Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Gray ME
920 am EST Tuesday Dec 10 2013
low pressure will track to our south along a stalled frontal
boundary today. An Arctic cold front will approach from the west
tonight and will drop south through the region on Wednesday. A
weak ridge of high pressure will build in from the west Wednesday
night and Thursday. A cold front will approach from the northwest
Thursday night and will drop south through the region on Friday.
High pressure will build in from the north Friday night. A broad
area of low pressure will move northeast out of the Gulf of Mexico
on Saturday and will track northeast off the New England coast on
Near term /until 5 PM this afternoon/...
910 am...based on the 14z mesonet and the 12z kgyx radiosonde observation I adjusted
1st period temperatures up several degrees for the update. Mostly
cloudy as a surface low passes well south and east. As per GOES imagery...the
area will remain on the northern periphery of the cloud shield from
this system with southeast sections of the forecast area brushed
by a few snow showers or flurries.
650 am update...no significant changes to the current forecast.
Just a few minor adjustments based on latest trends in observational
A southern stream short wave trough will move across the Ohio
Valley early this morning and off the southern New England coast
this afternoon. The associated forcing for ascent with this
feature will graze our southern zones today.
Most model guidance is in good agreement with pushing a band of
snow across southern New England today...and this should graze our
southern zones with a little light snow late this morning through
early afternoon. Confidence in the northern extent of the light
snow shield is a little uncertain...but moisture and forcing
should be sufficient for likely probability of precipitation on our southern County Warning Area
border...with a rapid drop-off toward central New Hampshire and
north of York County Maine.
A dusting to 1 inch of snowfall will be possible in the likely pop
area. Otherwise...wouldn/T be surprised to see a period of very
light snow or flurries a little further north as the northern
stream short wave approaches later in the day.
The high temperature forecast was based on a blend of the
Short term /5 PM this afternoon through 6 PM Wednesday/...
dry weather is expected tonight aside from some upslope snow
showers in the mountains as we will be in an area of slight short
An Arctic front will approach the region on Wednesday. This will
allow for increasing chances of snow showers in the mountains as
the day progresses...with a few squalls possible later in the day
with the front. A few of these squalls may make it to the coast
toward Wednesday evening.
Long term /Wednesday night through Monday/...
Arctic front will push south of the region Wednesday night followed
by a weak ridge of high pressure. A few squalls may accompany the
front. Some of the coldest air of the season will filter in
behind this boundary overnight. With clearing skies and relatively
light winds will see temperatures plummet by Thursday morning with lows
of 5 below to 5 above in the north and many areas in the south
dipping into the single numbers.
Will see a mix of sun and clouds on Thursday as high pressure crests
over the region. Despite the sun will see high temperatures well below
normal with highs mostly in the single numbers north and in the
teens to near 20 south.
Weak low pressure tracking east through southern Canada will swing
another cold front toward the region Thursday night. Expect
thickening clouds and a chance of snow showers in western zones
toward daybreak. Will be another very cold night with lows similar
to Wednesday night.
Low pressure will pass through northern Maine on Friday swinging a
trailing cold front into the region. Will see a mostly cloudy day
with occasional snow showers but expect any precipitation to be light and
spotty with this moisture starved system. Will see highs edging
back toward normal with readings in the teens north and 20s south.
Cold front will stall out across southern New England Friday evening
keeping a fair amount of cloudiness in place especially in southern
Low pressure lifting northeast out of the Gulf on Saturday will set
up a broad area of light over-running precipitation which will shift into
the northeast during the day. May see several inches of accumulation
across southern New Hampshire by Saturday evening with lighter
amounts to the north and east.
Low pressure will become better organized off the Jersey coast
Saturday night and will intensify as it passes just off Cape Cod on
Sunday morning. Models coming into line with the track with the GFS
playing catchup to the European model (ecmwf) with some timing diffs remaining. Both
models bring this system close enough to the coast to produce a mix
in southern and coastal areas at some point late Saturday night and
Sunday. At this point appears the remainder of the forecast area
will see an all snow event with the potential for warning criteria
snowfall amounts. Stay tuned.
Aviation /14z Tuesday through Saturday/...
short term...mainly VFR conditions today. The exception will be
across southern New Hampshire and southernmost ME where a band of light
snowfall may allow for a few hours of MVFR conditions.
Otherwise...mainly VFR tonight and Wednesday outside of the
Long term...VFR Wednesday night and Thursday. Areas of MVFR/IFR
ceilings/visibility in the mountains Thursday night and Friday. IFR/LIFR
ceiling/visibility developing on Saturday.
short term...Small Craft Advisory for the ocean waters mainly for seas through
early this afternoon. Another Small Craft Advisory will likely be necessary for all
waters tonight through Wednesday.
Long term...sca/S likely through much of the period from Wednesday night
Marine...Small Craft Advisory until 2 PM EST this afternoon for anz150-