Area forecast discussion
National Weather Service Caribou ME
1002 am EDT sun may 19 2013
Synopsis...
high pressure will remain over the area today. The high will move
east this evening as a small wave of low pressure slides in from
central Canada. The low will cross the area early Monday morning
followed by high pressure later Monday through Tuesday.
&&
Near term /through tonight/...
update 0955 edt: have adjusted temperature and sky cover based on
observations.
A surface ridge covers the northern and western Maritimes and into
the Gulf of Maine early this morning. A very tricky sky forecast
as an area of status with ceilings around 2 k feet above ground level has developed
from about Houlton-Millinocket and points southeast across central
Penobscot County and much of Washington County. Outside of this
area of stratus most areas will start clear and frosty with some
increase in clouds late in the day across the western zones. The
ridge will slowly drift to the southeast through ton. A weak surface low and
frontal boundary will move into the County Warning Area ton with most of the
support in the middle/upper levels as shortwave energy and an area of
lift moves out of Canada and across the area. The models all have
an area of 1/2 inch of quantitative precipitation forecast across the western zones from 06-12z
Monday...and the GFS and NAM have bulls- eyes in excess of an inch
across the western mountains which looks overdone. The models do
still differ some on the timing and location of the heaviest qfp
late ton into early Monday morning. Confidence is high enough to
spread categorical probability of precipitation in from west late ton along with patchy
fog downeast where the flow off the water will result in some low
clouds. The clouds/rain will make for a much milder night than the
last several...with lows mostly in the 40s and no threat of frost.
&&
Short term /Monday through Tuesday/...
Monday will dawn with rain across the area as a small low dropping
in from central Canada pulls a surge of warm advection rain out
ahead of it. The low is fast moving and rain will quickly move
southeast and away during the middle morning Monday. Skies will
likely remain mostly cloudy through midday with stratocumulus
clouds. Skies will then becoming increasingly clear late in the
day and into the evening as high pressure and drier air press in
from the northwest. Canadian high pressure will bring a mostly
clear and cool night Monday night followed by a sunny to partly
cloudy day on Tuesday as the high builds over.
&&
Long term /Tuesday night through Saturday/...
Tuesday night will be clear and cool across the area with high
pressure in place. The high will likely bring a dry start to the
day on Wednesday. Our focus then turns to a large area of low
pressure in the upper Midwest. Forecast guidance has been very
ambivalent about whether this storm would make it into our area
with some guidance keeping the moisture to our south along a
frontal boundary and some guidance lifting the moisture into our
area. The key feature in guiding this system east seems to be a
large upper trough in eastern Canada. If this trough digs back to
the southwest it could capture and lift the plains storm east
northeast into our region. However...if the Canadian trough just
drops south into New England it would suppress the moisture to our
south keeping our area cool and dry. Currently the guidance is
indicating that enough of the Canadian trough will drop back
southwestward to pull some moisture and rain into our area later
Wednesday into Thursday. Eventually the trough digs down across
our region pushing the remaining moisture east and bringing a
return of drier and moderately cooler air late in the week.
&&
Aviation /14z Sunday through Thursday/...
near term: mostly MVFR at the terminals early this morning as a
fairly extensive area of stratus developed overnight. Conditions
are expected to improve the VFR by 14-15z...but patches of stratus
may linger near the coast into the afternoon. Conditions lowering
to IFR around 04z at kbgr and kbhb in low stratus tonight...and
after 08z at the northern terminals in stratus and rain.
Short term: IFR conditions in rain Monday morning will improve to
MVFR by midday Monday then VFR Monday afternoon. VFR conditions
are expected Tuesday into Wednesday morning. Conditions may lower
to MVFR or IFR late Wednesday into Thursday as clouds and rain
move in.
&&
Marine...
near term: a light wind regime today with the wind picking up
ton as the high drifts southeast of the area and weak low pressure
passes well northwest of the waters. Sustained wind of 15 to 20 knots
developing late ton with gusts to 25 knots. Will start a Small Craft Advisory at 08z
ton. Fog will likely develop late this evening and may limit the
visibility to under 1 nm at times tonight.
Short term: an Small Craft Advisory will be needed for wind gusts over 25 knots
Monday morning. Some fog may limit visibility early Monday. Winds
will diminish Monday afternoon and remain below Small Craft Advisory through
Tuesday. Winds may reach Small Craft Advisory again late Wednesday as low pressure
approaches again.
&&
Car watches/warnings/advisories...
ME...none.
Marine...Small Craft Advisory from 4 am to 2 PM EDT Monday for
anz050>052.
&&
$$
Near term...mignone
