The warmth came as a result of strong high pressure moving into the Atlantic and low pressure forming in the Mississippi Valley. The result has been a strong push of warm and increasingly humid air from the southern US. The flow will strengthen today with a forecast high of 24C in Montreal. If it occurs it will break the previous record high for the date, 22.8C (73F), established in 1971. It should be a dry day with partial sunshine this afternoon. The aforementioned low pressure area will lift north across the Great Lakes and eventually sweep a cold front into the St. Lawrence Valley by Thursday. Until then it will remain very warm for mid-October with highs in the 20's and lows in the teens. By Thursday expect a period of moderate rain with perhaps 25-50mm (1-2 inches) area wide into Friday morning. Temperatures will begin lowering through the teens to around 10C (50F) for a high by Sunday as we settle back into reality.
|The path of Hurricane Gonzala as forecast by the National Hurricane Center.|
The weather system bringing us this late season warmth is also responsible for a late season severe weather outbreak. Thunderstorms across the southern US on Monday produced nearly a dozen tornadoes and killed two in Arkansas. The storms stretched from Texas into Alabama and will spread eat today from Virginia to Florida. There may even be some thunder in northern New York and southern Quebec by Thursday, but no severe weather is forecast.
The tropics have also become active as we have a strong Hurricane Gonzala north of Puerto Rico this morning. Gonzala is a strengthening storm with winds of 110mph and is expected to become a major hurricane today while moving away from the islands at 13mph. The eye of Gonzala is about 90 miles (145km) north northeast of St Thomas with a lowering central pressure at 974mb and deepening. The storm lashed the Virgin Islands on Monday with heavy rain and strong winds as well as Puerto Rico. Winds gusted to 88mph on the island of Antigua with downed trees and roofs off many homes. The next target for the hurricane will be Bermuda followed by a gradual weakening as it approaches Atlantic Canada by next weekend.