Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Gray ME
348 am EST Sat Feb 13 2016

Synopsis...
an Arctic front will push through the region today as an inverted
trough of low pressure brings occasionally heavy snow to midcoast
Maine. The trough of low pressure will gradually shift off to the
southeast tonight as high pressure builds in from the west. High
pressure will continue to build in from the west Sunday and will
crest over the area Sunday night. High pressure will shift
offshore on Monday as a warm front approaches from the southwest.
Low pressure moving up the East Coast will push the warm front
north of the region on Tuesday. Low pressure will lift north into
Canada Tuesday night and a trailing cold front will swing through
the region. High pressure will build in from the west on Thursday
and will crest over the region on Friday.

&&

Near term /through today/...
Arctic front is gradually approaching from the west early this
morning bringing increasing clouds into New Hampshire and expect
this cloud cover to shift into western Maine through daybreak. Had
some rather impressive squalls ahead of the front earlier this
evening as it pushed into eastern New York but that activity has
diminished during the last few hours. Still looking for snow
showers and a few squalls as this boundary moves through western
zones this morning.

At the same time low level convergence zone setting up south of
midcoast Maine producing a very localized area of light to
moderate snow just offshore and occasionally pushing into the
Rockland area. Expect snow to become more widespread in the
midcoast area later this morning as an inverted trough becomes
more defined and the pressure gradient around this boundary
tightens.

Models still showing some diffs in where this trough axis sets up
but current buoy data currently show it just east or Rockland.
With this in mind will be sticking with current winter storm
warnings/advisories for the middle coast area. Good fluff factor and
enhanced onshore flow should produce 6 to 10 inches in the warning
area of Knox and coastal Waldo counties. Areas surrounding these
counties will see 3 to 6 inches through this evening. West of this
area...may see precipitation wrap back to the west as far as the capital
district where an inch or two of accumulation will be possible. In
addition increasing northwest winds behind the front will lead to
considerable blowing and drifting of snow later this afternoon.
Expect high temperatures to be reach by late morning before falling
through the afternoon. Highs will only range through the single
numbers north and teens south.

&&

Short term /tonight through 6 PM Sunday/...
snow will gradually taper off this evening in midcoast areas as
inverted trough shifts off to the southeast. Expect a fair amount
cloudiness to linger over the region overnight along with a few
snow showers as deep upper trough crosses the area. Surface high
building in from the west will bring partial clearing toward
Sunday morning. Strong northwest winds will continue overnight and
will produce dangerous wind chills. Wind chill warnings have been
hoisted for most interior sections of Maine and New Hampshire
with advisories for the coast. Looking for lows of 15 to 25 below
in the north and 5 to 15 below in the south.

Winds will gradually diminish on Sunday as high pressure builds in
from the west. Should see a mostly sunny day but despite the sun
temperatures will remain well below normal. Highs in the north
will only top at 5 below to 5 above and will range through the
single numbers across the south.

&&

Long term /Sunday night through Friday/...
Sunday night will be another very chilly night...although not
as chilly as as the previous night. Winds will be lighter with
high pressure cresting overhead. This will also allow skies to be
clear or mostly clear creating ideal conditions for radiational
cooling. Lows will dip into the negative teens f north to the
single negative digits f south and approaching zero along the
coast. We will likely need a Wind Chill Advisory for the north
country.

High pressure quickly moves offshore by Monday afternoon as a
warm front lifts north into the region. Parent low pressure will
be over Canada...however another low will form along the boundary
and travel NE deepening to about a 995mb cyclone as it moves
across northern New England. Precipitation will develop in
southern New Hampshire and spread north and east Monday night into Tuesday
with the heaviest quantitative precipitation forecast occurring during the day Tuesday.

Cold air in place will keep precipitation type as all snow Monday
into very early Tuesday morning. After midnight however we will
see a non-nocturnal curve as temperatures gradually increase. The
rain/snow line will move inland during the day Tuesday... with an
area of sleet and freezing rain possible at the interface as
warmer air continues to move in aloft on a strong 850mb low level jet of 75
kts. Most areas will switch to all rain by early afternoon except
for the mountains which will hang onto snow longer. Looking at the
quantitative precipitation forecast... this could be a significant snowfall event... especially
north of a line from Lebanon New Hampshire to the lakes region of Maine.
This would also depend on the fluff factor and at this point it
looks like this will be a more normal or wetter snow than we have
been having recently...indicating snow ratios between 1:10 and
1:13.

As the occluded system moves quickly northeast Tuesday night high
pressure moves in briefly making for a warm Wednesday. The cold
air associated with this system arrives Wednesday night bringing
scattered snow and possibly rain showers with it. This will knock
temperatures back closer to normal values for a time... at least
for southern sections. Northern sections will likely still be
below normals. High pressure crests overhead Friday as an area of
upper level ridging builds overhead. It is quickly pushed to the
east by multiple short waves... setting US up for another large
surface storm moving in from the Great Lakes region.

&&

Aviation /07z Saturday through Wednesday/...
short term...areas of IFR/LIFR ceilings and visibility in midcoast areas
today and MVFR /IFR ceilings and visibility in scattered snow showers
and squalls elsewhere. Becoming VFR after midnight. VFR on
Sunday.

Long term...mainly VFR Sun night through Monday with gusty northwest winds
diminishing Sun afternoon. Could see extended period of IFR or
lower in snow/fzra/ra Monday night into Tuesday night. Also winds will
again become gusty on Tuesday.

&&

Marine...
short term...continuing gales and heavy freezing spray warning for
the outer waters and sca's/heavy freezing spray warnings for the
bays through tonight.

Long term...winds and waves will drop below Small Craft Advisory criteria Sunday
afternoon with waves not increasing above 5 feet again until late
Monday night. Seas then increase to 10 or more feet by Tuesday.
Winds increase again by Tuesday with gales possible for the outer
waters.

&&

Gyx watches/warnings/advisories...
ME...wind chill warning from midnight tonight to 10 am EST Sunday
for mez012>014-018>022.
Wind chill warning from 7 PM this evening to 10 am EST Sunday
for mez007>009.
Winter Weather Advisory until midnight EST tonight for mez022-
026.
Wind Chill Advisory from midnight tonight to 10 am EST Sunday
for mez023>028.
Winter Storm Warning until midnight EST tonight for mez027-028.
New Hampshire...wind chill warning from midnight tonight to 10 am EST Sunday
for nhz004>013-015.
Wind chill warning from 7 PM this evening to 10 am EST Sunday
for nhz001>003.
Wind Chill Advisory from midnight tonight to 10 am EST Sunday
for nhz014.
Marine...heavy freezing spray warning from 7 PM this evening to noon
EST Sunday for anz150>154.
Small Craft Advisory from noon today to noon EST Sunday for
anz151-153.
Gale Warning from 4 PM this afternoon to noon EST Sunday for
anz150-152-154.

&&

$$

Sinsabaugh/Hanes

National Weather Service Glossary of Abbreviations