Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Caribou ME
1220 PM EDT Tuesday Mar 31 2015
a cold front will cross the region this morning. High pressure
will build across the area tonight and Wednesday. A warm front
will lift north across the area Thursday into Thursday night. A
cold front will cross the region Friday.
Near term /through tonight/...
1215 PM update... 12z kcar radiosonde observation showed very moist atmosphere
through about 600 mb. Visible Sat shows mainly cloudy skies across
northern and central areas and partly to mostly cloudy down east.
Expect mainly cloudy skies across the north today with just an
isolated rain/snow shower. Across central and down east expect
partly to mostly cloudy skies. High temperatures today will range
from the upper 30s to near 40 north and low to middle 40s down east.
Just minor tweaks to going forecast mainly to probability of precipitation and sky.
an upper level trough and surface cold front will cross the region
this morning. High pressure will then begin to build toward the
region later today through tonight. Expect mostly cloudy skies
along with scattered to isolated snow showers across the forecast
area this morning with any snow accumulations less than an inch.
Cloud cover will then decrease this afternoon. Skies will be
partly cloudy across northern areas this evening...with mostly
clear skies overnight. Mostly clear skies are expected downeast
tonight. High temperatures today will range from the middle 30s to
around 40 north...to the lower 40s downeast. Low temperatures
tonight will range from around 10 to 15 north...to the upper teens
to lower 20s downeast.
Short term /Wednesday through Thursday/...
the models are in good agreement through the period. A low will
track across the southern Gulf of Maine...a low will be exiting to
the NE into the Canadian Maritimes. Higher pressure will build
across the region and will dominate the weather through the early
portions of the period. A warm front will move into SW Maine Thursday
morning as the high pressure builds to the east. The warm fnt will
move into ctnrl Maine by afternoon. By the end of the period the
warm front will be over the Maine/New Brunswick border.
Loaded a blend of the NAM/Gem/GFS/ECMWF for hrly
T/dp/wnds/sky/pop grids...loaded a blend of GFS/European model (ecmwf) for quantitative precipitation forecast.
Added 15 percent to winds for gusts over land...35 percent over
coastal waters. Added nawave 4 for seas.
Long term /Thursday night through Monday/...
the models remain in good agreement at the start of the long
term. A warm front will be extended along the Maine/New Brunswick
border...its associated low will be over southern James Bay. By Friday
morning the GFS and European model (ecmwf) move the system east of Maine...with the
cold front extend SW from eastern New Brunswick along the coast of
Maine. Both models show a secondary low along the front over PA.
The cold front will remain over the Gulf of Maine through Sat
morning...when the secondary low move into the Gulf of Maine. The GFS
to the east of Cape Cod...the European model (ecmwf) north of Cape Cod. The
circulation around the low will bring the precipitation band back across
central Maine. A ridge of higher pressure will extend north from the
central US to northern Quebec. A new low moves southeast into the northern Great
Lakes. Sat evening the low in the Gulf of Maine moves east of Nova
Scotia...the ridge moves over Maine the new low moves to southwestern
Quebec. Early Sat morning the new low moves to northwestern Maine with a
weak boundary extending south to Cape Cod. The GFS and European model (ecmwf)
differ on speed of movement of this low. The GFS moves it to eastern
Maine Sun morning...then east into the central Gulf of St Lawrence. The
European model (ecmwf) has the low over southeast Quebec...by sun evening over eastern New
Brunswick. Higher pressure will ridge across the area for Monday
as a new system moves east across the central US.
Loaded the superblend through the period. Added 15 percent to winds
for gusts over land 35 percent over coastal waters. Loaded nawave
4 for seas.
Aviation /18z Tuesday through Sunday/...
near term: occasional MVFR conditions will occur across northern
areas this morning...with occasional MVFR conditions possible
downeast. Conditions will improve to VFR levels across the entire
forecast area this afternoon. VFR conditions will occur across the
forecast area tonight.
Short term: VFR conditions all sites Wednesday...higher clouds will move
across the area Wednesday night as a warm front approaches from the west.
By middle day Thursday MVFR conditions in scattered light snow...becoming MVFR
with periods of IFR in snow showers as the cold front approaches.
Temperatures will warm over night Thursday night with precipitation changing
to rain showers on Friday. MVFR/IFR conditions are expected Saturday.
near term: a Small Craft Advisory is in effect for the waters
through this evening. Marginal Small Craft Advisory conditions
could then persist tonight. Visibilities could locally be reduced
in any snow/rain showers this morning.
Short term: winds and seas below Small Craft Advisory Wednesday through early Friday morning.
An Small Craft Advisory may be required early Friday morning through early Sat morning as a
low moves through the Gulf of Maine.
Marine...Small Craft Advisory until 7 PM EDT this evening for