Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Caribou ME
1123 am EDT Thursday Aug 21 2014
high pressure will slowly build down across the area through the
Near term /through tonight/...
11:20 am update...made some minor modifications to cloud cover.
Also, added isolated showers to downeast areas this afternoon
where some of our mesoscale models are producing some showers
Previous discussion...high pressure will slowly build south
across the forecast area today and tonight. Meanwhile, weak upper
low pressure will slide southward out of Ontario into western New
York. This latter feature, along with weak southeast flow bringing
in a bit of additional, will allow for slight chance/low chances
of afternoon showers over central/western portions of our region.
Cape looks to be fairly meager due to a layer of warm air aloft,
but can't rule out perhaps a rumble of thunder or two. Much of the
short-range guidance indicates isolated showers will linger over
western/northern Maine through tonight. Temperatures will be
seasonable, with highs in the middle 70s to around 80 and lows in the
Short term /Friday through Saturday/...
a weak, and further weakening, upper level low will slide east
across New England and into the Gulf of Maine on Friday. Not
enough moisture or dynamics for much...just partly to mostly
cloudy skies with a slight chance of showers for most areas,
except a chance of showers over the western edge of our area
around Moosehead Lake.
High pressure then builds in from the north Friday night and
positions itself over New England for the weekend. Expect a dry
weekend with mostly clear skies.
Long term /Saturday night through Wednesday/...
warm late Summer weather will be the big story for Sunday into the
middle of next week. Upper level high pressure on Sunday will
gradually give way to westerly flow toward the middle of the week,
with perhaps somewhat increased afternoon/evening thunderstorm
chances around Wednesday, but still likely dry Sunday through
Temperatures may reach 80 on Sunday for a few places, with more
widespread low to middle 80s Monday through Wednesday, except cooler
70s near the coast. Went closer to the consensus of raw model
output over MOS guidance for highs, as 925 mb and 850 mb
temperatures justify going warmer than MOS, which trends toward
climatology in the extended anyway.
Models are in good agreement through Tuesday, but begin to have
issues around Wednesday as to whether we get a cold frontal
passage from the northwest Wednesday or Thursday, or stay in the
warm west/southwest flow for a bit longer.
Aviation /15z Thursday through Monday/...
near term: VFR conditions expected over the next 24 hours. Only
exception is localized MVFR/possible IFR in fog during the early
Short term: generally VFR Friday through early next week. One
exception is a possible period of MVFR ceilings early Friday
near term: high pressure will keep quiescent conditions on the
waters today and tonight. No headlines are anticipated.
Short term: winds and seas easily stay below small craft levels
Friday through early next week.