Hermon, Maine 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

208
FXUS61 KCAR 261330
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
930 AM EDT Tue May 26 2026

.WHAT HAS CHANGED...
- 9:30AM UPDATE...Have made POP adjustments for this afternoon
  based on the Hi-Res CAMs expecting scattered to numerous
  showers to develop later this afternoon as a 500mb shortwave
  approaches from the NW. Increased scattered thunderstorm
  coverage across Northern Maine based on the latest NBM 5.0
  thunderstorm probabilities. Hi-Res CAMs continue to show low
  end SBCAPE this afternoon due to low level dry air. Looking at
  generally around 500j/kg SBCAPE and increasing 0-6km bulk
  shear. Typically in high shear, low CAPE days we generate some
  thunderstorms but very few get strong enough to produce
  damage. Increased confidence in the Hi-Res CAMs to add gusty
  wind wording to storms later this afternoon mainly confined to
  the St. John Valley. It is here where modeled soundings show
  50-60kt of potential wind to be mixed down which confidence is
  increased given the inverted V signature. Additionally with
  >100 m2s2 helicity confidence in some more robust cores
  possible. Timing will be everything, the best chance of storms
  will be near sunset which instability will quickly dissipate
  as the sun goes down but widespread showers remain.

&&

.KEY MESSAGES...
1) Showers with possible thunderstorms late this afternoon and
early this evening over Northern Maine.

2) Cooler than normal temperatures are expected Thursday
through next weekend, along with the chance for showers.

&&

.DISCUSSION...
KEY MESSAGE 1...Showers with possible thunderstorms late this
afternoon and early this evening over Northern Maine.

KEY MESSAGE 1 DESCRIPTION...
Today will be the warmest day of the week with highs in the
upper 70s and lower 80s. This will be dramatically warmer than
yesterday. The warmer airmass will be drawn in from the
southwest ahead of an approaching low pressure from the
northwest. Instability increases ahead of the low pressure,
enough for the risk of some storms in the far north/northwest
mid to late afternoon. One problem is that the system arrives
just a bit late to tap into the maximum daytime heating. The
best dynamics occur near or just after sunset. This means that
while there may be some storms in the north, most likely they
will not be severe as we will be losing our daytime heating as
the bulk of the shower/storm activity moves through Northern
Maine. Feel pretty confident that the far north will get some
decent rain totals very late afternoon/early evening, with some
places from Caribou north topping one half inch. One thing to
watch for is if any convection can fire mid-afternoon ahead of
the main area of showers/storms further northwest. If we get
any of these discrete cells out ahead, as a few CAMs have hinted
it, they could be on the stronger side. But more likely, we
will just see some showers with a few embedded non-severe storms
in the far north late afternoon/early evening.

Further south, little if any rain is expected this
afternoon/evening, as the low pressure center and best upper
level dynamics will be tracking from NW to SE over far Northern
Maine.

KEY MESSAGE 2...Cooler than normal temperatures are expected
Thursday through next weekend, along with the chance for
showers.


KEY MESSAGE 2 DESCRIPTION...
An unsettled weather pattern is expected mid-week right through
next weekend as upper level troughing persists across northern
New England. This will result in temperatures remaining
generally below normal for this time of year, with the exception
of Wednesday, when high temperatures are actually expected to
be above normal over Downeast, while the cooler air begins to
work into Northern Maine. With the upper trough and cold air
aloft across the area, there will be the chance for a few
showers from time to time Wednesday to Sunday, especially
during the afternoon hours with diurnal instabilty.

One thing to watch is a strong slow-moving vertically stacked
low pressure system that is likely to pass from north to south
just west of us from late Friday into Saturday. Right now, the
majority of solutions keep the heavier rain just west of us,
with our area just getting scattered showers. However, a notable
minority bring the low pressure a touch further east, and if
this happens, we could get a period of steadier rain with totals
possibly over one inch. The greater chance for the more
significant rain would be western and southern portions of our
area, such as from Greenville to Bangor to the Hancock County
coast.

Also of note with the below average temperatures, readings will
be especially cool at higher elevations. In fact, we can`t rule
out some snow at some point in the Thursday to Saturday period
for higher elevations. With people starting to hike many of
Maine`s peaks, things can get quite dangerous when wintry
weather is encountered and people are expecting summer
conditions. Be sure and check our recreation forecasts at
weather.gov/car/recreation the day before and the early morning
of your planned hike.

One final issue to keep an eye on is the potential for frost.
Right now, odds favor no frost for the Thursday night to
Saturday night period due to more cloud cover in general, but
if we get a clearer night, frost could occur.

&&

.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
Today...VFR. Any localized IFR/LIFR early this morning should
dissipate by 12z. Mid to late afternoon, from PQI north the
potential for TS exists, with SHRA likely. Winds W to SW
increasing to 10 kts, and higher gusts around TS possible in
the late afternoon at northern terms.

Tuesday Night and Wednesday...Generally MVFR/IFR at Aroostook
terminals, and generally VFR with possible MVFR at Downeast
terminals such as BGR/BHB. SW wind shifting to the NW and
increasing to 10 kts with gusts to 20 kts Wednesday afternoon.

Wednesday Night to Saturday...Mainly VFR BGR/BHB and MVFR or
VFR HUL/PQI/CAR/FVE. Showers possible. N wind 5 to 15 kts with
higher gusts during the day.

&&

.MARINE...
Seas fall below small craft levels later today into tonight and
should remain below small craft levels into the weekend.

Winds generally below small craft levels, but there is a 40
percent chance of small craft winds to 25 kts from the NE
Friday night/Saturday.

&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...Small Craft Advisory until 8 PM EDT this evening for ANZ050-
     051.

&&

$$

DISCUSSION...TF/JS
AVIATION...TF