WWCN11 CWTO 190017
YELLOW WATCH - SEVERE THUNDERSTORM
FOR SOUTHERN ONTARIO
UPDATED BY ENVIRONMENT CANADA
AT 8:17 P.M. EDT MONDAY 18 MAY 2026.
---------------------------------------------------------------------
YELLOW LEVEL WATCH - SEVERE THUNDERSTORM - FOR:
      INNISFIL - NEW TECUMSETH - ANGUS
      BARRIE - ORILLIA - MIDLAND
      PORT CARLING - PORT SEVERN
      BRACEBRIDGE - GRAVENHURST.

YELLOW LEVEL WATCH - SEVERE THUNDERSTORM - ENDED FOR:
      WINDSOR - ESSEX - CHATHAM-KENT
      SARNIA - LAMBTON
      RODNEY - SHEDDEN - WESTERN ELGIN COUNTY
      LONDON - MIDDLESEX
      HURON - PERTH
      MOUNT FOREST - ARTHUR - NORTHERN WELLINGTON COUNTY
      ORANGEVILLE - GRAND VALLEY - SOUTHERN DUFFERIN COUNTY
      SHELBURNE - MANSFIELD - NORTHERN DUFFERIN COUNTY
      SAUGEEN SHORES - KINCARDINE - SOUTHERN BRUCE COUNTY
      HANOVER - DUNDALK - SOUTHERN GREY COUNTY
      OWEN SOUND - BLUE MOUNTAINS - NORTHERN GREY COUNTY.

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

==DISCUSSION==

CONDITIONS ARE FAVOURABLE FOR THE DEVELOPMENT OF SEVERE 
THUNDERSTORMS THAT MAY BE CAPABLE OF PRODUCING STRONG WIND GUSTS AND 
LARGE HAIL.

HAZARDS: 
WIND GUSTS UP TO 100 KM/H 
HAIL UP TO TOONIE SIZE 

TIMING: 
THIS EVENING

LOCAL UTILITY OUTAGES ARE POSSIBLE. DAMAGE TO ROOFS, FENCES, 
BRANCHES OR SOFT SHELTERS IS POSSIBLE. WHEN THUNDER ROARS, GO 
INDOORS(EXCLAMATION MARK) LIGHTNING KILLS AND INJURES CANADIANS 
EVERY YEAR. SEVERE THUNDERSTORM WATCHES ARE ISSUED WHEN CONDITIONS 
ARE FAVOURABLE FOR THE DEVELOPMENT OF THUNDERSTORMS CAPABLE OF 
PRODUCING 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