The combination of tropical moisture and a vigorous storm from the Midwest could unleash enough rain on New England, eastern upstate New York and southern Quebec Friday and Friday night to cause a new round of flooding.
The "Hybrid Howler" that slammed Florida last weekend has recently soaked the ground over the northeastern U.S. and southeastern Canada.
While through Friday it appears that not enough rain will fall to cause substantial flooding issues in much of the mid-Atlantic, serious flooding problems are possible in much of New England, southern Quebec, eastern upstate New York and on part of Long Island.
High water could threaten homes and businesses in some communities, as well as those who choose to foolishly cross flooded roadways.
A general 1 to 3 inches (25 to 75 millimeters) of rain are forecast to fall on this area Friday into Friday night, which in most cases would not be a serious problem. However, locally higher amounts are possible, and the bulk of this rain could fall during a 6- to 12-hour period.
A rather high percentage of the area received 150 to 200 percent of their normal rainfall from Aug. 15 into Oct. 13. In many areas from Connecticut, Rhode Island and central and northern Massachusetts to southern Quebec, this represents around a foot or more of rain (300 millimeters).
The risks will range from flash, urban, poor-drainage-area and small-stream flooding to significant rises on area rivers.
Locations in the Northeast and Canada bordering the threat area also run the risk of brief urban and poor-drainage-area flooding due to the intensity of the downpours for a time. This includes New York City, Rochester and Binghamton in N.Y., Philadelphia, Scranton and Wilkes-Barre, Pa., Atlantic City, Paterson and Trenton , N.J., Fredericton, Moncton and St. John, N.B. and Halifax, N.S.
This image from the National Weather Service shows the approximate amount of rain needed to fall during a six-hour period to cause flash flooding.
The combination of fallen leaves and wet roads will make for slick travel throughout the area. Be especially careful on secondary roads.
The combination of fallen leaves and even modest downpours can lead to blocked storm drains and street flooding.
Travel delays are to be expected, along with poor conditions for outdoor activities.
As Meteorologist Brian Edwards pointed out in a recent story on AccuWeather.com, cold, gusty winds will follow the rain in the region over the weekend.
Next week, there is also potential for a new round of flooding in parts of the region, along with accumulating snow at some not-so-high elevations of the central Appalachians and around the Great Lakes.
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An unusually strong push of cool air for early September will move southward along the Atlantic Seaboard into the Labor Day weekend, before July-like heat returns by next week.
While lulls in tropical activity in the Atlantic will continue, a rapid end to the hurricane season in September does not always occur during an El Nino.
After heat has dominated headlines this summer, cool air has finally taken control of the northern half of Europe with no signs of departing anytime soon.
While Tropical Storm Kevin will stay well away from Mexico, its moisture will still lead to an increase in showers and thunderstorms from Baja California to the Four Corners region of the United States.
A stormy weather pattern will prevail through September across much of southern South America.
Denver, CO (1961)
Earliest snow on record; a total of 4.2 inches. A great storm raged at high elevations with 2-3 feet of snow closing roads on Labor Day weekend.
Coffeyville, KS (1970)
Hailstone 17.5/44 cm in circumference 1.671 lb/757 gm.
Long Island NY (1821)
Long Island hurricane of 1821 struck western Long Island. The storm affected a densely populated area where weather observers were common.