Cold windy day for Montreal - impressive rainfall totals

Several months worth of rain fell in just a few hours Wednesday morning on Islip, Long Island, NY, producing major flooding. (AP Photo)

For the third day in a row a major metro region in North America has been pounded by heavy rain and flash flooding. An entire summer's worth of rain fell on Long Island Wednesday morning just east of metro New York City. A new all time 24 hour New York state record was set at Islip, in Suffolk County after 13.27 inches (338mm) of rain fell in under 24 hours. In a two hour stretch alone during the morning commute, 9 inches fell. The rain overwhelmed the entire sewer system flooding major highways, homes and businesses. The tropical plume of moisture stretching north from the south Atlantic waters ran into a cool, fall like air mass over New England dumping the heavy rain in narrow bands across the region. By comparison New York City had only 0.5 inches of rainfall for the same period.

Meanwhile the same low pressure area brought heavy rain to eastern Ontario and southern Quebec. Over 60mm fell in Ottawa and Kemptville, with 35.2mm here on L'Ile Perrot and officially 44.4mm at Trudeau Airport. Quebec City had 62mm but it is still raining there, and south shore St. Hubert had 37mm. The upper level low responsible for all this wet weather remains over Quebec moving slowly north. Very cool air has settled over Quebec this morning with a current temperature of only 12C (54F) here on L'Ile Perrot. It will struggle to reach 17C (63F) today for a high under cloudy skies with a few breaks but also a few showers this afternoon. The same weather for Friday before temperatures moderate a little into the weekend, but still with the threat for showers. The weekend at this time looks unsettled as that stubborn low slowly weakens over northern Quebec.