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FXUS61 KCAR 201003

Area Forecast Discussion
National Weather Service Caribou ME
603 AM EDT Sun Aug 20 2017

High pressure will build to the south of the area today and
Monday. Low pressure will pass to the west of the region Tuesday
night and a cold front will cross the area Wednesday. High
pressure will build back toward the area at the end of the week.


6:03 AM Update...Low clouds and areas of fog cover much of the 
forecast area early this morning with some breaks showing up 
across central portions of the CWA. An area of showers is 
showing up on radar just southwest of the area and will move 
across Downeast Maine this morning. Additional showers will 
likely develop and move across northern areas later this morning
into early afternoon. The main update was to the PoPs for this 
morning to better account for the area of showers that will be 
moving across the Downeast Region. 

Previous discussion...
An occluded front crossing the region early this morning will 
push east. High pressure will build south of the region later 
today and tonight. A mid level trough axis will move into 
western Maine this morning and will flatten out as it shifts 
east of the area by this afternoon. The forecast area is 
blanketed by low stratus and areas of fog early this morning, 
although there are a few breaks in the clouds in central 
portions of the CWA. The low clouds will lift this morning as 
westerly flow develops. As the mid level trough crosses the area
the combination of the residual moisture, daytime heating, and 
lift will likely produce some more scattered showers later this 
morning into the first half of the afternoon, mainly across 
northern and eastern portions of the CWA. It should turn into a 
nice afternoon by late in the day with at least partial sunshine
and lowering humidity. There will be very steep lapse rates 
from 8-10C/KM below 800H which will lead to a gusty west wind 
that will gust to 20 to 30 mph at times from later this morning 
until shortly before sunset. Highs this afternoon will be about 
10 degrees (F) warmer than Saturday with highs ranging from the 
mid 70s in the Saint John Valley to the low 80s in the Greater 
Bangor Region. Tonight will be clear to p/cloudy, and as the 
atmosphere rapidly decouples toward sunset the wind will become 
light. The air mass aloft is quite mild and this will limit the 
potential cooling with lows mostly in the 50s.


Very warm and increasingly humid weather can be expected to
start the work week as an area of high pressure builds across to
our south. Temperatures at H925 warm to about +22C during Monday
across portions of the region with mostly sunny skies expected.
Highs will range from the low to mid 80s across much of the
region, which is several degrees above normal for this time of
year. A cold front will approach from the northwest Monday night
with partly to mostly cloudy skies across northern areas and 
the chance for late night showers. Across central and down east 
expect mainly clear to partly cloudy skies. Lows Monday night 
will be well above normal, with lows expected to generally range
from the low to mid 60s across the region. The front will stall
across far northern areas Tuesday as an area of low pressure 
tracks northeast across Quebec province. The combination of the 
stalled frontal boundary in the vicinity of northern Maine and 
low pressure to our northwest will result in increasing chances 
for showers and thunderstorms during Tuesday, especially across 
northern areas. An increasingly moist air mass is expected to be
in place with dew points in the low to mid 60s and precipitable 
water values expected to increase to greater than 1.50" which could
lead to the possibility of locally heavy rainfall later Tuesday
afternoon across northern areas, especially in any 
thunderstorms. Highs on Tuesday will again be above normal for 
this time of year, with highs expected to range from the mid to 
upper 70s north and low to mid 80s down east.


Low pressure will continue to track to our north Tuesday night
with a warm front lifting up across the region to our north. The
chance for showers and thunderstorms will continue overnight
Tuesday, as a warm and humid air mass remains in place across
the region ahead of an approaching cold front from the west. The
cold front is expected to cross northern areas Wednesday morning
and reach the down east coast later Wednesday afternoon. Expect
a continued chance for showers with the passage of the front. A
large area of high pressure will then begin to build east toward
the region Wednesday night through Saturday, with a much cooler
and drier air mass spreading across the region for mid week into
next weekend. With an upper trof remaining to our north couldn't
rule out an isolated shower across northern areas through late
week, otherwise expect mainly dry weather through the period
with temperatures expected to below normal by late week and 
into next weekend.


NEAR TERM: VLIFR to IFR ceilings early this morning will lift 
to VFR by 13z to 15Z. VFR expected from 15Z this morning through
12Z Monday morning.

SHORT TERM: VFR conditions can be expected Monday and Monday
night. Showers and thunderstorms can be expected Tuesday
afternoon, especially at the northern terminals, with the
potential for sub VFR conditions at times. Expect MVFR
conditions Tuesday night in showers and thunderstorms, along
with patchy fog. Showers can be expected into Wednesday with
mainly VFR expected. VFR expected on Thursday.


NEAR TERM: The wind and seas will remain below small craft advisory 
levels through tonight.  Areas of fog will produce poor visibility 
early this morning. 

SHORT TERM: Winds/seas are expected to remain below small craft
advisory levels Monday into Tuesday. Winds/seas may could
increase to small craft advisory levels by Tuesday night and
Wednesday. Visibility will likely be reduced to 1 to 3 nm
Tuesday night in showers and thunderstorms, along with patchy


ME...Beach Hazards Statement through this evening for MEZ029-030.



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