Topsham, Maine 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

279
FXUS61 KGYX 070104
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
804 PM EST Fri Mar 6 2026

.WHAT HAS CHANGED...
Expanded the winter weather advisory farther south into NH for
the overnight hours given temperatures just below freezing with
drizzle falling.

&&

.KEY MESSAGES...
1. Prolonged period of near-freezing, dreary weather expected
through Saturday.

2. Warm temperatures next week will bring about a spring thaw,
greatly reducing the snowpack and causing some ice movement on
area rivers. The flood risk remains low, but with expansive
river ice across the area levels will have to be monitored
closely.

3. A chance for widespread precipitation starts the the second
half of next week with temperatures returning closer to seasonal
normals.

&&

.DISCUSSION...
KEY MESSAGE 1 DESCRIPTION...

The morning snow has moved out and warm advection is beginning
in its wake. Visible satellite is showing clear northward
movement of cloud cover at this hour and gradual upglide over
the cold surface air is expected thru tonight. This should
establish a nice low cloud deck that at least banks up against
the mtns. There are two main concerns as this happens this
evening. One is that weak ascent and shallow moisture will
promote drizzle formation tonight. With temps largely remain
below freezing this will mean freezing drizzle. Added to this
threat is that some warm advection showers are forecast to
arrive around daybreak Sat where temps are most likely to remain
below freezing. With the light ice accumulation forecast, I
have issued a Winter Weather Advisory. It is possible that if
temps are cooler than forecast this may need to be expanded. The
second concern is for fog development. Hi-res guidance is
fairly bullish on this forming around or after midnight. If we
can get those dewpoints to near freezing over the snow this
should result in at least some areas of fog. I cannot rule out
the chance that fog is dense in places and we may have to hoist
a Dense Fog Advisory.

KEY MESSAGE 2 DESCRIPTION...
The overall pattern to start next week favors mean troughing
with a strong Atlantic ridge in place, but a couple days of
southwest flow looks to warm 850 mb temperatures to around +3-6C
which is nearly 20 degrees above normal for this time of year.
This should be good for widespread temperatures topping out in
the 50s on Monday and Tuesday. At this point the confidence in a
couple warm days is high, however there are some factors that
may limit temperatures both days from going quite as high at
what the NBM and other models have been advertising. Low
pressure slides just north of the area Monday which could add
some clouds into the mix. Whether it`s enough to actually stunt
warming will have to be fleshed out as we get closer, but we
usually seem to end up with more clouds than models show when we
are in the middle ground with low pressure to the north. Clouds
won`t be an issue Tuesday as high pressure begins to push in,
but we will have a cold front on approach as well. This would
most likely impact temperatures in the north as the front likely
doesn`t push much past that point during the day, and the
difference would be 40s versus 50s.

Bottom line: It`s going to feel warm and we are going to see
significant reductions in snow pack and some movement in river ice
as a result. A key takeaway here is that dew points stay in the mid
30s so melt is going to be controlled and therefore the flood risk
remains low (but it is never zero). We do have expansive river
ice across the area which will need to be monitored, but latest
observations suggest that it is still around a foot thick on the
larger mainstems. Ice of that magnitude would require rapid
river rises to break that up and that is not anticipated with
the little QPF and melt that is anticipated through the forecast
period.

KEY MESSAGE 3 DESCRIPTION...
Low pressure rides along the aforementioned front into New
England late Tuesday into Wednesday. Fairly large model spread
on 850 mb temperatures during this time is leading to some
uncertainty in precipitation types along models. The GFS and
Canadian quickly usher in strong high pressure to the north and
expect it to start cooling the column leading to more mixed
precipitation while the Euro keeps warm air locked in at the
surface, and thusly keeps the dominant precipitation mostly
rain.

Regardless of how quickly models think it occurs, confidence is
high that we return back to more seasonable temperatures for
the second part of the week with temperatures looking to top out
in the the mid- to upper 30s during the day, and bottom out in
the 20s and teens at night.

&&

.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
Widespread MVFR CIGs will begin to lower this evening from
south to north as onshore flow and warm advection increase
moisture over cold snow pack. Widespread IFR or lower conditions
are expected south of the mtns. Freezing drizzle will also be
possible at all TAF sites until temps begin to warm Sat morning.
HIE may remain VFR or MVFR as low cloud cover struggles to make
it past the mtns.

Outlook:

Sunday: Becoming VFR, except in the mtns where MVFR CIGs may
linger. Westerly surface gusts to 25 kt possible in the
afternoon.

Sunday night-Tuesday: VFR conditions expected.

Tuesday night: Conditions becoming MVFR/IFR as rain and snow move
into the area overnight.

Wednesday-Wednesday night: MVFR/IFR conditions continue. There is
uncertainty in precipitation type for this time period, so
widespread IFR is not out of the question if the forecast trends
colder and terminals see more of a mix or snow.

&&

.MARINE...
Northeast winds will gradually turn east and then southerly
thru Sat. Seas are expected to remain above 5 ft even while
winds diminish, however eventually increasing southerly winds
ahead of a cold front will also begin gusting above 25 kt again
Sat. The front will cross the waters Sun with winds and seas
gradually diminishing. SCA has been extended thru Sat for all of
the outer waters.

Wave heights will remain around 5-6ft into Tuesday morning. A
brief break in SCA conditions occurs Tuesday afternoon and night
before winds and seas ramp up Wednesday as a disturbance moves
through the Gulf of Maine. There is even some suggestion that
gale force gusts may be possible at times through Thursday. Seas
fall below 5ft Thursday afternoon, but winds gusts remain
25-30kts through Friday.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Winter Weather Advisory until 10 AM EST Saturday for
     MEZ007>009-012>014-018>022-033.
NH...Winter Weather Advisory until 10 AM EST Saturday for
     NHZ001>006-009.
     Winter Weather Advisory until 5 AM EST Saturday for NHZ008-010-
     012-013-015.
MARINE...Small Craft Advisory until 5 PM EST Sunday for ANZ150-152>154.

&&

$$

DISCUSSION...Baron/Ekster/Legro
AVIATION...
MARINE...