SENSITIVE GROUPS. AN UPPER LEVEL TROUGH MOVING THROUGH THE
GL TOMORROW NIGHT WILL RESTRENGTHEN THE SMOKE CONVEYER BELT, FOR
A LACK OF BETTER WORDS, AND SUNDAY WE COULD HAVE REINVIGORATED
SMOKE IMPACTS. MONDAY, WEAK LOW-LEVEL WINDS FROM HIGH PRESSURE
OVER LAKE ERIE WILL KEEP SUNDAY'S SMOKE HANGING AROUND.
UNFORTUNATELY, THE NICE BREAK FROM SEVERE WEATHER LOOKS TO COME
TO AN END. FOR TODAY, A MARGINAL RISK FOR SEVERE STORMS (STRONG
WINDS IS THE MAIN THREAT WHERE MIXED LAYER LAPSE RATES ARE THE
STRONGEST) WILL BE IN PLACE FOR AREAS GENERALLY FORT-WAYNE
SOUTHWARD. AS OF THIS WRITING, MORE ROBUST CONVECTION HAS
INITIATED OVER LAFAYETTE, IN AND THIS WILL CONTINUE TO WORK ITS
WAY EAST-NORTHEAST. THERE IS PLENTY OF INSTABILITY FOR SHOWER
AND THUNDERSTORM GROWTH TODAY, SO WE EXPECT A GOOD MAJORITY OF
THE CWA TO GET WETTING RAIN.
THE MID/UPPER LEVEL TROUGH THAT EVENTUALLY BRINGS MORE SMOKE
DOWN WILL BE MOVING THROUGH ONTARIO AND QUEBEC ON SATURDAY. A
COLD FRONT WILL DRAG SOUTH THROUGH THE DAY. AHEAD OF THIS, 850MB
FLOW WILL INCREASE TO AROUND 25-30KT AND CAPE VALUES ON THE
ORDER OF 2500-3000 J/KG WILL PROMOTE A LINE OF SHOWERS AND
THUNDERSTORMS PROPAGATING SOUTH AND SOUTHEAST THROUGH THE
AFTERNOON TO EARLY EVENING HOURS. WHILE DAMAGING WINDS WILL BE
THE PRIMARY THREAT, LOW-LEVEL HELICITY WILL BE MARGINALLY
ADEQUATE (75-100 M^2/S^2)) TO PRODUCE A QUICK SPIN-UP TORNADO.
THE GOOD NEWS IS THAT AFTER TOMORROW, WE CAN SAY GOODBYE TO
TEMPS IN THE 90S FOR THE UPCOMING WEEK AS WE RETURN TO A MORE
NORMAL TEMPERATURE PATTERN. ACTUALLY, WELL BELOW AVERAGE TEMPS
ARE EXPECTED ON WEDNESDAY-THURSDAY WITH TEMPS IN THE 70S. THIS
WILL BE IN THE WAKE OF A POTENT SYSTEM THAT WILL BRING THE
CHANCE FOR SEVERE WEATHER TO OUR AREA MONDAY AND TUESDAY AS THE
STORM PREDICTION CENTER HAS OUR AREA UNDER A D4/D5 SLIGHT RISK.
STAY TUNED TO SPC.NOAA.GOV FOR THE LATEST ON THAT.
AVIATION /00Z TAFS THROUGH 00Z SUNDAY/
ISSUED AT 749 PM EDT FRI JUL 17 2026
VFR CONDITIONS ARE EXPECTED AT THE TERMINALS FOR THE MOST PART,
OUTSIDE OF SOME MVFR HAZE/BR POTENTIAL LATE TONIGHT/EARLY SAT AM
AT KFWA. CHANCES FOR MVFR/IFR CEILINGS/VIS ARE POSSIBLE IN ANY
HEAVIER SHOWER OR THUNDERSTORM ACTIVITY SAT AFT/EVE FOR BOTH
SITES (KSBN EARLIEST). MODELS SUGGEST THAT THE THICKER SMOKE
WILL EXIT THE AREA AT LEAST THROUGH SAT AS FLOW STRENGTHENS OUT
OF THE S-SW. COULD SEE SOME GET TRAPPED BENEATH THE INVERSION
AT KFWA, OR AT LEAST SEE SOME BRIEF BR THIS MORNING BEFORE
SUNRISE. FOR HANDLED WITH A TEMPO BETWEEN 9-12Z AT KFWA.
OTHERWISE, A COLD FRONT WILL DROP FROM NORTH TO SOUTH THROUGH
THE AFTERNOON AND EARLY EVENING HOURS, WITH POTENTIAL FOR SEVERE
STORMS. HAVE PROB30S TO ACCOUNT FOR THIS GIVEN IT'S LATER IN THE
PERIOD, BUT HAVE KSBN POTENTIAL STARTING AS EARLY AS 15-18Z,
CONTINUING AS LATE AS 21Z AND KFWA STARTING AS EARLY AS 18Z,
CONTINUING THROUGH THE END OF THE PERIOD. MODELS DISAGREE ON THE
PACE OF THE FRONTS PROGRESSION THROUGH OUR AREA, THE EARLIEST
BEING THE RAP. SMOKE MAY FILTER BACK IN BEHIND THE FRONT AS
WINDS SHIFT N-NW THROUGH THE DAY/NIGHT.
IWX WATCHES/WARNINGS/ADVISORIES
IN...AIR QUALITY ALERT UNTIL MIDNIGHT EDT /11 PM CDT/ SATURDAY
NIGHT FOR INZ005>009-012>015-017-018-020-022>027-032>034-
103-104-116-203-204-216.
OH...AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR OHZ001-002-
004-005-015-016-024-025.
MI...AIR QUALITY ALERT UNTIL MIDNIGHT EDT SATURDAY NIGHT FOR
MIZ078>081-177-277.
MARINE...DENSE SMOKE ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LMZ043-
046.
DISCUSSION...NORMAN
AVIATION...MCD
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