Area Forecast Discussion
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FXUS61 KGYX 280113 AAC
Area Forecast Discussion...UPDATED
National Weather Service Gray ME
913 PM EDT Thu Oct 27 2016
Low pressure will slowly move east through the region tonight and
Friday, bringing heavy rain for most of the region with snow at
the highest elevations. Winds will be gusty at the coast. A ridge
of high pressure will build in from the west Friday night. A weak
trough moves through Saturday which drags a cold front through the
area late Sunday. High pressure will build in from the west Monday.
Low pressure will pass by well to our north midweek.
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
-- Changed Discussion --915 PM update...
Large area of light to moderate rain and drizzle is now over most
of NH and a good portion of western Maine. Temperatures remain
above freezing within the CWA while just into MA and VT snow is
falling. Accumulations as much as 6" have been reported so far.
Stronger dynamics will develop overnight and as temperatures fall
across the higher terrain precipitation will mix with and
changeover to snow. Near Long Island sound a coastal low pressure
system is beginning to form.
No major changes to the forecast. Updated to include latest
thermal and moisture trends.
635 PM update...
Ocean effect showers continue ahead of a warm frontal boundary
this evening and are delivering moderate rainfall in some cases.
Visibilities may go down briefly in these showers which are mainly
affecting western Maine and east towards the Mid coast. Isobars
are beginning to kink along the coast in anticipation of surface
low formation overnight which will prompt a more substantial
precipitation shield shifting ENE with time...especially after
midnight and during the morning commute. This update adjusted
temperatures and dew points as well as P-type. Snow is noted just
across the border from NH into VT...but as the warm front
advances any snow or rain/snow mix should be confined to the
foothills and mountains and perhaps portions of the CT River
A potent short wave trough will approach the region tonight allow
for rapid surface cyclogenesis over southern New England tonight
which will move into the Gulf of Maine on Friday. As a result
there are a few relatively minor impacts to talk about,
including snow, wind, and rain.
Precipitation will continue to gradually spread northeastward
across the CWA this evening, with a good chunk of the
precipitation type being rain. However, at elevations mainly
above 1000 FT in W/SW NH some light snow accumulations are likely
this evening (generally less than 1 inch).
Also, scattered ocean-effect showers will move inland on the Maine
coast from time to time through the early evening hours.
As pressure falls rapidly occur over southern New England tonight
(mainly after midnight), forcing for ascent will correspondingly
increase as well causing a more rapid northeast advancement and
higher intensity of precipitation. The column should be cold enough
for snow at higher elevations across northern NH and the western ME
mountains, with snow amounts highly dependent on elevation. It`s
possible that from late tonight through Friday that elevations above
2500-3000 FT will see greater than 6 inches of snow. Below that
level, amounts will be lighter. Have issued a winter weather
advisory mainly for snow for northern Franklin and central Somerset
counties, due to the early nature of the snowfall and the potential
for a period of wet snow that may weigh down branches and power
Rainfall is expected for the vast majority of the populous, with
the rain increasing in intensity, especially late tonight and
Friday morning. Strong ascent owing to large scale and mesoscale
forcing (including a potential coastal front), should allow for
heavy rainfall, most likely on the coastal plain, with 1 to 2
inches expected through midday-ish Friday. It would not be
surprising to see upwards of 2.5 inches in spots due to strong
nature of the inflow pointed toward the coast. Some localized poor
drainage flooding is likely during the morning commute, especially
where leaves clog storm drains.
Winds will be another issue as well. Strong onshore flow should
begin to affect the coast...most likely the immediate coast...late
tonight and Friday morning as strong pressure falls aid in
generating an onshore jet. The strongest winds (gusts to 50 mph)
are most likely on the Midcoast of Maine during this time as the
system matures (and subsequently resulting in the issuance of a
wind advisory). Further south along the coast, winds should not
be quite as strong but still could gust up to 40 MPH.
The rain and wind will subside from S to N during the day on
Friday, with only linger showers expected for southern zones
during the afternoon hours. Rain and snow should continue in the
mountains, but probably be more rain than snow as the day
progresses outside of the highest elevations.
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.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
Low pressure will gradually move
away from the region Friday night with gradual clearing and gusty
NW winds. Clouds may increase late friday night as the next short
.LONG TERM /SATURDAY THROUGH THURSDAY/...
A fast moving flow aloft will have numerous weak systems embedded
along it and several of these will pass through during the
outlook period. Timing of these systems will be difficult and
varies some from model to model.
A weak trough moves through the westerly flow aloft Saturday and
will produce scattered showers mainly in mountain areas with maybe
a few isolated showers reaching southern areas. Models indicate a
much stronger digging trough moving through the Northeast on
Sunday dragging a strong cold front across the region by later in
the day. Scattered showers are expected with this cold front and
then followed by clearing and colder temperatures by late Sunday
night. Winds will be gusty from the northwest behind the cold
front Sunday night. Monday high pressure quickly builds east
across the area allowing winds to quickly diminish as the center
of high pressure crests over the area by Monday afternoon and then
moves off the coast Tuesday afternoon. Another fast moving trough
will move north of the area Tuesday night allowing a warmer
southwest flow to develop Tuesday night into Wednesday. Another
short wave approaches late Wednesday possibly bringing more
showers to the area. Stayed very close to superblend model
.AVIATION /01Z FRIDAY THROUGH TUESDAY/...
Short Term...Conditions will lower to IFR to LIFR overnight with
moderate to heavy rain in most places, especially on the coastal
plain. Snow will be found at the highest elevations. Gusty
easterly winds will be found at the coastal terminals late tonight
and Friday morning with LLWS possible. Improving conditions are
foreseen gradually from S to N across the region Friday afternoon
Long Term...Some MVFR possible mainly in the mountains Saturday
and all areas Sunday afternoon with with cold frontal passage that
occurs late Sunday afternoon. VFR conditions for early next week.
Short Term...Gales continue for all waters tonight into Friday for
frequent gusts around 45 kt. Seas on the ocean waters should build
to in excess of 10 feet. Winds switch to NW and slowly diminish
later Friday afternoon and night.
Long Term...Winds and seas remain light Saturday and Sunday. A
cold front moves across the waters Sunday night with strong gusty
northwest winds behind the front that continue through early
Monday. By Monday afternoon winds quickly subside and become light
as high pressure builds over the waters.
Some minor splashover is possible during Friday morning`s high
tide. However major problems are not expected due to relatively
low astronomical tides.
-- Changed Discussion --ME...Wind Advisory from 4 AM to 2 PM EDT Friday for MEZ025>028.
Winter Weather Advisory until 4 PM EDT Friday for MEZ008-009.
MARINE...Gale Warning until 8 PM EDT Friday for ANZ150>154.
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