textproduct: Gray - Portland

SYNOPSIS

Cold, well below normal temperatures make a comeback today and tonight. An active weather pattern will feature a few more chances for light snow Tuesday night and again Wednesday. A break in the precipitation will occur late week although the weather will remain cold.

NEAR TERM /THROUGH TODAY/

Low pressure will move away from the forecast area today with any snow mostly ending before sunrise. It will be quite windy however, with occasional gusts 20 to 30 MPH into the first part of the morning. The winds then diminish through the afternoon as the center of high pressure nears. Wind chill values will be near zero at many locations in the forecast area early this morning. Highs are expected to top out a good 10 to 15 degrees below normal.

SHORT TERM /TONIGHT THROUGH TUESDAY/

High pressure centered overhead tonight along with snow cover will offer a very cold night tonight under mostly clear skies. Lows will be in the single numbers above zero on the coastal plain, central ME, and southern NH. However, mountain valleys will see readings dip well below zero.

Clouds will quickly increase on Tuesday as the next short wave trough approaches from the west. Highs will be in the 20s area- wide.

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/

Overview:

A persistent trough will remain over the Northeast through next weekend. Embedded short waves will keep the weather active with multiple light precipitation events Tuesday night, Wednesday, and another possible over the weekend. Temperatures will briefly climb warmer than normal Wednesday followed by colder the normal temperatures through the weekend.

Impacts:

*Light snow Tuesday night will amount to a coating to 2 inches and will bring slick travel on untreated surfaces.

*More widespread precipitation is expected late Wednesday morning through the evening. Slick travel is likely across the foothills and north where precipitation stays all snow with accumulations of 2 to 4 inches. South of the foothills warmer temperatures and a change to rain will limit impacts.

Details:

A weak wave skirts across New England Tuesday night bringing a period of light snow. Current guidance keeps amounts less than 2 inches, but could be enough to grease up the roads. Low temperatures Tuesday night will range from the single digits north to the teens south. There may be a several hour break in precipitation in time for the morning commute before a more organized area of low pressure tracks east out of the Great Lakes Wednesday afternoon.

Chances for precipitation increase late Wednesday morning with widespread precipitation likely Wednesday afternoon through the evening. Thermal profiles will be cold enough for snow across the area to start. Low pressure tracks near the Canadian Border Wednesday evening with southerly flow ahead of the system bring temperatures above freezing across southern NH and the coastal plain by mid day and into the upper 30s to low 40s during the afternoon. This will allow for a change to rain with rain likely into the evening commute. The rain/snow line looks to push into the foothills Wednesday afternoon with areas that stay all snow to the north forecast to receive 2 to 4 inches. The bulk of the precipitation ends before midnight with the attendant cold front crossing Thursday morning.

Thursday into Friday look mostly dry while cyclonic flow aloft maintains chances for snow showers in the mountains. Temperatures will trend below normal into the weekend with the next fast moving system bringing the next chance for light precipitation Saturday.

AVIATION /03Z MONDAY THROUGH FRIDAY/

Short Term...NW winds gust up to 25/30 kt prior to 13z this morning or so, slackening as afternoon goes on. VFR today through Tuesday daytime with much lighter winds.

Long Term...Periods of light snow Tuesday night will change to rain Wednesday south of the mountains with MVFR to IFR likely through Wednesday night. VFR likely prevails Thursday and Friday with the exception being KHIE where upslope clouds and -SHSN will persist.

MARINE

Short Term...Winds increase over the waters early this morning, with Gale conditions expected on the eastern waters as low pressure exits the Gulf of Maine. On Tuesday winds and seas are likely to be below SCA levels for most of the day, with winds shifting to southwesterlies and strengthening to SCA levels by the end of the day.

Long Term...A pair of disturbances cross New England Tuesday night and again Wednesday afternoon. These will keep SW flow elevated with SCAs likely needed Tuesday night through Wednesday night. Winds shift offshore Thursday with SCAs likely still needed for offshore flow through Friday.

GYX WATCHES/WARNINGS/ADVISORIES

ME...None. NH...None. MARINE...Gale Warning from 3 AM to 9 AM EST Monday for ANZ150-152. Small Craft Advisory from 4 AM to 11 PM EST Monday for ANZ151- 153. Small Craft Advisory from 1 AM Monday to 1 AM EST Tuesday for ANZ154.