Subj : Southern Ontario Weather To : All From : Northern Realms Date : Thu Aug 14 2025 15:35:00 FPCN11 CWTO 141930 Forecasts for Southern Ontario and the National Capital Region issued by Environment Canada at 3:30 p.m. EDT Thursday 14 August 2025 for tonight Friday and Friday night. The next scheduled forecast will be issued at 5:00 a.m. EDT Friday. City of Toronto. Tonight..Partly cloudy. Becoming clear after midnight. Low 20. Friday..Sunny. High 29. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 21. Windsor - Leamington - Essex County. Tonight..A few clouds. Fog patches developing after midnight. Low 16. Friday..Sunny. Fog patches dissipating in the morning. High 30. Humidex 37. UV index 9 or very high. Friday night..Clear. Low 18. Chatham-Kent - Rondeau Park. Tonight..Partly cloudy. Becoming clear this evening. Fog patches developing after midnight. Low 16. Friday..Sunny. Fog patches dissipating in the morning. High 29. Humidex 36. UV index 9 or very high. Friday night..Clear. Low 18. Sarnia - Petrolia - Western Lambton County. Tonight..Partly cloudy. Fog patches developing after midnight. Low 16. Friday..A mix of sun and cloud. Clearing late in the afternoon. Fog patches dissipating in the morning. High 29. Humidex 33. UV index 9 or very high. Friday night..Clear. Low 18. Watford - Pinery Park - Eastern Lambton County. Tonight..A few clouds. Fog patches developing after midnight. Low 16. Friday..Sunny. Fog patches dissipating in the morning. High 30. Humidex 35. UV index 9 or very high. Friday night..Clear. Low 17. Rodney - Shedden - Western Elgin County. Tonight..Partly cloudy. Becoming clear this evening. Fog patches developing after midnight. Low 16. Friday..Sunny. Fog patches dissipating in the morning. High 29. Humidex 34. UV index 9 or very high. Friday night..Clear. Low 18. St. Thomas - Aylmer - Eastern Elgin County. Tonight..Partly cloudy. Becoming clear this evening. Fog patches developing after midnight. Low 16. Friday..Sunny. Fog patches dissipating in the morning. High 28. Humidex 34. UV index 9 or very high. Friday night..Clear. Low 16. Strathroy - Komoka - Western Middlesex County. Tonight..Clearing. Fog patches developing after midnight. Low 16. Friday..Mainly sunny. Fog patches dissipating in the morning. High 30. Humidex 35. UV index 9 or very high. Friday night..Clear. Low 18. London - Parkhill - Eastern Middlesex County. Tonight..Partly cloudy. Becoming clear this evening. Fog patches developing after midnight. Low 16. Friday..Mainly sunny. Fog patches dissipating in the morning. High 30. Humidex 35. UV index 9 or very high. Friday night..Clear. Low 16. Simcoe - Delhi - Norfolk. Tonight..Partly cloudy. Becoming clear this evening. Fog patches developing after midnight. Low 15. Friday..Sunny. Fog patches dissipating in the morning. High 29. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 15. Dunnville - Caledonia - Haldimand. Tonight..Clearing early this evening. Fog patches developing after midnight. Low 15. Friday..Sunny. Fog patches dissipating in the morning. High 30. Humidex 35. UV index 8 or very high. Friday night..Clear. Low 14. Woodstock - Tillsonburg - Oxford County. Tonight..Partly cloudy. Becoming clear this evening. Fog patches developing after midnight. Low 15. Friday..Sunny. Fog patches dissipating in the morning. High 30. Humidex 35. UV index 8 or very high. Friday night..Clear. Low 15. Brantford - County of Brant. Tonight..Partly cloudy. Becoming clear this evening. Fog patches developing after midnight. Low 15. Friday..Sunny. Fog patches dissipating in the morning. High 30. Humidex 35. UV index 8 or very high. Friday night..Clear. Low 15. Niagara Falls - Welland - Southern Niagara Region. Tonight..Partly cloudy. Becoming clear this evening. Fog patches developing after midnight. Low 19. Friday..Sunny. Fog patches dissipating in the morning. High 30. