Alstead, New Hampshire Weather Forecast Discussion

127
FXUS61 KBOX 111955
AFDBOX
Area Forecast Discussion
National Weather Service Boston/Norton MA
355 PM EDT Thu Sep 11 2025
.SYNOPSIS...
A dry cold frontal passage from north to south takes place
tonight, allowing for a return to cooler onshore flow. Dry
weather with near seasonable temps for Friday and Saturday.
Rain chances return Sunday with highs in the low to mid 70s. We
then return to dry weather and temperatures around seasonable
for early next week.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
200 PM Update:
Key Messages:
* Partly cloudy skies with winds becoming northeast for the
  first half of the night as a dry cold front moves through.
* Lows in the 50s.
Details:
After a couple days of cooler than normal temps...full sun and
warmer low-level temps have allowed for temperatures to reach
into more seasonable readings in the mid to upper 70s at this
hour. High pressure is established over Southern New England,
allowing for north winds around 5-10 mph with occasional gusts
to around 20 mph.
A cold front is working its way through southern Quebec and
northern New England. This is associated with a reinforcing
cooler shot of air tied to a shortwave trough moving into
southeast Quebec and northern ME. This front will be gradually
making its way southward through late evening and midnight;
however the drier air in place will allow for a dry frontal
passage. A shallow layer of moisture could allow for some
increased stratocumulus, but the main effect of its passage will
be winds becoming NE around 10-15 mph near the coasts and around
5-10 mph inland. Lows in the 50s.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
200 PM Update:
Key Messages:
* Clear skies and dry weather prevails, with onshore breezes
  during the day, easing at night.
* Highs upper 60s/near 70 eastern coast, and mid 70s inland.
  Lows mid 40s to mid 50s.
We close out the workweek on a pleasant note from a weather
perspective, as a sprawling ridge of high pressure builds into
Southern New England. With cool and dry advection taking place,
temps will end up being a few degrees cooler than Thursday, with
a easterly onshore flow keeping the eastern coastal areas quite
a bit cooler than further inland. Full sun with highs inland in
the low to mid 70s; but near the eastern coast where onshore
flow will govern, highs upper 60s/spot 70 degrees. Clear skies
and easing easterly winds will allow for good radiational
cooling, but it is more than likely too dry for patchy
nighttime fog to develop. Lows mid 40s to mid 50s.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
Key Messages:
* Dry Saturday with slightly below normal temperatures
* Chance for showers Sunday, potentially lingering through
  Monday.
Saturday:
General upper troughing continues across the northeast Saturday with
high pressure in place bringing dry weather to the region. The
airmass will be a few degrees warmer with light southerly component
flow and local sea breezes for the coastal areas This will support
high temperatures a little warmer than Friday with temperatures in
the low to mid 70s.
Sunday through early next week:
There is a general consensus among ensemble guidance that an upper
level trough drops across the northeastern states on Sunday. This
will provide weak lift along with plume of slightly above normal
moisture across southern New England to bring increased chances for
showers Sunday. Confidence is still lower in the details such as
timing, amounts with some spread among deterministic/ensemble
guidance still. Models are supportive of more scattered coverage
showers, yielding a generally unsettled day for Sunday. Weak warm
advection will bring highs in mid 70s, with some upper 70s possible
for the valleys.
WPC Cluster Analysis depicts good agreement among model guidance for
a fairly stagnant upper pattern in place with a strong/narrow ridge
across the lower Great Lakes Sun/Mon. This may end up favoring a
slower exit of the system. Deterministic/ensemble guidance aren`t in
strong agreement on how long the system sticks around. If the slower
solutions become favored, showers may linger through Monday. As far
as rain totals go, ensembles have rain amounts on the lighter end
overall with a most likely range of trace-0.25".
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
18z TAF Update:
Through 00z Friday: High confidence.
VFR; N winds around 5-10 kt, except SE at BOS.
Tonight: High confidence.
VFR, though a cold frontal passage from north to south from
02-06z will bring a period of FEW to BKN 040-060 bases upon its
passage, along with NE winds 10-15 kt near the coast and 5-10 kt
inland.
Friday and Friday Night: High confidence.
VFR through this period. NE winds 5-10 kt inland, NE to E 10-15
kts for the eastern coastal airports. Winds Fri night to become
light and variable.
KBOS Terminal...High confidence in TAF.
KBDL Terminal...High confidence in TAF.
Outlook /Saturday through Tuesday/...
Saturday through Saturday Night: VFR.
Sunday: VFR. Breezy. Chance SHRA, chance TSRA.
Sunday Night: VFR. Chance SHRA, slight chance TSRA.
Monday: VFR. Breezy. Chance SHRA.
Monday Night through Tuesday: VFR. Breezy. Slight chance SHRA.
&&
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
SCAs continue over the waters through late this afternoon for
waters adjacent to and southeast of Cape Cod and Nantucket with
northerly gusts 20-25 kt and seas 3-5 ft.
NE winds then develop tonight from north to south as a cold
front drops southward; this may bring a brief period of 20-25 kt
gusts to the northeast waters but seems too limited in coverage
and duration to warrant SCAs. Winds tonight should range
between 15-20 kt (with occasional gusts to 25 kt northeast
waters), which then slowly ease into Fri and Fri night. Seas 4ft
or less all waters tonight thru Fri.
Outlook /Saturday through Tuesday/...
Saturday through Saturday Night: Winds less than 25 kt.
Sunday: Winds less than 25 kt. Seas locally approaching 5 ft.
Slight chance of rain showers.
Sunday Night through Monday: Winds less than 25 kt. Seas
locally approaching 5 ft. Chance of rain showers.
Monday Night: Winds less than 25 kt. Chance of rain showers.
Tuesday: Winds less than 25 kt. Seas locally approaching 5 ft.
Slight chance of rain showers.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 8 PM EDT this evening for ANZ254-
     255.
&&
$$
SYNOPSIS...Loconto/Mensch
NEAR TERM...Loconto
SHORT TERM...Loconto
LONG TERM...Mensch
AVIATION...Loconto/Mensch
MARINE...Loconto/Mensch

NWS BOX Office Area Forecast Discussion