Scientific Forecaster Discussion

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Area forecast discussion 
National Weather Service Caribou ME
703 am EDT Friday Apr 18 2014

Synopsis...
cold high pressure will move east into the Maritimes today. A
trough of low press will approach the region tonight and move east
across the area Saturday. High pressure will build into the region on
Sunday.

&&

Near term /through tonight/...
700 am update: adjusted the sky and temperatures to match the
latest conditions and what satellite was indicating. High clouds
will pull out later this morning west/weak warm air advection aloft.

Previous discussion...
concerns this term are continued flood threat and possible snow
later tonight into Saturday morning.

Ice was moving down the St. John river through Madawaska into Van
Buren. The river appears to wide open north of Madawaska all the
way through Fort Kent back to St. Francis. Flood Watch remains up
and authorities are monitoring the situation. See hydrology
section below for more details.

06z surface analysis showed high pressure moving into the Maritimes. A
frontal boundary is forecast to approach the region later today
and then move into the region tonight with precipitation possible.
Before that happens, the region should see increasing clouds today
but moderating temperatures with readings by later today hitting
upper 40s and possibly lower 50s. Decided to stay pretty close to
the daycrew's thinking at this time west/this setup. Winds will be no higher
10 miles per hour which will aid in some melting of the remaining snowpack
especially across the north and west.

For tonight, clouds will thicken as a frontal boundary approaches
from Quebec. Temperatures will fall back as the column moistens.
Moderate soundings support evaporative cooling at the start of the
precipitation leading to more cooling in the blyr. Confidence is
high enough the the precipitation will fall in the form of snow
especially across the northern and western areas and right near
the Maine-Canadian border. There appears to be a middle level jetlet
of 30 kts streaming through the northern 1/2 of the region by
early Saturday morning enhancing precipitation for a time. Quantitative precipitation forecast
amounts are forecast to be no higher than 0.10" and using a
10-12:1 ratio this leads to snowfall amounts of 0.5 to 1.0 and
mainly across the far northern and western areas. Temperatures
will drop back below 32f across the northern 1/2 of the County Warning Area west/low
to middle 30s central and downeast.

&&

Short term /Saturday through Sunday/...
a shortwave trough will swing through northern Maine on
Saturday...bringing a chance of showers to The Crown of the state.
Weak surface high pressure builds in Saturday night and Sunday.
Temperatures will be below normal on Saturday and near normal on
Sunday.

&&

Long term /Sunday night through Thursday/...
high pressure aloft along the East Coast will result in a warm
Spring day on Monday. The rest of the week looks unsettled with a
deepening shortwave trough closing off in the vicinity of the New
England coast by middle week. The 00z GFS is closer to the coast and
deeper than the 00z European model (ecmwf). Both solutions are wet with heavier
quantitative precipitation forecast totals with the GFS. This scenario will need to be watched with
river levels still high after the ice break up.

&&

Aviation /12z Friday through Tuesday/...
near term: looks like VFR into tonight. There is a concern
for MVFR for kfve after 06z.

Short term: MVFR ceilings will be possible on Saturday in showers across
the northern taf sites /kfve kcar kpqi khul/
&&

Marine...
near term: no headlines. A swell continues at this time and it looks like
it will build gradually later today into tonight but wave heights
are forecast to remain below Small Craft Advisory levels. Winds will 10-15 kts at
best into tonight.

Short term: no headlines are forecast during this time period.

&&

Hydrology...
coordinated with local law enforcement officials and Aroostook
Ema and decided to cancel the Flood Watch as river levels are
receding and ice has flushed out of the St. John river.

The Mattawamkeag River has hit record flood stage west/the latest
reading of 16.10 feet and now crested. The Mattawamkeag River will
most likely remain above flood stage right into the Easter
weekend. The Penobscot, Piscataquis, and Aroostook rivers are
running high but are receding west/conditions improving.

&&

Car watches/warnings/advisories...
ME...none.
Marine...none.

&&

$$
Near term...Hewitt
short term...okulski
long term...okulski
aviation...Hewitt/okulski
marine...Hewitt/okulski
hydrology...Hewitt