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 20. St. Catharines - Grimsby - Northern Niagara Region. Tonight..A few clouds. Fog patches developing after midnight. Wind northeast 20 km/h becoming light early this evening. Low 18. Friday..Sunny. Fog patches dissipating in the morning. High 29. Humidex 36. UV index 8 or very high. Friday night..Clear. Low 19. City of Hamilton. Tonight..Clear. Fog patches developing after midnight. Wind northeast 20 km/h becoming light early this evening. Low 17. Friday..Sunny. Fog patches dissipating in the morning. High 29. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 18. Burlington - Oakville. Tonight..Partly cloudy. Becoming clear near midnight. Low 18. Friday..Sunny. High 29. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 19. Halton Hills - Milton. Tonight..Partly cloudy. Low 17. Friday..Sunny. High 29. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 19. Mississauga - Brampton. Tonight..Partly cloudy. Low 18. Friday..Sunny. High 30. Humidex 35. UV index 8 or very high. Friday night..Clear. Low 19. Caledon. Tonight..Partly cloudy. Clearing before morning. Fog patches developing overnight. Low 16. Friday..Mainly sunny. Fog patches dissipating in the morning. High 29. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 18. Vaughan - Richmond Hill - Markham. Tonight..Partly cloudy. Low 18. Friday..Sunny. High 30. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 19. Newmarket - Georgina - Northern York Region. Tonight..Partly cloudy. Low 17. Friday..Mainly sunny. High 29. Humidex 33. UV index 8 or very high. Friday night..Clear. Low 17. Pickering - Oshawa - Southern Durham Region. Tonight..Partly cloudy. Low 17. Friday..Sunny. High 29. Humidex 33. UV index 8 or very high. Friday night..Clear. Low 17. Uxbridge - Beaverton - Northern Durham Region. Tonight..Partly cloudy. Low 17. Friday..Sunny. High 29. Humidex 33. UV index 8 or very high. Friday night..Clear. Low 17. Goderich - Bluewater - Southern Huron County. Tonight..Partly cloudy. Fog patches developing overnight. Low 16. Friday..A mix of sun and cloud. Fog patches dissipating in the morning. High 29. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 17. Wingham - Blyth - Northern Huron County. Tonight..Partly cloudy. Fog patches developing overnight. Low 16. Friday..A mix of sun and cloud. Fog patches dissipating in the morning. High 29. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 16. Stratford - Mitchell - Southern Perth County. Tonight..Partly cloudy. Fog patches developing overnight. Low 16. Friday..A mix of sun and cloud. Fog patches dissipating in the morning. High 30. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 17. Listowel - Milverton - Northern Perth County. Tonight..Partly cloudy. Fog patches developing overnight. Low 15. Friday..A mix of sun and cloud. Fog patches dissipating in the morning. High 30. Humidex 34. UV index 8 or very high. Friday night..Clearing late in the evening. Low 17. Kitchener - Cambridge - Region of Waterloo. Tonight..Partly cloudy. Clearing late this evening. Fog patches developing overnight. Low 15. Friday..Sunny. Fog patches dissipating in the morning. High 29. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 17. Guelph - Erin - Southern Wellington County. Tonight..Partly cloudy. Clearing after midnight. Fog patches developing overnight. Low 15. Friday..Sunny. Fog patches dissipating in the morning. High 29. