Area Forecast Discussion
Issued by NWS Portland, ME

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FXUS61 KGYX 301926 CCA
AFDGYX

Area Forecast Discussion...Corrected typo
National Weather Service Gray ME
326 PM EDT Sun Apr 30 2017

.SYNOPSIS...
A warm front will remain south of the region tonight and Monday
and will be followed by an occluded front Monday night. A
trough of low pressure will approach from the west on Tuesday
and will cross the region Wednesday. High pressure builds in
from the west Wednesday night and before shifting offshore on
Thursday. Low pressure approaches from the southwest and moves
up the east coast for the end of the work week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Clouds have spread across the region this afternoon accompanied
by scattered showers. These clouds are the leading edge of a
broad warm front extending from our area back across New York and
southern Ontario to the Great Lakes ahead of a strong cyclone in the
middle of the CONUS. This front will slowly move eastwards overnight
spreading heavier rain into the northern portion of our region. Most
widespread and heaviest rainfall will be in the mountains where
around an inch of QPF is expected.


&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
Monday the shower activity will decrease in the north with just
a few scattered showers as our region is left in the warm
sector of the cyclone. Sadly it won`t be very warm at the
surface as north to easterly flow off the Gulf of Maine will
keep temperatures in the upper 40s. In the CT valley of NH and
along the Mass border the warmth will creep in with
temperatures reaching the mid 60s. A cold front will approach
the region on Monday night and move through early Tuesday
morning with an additional 0.5" of rain.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
On Tuesday a broad area of upper level low pressure will be
filling and shifting northeast out of the Great Lakes region and
into southern Quebec Province. The system will become negatively
tilted as it weakens to an open wave late Tuesday night. Tuesday
morning a pre-frontal trough will be moving east through Maine
along with a line of showers and some embedded thunderstorms.
Surface low pressure will be nearly vertically aligned with the
upper level system, with most of the surface energy moving
north of us as well. Therefore not expecting any severe weather
but there could be some heavy downpours along the boundary.

Behind the pre-frontal trough but ahead of the actual cold
front (essentially a wind shift to the NW), we will see warming
during the day, with sections of southern NH and interior Maine
reaching the upper 60s to lower 70s.

WSW/near zonal flow will be in place Wednesday through
Thursday. Skies will clear out over the coastal plain first
before clearing occurs elsewhere on Wednesday. Low clouds and
showers will linger over the mountains through late Wednesday
night. Clouds return quickly Thursday night ahead of the next
system. Temperatures for this 2 day period will range from the
50s in the mountains to the 60s south.

Low pressure originating in the southern Plains will eject NE
Thursday and extend a warm front into New England with
precipitation developing by Thursday night in southern NH. Our
area will remain in the warm sector Friday and Saturday, with
additional showers/drizzle in the warm advection regime. Models
have backed off on developing a coastal low as this system
deepens, but a stronger surface reflection will move into
southern Canada by Sunday morning. This will keep northern New
England in onshore flow/somewhat dreary weather for the
remainder of the weekend. A a pre-frontal trough passage is
likely sometime Sunday with some drying occurring.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Short Term...Conditions will steadily decrease from VFR to MVFR
overnight and into IFR by tomorrow. Rain overnight in the north
may briefly mix with snow or freezing rain at elevation

Long Term...IFR/LIFR ceilings continue Tuesday morning with
improvement to VFR Tuesday. Areas of MVFR ceilings linger in
the mountains Tuesday night through Wednesday. VFR conditions
will prevail Wednesday night through Thursday with deteriorating
conditions Thursday night through Friday with some +SHRA.

&&

.MARINE...
Short Term...
Winds will increase behind the cold front late Monday night
into Tuesday and a Small Craft Advisory will likely be needed.

Long Term...Marginal SCA conditions are possible Tuesday into
Wednesday, mainly in the offshore waters. Stronger SCAs are
possible Friday afternoon into Saturday as a coastal low passes
nearby.

&&

.FIRE WEATHER...
Things moisten up substantially through Monday with low clouds
and drizzle expected. Rainfall of around an inch is possible
across northern NH and the western ME mountains late tonight and
early Monday. Additional rainfall is expected Tuesday as well as the
end of the work week.

&&

.HYDROLOGY...
Some concern for river flooding on the Kennebec over the next 48
hours. Most of the rainfall in the next 24 to 48 hours will
focus directly on the upper Kennebec basins. Moosehead lake is
already very full and flows going into the Kennebec remain
high. Downstream flooding is possible particularly at Skowhegan.


&&


.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...None.

&&

$$

NEAR TERM...Curtis
SHORT TERM...Curtis
LONG TERM...Hanes



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