Area Forecast Discussion
Issued by NWS Caribou, ME
FXUS61 KCAR 301641
Area Forecast Discussion
National Weather Service Caribou ME
1241 PM EDT MON MAY 30 2016
A warm front will cross the region today. A cold front will move
across the area tonight and will be followed by another cold front
during the day Tuesday. High pressure builds across the area
Wednesday into Thursday. Another weather system will cross
northern New England Friday.
.NEAR TERM /THROUGH TONIGHT/...
1235 PM update...The thoughts on today`s convection have not
changed since this morning. Please see the previous discussion
below. Satellite imagery shows breaks are starting to develop in
the cloud cover across western Maine. Many locations in Quebec
where the sun has been more abundant so far today are already in
the mid 70s with dewpoints in the lower to mid 60s. This air will
spread eastward into Maine through the afternoon. The only real
change that was made to the forecast was to extend the
thunderstorm coverage and enhanced wording a bit further east
since storms that develop over the North Woods will drift into
these locations. Otherwise, the forecast remains in good shape.
Previous discussion...The warm front is lifting across the state
this morning, and its associated band of showers will continue to
cross the region as well. Once this first batch of precipitation
moves through, our focus becomes the potential for convection this
afternoon, particularly in the North Woods down toward the
Moosehead region. There`s plenty of shear availble for organized
storms, with 0-6km Bulk Shear progged to be around 40 kt. The
question will be one of instability, which will depend heavily on
how much sunshine is able to break through the cloud cover. There
is clearing seen to our west on visible satellite, and with
dewpoints rising into the lower to mid 60s on the other side of
the front, would expect to see storms pop up by mid afternoon
where solar heating is able to take place. Have adjusted pops to
match current radar trends, but kept the mention of gusty winds
and small hail in the forecast. Any SBCAPE would be modest, maxing
out around 800 J/kg, but given the amount of shear, would not be
surprised to see a few strong to possibly severe storms develop
this afternoon, mainly in the far northwest. The latest SPC Day 1
outlook matches this thinking, keeping areas north and west of a
Houlton to Augusta line in a Marginal Risk.
A weak cold front will move across the region this evening but
the air mass is only slightly drier behind the front. There could
be a few lingering showers or isolated thunderstorms across
northern areas early this evening, otherwise expect partly to
mostly cloudy skies tonight along with patchy fog. Lows tonight
will remain on the mild side with temperatures generally in the
upper 50s to near 60 degrees.
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
An upper trough digging into central Quebec at 12Z Tuesday will move
across Maine Tuesday afternoon, and will push a cold front across
the region. This will produce a few showers and thunderstorms
Tuesday afternoon and evening. Drier air follows Tue night and
Wed as a sfc high builds into the region and crests over Maine
Wednesday afternoon. Temperatures Wed will be seasonable for the
start of June with highs in the mid to upper 60s in far northern
Maine to the lower 70s for interior Downeast.
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
The long term starts dry and pleasant, and becomes increasingly
unsettled as the weekend approaches. High pressure slowly moves
east of the area Thursday as low pressure and an upper trough
approach from the west. As the flow turns onshore Thu night into
Fri expect there will be some marine stratus that will be
advected north. As a weather system moves in from the west later
Thu night and Fri the threat of showers will be on the increase.
A positive PNS/Negative NAO pattern expected by next weekend with
strong western Conus ridging and a downstream trough across the
Great lakes and Northeast U.S. This will produce an unsettled
pattern with more clouds than sun next weekend, and the chance of
a few showers and thunderstorms. Temperatures will likely be
seasonable, but highly depended on the amount of cloud cover.
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
NEAR TERM: Widespread MVFR and IFR conditions can be expected
across the area this morning in low ceilings and patchy fog. LIFR
can be expected KBGR/KBHB early this morning in areas of fog.
Expect conditions to improve to improve to VFR this afternoon all
terminals, but marine stratus may hold at KBHB most of the day
with IFR conditions possible into the afternoon. An isolated tstm
cant be ruled out late this afternoon at the northern terminals,
but confidence is low so will not mention in the TAF yet.
Expect VFR/MVFR conditions tonight across the north and IFR in
developing fog/stratus at KBGR/KBHB.
SHORT TERM: mvfr with brief ifr in Scattered showers and
thunderstorms at the terminals Tuesday afternoon. VFR expected to
return to the terminals Tuesday night and continue into Thursday
evening. IFR ceilings may develop Thursday night or Friday morning
as the flow turns onshore and stratus develops, especially at the
NEAR TERM: Winds/seas will remain below small craft advisory
levels through tonight. Expect visibility to be reduced to 10 to
3nm in fog and showers through tonight.
SHORT TERM: The wind and seas are expected to remain below small craft
advisory levels for the most part Tuesday through Friday. The seas
on the coastal waters may approach 5 feet Tuesday. Areas of fog are
likely on the waters later Thursday night and Friday.