textproduct: Gray - Portland

WHAT HAS CHANGED

No notable changes to the near and short term portion of forecast this early Friday morning. It's been a broken record featuring colder than normal air and this will continue through Saturday.

650am Update...Very light snow showers have been rotating through southern Maine much of the night, and will continue for another hour or so nearing the ME/NH border. Light snow will be most continuous NW of the mountains as downsloping dries the low levels to the SE.

KEY MESSAGES

1. Remaining very cold through Saturday albeit with dry weather.

2. A strong coastal low will likely remain far enough offshore Sunday into Monday for any significant local impacts but some light snow and gusty winds are still possible.

3. High astronomical tides Sunday through Monday combined with the offshore low pressure system may bring water levels to near minor flood stage during times of high tide.

DISCUSSION

KEY MESSAGE 1 DESCRIPTION...

Cold air advection continues today with temperatures below average. To make things worse, winds will be pretty stiff with gusts 20 to 25 MPH at times making it feel several degrees colder. Some lucky residents may be in a Mount Washington wind shadow a good portion of the day, noticing long periods of lighter winds. At this time that best potential looks to be along a line roughly from KIZG to KPWM and 10 to 20 or so miles either side. Mountain snow showers continue today.

Lighter winds for tonight, but that trade off is good radiational cooling with mostly clear skies. This will favor lower lows than the NBM at the better radiators.

Another fair weather day expected Saturday. Despite continued cold, winds will be lighter along with ample sunshine.

KEY MESSAGE 2 DESCRIPTION... Latest ensemble and AI based guidance is continuing to show a SE trend in the track of what will likely be a rather strong area of low pressure Sunday into Monday with most guidance keeping it well SE of Cape Cod. This will likely prevent any significant local impacts to the region. Despite this, there remains some potential for perhaps a little light snow or snow shower activity across southern areas.

Gusty N-NW winds are also possible as there will be a strong PGF between the low pressure system to our east and high pressure to the west. Wind gusts up to 30-35 mph are possible.

KEY MESSAGE 3 DESCRIPTION... High astronomical tides combined with storm surge of between 1-2 ft may bring total water levels up to near minor flood stage during times of high tide Sunday into Monday. Latest Stevens Institute ensemble probabilities show a less than 5% chance for anything greater than minor coastal flooding and therefore any impacts are currently anticipated to be minor.

AVIATION /12Z FRIDAY THROUGH TUESDAY/

Through 12z Saturday...Periods of light snow or snow showers will move south across northern NH and southern ME early this morning. This could result in brief cigs/vis lowering to MVFR. These conditions persist longer for points NW of the Whites and western ME mountains today. Trending VFR today with gusts up to 25kt at times. Offshore MVFR deck may backbuild towards coastal terminals, mainly PWM and PSM, this morning and again this evening. Think should mainly be FEW or SCT with > BKN limited. Lighter winds expected for tonight as pressure gradient slackens.

Outlook: SUNDAY / MONDAY...Mainly VFR conditions with gusty N-NW wind gusts between 25-30 kts possible. Low potential for some -SN across coastal TAF sites but forecast confidence is low.

TUESDAY...VFR conditions with W winds at 10-15 kts.

MARINE

W-WNW winds gusting to around 25 kt today will maintain SCA conditions over the outer waters. Freezing spray advisories continue all waters into early Saturday. Winds and seas come down below SCA levels tonight and Saturday as the pressure gradient relaxes.

Gale force N-NW winds possible Sunday through Sunday night as low pressure tracks SE of Cape Cod. Seas will build to 6-10 ft outside of the bays.

GYX WATCHES/WARNINGS/ADVISORIES

ME...Cold Weather Advisory until 10 AM EST this morning for MEZ007>009-012-018-019-023-024-033. NH...Cold Weather Advisory until 10 AM EST this morning for NHZ001>015. MARINE...Small Craft Advisory until 11 PM EST this evening for ANZ150- 152-154. Freezing Spray Advisory until 8 AM EST Saturday for ANZ150>154. Gale Watch from Sunday morning through Monday morning for ANZ150>154.