Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Caribou ME
935 PM EDT Wednesday Mar 12 2014
strong low pressure will track from southern New England to
western Nova Scotia tonight then continue northeast across the
Maritimes on Thursday. High pressure will build toward the area
later Thursday night.
Near term /through Thursday/...
935 PM update...low pressure is near kbdr at 01z and based on the 3
and 6 hour pressure falls it should end up near the southern tip of
Nova Scotia by 12z Thursday. Snow continues to fall in all areas north
of Bangor with widespread amounts of 5 to 8 inches for interior
downeast into central Maine. So far Lincoln has been the Winner
with 10 inches. The big challenge is along the coast where mostly
rain has been falling this evening. Have lowered the totals along
the coast and think that with the next update we might be able to
cancel the warnings and/or transition to advisories in coastal
Hancock and coastal Washington counties. Freezing rain and sleet
are still a concern just inland so did not want to be too quick to
drop the warnings with several more hours of heavy precipitation
to fall across the area. The Bangor area has mixed with some sleet
and this shows up well in the new dual-pol products such as the
a strong area of low pressure centered over southern New England
this evening remains on track to bring heavy snowfall across much
of the region tonight. Thicknesses continue to show a significant
warm layer moving inland from the coast just above 5000 feet in
elevation. This will likely result in a large band of freezing
precipitation across extreme southern Penobscot...Hancock and
central Washington counties overnight. A quarter to a third of an
inch of freezing rain is possible along a narrow band from just
south of Bangor east across Central Hancock and south central
Washington County. Across central and northern parts of our region
heavy snow and blowing snow can be expected overnight. The
heaviest snow will be over by sunrise Thursday. However...the
upper level trough will bring light snow throughout the day
Thursday. Strong northeast to north winds will result in
significant blowing and drifting tonight through Thursday.
Short term /Thursday night through Saturday/...
low pressure exits across the Maritimes early Thursday
night...with high pressure building toward the region late. Snow
will taper to snow snow showers before ending early Thursday
night. Gusty winds winds will also produce areas of blowing snow
early Thursday night. Cloud cover will then decrease later
Thursday night with building high pressure. High pressure crosses
the region early Friday. Low pressure moving east from the Great
Lakes will begin to draw a warm front toward the region later
Friday. Cloud cover will increase Friday afternoon in advance of
the warm front. Snow chances will also begin to increase later
Friday afternoon...mostly across northwest portions of the
forecast area. The low will approach northern Maine later Friday
night. Isentropic lift will help produce snow across the region
Friday night. Expect the steadiest snow Friday night will occur
across northern areas nearer the track of the approaching low.
Could have several inches of snow across northern areas Friday
night...with snow accumulations downeast generally an inch or
less. The low crosses northern Maine Saturday with a cold front
starting to cross the region during the afternoon. Expect snow
showers across northern areas Saturday morning...with mixed
rain/snow showers during the afternoon. Across downeast areas
expect mixed rain/snow showers Saturday morning...with a chance of
rain showers during the afternoon. Wind chill advisories could be
needed across northern areas later Thursday night. Temperatures
will be at below normal levels Friday. Temperatures will then be
slow to fall Friday night with south winds and cloud cover...with
temperatures starting to slowly rise later Friday night. Above
normal level temperatures are expected Saturday in advance of the
Long term /Saturday night through Wednesday/...
at the start of the period the models are in good agreement. A
low pressure system will be exiting into the Canadian
Maritimes...a ridge of higher pressure builds into western Maine.
There will be a new low pressure system over the northern Great Lakes.
Friday morning the high pressure ridge crest over the area...the low
moves east into the central Great Lakes region with a supporting
short wave moving into Eastern Lake Superior a warm front extending
east into Vermont. The ridge builds east into the Maritimes. Friday evening
the surface low and short wave will become stacked over the eastern Great
Lakes...with a warm front extended east across Maine. Sat morning the
low moves east into northwest Maine. A secondary short wave digs south
into the central Great Lakes region. Sat evening the low will move east
into New Brunswick...a trough of lower pressure will extend SW
across Maine toward the southern Great Lakes. Sun morning the secondary
short wave moves into southern Quebec...the surface trough remains across
Maine. Sun evening the short wave moves into western New
Brunswick...higher pressure builds into western Maine. The European model (ecmwf) and
Gem move the short wave through much quicker than the GFS...and
shows the ridge building across the region earlier. A low pressure
system along the coast of Louisiana Sun morning will deepen and move
to the coast of North Carolina by Monday morning...then north into the
North Atlantic Monday evening. The GFS keeps this system well south and
east of our area...the Gem and European model (ecmwf) bring this low closer in. The
European model (ecmwf) keeps it south of Nova Scotia...which would only affect the
downeast coast and coastal waters. The Gem brings it closer to
Nova Scotia... affecting weather conditions into central ME. By Tuesday morning the
low will be well east of the area...and higher pressure will build
across Maine. A low pressure system moving across the Great Lakes
early Wednesday (across northern Great Lakes GFS...southern Great Lakes ecmwf)
will move into Maine Wednesday morning according to the GFS...coastal Maine
Wednesday evening European model (ecmwf). Both models move the low east of our area by the
end of the period.
Loaded superblend through the period...added 15 percent to the
winds for gusts over land 25 percent over the coastal waters.
Aviation /01z Thursday through Monday/...
near term: IFR/LIFR conditions are expected tonight through Thursday.
Expect heavy snow north and icing downeast tonight. Wind...light
snow and blowing snow will prevail on Thursday.
Short term: MVFR/IFR conditions will occur early Thursday
night...then improve to VFR levels. VFR conditions will persist
much of Friday...with MVFR conditions starting to develop later in
the afternoon. Conditions will lower to MVFR to LIFR levels Friday
night. MVFR/IFR conditions are expected early Saturday...with
occasional MVFR conditions still possible Saturday afternoon.
MVFR conditions will continue into early morning
Sunday...improving late in the day Sunday to VFR. VFR conditions
will prevail late Sunday through the end of the period.
near term: a Gale Warning is up for strong northeast winds tonight
and north winds on Thursday. Some light freezing spray is possible
Thursday as colder air pushes across the waters.
Short term: gale force winds are expected into the early morning
hours Friday. Small Craft Advisory conditions are then expected
into Friday. Conditions could briefly fall below Small Craft
Advisory levels later Friday. Small Craft Advisory conditions will
develop again Friday night and persist Saturday. Visibilities will
be reduced in snow early Thursday night...then again Friday night.
Mixed rain/snow showers early Saturday...will transition to rain
showers. Freezing spray is expected Thursday night into early
ME...Winter Storm Warning until 6 PM EDT Thursday for mez001>006-
Marine...Gale Warning until 2 am EDT Friday for anz050>052.