Sanford, Maine 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

136
FXUS61 KGYX 131842
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
242 PM EDT Wed Aug 13 2025

.SYNOPSIS...
Hot weather continues today before a cold front cools things
off a bit for Thursday. Scattered thunderstorms develop both
this afternoon and Thursday, some of which may be strong.
However widespread wetting rainfall is unlikely, and most
locations will see little aid to growing deficits. The weekend
looks to be dry at this time with a warming trend this weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Showers and thunderstorms are developing to the west,
approaching western NH at this hour. Advancement east has been
slow, but pre-frontal trof will accelerate showers and storms
as the day goes on.

RAP analysis shows limited instability over bulk of the forecast
area. This aligns with limited cumulus development so far today.
Where moisture is more abundant, this field is thicker...across
mostly western locations. Expect instability to increase
resulting in isolated to scattered thunderstorms slowly moving
east this afternoon. SPC Marginal Risk continues to highlight
the threat for gusty to strong winds where taller cores may
collapse due to lack of shear and narrow updrafts.

Storm intensity wanes this evening with loss of daytime heating.
By then, HRRR runs have been bringing showers and storms through
the western ME mountains and southern NH. Overnight, some
isolated showers may continue given remaining elevated
instability.

As far as rainfall, storms have a limited footprint, and any
benefit to the increasingly dry conditions will be minimal.
While storm motion is slow, leading to showers or storms
training or backbuilding, precip efficiency parameters are not
overly concerning. More progression may also be derived if
clusters can form ahead of an induced cold pool.

Under cloud cast, lows tonight will be mild, in the upper 60s to
around 70.

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
Cold front will make its push across the forecast area Thursday.
Temps again warm into the upper 80s, but not go much higher.
Showers and thunderstorms develop ahead of the front. Depending
on its progression and timing in the afternoon, areas with
chances of thunderstorms may still include much of the interior
and coast. Storms may be more isolated tomorrow, pushing towards
the coast by late afternoon.

Similar storm environment exists with decent CAPE and PWATs, but
limited shear and mid level lapse rates. Some question as to how
much moisture will be added to the BL, which could reduce gusty
wind threat for Thursday`s storms.

Once the front slides through, precip should shut off quicker
than this evening. Temperatures will also be more refreshing
with lows into the lower 60s for most locations, with 50s across
the mountains.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Temperatures are expected to be in the low to mid-80s for
Friday, with a clear and dry day expected.

Dry and warmer weather is expected to continue through the
weekend, as a 500mb ridge builds in across the central US. An
upper-level low over Quebec slides down into the Canadian
Maritimes on Sunday, potentially allowing for a couple showers
and storms to pop up across the interior during the day Sunday.
Prior to the frontal passage, the weekend is expected to see a
warming trend. Highs look to be in the mid to upper 80s Saturday
and then lower 90s Sunday.

The aforementioned upper-level low should bring lasting cooler
weather into the area, with high pressure building in for next
week. High temperatures next week look to be in the mid to upper
70s. High pressure should hang on all week, leading to
prolonged dry weather. Very dry weather next week will likely
worsen the drought conditions that are being felt at the moment.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
Short Term...SHRA and TS push east across NH this afternoon and
early evening. These may include gusty, erratic winds and
rainfall that reduces visibility. IFR deck has docked with the
midcoast of ME, and will likely advance inland as daytime
heating abates. Would expect some build down fog from this as
well to affect RKD and AUG overnight. Uncertainty on valley fog
development tonight, but some lower stratus is possible for LEB
to HIE late. Another round of SHRA and TS for interior and
coastal terminals Thursday as cold front finally slides east.

Long Term...VFR generally expected through the entire period. A
few brief windows of lowered restrictions are possible on
Sunday evening as a few thunderstorms move through the area.

&&

.MARINE...
Short Term...Below SCA conditions expected as some showers
approach this evening. Cold front will near the waters during
the day Thursday with wave heights generally 1 to 3 ft from
bays/harbors out to the outer coastal zones. Southerly winds
today and tonight turn NW Thursday evening.

Long Term...Northerly winds pick up briefly on Friday morning,
with 12-20kt winds expected. SCA issuance is possible for winds.
Winds slacken and become light and variable by the end of the
day on Friday and stay light through daybreak Saturday. Saturday
afternoon, winds pickup from the south, with 7-12kt winds
expected. Winds shift to southwesterlies by Sunday morning, with
wind speeds remaining in the 7-12kt range. By Monday morning,
winds shift to northerlies at 9- 14kts. Seas will remain at
2-4ft through the entire forecast period.

&&

.CLIMATE...
Daily record highs and year(s) for Portland, Augusta, and
Concord.

          Portland          Augusta       Concord
Aug 13    99F (1947)        94F (2004)    99F (1944)

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Heat Advisory until 8 PM EDT this evening for MEZ012>014-
     018>022-033.
     Air Quality Alert until midnight EDT tonight for MEZ018>028.
NH...Heat Advisory until 8 PM EDT this evening for NHZ010-012-013.
MARINE...None.

&&

$$


NEAR TERM...Cornwell
SHORT TERM...Cornwell
LONG TERM...Palmer