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 17. Mount Forest - Arthur - Northern Wellington County. Tonight..Partly cloudy. Clearing late this evening. Fog patches developing overnight. Low 16. Friday..Sunny. Becoming a mix of sun and cloud near noon. Fog patches dissipating in the morning. High 29. Humidex 33. UV index 8 or very high. Friday night..Clearing. Low 17. Orangeville - Grand Valley - Southern Dufferin County. Tonight..Partly cloudy. Fog patches developing overnight. Low 15. Friday..Mainly sunny. Fog patches dissipating in the morning. High 29. Humidex 34. UV index 8 or very high. Friday night..Clearing. Low 17. Shelburne - Mansfield - Northern Dufferin County. Tonight..Partly cloudy. Clearing after midnight. Low 15. Friday..A mix of sun and cloud. High 29. Humidex 34. UV index 8 or very high. Friday night..Clearing. Low 17. Innisfil - New Tecumseth - Angus. Tonight..Partly cloudy. Clearing before morning. Low 15. Friday..Mainly sunny. Increasing cloudiness near noon. High 30. Humidex 35. UV index 8 or very high. Friday night..Clearing. Low 17. Saugeen Shores - Kincardine - Southern Bruce County. Tonight..Partly cloudy. Becoming clear this evening. Fog patches developing overnight. Low 17. Friday..Mainly sunny. Fog patches dissipating in the morning. High 27. Humidex 32. UV index 8 or very high. Friday night..Clear. Low 20. Bruce Peninsula - Sauble Beach - Tobermory. Tonight..A few clouds. Wind northeast 20 km/h gusting to 40 becoming light early this evening. Low 16. Friday..Mainly sunny. High 26. Humidex 31. UV index 8 or very high. Friday night..Clear. Wind becoming southwest 20 km/h overnight. Low 20 with temperature rising to 21 by morning. Hanover - Dundalk - Southern Grey County. Tonight..Partly cloudy. Clearing near midnight. Low 16. Friday..Sunny. Becoming a mix of sun and cloud near noon. High 29. Humidex 34. UV index 8 or very high. Friday night..Clearing. Low 17. Owen Sound - Blue Mountains - Northern Grey County. Tonight..Partly cloudy. Becoming clear this evening. Low 16. Friday..Sunny. High 28. Humidex 33. UV index 8 or very high. Friday night..Clear. Low 17. Barrie - Collingwood - Hillsdale. Tonight..Partly cloudy. Low 17. Friday..A mix of sun and cloud. High 30. Humidex 37. UV index 8 or very high. Friday night..Clearing in the evening. Low 17. Midland - Coldwater - Orr Lake. Tonight..Partly cloudy. Low 17. Friday..Mainly sunny. High 29. Humidex 36. UV index 8 or very high. Friday night..A few clouds. Low 17. Orillia - Lagoon City - Washago. Tonight..Partly cloudy. Low 17. Friday..Sunny. Becoming a mix of sun and cloud in the afternoon. High 29. Humidex 36. UV index 8 or very high. Friday night..Clearing in the evening. Low 17. Cobourg - Colborne - Western Northumberland County. Tonight..Partly cloudy. Clearing after midnight. Low 18. Friday..Sunny. High 28. Humidex 33. UV index 8 or very high. Friday night..Clear. Low 16. Belleville - Quinte West - Eastern Northumberland County. Tonight..Partly cloudy. Clearing after midnight. Low 15. Friday..Sunny. High 29. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 16. Picton - Sandbanks Park. Tonight..Partly cloudy. Becoming clear after midnight. Low 16. Friday..Sunny. High 27. Humidex 32. UV index 8 or very high. Friday night..Clear. Low 18. Napanee - Consecon. Tonight..Partly cloudy. Clearing after midnight. Low 14. Friday..Sunny. High 30. Humidex 35. UV index 8 or very high. Friday night..Clear. Low 16. Kingston - Odessa - Frontenac Islands. Tonight..Partly cloudy. Becoming clear late this evening. Wind north 20 km/h gusting to 40 becoming light early this evening. Low 14. Friday..Sunny. High 30. Humidex 35. UV index 8 or very high. Friday night..Clear. Low 15. Lindsay - Southern Kawartha Lakes. Tonight..Partly cloudy. Low 16. Friday..Mainly sunny. High 29. Humidex 33. UV index 8 or very high. Friday night..Clear. Low 16. Fenelon Falls - Balsam Lake Park - Northern Kawartha Lakes. Tonight..Partly cloudy. Low 14. Friday..Mainly sunny. High 29. Humidex 33. UV index 8 or very high. Friday night..Clearing in the evening. Low 16. Peterborough City - Lakefield - Southern Peterborough County. Tonight..Partly cloudy. Low 14. Friday..Mainly sunny. High 30. