The rivers themselves are usually 200 to 300 miles in width, and can extend over a thousand miles in length. They are notorious for producing heavy rain as they feed into larger storms and account for much of the global precipitation outside of the tropics.
They are like narrow conveyor belts of moisture laden air.
Heavy rains later this week in Central New York may be the result of an atmospheric river from the Caribbean northward all the way up the Appalachians into New York and New England.
Above: Computer forecast for Friday afternoon, May 16, 2014 showing heavy rain (blue and dark green colors) embedded in a moist flow from the Caribbean northward into New York State.
If the computer models are correct, this flow of moisture will prime the atmosphere over us for an approaching cold front from the west.
That front is the leading edge of cooler air approaching from the middle of the United States. It is due to arrive in the eastern Great Lakes on Friday.
As the cooler air from the west, collides with the moist atmospheric river from the Caribbean, the moisture-laden air is forced abruptly upwards into the atmosphere. This is a very efficient precipitation making process and can sometimes lead to heavy rain.
Some of our computer models are predicting more than 3 inches of rain on Friday and Friday night.
As we go through the week, we’ll talk a little more about this on line, and also on News Channel 9. In the meantime, you may want to keep an eye on satellite imagery. Watch for a possible stream of clouds developing northward from the Caribbean, perhaps as early as by Wednesday or Thursday.
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