NWS Forecast Discussion

For Fremont, NH

FXUS61 KGYX 060006

Area Forecast Discussion
National Weather Service Gray ME
706 PM EST Tue Dec 5 2023

Light snow showers possible tonight for the southern half of
New Hampshire, then a drying and cooling trend progresses into
Thursday as high pressure builds across New England.
Temperatures moderate late week and into the weekend as the high
moves offshore. A strong low pressure system moves through the
Great Lakes Sunday night and Monday, with wind and some rain
impacts increasingly likely during this timeframe. High pressure
returns toward the middle of next week.


7 PM...Based on latest meso models and obs /especially radar/ it
seems unlikely we`ll see any SHSN in S NH this evening, and
even after midnight, what fall looks to be pretty isolated and
light, so have backed off POPs some overnight. Also made a few
adjustments to T/Td/Sky/Wind based on current obs, but nothing
that affects the forecast in any appreciable way.

Previously...Stubborn clouds continue to hold on this
afternoon, but drier northerly flow is helping to break things
up in our northern and western zones. Southern zones will see
clouds thicken again this evening as a similar set up to last
night occurs, with a 500 millibar trough digging in and
interacting with an inverted surface trough nosing in from low
pressure moving offshore from the Carolinas. Tonight it looks
like the forcing for ascent will be more focused on southern New
Hampshire, but similarly any snow looks very light with little
to no accumulation. Temperatures up north, where clouds look to
thin, fall into the teens and single digits and down south where
clouds stick around, only cool to the 20s.


Clouds clear out from north to south as the trough exits and
high pressure over Quebec noses in. They don`t clear out quick
enough to get high temperatures much above the mid 30s south of
the mountains and mid 20s to the north however.

Clouds do clear out for the evening and overnight allowing
temperatures to fall into the single digits up north again, and
teens down to the coast. Clouds will begin to thicken again towards
daybreak Thursday as a warm front approaches.



Broad high pressure gradually moves through during the later
portions of the work week and into the early weekend. The high
moves offshore through the weekend as low pressure develops
across the south central US. This low deepens as it moves
northeastward through the Great Lakes Sunday night through
Monday. Broad high pressure then builds eastward into the
Northeast going into the middle of next week.


A broad axis of high pressure crosses New England on Thursday
through Friday. A seasonably cool day is expected for Thursday,
with a moderating trend starting by Friday. Despite WAA
beginning, lingering high pressure allows for decoupling and
another night of radiational cooling Thursday night. This brings
lows into the single digits and teens across the area. Typical
radiational cooling spots with snow cover also have a shot at
dipping below zero for one more night, but this forecast is
already much lower than NBM guidance, without ignoring the
chance that clouds could spoil the cooling potential.

The center of the high moves offshore going into the weekend,
continuing the warming trend. However, the main focus remains
the developing low pressure center across the southern tier of
the country. Low pressure develops across the south on Saturday,
deepening as it moves northeastward into the Great Lakes
through Sunday. The low continues to strengthen as it passes
well to our west Sunday night through early Monday.

There remains fairly high confidence in a mainly rain and wind
potential for the area with system, but the degree of intensity
remains in question. There has been a trend in the Euro the last
few runs for the storm to take longer to develop as it moves
northward, and a slight trend to track back farther east. The
slower to develop trend has little impact on our outcome at this
point as the low remains sufficiently strong by the time it
reaches the Great Lakes, but it serves as a reminder that the
details of the system and how organized it is by the time it
reaches is not set yet.

At this point the rainfall doesn`t look overly impressive, with
most models putting out QPF between 0.5in to 1.5in. This would
increase if we get into more of the stratiform shield, but there
is little guidance supporting this at this time. The most
potentially impactful factor looks to be wind gusts. How deep
the low gets and how close it passes to our west remain the
deciding factors of how strong the wind gusts will be. At a
minimum gusty wind are expected along the coast, with the upper
end range currently coming in below last December 23rd`s storm.
So we will continue to monitor the trends over the next few
days, but it is reasonable to expect that there will at least be
some wind impacts Sunday night into Monday.

High pressure and cooler air then spreads eastward toward the
middle of next week.


Short Term...VFR/MVFR ceilings prevail this evening, but New
Hampshire terminals could see some light snow showers overnight that
could bring about IFR visibilities. Conditions improve and remain
mostly VFR across the area through Wednesday.

Long Term...VFR conditions prevail through Saturday night, then
ceilings gradually lower on Sunday as a storm approaches. IFR
conditions with rain, and southerly wind gusts in excess of
30kts are likely Sunday night into Monday. Conditions improve
Monday night, with mainly VFR expected by Tuesday.


Short Term...Snow showers are possible over the waters overnight
tonight. Otherwise, winds and seas remain below SCA thresholds
through Wednesday.

Long Term...High pressure remains across the waters from
Thursday into Saturday. A developing storm moves across the
interior Northeast, with gale to storm force southerly winds
possible Sunday night and Monday.




NEAR TERM...Baron/Cempa

NWS GYX Office Area Forecast Discussion