Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Caribou ME
1213 am EST sun Mar 9 2014
high pressure builds tonight into Monday morning. Low pressure
approaches from Quebec Monday night and will cross the region
Tuesday. High pressure returns Tuesday night into Wednesday.&&
Near term /through today/...
update 0010l: clear skies across the forecast area at this time as Cold Ridge of high
pressure centered well west of the area builds ewrd... current forecast on track
west/ no changes warranted at this time.
955 PM update...high pressure across the Great Lakes will slowly
build toward the region tonight...and will crest the area in about
24 hours. Temperatures continue to slowly fall this evening with
cold air advection in the wake of a cold front that crossed the
County Warning Area earlier today. The 00z kcar radiosonde observation shows the cold advection well
with significant cooling noted at all levels in the past 24 hours.
A mainly clear sky is expected overnight with low temperatures in the
single digits across northern Maine and 10-15f for the Bangor area
and downeast coast. Only minor tweaks to the sky...temperatures & wind
based on the latest satellite pictures and observations.
a rapidly weakening cold front is crossing the southern half of
the forecast area at this time. There is no precipitation with the
front and cloud cover associated with the front is rapidly
breaking up. This will lead into a generally clear night for most
of the area. A weak secondary trough will cross later this evening
with a few clouds towards the Saint John valley. Cold air
advection will continue through the night and temperatures will
fall to low single digits north and low teens for Bangor and down
east. Winds will remain fairly steady through the night with some
gusts to 20 miles per hour at times through the evening. Sunday will start
sunny...but just enough h850-h925 appears to be available for
widespread cumulus and stratocumulus fields across the forecast
area. Highs will reach the low 20s in northern Aroostook and
increase southward to around 30f for Bangor and Brewer. These
clouds will dissolve late day as the ridge axis moves over the
region and the northerly flow ends.
Short term /Sunday night through Tuesday/...
a pair of clipper systems will affect the area for the short
range. The first disturbance dives south and east toward the
region Sunday night into early Monday but will weaken as it moves
into the high pressure ridge which will be slow to push east. For
this reason kept probability of precipitation limited to slight chance and low end chance
for some flurries for later Sunday night into early Monday. Expect
some sun by the afternoon as this system departs with seasonally
cold temperatures continuing. A stronger impulse moves through from northwest to southeast
later Monday night into early Tuesday bringing a better chance for
snow with the potential for a couple inches of accumulation. As
the low moves through this will bring some milder air in on SW
winds with highs Tuesday ranging from the low 30s north to the upper 30s
Long term /Tuesday night through Sunday/...
the forecast becomes more complex for the long range as attention
turns to a more significant storm developing over Texas and
Oklahoma. This storm will approach the area from the south and
west heading into Wednesday at the same time an Arctic front and
associated high pressure center pushes down from the north.
Exactly how these features all interact, which is still uncertain,
will determine the ultimate track, speed, and intensity of the low
and its impacts over the area. While the 12z deterministic
forecast guidance has shifted back to the north with this storm system,
there are still differences between the forecast models with
considerable spread amongst the ensemble model guidance. With this
update did raise probability of precipitation to low end likely downeast for Wednesday
night into Thursday but maintained chance probability of precipitation elsewhere. With a
track south and east of the area, any precipitation with this system
would most likely be snow across the majority of the region with
any mixing or chance to rain limited to the coast. A transient
area of high pressure with seasonably cold temperatures follows for the
tail end of the week with the next system, a weaker one,
potentially bringing some rain or snow showers by the beginning of
next weekend with milder temperatures.
Aviation /05z Sunday through Thursday/...
near term: VFR overnight. Pockets of MVFR developing by middle-late
morning Sunday as cumulus and stratocu develop...mainly to the north of
Short term: a period of MVFR/IFR will be possible Sunday
night into early Monday as a weak system moves through. Conditions
improve by late Monday with a second, stronger system moving
through late Monday night into the first part of Tuesday bringing
a better chance for MVFR/IFR due to low ceilings and reduced
visibilities in snow. This system departs by later Tuesday with
the potential for a coastal storm to affect especially the
southern sites with snow and wind by later Wednesday into Thursday
bringing the threat for IFR conditions.
near term: cold air advection over the waters will likely produce
some wind gusts to 25 kts overnight with seas building to around
6 feet. The wind will diminish and the seas subside during the day
Sunday as high pressure builds over the waters.
conditions will be tranquil on the seas for the first part of the
week and are expected to remain below Small Craft Advisory levels through this
period. A coastal storm will have a good chance of impacting the
area by later Wednesday into Thursday bringing the potential for
Small Craft Advisory conditions along with snow and rain.
Marine...Small Craft Advisory until 10 am EDT this morning for