Area Forecast Discussion
Issued by NWS Portland, ME

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
000
FXUS61 KGYX 261448 AAC
AFDGYX

Area Forecast Discussion...UPDATED
National Weather Service Gray ME
1048 AM EDT FRI AUG 26 2016

.SYNOPSIS...
A cold front will move through northern New England this morning.
Showers and a few thunderstorms are expected along the front, with
winds shifting to the northwest in the afternoon as the front
moves offshore. It will be hot with temperatures climbing into the
upper 80s to low 90s. High pressure builds in out of Canada on
Saturday with another warm day in the 80s. High pressure moves
east on Sunday as another front approaches from the west. This
front will cross the area Sunday night into Monday with another
round of showers and thunderstorms.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1045 am Update...
Showers are moving across southern and central portions of the
forecast area as a cold front translates south. Most locations are
seeing less than a tenth of an inch but some of the heavier
showers have measured around a third of an inch. Drier air is
working in from the north but temperatures are still expected to
reach the mid to upper 80s inland with upper 70s/lower 80s across
the mountains. This is more of a temperature gradient than was
previously forecast. Also the coast will see a slight onshore
breeze as the front stalls nearby. Minor adjustments were made to
temperatures...dew points...winds...and weather grids. Thunder was
taken out for the next few hours but isolated thunder may be
possible later this afternoon.



630 AM UPDATE...
Have decided to increase precipitation chances again across the
center of the forecast area where current area of rain is expected
to move. Still occasional embedded lightning strikes noted with
this activity just now arriving in New Hampshire. Much of this
should be offshore by early afternoon.


5 AM UPDATE...
We are beginning to see the whites of its eyes on regional radar
as showers are expanding in coverage over upstate New York and
into Vermont. Have decided to increase precipitation chances based
on increased confidence in a more widespread rain event. Also
seeing occasional lightning strikes embedded in there, so a
mention of thunder as this moves through remains warranted.
Otherwise no significant changes needed.

ORIGINAL DISCUSSION...
Cold front to our west has already begun producing showers over
upstate New York. These will spread into New Hampshire before 8AM
and into Maine through the morning. Cannot rule out a stray
thunderstorm as well. After the front moves through today expect
winds to shift to the northwest eventually bringing in drier air.
The shift to northwest winds will cause downslope warming and
temperatures should warm into the upper 80s to low 90s later in
the afternoon after the rain moves away.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
Drier air moving in from the north will allow temperatures to fall
into the 50s for most of the area tonight. Saturday will not be
quite as warm without the downsloping winds but it should still be
above normal with widespread 80+ temperatures.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
The extended generally looks fairly quiet. The broad picture
initially favors troffing in the Wrn CONUS and conversely ridging
E. That supports a warmer than normal pattern for the first part
of the forecast period. Both the 26.00z GFS and ECMWF trend
towards the opposite pattern by the latter halves of their
respective runs. Lower heights across the Northeast would likely
spell cooler than normal...cloudy...and a chance of showers each
day. I am not ready to bite on that solution quiet yet...as model
guidance can tend to drill heights down in that region too
much...to fast. In addition there is model interaction with Invest
99 moving thru the Turks and Caicos that is influencing downstream
output.

In the medium range...a front is set to cross the area Sun night.
The parent s/wv trof shears off into Canada...and leaves forcing
rather meager across Nrn New England. There will be scattered
showers and perhaps a thunderstorm...though CAPE is limited and
mostly elevated...but overall QPF looks better to our W where
daytime heating will assist in sustaining convection.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
Short Term...Early morning fog at Lebanon and Whitefield should
dissipate as showers move in and the front passes by. Showers and
brief MVFR conditions possible at all sites, but most likely in
the western and southern areas through this morning. Should clear
to VFR areawide later this morning with a northwest flow
developing.

Long Term...VFR conditions are expected to prevail for much of the
extended. A front crossing the area Sun night will bring scattered
MVFR in SHRA and maybe a TSRA. Any heavier convection could bring
local IFR or lower conditions. Otherwise high pressure is in
control thru midweek...with patchy valley fog a possibility at
night.

&&

.MARINE...
Short Term...Southwest winds should remain below advisory levels
today with wave heights generally less than 5 FT. Cold front moves
offshore early this afternoon with a shift to northwest winds
behind it.

Long Term...Winds and seas look to remain below SCA thresholds
thru the weekend. Frontal passage on Monday and off shore winds
may allow seas outside of the bays to build to near 5 ft.

&&

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

&&

$$

NEAR TERM...Hanes
SHORT TERM...Kimble
LONG TERM...Legro



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.