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Timing the Showers Arrival and Impact Sunday

By Meteorologist Joe Joyce, WBZ-TV

 The variety of model solutions have my head in a tailspin on the arrival time of these showers Sunday. As high pressure pulls off the coast today, Moisture from the Carolinas will track up through the mid-Atlantic states and into New England Early tomorrow morning. The concern is the timing of the eastward progression of the rain. Let’s put the variety of options on the table and see if we can find the answer.

12 NAM Has rain tracking from CT into Western MA during the morning and lifting north. Eastern New England remains dry, and warm, but SE winds keep it a bit cooler at coast. High pressure off the coast strong enough to keep sunday dry for most

06Z GFS has a wet early morning in CT which weakens and does not advance eastward. High pressure hold and keeps Eastern MA dry through the afternoon

WRF is dry all day Sunday and has pretty much all the rain missing us entirely.

WSi RPM has rain pushing into CT during the late morning and afternoon, keeps Eastern MA dry through the day with the arrival of rain showers in the 6-8 PM time period

The ever consistant 00 Z Euro has rain in western New England during the morning and tracking into VT and NH during the afternoon keeping Eastern MA dry through the daylight hours

SUNY MM5 has rain at the  south coast of CT, with rain advancing northward during the afternoon. Not a nice looking mid-late afternoon for most in southern New England

SREF has a wetter appearance for Sunday with rain in the west during the morning and spreading east during the afternoon

So there are a variety of solutions with the majority having high pressure  holding on long and strong enough to keep the rain away for most of the daylight hours for Eastern MA.

Clouds will continue to gradually increase and thicken through the weekend. While the coast should remain dry tomorrow, the risk inland for  showers increases, especially once you get west of Worcester. The clouds and cool SE winds will keep temps in the 70’s near 80. The warm spot will be NH and ME in the Lwr 80’s. Only in the upper 60’s and Lwr 70’s where it will be raining out west.

The rain in full begins Sunday night. The heaviest rain should move through late Sunday night and Monday morning with a wave of low pressure tracking very close to the south coast. Energy coming in from the Great Lakes, Midwest will link up with a moist feed up the Atlantic sea board to create a period of heavier downpours during this time. Rain will taper to showers Monday Afternoon. We will have to watch a secondary low forming along the front which could keep clouds locked in Tuesday along with much lighter scattered showers lingering. If this all comes together, these downpours may deliver an additional 1-3″ of rainfall from Sunday Night-Tues AM which could cause more urban flooding in brief downpours.

Monday and Tuesday will feature below normal temps  near 70-75. High pressure builds in for the midweek with sunshine and warming temps back to near 80.


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