There is an increased threat for tropical systems to impact Atlantic Canada during fall 2012.
"With the warmer water off Atlantic Canada, any tropical systems will have a greater chance of maintaining strength compared to normal as they move northward. Look for at least one named storm to threaten coastal Nova Scotia or Newfoundland," AccuWeather Expert Senior Meteorologist Brett Anderson said.
More storms are expected to recurve, passing the U.S. and heading toward Atlantic Canada, especially during the middle of fall, Anderson added.
Above-normal precipitation is forecast for Nova Scotia and Newfoundland for the season with tropical impacts factored in. Rough, battering surf and damaging winds may be other threats.
The unusually warm ocean water off the coast of Atlantic Canada will influence warmer temperatures and humid conditions for the region.
Temperatures should also run above normal across much of Ontario and southern Quebec, including the major cities of Montreal, Quebec City, Ottawa and Toronto.
Less rain than usual is predicted for the Ottawa, Toronto and Windsor areas, following a dry summer across parts of Ontario.
Anderson is forecasting a later-than-normal frost or freeze for eastern Canada.
However, with above-normal water temperatures of the Great Lakes, there is a greater potential for more intense lake-effect snow outbreaks if enough cold air arrives.
Farther north, dry, mild weather may mean a slow start to winter sports such as skiing and snowmobiling across northern and central portions of Ontario and Quebec.
A predominantly northwesterly flow will promote a fairly calm and quiet fall for the Canadian Prairies. Near-normal temperatures and precipitation are expected.
"Winnipeg, Manitoba, and Saskatoon and Regina, Saskatchewan, will have a pleasant fall," Anderson said. After very wet weather recently, the dry and mild fall may be welcomed by residents.
Dry weather should also dominate southwestern British Columbia with below-normal temperatures across western Canada.
"Large highs coming down from Yukon will bring quick shots of chilly air into British Columbia this fall," Anderson explained. Departures of 1-2 degrees C (2-4 degrees F) below normal are possible for the season. Interior British Columbia may have an early frost or freeze as well.
Vancouver will be drier and slightly cooler than normal.
The latter part of the fall should please avid skiers and winter sports enthusiasts that frequent resorts in the western mountains as the British Columbia snow base should get established on schedule.
A stretch of higher-than-average temperatures will continue across a large portion of the Western U.S. this week.
A dominant storm track featuring storms moving west to east across Europe will result in a stark contrast between cold air building across Scandinavia and milder air masses entrenched near the Mediterranean.
An El Nino-fueled October will feature more rainfall and storms for Southwest beginning this week.
After waves of cool air progress through the Midwest and Northeast this week, some areas will be cold enough for the first snow showers of the season by this weekend.
Tropical Storm Nora moved into to the Central Pacific Basin on Sunday, where unusually warm waters have already led to a record 13 tropical systems this hurricane season.
New England (1990)
Remains of Tropical Storms Klaus and Marco brought torrential rains and flooding. Parts of Connecticut had 6 inches of rain or more. Stafford, CT, had 4.20 inches.
East Coast (1846)
Great Hurricane of 1846. Track: Cuba, Key West, FL; GA; Carolinas; Chesapeake Bay; PA - major damage all areas (Similar to Hazel in 1954). Lashed the Delaware River "into a perfect fury and its roar would have drowned out the thunder of the Niagara.
Layton, NJ (1906)
11 degrees - record early season cold snap.