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 13. Apsley - Woodview - Northern Peterborough County. Tonight..Partly cloudy. Low 14. Friday..A mix of sun and cloud. High 29. Humidex 33. UV index 7 or high. Friday night..Clear. Low 13. Stirling - Tweed - Madoc. Tonight..Partly cloudy. Low 16. Friday..Mainly sunny. High 30. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 16. Tamworth - Sydenham - South Frontenac. Tonight..Partly cloudy. Clearing this evening. Low 16. Friday..Sunny. High 30. Humidex 34. UV index 8 or very high. Friday night..Clear. Low 15. Kaladar - Bannockburn - Bon Echo Park. Tonight..Partly cloudy. Clearing late this evening. Low 10. Friday..Mainly sunny. High 29. Humidex 33. UV index 8 or very high. Friday night..Clear. Low 12. Bancroft - Hastings Highlands - Denbigh. Tonight..Partly cloudy. Low 9. Friday..A mix of sun and cloud. High 28. Humidex 32. UV index 7 or high. Friday night..Partly cloudy. Becoming clear in the evening. Low 12. Gananoque - Mallorytown. Tonight..Partly cloudy. Becoming clear this evening. Low 13. Friday..Sunny. High 30. Humidex 33. UV index 8 or very high. Friday night..Clear. Low 15. Brockville - Prescott. Tonight..Partly cloudy. Becoming clear this evening. Low 12. Friday..Sunny. High 29. Humidex 32. UV index 8 or very high. Friday night..Clear. Low 15. Westport - Charleston Lake. Tonight..Partly cloudy. Becoming clear this evening. Low 13. Friday..Sunny. High 30. Humidex 33. UV index 8 or very high. Friday night..Clear. Low 15. Merrickville-Wolford - Kemptville. Tonight..Partly cloudy. Becoming clear this evening. Low 11. Friday..Sunny. High 28. Humidex 31. UV index 8 or very high. Friday night..Clear. Low 12. Ottawa North - Kanata - Orl‚ans. Tonight..Partly cloudy. Becoming clear this evening. Wind north 20 km/h gusting to 40 becoming light early this evening. Low 13. Friday..Sunny. High 28. Humidex 31. UV index 8 or very high. Friday night..Clear. Low 14. Ottawa South - Richmond - Metcalfe. Tonight..Partly cloudy. Becoming clear this evening. Low 12. Friday..Sunny. High 28. Humidex 31. UV index 8 or very high. Friday night..Clear. Low 14. Gatineau. Tonight..Partly cloudy. Becoming clear this evening. Low 12. Friday..Sunny. High 28. Humidex 31. UV index 8 or very high. Friday night..Clear. Low 13. Prescott and Russell. Tonight..Partly cloudy. Becoming clear this evening. Low 11. Friday..Sunny. High 27. Humidex 29. UV index 8 or very high. Friday night..Clear. Low 13. Morrisburg - Long Sault. Tonight..Partly cloudy. Becoming clear this evening. Low 11. Friday..Sunny. High 27. Humidex 29. UV index 8 or very high. Friday night..Clear. Low 13. Cornwall - Lancaster. Tonight..Partly cloudy. Clearing this evening. Low 11. Friday..Sunny. High 27. Humidex 29. UV index 8 or very high. Friday night..Clear. Low 13. Winchester - Newington. Tonight..Partly cloudy. Becoming clear this evening. Low 11. Friday..Sunny. High 27. Humidex 29. UV index 8 or very high. Friday night..Clear. Low 13. Maxville - Alexandria. Tonight..Partly cloudy. Clearing this evening. Low 11. Friday..Sunny. High 26. Humidex 29. UV index 8 or very high. Friday night..Clear. Low 12. Plevna - Sharbot Lake - Western Lanark County. Tonight..Partly cloudy. Clearing this evening. Low 11. Friday..Sunny. Becoming a mix of sun and cloud in the morning. High 29. Humidex 32. UV index 8 or very high. Friday night..Clear. Low 