textproduct: Gray - Portland

WHAT HAS CHANGED

Very little change to the going forecast this Wednesday evening.

KEY MESSAGES

1. High pressure remains in control of the weather pattern across northern New England through the weekend while an ocean storm passes offshore. Northerly gusts of 30 to 35 MPH possible later Thursday into Friday.

DISCUSSION

KEY MESSAGE 1 DESCRIPTION...

It will continue to be a pleasant late afternoon and evening across the region with temperatures quickly cooling after sunset. Cirrus will gradually increase from south to north tonight from a nor'easter passing to the SE of Cape Cod. Given that cirrus typically does not have a big impact on radiational cooling and that dew points are low, went ahead and lowered NBM forecast lows by a few degrees. This cools some interior valleys into the 20s/lower 30s with middle to upper 30s elsewhere. The warmest readings will be along the coast as mixing will likely linger longer into the night.

High pressure will remain over southern Quebec on Thursday into Thursday night as a dry cold front crosses from the north and low pressure passes well offshore. Partly to mostly sunny skies will prevail with highs into the lower 60s south of the mtns with 50s across the north. The increasing pressure gradient force from the offshore low and high centered to our NW will allow for increasing winds throughout the day with N gusts up to 30-35 mph likely from Thursday afternoon through the first half of Friday.

Upper low/nor'easter will continue to move northeast, well out to sea. With persistent northerly flow aloft, expect a chilly and blustery day on Friday with highs mainly in the mid 40s to mid 50s. The gusty winds will make it feel even colder.

As winds diminish Friday night, a mostly clear sky should prove optimal for radiational cooling and very cold temperatures. The latest NBM is advertising lows in the 20s across the entire forecast area and this may end up being on the warm side depending on the presence of high clouds.

High pressure then dominates the weather pattern through the weekend as an upper level ridge nudges into the region. This will lead to a gradual warmup through the weekend and into next week. Highs on Saturday should mainly be back in the 50s with some 60s returning Sunday and Monday. A cold front will sweep through on Monday which will lead to cooler temperatures into midweek. As of now, this cold front looks to be dry but we could end up seeing some low precipitation chances as we move closer in time.

AVIATION /00Z THURSDAY THROUGH MONDAY/

Through Thursday: Patchy fog is possible in the river valleys tonight into Thursday morning. Otherwise, VFR conditions prevail with N winds of 10-15 kts. Gusts will increase late Thursday through the first half of Friday with gusts up to 30 kts.

Outlook...

Thursday: Mostly VFR. Northwest winds may gust 20-30 kt.

Thursday night-Monday...VFR prevails. Northerly gusts up to 30 kt Thursday night into Friday morning.

MARINE

High pressure remains in control of the weather pattern across New England, while an ocean storm tracks outside the Gulf of Maine and through the Grand Banks through Friday. SCA winds in northeasterly flow last through at least Friday, while waves likely persist into the weekend. Northerly gales are expected outside of the bays later Thursday into Friday as the low deepens east of the waters. Seas then gradually subside through the weekend as high pressure remains in control.

GYX WATCHES/WARNINGS/ADVISORIES

ME...None. NH...None. MARINE...Small Craft Advisory until 8 PM EDT Thursday for ANZ150-152- 154. Gale Warning from 8 PM Thursday to 2 PM EDT Friday for ANZ150- 152-154-180-182-184. Small Craft Advisory from 8 PM Thursday to 2 PM EDT Friday for ANZ151-153.