WUCN11 CWTO 182333
YELLOW WARNING - SEVERE THUNDERSTORM
FOR SOUTHERN ONTARIO
UPDATED BY ENVIRONMENT CANADA
AT 7:33 P.M. EDT MONDAY 18 MAY 2026.
---------------------------------------------------------------------
YELLOW LEVEL WARNING - SEVERE THUNDERSTORM - FOR:
      STRATFORD - MITCHELL - SOUTHERN PERTH COUNTY
      LISTOWEL - MILVERTON - NORTHERN PERTH COUNTY
      MOUNT FOREST - ARTHUR - NORTHERN WELLINGTON COUNTY
      HANOVER - DUNDALK - SOUTHERN GREY COUNTY
      OWEN SOUND - BLUE MOUNTAINS - NORTHERN GREY COUNTY.

YELLOW LEVEL WARNING - SEVERE THUNDERSTORM - ENDED FOR:
      LONDON - PARKHILL - EASTERN MIDDLESEX COUNTY
      GODERICH - BLUEWATER - SOUTHERN HURON COUNTY
      WINGHAM - BLYTH - NORTHERN HURON COUNTY
      SAUGEEN SHORES - KINCARDINE - SOUTHERN BRUCE COUNTY
      BRUCE PENINSULA - SAUBLE BEACH - TOBERMORY.

---------------------------------------------------------------------
IMPACT LEVEL: MODERATE
FORECAST CONFIDENCE: HIGH

==DISCUSSION==

UPDATED OR ENDED BY 9:32 P.M. EDT.

AT 7:33 P.M. EDT, ENVIRONMENT CANADA METEOROLOGISTS ARE TRACKING A 
LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING STRONG WIND GUSTS.

THUNDERSTORM LOCATION: JOHNSON HARBOUR TO BIRR 

MOTION: MOVING EAST AT 70 KM/H 

HAZARDS: 
WIND: STRONG (UP TO 90 KM/H) 

LOCATIONS IN THE PATH: 
ETTRICK 
MONKTON 
ATWOOD 
LISTOWEL 
ST. MARYS 
PALMERSTON 
MOUNT FOREST 
MARKDALE 
THORNBURY 
DRAYTON

LOCAL UTILITY OUTAGES ARE LIKELY. DAMAGE TO ROOFS, FENCES, SOFT 
SHELTERS OR TREES IS LIKELY. SEVERE THUNDERSTORM WARNINGS ARE ISSUED 
WHEN IMMINENT OR OCCURRING THUNDERSTORMS ARE EXPECTED TO PRODUCE 
DAMAGING HAIL, WIND OR RAIN. 

EMERGENCY MANAGEMENT ONTARIO RECOMMENDS THAT YOU TAKE COVER 
IMMEDIATELY IF THREATENING WEATHER APPROACHES. 

PLEASE CONTINUE TO MONITOR ALERTS AND FORECASTS ISSUED BY 
ENVIRONMENT CANADA. 

TO REPORT SEVERE WEATHER IN ONTARIO, SEND AN EMAIL TO 
ONSTORM(AT)EC.GC.CA OR POST REPORTS ON X USING (HASH)ONSTORM. 

FOR MORE INFORMATION: 
HTTPS://WWW.ONTARIO.CA/PAGE/BE-PREPARED-EMERGENCY.

HTTP://WEATHER.GC.CA

END/OSPC