989
FXUS61 KCAR 290651
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
251 AM EDT Sat Jun 29 2024

.SYNOPSIS...
High pressure will slowly exit to the east today. A warm front
lifts to the north Saturday night, followed by a cold front
crossing the region from Sunday into Sunday night. High pressure
then builds through Wednesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
High clouds will thicken and lower throughout the day as a warm
front approaches from the west. These clouds will reduce surface
heating compared to yesterday. Highs will reach the lower 70s in
Aroostook County, but an onshore flow will limit highs to the
mid to upper 60s towards the coast. An usually powerful low
level jet arrives from the southwest in the afternoon with a
magnitude near 60 kt at 850mb. This will be mostly in northern
zones. While the thickening high clouds will dampen mixing
somewhat, gusts to 40 mph are still possible in the afternoon
from the south to southwest. Chances for precipitation will
increase by the mid to late afternoon as very dry air under H7
is finally overcome.

The LLJ continues moving over the area through the night, but
concerns shift from strong surface winds to anomalously high
moisture transport with the warm front. Precipitable water
values surge towards 2 inches Saturday night with a deep warm
cloud layer nearing 13 to 14k ft. Elevated instability increases
through the night as a low level thermal ridge builds into the
area. 850mb temps may reach up to 17C by later in the night. As
a result, will mention thunderstorms through the night with the
warm front. Heavy rain is also a threat. Expect generally less
than an inch, but amounts could be locally higher with embedded
convection.

The warm front will introduce very warm and humid air by late
night with dew points climbing into the mid to upper 60s by
early Sunday morning. This moisture will likely generate fog
under the frontal inversion later in the night into early
Sunday morning as winds decrease.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
A cold front will move through the region on Sunday, bringing
showers and strong thunderstorms to the area. For the morning,
rain showers from Saturday night will continue. SW winds will
continue to be breezy. The 925-850mb model temps show the
morning temps climbing into the 60s early. By the afternoon, the
cold front is expected to quickly move into the region by early
afternoon and progress into the Central Highlands by the middle
of the afternoon. The concern will be the rapidly increasing
instability ahead of the front. Upper air model soundings
indicate a corridor of high CAPE values >1000 J/kg from Central
Aroostook, through the Central Highlands, and into the Bangor
Region by the afternoon. This line of CAPE should progress from
the NW to SE. In addition with the high CAPE, is the high bulk
shear values of >40 kts that will help support stronger
updrafts, producing gusty winds and hail. Some of these storms
are expected to be severe. Confidence has increased with the
expansion of the Slight risk of severe thunderstorms by SPC.

By Sunday night, the front should exit over the waters. As high
pressure moves in, clouds should begin the clear and NW flow
should decrease. High pressure is expected to remain in the
areas through Monday and Monday night, keeping skies fairly
clear and temps near normal.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
High pressure remains in the area through much of next week,
making for inactive weather. The next systems is expected to
move into the region on Thursday in the form of a cold front.
Models are in better agreement with the track and of the front,
but still inconsistent with the timing. Decided to go with
chance showers. Thunderstorms are also possible, but did not
include with this update due to lower confidence in the cold
front timing. High pressure should return for the end of the
week. Temps should be on a warming trend with above normal
temps.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: VFR conditions today will give way to IFR cigs/vis in
rain this evening...and eventually to LIFR cigs/vis in fog and
drizzle by late tonight. Strong LLWS will commence late this
afternoon and continue all of Saturday night with southwest
winds in excess of 50 kt at FL020. Embedded thunderstorms are
also expected Saturday night.

SHORT TERM: Sun...MVFR/IFR, then becoming VFR afternoon. TSRA
expected. S to SW wind G20 to 25 kt, then becoming NW late.

Sun night...MVFR possible KBGR/KBHB early in lingering TSRA,
otherwise improving to VFR. NW winds 5-10 kts.

Mon through Wed...VFR. NNW winds 5-10 kts, then light and
variable Tue night. S winds 5-10 kts Wed.

&&

.MARINE...
NEAR TERM: In spite of the usual strong summer stability and
steep inversion, Saturday night winds will still be more than
sufficient to generate a Small Craft Advisory. In response to
winds gusting to 30 kt, seas will build to over 7 feet Saturday
night. In addition, fog and thunderstorms can be expected
Saturday night. Inexperienced mariners should avoid navigating
in these hazardous conditions Saturday night. The Small Craft
Advisory begins Saturday evening and continues through the
night.

SHORT TERM: SCA conditions are possible Sun through Sun night,
otherwise expect below SCA conditions the remainder of the
period. Visibility will be reduced to 1 to 3 NM in any showers
and thunderstorms on Sunday.

&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...Small Craft Advisory from 8 PM this evening to 2 AM EDT Monday
     for ANZ050>052.

&&

$$


Near Term...MCW
Short Term...LaFlash
Long Term...LaFlash
Aviation...MCW/LaFlash
Marine...MCW/LaFlash