15. Smiths Falls - Perth - Eastern Lanark County. Tonight..Partly cloudy. Becoming clear this evening. Low 12. Friday..Sunny. High 29. Humidex 32. UV index 8 or very high. Friday night..Clear. Low 14. Port Carling - Port Severn. Tonight..Partly cloudy. Low 21. Friday..A mix of sun and cloud. Wind becoming southwest 20 km/h near noon. High 29. Humidex 35. UV index 8 or very high. Friday night..Clear. Wind southwest 20 km/h becoming light in the evening. Low 20. Bracebridge - Gravenhurst. Tonight..Partly cloudy. Low 15. Friday..A mix of sun and cloud. Wind becoming southwest 20 km/h near noon. High 30. Humidex 35. UV index 8 or very high. Friday night..Clear. Wind southwest 20 km/h becoming light in the evening. Low 15. Town of Parry Sound - Rosseau - Killbear Park. Tonight..Partly cloudy. Low 13. Friday..Sunny. Wind becoming southwest 20 km/h near noon. High 28. Humidex 33. UV index 8 or very high. Friday night..Clear. Becoming partly cloudy overnight. Wind southwest 20 km/h becoming light in the evening. Low 15. Huntsville - Baysville. Tonight..Partly cloudy. Low 13. Friday..Mainly sunny. Wind becoming southwest 20 km/h near noon. High 30. Humidex 35. UV index 8 or very high. Friday night..Clear. Wind southwest 20 km/h becoming light in the evening. Low 15. Haliburton - Minden - Southern Haliburton County. Tonight..Partly cloudy. Low 14. Friday..A mix of sun and cloud. Wind becoming southwest 20 km/h near noon. High 28. Humidex 33. UV index 8 or very high. Friday night..Clearing in the evening. Wind southwest 20 km/h becoming light in the evening. Low 16. Oxtongue Lake - Fort Irwin - Northern Haliburton County. Tonight..Partly cloudy. Low 10. Friday..A mix of sun and cloud. Wind becoming southwest 20 km/h near noon. High 28. Humidex 33. UV index 8 or very high. Friday night..Clearing in the evening. Wind southwest 20 km/h becoming light in the evening. Low 13. Barry's Bay - Killaloe. Tonight..Clear. Becoming partly cloudy after midnight. Low 9. Friday..Mainly cloudy. High 29. Humidex 32. UV index 7 or high. Friday night..Clearing in the evening. Low 13. Renfrew - Arnprior - Calabogie. Tonight..A few clouds. Low 10. Friday..A mix of sun and cloud. High 28. Humidex 31. UV index 8 or very high. Friday night..Clearing late in the evening. Low 15. Petawawa - Pembroke - Cobden. Tonight..A few clouds. Low 10. Friday..Mainly cloudy. High 28. Humidex 31. UV index 7 or high. Friday night..Clearing in the evening. Low 15. Western Algonquin Park - Lake of Two Rivers. Tonight..Clear. Becoming partly cloudy near midnight. Low 8. Friday..A mix of sun and cloud. Wind becoming southwest 20 km/h near noon. High 28. Humidex 32. UV index 8 or very high. Friday night..Clear. Wind southwest 20 km/h becoming light in the evening. Low 13. Deep River - Whitney - Eastern Algonquin Park. Tonight..Clear. Becoming partly cloudy near midnight. Low 8. Friday..A mix of sun and cloud. Wind becoming southwest 20 km/h near noon. High 28. Humidex 32. UV index 8 or very high. Friday night..Clear. Wind southwest 20 km/h becoming light in the evening. Low 13. Bayfield Inlet - Dunchurch. Tonight..Partly cloudy. Low 12. Friday..Sunny. Wind becoming southwest 20 km/h near noon. High 27. Humidex 32. UV index 8 or very high. Friday night..Clear. Becoming partly cloudy overnight. Wind southwest 20 km/h becoming light in the evening. Low 16. South River - Burk's Falls. Tonight..Partly cloudy. Low 11. Friday..Sunny. Wind becoming southwest 20 km/h near noon. High 28. Humidex 33. UV index 8 or very high. Friday night..Clear. Becoming partly cloudy overnight. Wind southwest 20 km/h becoming light in the evening. Low 16. End $$$$^^ --- up 3 days, 8 hours, 16 minutes * Origin: Northern Realms (1:229/664) .