St. Lawrence Seaway Management Corporation

Seaway Opening and Closing Information

Opening of 2021 Seaway Navigation Season

• Radio Messages
• Seaway Notice No. 1
• Notices to Shipping – Montreal/Lake Ontario
• Notices to Shipping – Welland Canal

Weather Information:

• Weather Forecasts
  • The Weather Network: 14 Day Trend – Dorval
  • The Weather Network: 14 Day Trend – St. Catharines
  • Environment Canada: 30 day Temperature Forecast
  • NOAA: Monthly Temperature Forecast
• Water Levels and Environmental Data (MLO/Welland)
• Marine Forecasts and Warnings for Canada

Ice Information:

• Canadian Ice Service – Latest Ice Conditions
• Canadian Coast Guard – Ice Charts
• Canadian Coast Guard – Ice navigation in Canadian Waters
• Outlook for break-up of Ice (Issued Feb 2nd, 2021)