Wednesday, September 28, 2016

September warmth to continue into October

A slow-moving upper-level low pressure area will persist across our region through the weekend. Montreal will remain on the edge of the system with frequent clouds and showers, but also some breaks.

According to the National Oceanic and Atmospheric Administration (NOAA), August was the 16th consecutive month with temperatures above average globally. This has not occurred over the last 137 years; basically, it has been exceptionally warm. August was 1.66F above the 20th Century average, eclipsing the record set just last year. The average temperature for 2016 to date is 1.82F above the long-term average. In Montreal, we experienced the second-warmest June-to-August period on record. The warmth continued into September. So far, the monthly average is 17.8C, above the normal of 15.5C. It has been extremely dry once again, with only 31.2mm of rain this month, compared to the normal of 83.1mm.

For the short term through the start of October, we are expecting temperatures to remain slightly above average. Stubborn low pressure will very slowly move from the central Great Lakes southeast towards southern New York. The system will then lift north again into eastern Ontario. Southern Quebec should remain on the periphery of the moisture, with showers forecast Saturday and Sunday, but not a washout. Gusty northeast winds will prevail through the end of the week as well, making it feel a little cooler than the advertised highs. Several mornings this week have featured a marine layer of clouds and fog generated by the northeast winds channeling down the St. Lawrence Valley.

Tropical Storm Matthew
Tropical storm Matthew has formed in the Atlantic Basin, 40km southwest of St. Lucia. Matthew is moving west at 20mph (31km/h), with 60mph (100km/h) winds. This storm is forecast to strengthen and become a hurricane by Friday. Forecasters then expect Matthew to turn to the north and impact Jamaica. Beyond then, there is the potential the storm could affect the Gulf Coast or even the eastern seaboard.

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