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Area forecast discussion 
National Weather Service Caribou ME
120 PM EDT Thu Oct 20 2016

high pressure will move east of the region today. Low pressure
will develop to the west of the area tonight. A secondary low will
develop in the Gulf of Maine Friday night and will slowly lift
across Maine Saturday. The low will slowly lift north of the area

Near term /through tonight/...
1 PM major changes.

Previous discussion... high pressure across the region early this
morning will shift east into the Canadian Maritimes today. Low
pressure moving into the Ohio Valley today will move into western
New England late tonight with an elongated area of low pressure to
extend from the Saint Lawrence River valley to the southern
Appalachians by 12z Friday. Clouds will be on the increase today
with rain to develop by late in the day across northern Somerset
and parts of central and northern Piscataquis and Northwest
Aroostook counties. Highs this afternoon will range from 55 to 60
degrees, perhaps a bit cooler in the far western areas where the
rain develops late day. Periods of rain are expected tonight
across northern areas with some drizzle and scattered showers
across the down east region. Patchy fog is likely to develop
tonight with lows mostly in the 40s.

Short term /Friday through Saturday/...
model consensus continues to show a very wet pattern for the end
of the week. A digging upper trough will push eastward out of the
Midwest, becoming negatively tilted as it moves into the northeast
Continental U.S.. surface low pressure will develop over southern New England
in response to the approaching trough. While there are differences
in exactly where the low will track, overall model consensus
brings the low northward across central or perhaps western Maine.
Meanwhile, the digging trough will lift deep moisture associated
with a tropical wave off the southeast coast northward into New
England. Pwats are progged to reach 1.5+ inches and warm-cloud
depths of 10-12 kft indicate there will be efficient rainfall
processes. Have therefore added the mention of heavy rain into the
Friday night forecast, which is when the aforementioned surface
low tracks near or directly over our forecast area. While exact
rainfall amounts will depend on exactly where the surface low
tracks, current thinking is we'll see widespread rain totals of
1.5 to 2.5 inches. However, wouldn't be surprised to see higher
amounts by the time all's said and done. It should be noted that
our entire forecast area is included in wpc's slight risk of
excessive rainfall for day 3 (12z Fri to 12z sat). Once the low
lifts north of the state, which should occur sometime Saturday
afternoon, drier air will work into the state and allow
precipitation to begin to wane a bit, mainly downeast. Daytime
highs will generally be in the mid 50s to lower 60s, while Friday
night's temperatures will range from the mid 40s in the North
Woods to the mid 50s downeast.

Long term /Saturday night through Wednesday/...
chilly unsettled weather will be the rule through much of next
week. An negatively- tilted upper trough will continue to deepen
through the weekend and will develop a closed low by Sunday
morning. This low will then pinwheel over eastern Canada through
at least Tuesday before finally pushing east Tuesday night into
Wednesday. Given this pattern, expect cool and showery conditions
to persist across the northern half of our forecast area through
the period. Southern areas, including Bangor and downeast, will be
drier though not a whole lot warmer. Daytime highs will be in the
40s through Wednesday, with downeast spots perhaps topping 50 from
time to time. Tuesday looks to be the chilliest day, when some
locations in the North Woods and upper St John valley may not
break 40. Overnight lows, meanwhile, will mainly be in the upper
20s to lower 30s. Given the cold air that will be in place, snow
showers, or at least a rain/snow mix, will be possible through the
period, mainly in the north and west.

Aviation /17z Thursday through Monday/...
near term: VFR today outside of any patchy early morning River
Valley fog. Conditions will lower to MVFR across western Maine
late this afternoon in rain. MVFR will develop across the
remainder of northern and eastern Maine tonight with conditions to
lower to IFR overnight.

Short term: IFR conditions are expected to prevail at all
terminals through the period. Rain, fog, and low ceilings will
persist across the entire forecast area Friday through Saturday as
low pressure crosses the region. The southern terminals may show
some improvement later Saturday through Monday, perhaps up to
MVFR, but can't rule out occasional IFR from time to time.
Northern sites will likely remain IFR.

near term: the wind and seas will remain below Small Craft
Advisory levels into this evening. A southeast wind will increase
tonight with the seas to build to 5 to 7 feet on the coastal
waters after midnight.

Short term: conditions are expected to be poor for the end of
this week and the beginning of next owing to deepening low
pressure that will cross very near the waters and remain over
eastern Canada. A Small Craft Advisory will be in effect at the
start of the short term, running through most of Friday morning.
Winds look to abate for a short time thereafter, into Friday
evening, but seas will remain near 5 ft through the day before
building substantially to 6-8 ft Friday night through Saturday.
Winds will increase Saturday afternoon and remain high through the
rest of the weekend. Gusts could approach gales while seas will
build to 8-12 ft.

Car watches/warnings/advisories...
Marine...Small Craft Advisory from 1 am to 11 am EDT Friday for

Near term...cb/mcw
short term...Hastings
long term...Hastings

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