WUCN12 CWTO 181103
YELLOW WARNING - SEVERE THUNDERSTORM
FOR NORTHERN ONTARIO
ISSUED BY ENVIRONMENT CANADA
AT 7:03 A.M. EDT MONDAY 18 MAY 2026.
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YELLOW LEVEL WARNING - SEVERE THUNDERSTORM - FOR:
=NEW= AGAWA - LAKE SUPERIOR PARK.

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IMPACT LEVEL: MODERATE
FORECAST CONFIDENCE: HIGH

==DISCUSSION==

UPDATED OR ENDED BY 9:02 A.M. EDT.

AT 7:03 A.M. EDT, ENVIRONMENT CANADA METEOROLOGISTS ARE TRACKING A 
SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WIND GUSTS, UP TO 
QUARTER SIZE HAIL AND HEAVY RAIN.

A LINE OF SEVERE THUNDERSTORMS WAS LOCATED FROM 14 KILOMETRES 
NORTHWEST OF GARGANTUA TO 30 KILOMETRES WEST OF MONTREAL RIVER 
HARBOUR, MOVING EAST AT 50 KM/H. 

HAZARDS: 
- TOONIE SIZE HAIL. 

LOCATIONS IMPACTED INCLUDE: 
LAKE SUPERIOR PROVINCIAL PARK, MONTREAL RIVER HARBOUR, BATCHAWANA 
RIVER PROVINCIAL PARK, GARGANTUA, AGAWA BAY, FRATER, ETON, MILLWOOD, 
MONTREAL FALLS.

DAMAGE TO ROOFS, FENCES, SOFT SHELTERS OR TREES IS LIKELY. LARGE 
HAIL MAY CAUSE SIGNIFICANT DAMAGE AND INJURY. TAKE IMMEDIATE COVER 
IF A THUNDERSTORM APPROACHES. IF OUTSIDE, PROTECT YOURSELF FROM 
FLYING DEBRIS AND HAIL. 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, 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