NWS Forecast Discussion

For Fremont, NH

FXUS61 KGYX 140128

Area Forecast Discussion
National Weather Service Gray ME
928 PM EDT Sun Jun 13 2021

A trough of low pressure will bring a few showers and possibly a
thunderstorm for the beginning of the work week. Clouds and
showers exit to the east by Wednesday with fair weather and
comfortable temperatures expected through Friday. A warm trend
precedes the next chance for precipitation, which will be over
the weekend as a frontal system approaches from the west.


925 PM Update... Made some adjustments to temperatures, winds,
and sky cover based on surface observations and satellite
imagery. High cirrus continues to stream in from the southwest,
especially across northern locations. PoPs were also adjusted
through tomorrow based on the latest near term forecast
guidance. Expecting rain showers to first approach southwestern
NH towards dawn on Monday before gradually advancing to the
north and east through the day. This rain will likely struggle
to reach the surface initially, especially across Maine as the
00Z KGYX sounding shows a dry layer extending up to around 700
mb. As a result, rain onset times were delayed some across
eastern areas. The rest of the forecast remains on track.

Previously... 730 PM...A quick update,
mostly to sky and temps based on current obs. I think going
forecast POPs are good for arrival of showers later tonight
across N and E zones. Lows should bottom midnight or shortly
there after in most spots and remain steady there through the
night generally in the mid 50s to 60.

Previously...An advancing trough of low pressure will allow for
an increase in cloud cover later tonight over western portions
of the forecast area. Sufficient diffluent flow aloft and
increasing moisture will allow for scattered late night showers
over western portions of the forecast area.

Prior to the increase in cloud cover and scattered showers, some
patchy fog is possible, mainly over the Connecticut River

Temperatures will drop into the 50s for overnight lows in most
areas. A few locations in southernmost New Hampshire will remain
at or above 60 degrees.


The trough will continue to approach the region from the west
Monday. Showers will gradually spread east during the day,
reaching the Penobscot River Valley by late in the day. CAPE
values increase as the atmosphere destabilizes and heights fall
aloft, leading to a few thunderstorms during the day.

A southerly flow will increase off the Gulf of Maine. This will
keep temperatures a little cooler along the immediate coastline
and unfortunately lead to a dampening effect of the well needed

A few showers and thunderstorms will continue into Monday night.
A few of the storms Monday evening may contain pea sized hail as
heights continue to fall across the region. By late Monday
night, both the surface and upper level trough will remain west
of our forecast area.


A long wave trough will be positioned over the eastern CONUS Tuesday
with the trough axis just to our west. A vort maxima or two will
rotate through the base of this trough along with a surface trough
setting up over New England Tuesday into Tuesday night. This will
bring periods of showers and a chance for thunderstorms centered on
Tuesday afternoon with a drying trend expected into Wednesday.  The
long wave trough will be stubborn to migrate eastward Wednesday
into Thursday keeping temperatures near their seasonal norms
with highs in the 60s north to 70s south. Ridging aloft builds
in Thursday night into Friday for a warming trend Friday into
Saturday. Another trough approaches from the west Saturday with
a frontal system crossing the area Saturday into Sunday.

Tuesday will start off with mostly cloudy skies with pockets of
showers and fog. CAMs and global models indicate that cloud
cover will thin with some breaks of sun late Tuesday morning
allowing for the atmosphere to destabilize as lapse rates
steepen from the approaching trough axis. This will lead to
SBCAPE to climb into the 500 to 1000 J/kg range early Tuesday
afternoon. As CAPE increases the best shear will be shifting
offshore placing the best overlap over the foothills and Lakes
Region of New Hampshire through the coastal plain. Chances for
thunderstorms will increase late Tuesday morning into the
afternoon as a surface trough sets up ahead of a cold front in
Canada. Chances for widespread severe convection look to remain
low as parameters don`t quite overlap well. However, there
remains uncertainty with timing differences of vort maxes
translating through the long wave trough and can`t rule out the
chance for a few strong storms. Areal coverage looks widely
scattered with chances that some towns remain dry Tuesday.

The long wave trough does not move much Wednesday into Thursday
as an upper low closes off to our north. Drier air will filter
in Wednesday on northwest winds, although cyclonic flow aloft
will lead to some afternoon clouds with a slight chance for a
shower in the mountains. Thursday will be similar to Wednesday
as the upper trough slowly shifts off the East Coast. Ridging
aloft builds in Thursday night into Friday allowing for highs to
climb into the mid 70s to low 80s Friday into Saturday. The next
upper trough looks to swing through the Great Lakes Saturday
with the potential for a frontal system to cross the area
Saturday afternoon into Sunday.


Short Term...VFR conditions expected in most areas tonight.
There may be some late night patchy fog in the Connecticut River
Valley briefly lower restrictions to IFR. Showers late tonight
gradually spread east on Monday with generally MVFR conditions.
A thunderstorm in possible. Areas of IFR and LIFR conditions
develop Monday night in showers, thunderstorms and patchy fog.

Long Term...Areas of IFR/LIFR Tuesday morning in showers and fog
with some improvement to MVFR/IFR late Tuesday morning into
early afternoon. Scattered showers and -TSRA late Tuesday
afternoon will bring pockets of restrictions with a drying
trend expect Wednesday for IFR through the end of the work week.


Short Term...An approaching trough will allow for a southerly
wind to increase overnight. There may be a couple gusts near 25
kt during the midday hours on Monday as the southerly gradient
briefly increases. Fog will lower visibilities Monday night as
moisture increases over the Gulf of Maine.

Long Term...There will be some reduced visibility Tuesday
morning in scattered showers and fog with southerly winds.
Southerly winds will shift out of the northwest Tuesday night
into Wednesday for a drying trend.





NEAR TERM...Cempa/Tubbs

NWS GYX Office Area Forecast Discussion