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Area forecast discussion 
National Weather Service Caribou ME
1208 am EST Monday Nov 24 2014

strong low pressure will move into the Great Lakes overnight then
northeast into Quebec province Monday. A cold front will cross the
region Monday night...with a second cold front crossing the region


Near term /through today/...
1205 am update...only significant change with this update was to
add some patchy fog for downeast/southern region of our forecast
area. Have noted that Bar Harbor is reporting 4 sm visibility, and
temperatures are approaching dewpoints elsewhere in the area. Otherwise,
only other adjustments were to temperatures to match current surface
observations. No other changes needed.

A strong southerly flow will develop overnight between low
pressure over the Great Lakes and strong high pressure over the
Atlantic. This will result in over-running precipitation
developing over the southern portion of the forecast area then
spreading northward during the morning on Monday. Temperatures
aloft and at the surface should be warm enough for liquid
precipitation. For probability of and quantitative precipitation forecast will use model
consensus approach and blend the NAM...GFS and European model (ecmwf). For
temperature and dewpoint have used the raw blend to better handle
the transition to a warmer air mass.


Short term /tonight through Wednesday/...
low pressure will track northwest of Maine Monday night drawing a
cold front across the region. A steadier rain will move east of
the region during the evening...with decreasing shower chances
overnight. A secondary cold front/trough will cross the region
Tuesday with partly/mostly cloudy skies along with a slight chance
of showers across the north and mountains...with partly cloudy
skies across central and downeast areas. High pressure will cross
the region Tuesday night with partly/mostly cloudy skies north and
partly cloudy skies across the remainder of the forecast area.
High pressure retreats to the northeast Wednesday while low
pressure intensifies along the middle Atlantic coast. Moisture will
expand north in advance of the low later Wednesday. Cloud cover
will increase across northern areas Wednesday. Cloud cover will
increase across central and downeast areas early Wednesday. A
rain/snow mix will then expand northward across central and
downeast areas through the afternoon. Temperatures will be at
above normal levels Tuesday...with near normal level temperatures


Long term /Wednesday night through Sunday/...
coastal low moving approaching from East Coast at start of
period. Models still show a considerable spread of solutions with
this system. 12z GFS shows a progressive low already entering
Canadian Maritimes by Thursday morning...with a much deeper and
western tracking system in the European model (ecmwf) model. Still feel European model (ecmwf) may be
overdone...but with a peak travel Holiday opted to use a blend
with more Gravity given to GFS solution. Raised probability of precipitation to
categorical over downeast to northeastern regions of the forecast
area...tapering to likely over the far northwest. With rapid
progression of system expect transition to snow showers by
Thursday afternoon with only scattered snow showers lingering across
the north though Friday. Next frontal system approaches from Great
Lakes by middle-day Saturday with weak overrunning of warm front by
late Saturday...especially western zones. Cold front will rapidly
swing across region on Sunday with widespread chnce of snow
showers and even colder Arctic air by the end of the period.


Aviation /05z Monday through Friday/...
near term: expect VFR conditions this evening then MVFR/IFR after
midnight through the day Monday.

Long term: MVFR/IFR conditions are expected across the entire
region early Monday night. Occasional MVFR conditions will remain
possible across northern areas later Monday night with VFR
conditions developing downeast. Occasional MVFR conditions could
occur across the north and mountains Tuesday. Otherwise...generally
VFR conditions are expected across the region Tuesday through
early Wednesday. Conditions will lower to MVFR/IFR levels across
central and downeast areas later Wednesday. MVFR to LIFR
conditions are expected across the entire region Wednesday night
through Thursday. Occasional MVFR conditions are then possible
across the region Thursday night into Friday.


near term: for sustained winds will use the nam12. Will issue
gale and start gale at 1500z and continue into the evening. Winds
may decrease somewhat later in the day as warm advection across
the waters stabilizes the boundary layer. Have remove Small Craft Advisory with
issuance of gale. For waves: with light wind conditions across
local waters the primary wave system is now long period southerly
wave group 7-8 feet/9 seconds. This wave system has been running
around 2 feet higher than the wave watch iii model so after
initializing with the wna/4 have adjusted wave heights higher to
better fit observations. This fetch should fall below Small Craft Advisory this
evening as this wave system subsides... based on wave watch iii
guidance. A significant new fetch will develop this evening from
the Gulf of Maine southward as wind forcing increases. Expect
waves to build to around 14 feet/10 seconds by early evening

Short term: a Gale Warning will remain in effect for the waters
Monday night. Small Craft Advisory conditions are then expected
Tuesday through Wednesday. Visibilities will be reduced in rain
early Monday night...then again Wednesday afternoon.


Car watches/warnings/advisories...
Marine...Gale Warning from 10 am this morning to 4 am EST Tuesday for



Near term...Hastings/mignone
short term...Norcross
long term...pjr

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