textproduct: Gray - Portland

WHAT HAS CHANGED

Little has changed from the ongoing forecast. A warmer and drier next couple of days are still expected, followed by a cooler and more showery 2nd half of the week.

KEY MESSAGES

1. Rain tapers off this afternoon, with dry and warmer weather expected through Wednesday.

2. A cooler and more unsettled pattern develops the second half of this week and likely continues through the weekend.

DISCUSSION

KEY MESSAGE 1 DESCRIPTION...

Radar and satellite imagery currently show rain moving out of the region from east to west, with most precipitation over eastern Maine at this point. Skies will clear through the remainder of the day and conditions look to dry out fairly quickly.

Persistent mid-level ridging and clearer skies on Tuesday and Wednesday will allow for notably warmer temperatures. High pressure should make for a tranquil and sunny Tuesday with high temperatures in the lower 80s. Low pressure moves across Quebec Tuesday night and will bring a cold front southward during the day Wednesday. Wednesday will be another warm day with temperatures in the mid-80s. The cold front looks to move mostly across northern New England during the morning, which will limit thunderstorm chances. A slower passage of the front could allow for a couple of discrete thunderstorms to develop across southern NH. The environment ahead of the front is not very impressive, with developing storms likely to stay sub-severe.

KEY MESSAGE 2 DESCRIPTION...

After a couple of warm days, longwave troughing develops over the eastern CONUS, cooling temperatures down to near or slightly below seasonal normals for highs through at least this weekend. Broad cyclonic flow and embedded shortwaves will bring daily chances for showers (maybe a few storms Thursday afternoon), mainly during the afternoon to early evening hours. For the most part, highs will be in the 60s with some embedded lower 70s while lows are generally in the 40s.

The one exception could be in the Friday night to Saturday timeframe with global models hinting at a more organized low pressure that could bring more in the way of widespread rainfall to at least part of the area. There's still some uncertainty within the individual ensemble members (low location/QPF/timing), so the NBM PoPs of 40-50% are reasonable for now. Should this system pan out, temperatures on Saturday would also likely stay cooler and in the 50s.

AVIATION /18Z MONDAY THROUGH SATURDAY/

Clearing this afternoon will allow for conditions to return to VFR by this evening. Some patchy fog may allow for brief periods of low CIGs early tomorrow morning, with VFR expected through Wednesday morning. Restrictions may return with showers and thunderstorms on Wednesday.

Outlook:

Thursday-Friday: Scattered showers and possible a few storms could bring brief periods of MVFR to IFR restrictions, mainly during the afternoon and early evening hours each day. Otherwise, mainly VFR expected.

Friday night-Saturday: Potential for more widespread rainfall and IFR restrictions, but uncertainty remains.

MARINE

Light westerly winds are expected tonight and will continue through the end of the day on Tuesday. An SCA is in effect for elevated seas of 3-6ft through this same timeframe. Winds will become southwesterlies and strengthen to near SCA-levels on Tuesday evening. Elevated seas and winds start to subside by Wednesday morning.

Thursday-Monday...Winds will likely be primarily out of the north Thursday into Friday with low pressure to the east or southeast of the Gulf on Maine. Conditions will mostly remain below SCA levels during this time but can't rule out a brief period of 25 kt gusts Thursday night. A more organized low pressure dropping southward out of Canada may then bring a higher chance of SCA level winds and seas over the weekend.

GYX WATCHES/WARNINGS/ADVISORIES

ME...None. NH...None. MARINE...Small Craft Advisory until 8 PM EDT Tuesday for ANZ150-152. Small Craft Advisory until 8 AM EDT Tuesday for ANZ151-153-154.