A fast-moving disturbance migrating across the the Great Lakes this morning---will produce scattered showers and thunderstorms along its path---from lower Michigan, Indiana and northwest Ohio to Pennsylvania,New York and the upper reaches of the Ohio Valley later today. The area of disturbed weather will eventually reach New England tonight. This disturbance will likely pass over---and briefly interact with the coastal low moving up the US portion of the Atlantic shoreline. This coastal low---currently producing a narrow band of moderate-to-heavy rainfalls and intermittent rain showers over the Outer Banks will press northeastward into the Gulf of Maine later tonight. It is already producing light rain and a few showers along the New Jersey coast, Long Island and interior portions of southern new England. Later today and through tonight---the entirety of the coastal low moves very near Cape Cod and precipitation will become more widespread for a time over New England. By Monday morning, most of the rainfall will be moving into Downeast Maine, Nova Scotia and New Brunswick---with much of the Northeast and Mid-Atlantic region---replaced with a cooler and drier Canadian airmass. An upper-level low centered over southern Nevada will be moving slowly northwestward today---and tonight, settle over the northern Great Basin. Increasing clouds and the threat of thunderstorms will gradually shift from the high deserts of Nevada and the Sierra Nevada---to the southern Cascades and high deserts of southeast Oregon and southern Idaho. With the flow pattern aloft---a light southerly to southeasterly wind---the southwest deserts, Rio Grande Valley, and Texas Panhandle---will experience a Subtropical-like airmass with mid-level moisture lifting upward along the south and southeast-facing slopes of the Southern Rockies. Expect isolated thunderstorms to move from the higher terrain into the adjacent lower valleys, with occasional moderate rainfall intensity across southern Texas, south-central New Mexico, southern Utah and east-central Arizona.
Posted on: Sun, 21 Sep 2014 13:54:43 +0000