Area Forecast Discussion
Issued by NWS Caribou, ME-- Highlight Changed Discussion --
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FXUS61 KCAR 241154
Area Forecast Discussion
National Weather Service Caribou ME
754 AM EDT TUE MAY 24 2016
Low pressure will lift across the region later today through
tonight. A cold front will cross the region Wednesday. High
pressure will build across the region Thursday.
.NEAR TERM /THROUGH TONIGHT/...
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Have included patchy fog early this morning across much of the
forecast area, with the exception of northwest areas. Have also
updated to adjust for cloud cover and current conditions.
Surface/upper level low pressure will lift north toward the
region today, then cross the forecast area tonight. Mostly/partly
sunny skies are expected across northern areas this morning, with
increasing clouds this afternoon. Isolated showers could begin to
approach northern areas late this afternoon. Generally expect
mostly cloudy skies across central/Downeast areas today, with
scattered showers mainly this afternoon. A cold front will also
approach northern Maine later tonight. Expect mostly cloudy skies
along with scattered showers across the forecast area tonight. The
warmest temperatures today will occur across northern areas, where
the most sun will occur, with upper 70s to around 80. The coolest
temperatures will occur Downeast, with the most extensive cloud
cover, with upper 60s to around 70 interior Downeast and mid 60s
along the Downeast coast. Low temperatures tonight will generally
range from the lower to mid 50s north, to around 50 to the lower
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.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
Wednesday morning a rapidly weakening 500mb shortwave will depart
the coastal Maine, with limited sensible weather, maybe a stray
shower across downeast. The bigger weather maker for the day will
be a surface cold front and 500mb shortwave trough from Quebec
province. There will be a quick low-level moisture flux with
surface dewpoints reaching near 60. This will have aid MUCAPE
values above 1000 J/KG, especially across eastern Maine Wednesday
afternoon. The GFS/NAM/SREF all show a descent CAPE axis during
the afternoon. This will be our best chance to see some convection
in quite some time. Right now I kept slight chance of thunder in
the forecast, but could see the potential for increasing this to
chance if guidance continues to trend up on CAPE values today. QPF
amounts will generally be less than .25", but could be locally
higher with PWAT values rising above 1.25". Front quickly pushes
off the coast Wednesday night.
Thursday looks to be a nice day with shortwave ridging and drier
air from Canada advecting in all day on NW flow. Moisture will
quickly stream back into the region on Thursday night as a warm
front pushes into the area. Moist southerly onshore flow will
bring in a low stratus deck. Isentropic lift will allow showers to
break out especially after midnight.
.LONG TERM /FRIDAY THROUGH MONDAY/...
Friday warm front will still be draped across the state with
moist southerly flow all day. Confidence is high that it will be a
mostly cloudy day with showers. Isentropic lift could be focused
across the County, enhancing rainfall across Northern Maine, in
addition to favorable upslope enhancement across the Central
Highlands. Overall doesn`t look to be the best day, but it will be
a warm airmass which will keep highs in the 60s, even under the
cloudy skies. We will remain in the warm sector through Friday
night with the possibility of some drizzle and low stratus.
The weekend currently looks to be 50/50 with Saturday looking to
be cloudy and rainy as a back door cold front approaches the
region from Northern Quebec. Both the GFS/ECWMF camps have this
wave, so confidence is moderate that Saturday could be a rainy
day. The good news is that guidance has the front pushing to the
south quickly Saturday night with potential clearing and dry
Canadian high pressure building over the region on Sunday. Dry
weather looks likely into Monday. Kept mention of thunder out for
the long-term with no strong signals supporting convection at this
time. Above average temperatures will continue for this period.
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --NEAR TERM: Generally expect VFR conditions across northern and
central areas today. However, variable conditions from MVFR to
LIFR are possible early this morning with patchy fog. Conditions
are then expected to lower to MVFR/IFR levels across northern and
central areas tonight. MVFR to LIFR conditions are expected
Downeast this morning, with generally MVFR conditions this
afternoon. MVFR to LIFR conditions are then expected Downeast
SHORT TERM: Biggest potential impact to aviation operations in
the short-term are thunderstorms during the afternoon on
Wednesday. Right now looks like the highest probability is across
the County TAF terminals with about a 40% chance for vicinity
storms. Lower chances are expected at KBGR/KBHB. Storms will
quickly exit Wednesday evening with high pressure on Thursday.
MVFR to IFR conditions are expected Friday into Saturday.
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NEAR TERM: Winds/seas are expected to remain below Small Craft
Advisory levels today through tonight. Visibilities will be
reduced in patchy fog and scattered showers today through
SHORT TERM: A cold front will push across the coastal waters
late Wednesday afternoon and early evening. An isolated
thunderstorm could be possible across the waters. Clearing is
expected by midnight with surface high pressure over the waters on
Thursday bringing offshore NW flow. SCA not anticipated at this