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Area forecast discussion
National Weather Service Caribou ME
1217 am EDT Thu Apr 27 2017

weakening low pressure off the New Jersey coast will slowly
drift northeastward tonight into early Thursday. A cold front
will cross the region Friday.


Near term /through today/...
1215 am update...
low clouds, light rain/drizzle, and areas of fog will continue
across the region overnight as moist southeast flow persists
overnight. Raised overnight lows as temperatures have already
into the low to mid 50s across much of the region.

Previous discussion...
the vertically stacked low of the mid-Atlantic coast is quickly
filling and will gradually lose its identity by Thursday as
heights continue to rise in the powerful upper level ridge over
the region. The last of the steadier rain will exit the area
this evening. This will leave the region in a moist southerly
flow under a strong subsidence inversion. The result will be low
clouds, fog, and drizzle tonight into the Thursday morning. The
unusually high dew points in the 50s will probably lead to
widespread fog tonight and consideration will have to be given
to a dense fog advisory as the evening progresses. Temperatures
will only fall several degrees tonight. Highs on Thursday will
be higher than today as the sun slowly lifts the low clouds. The
onshore breeze will keep coastal temperatures in the upper 40s
to lower 50s.


Short term /tonight through Saturday/...
a cold front is expected to approach from the west Friday and
cross the region Friday evening. A second cold front will move
across the region Saturday. These systems are expected to
produce showers on both days.


Long term /Saturday night through Wednesday/...
high pressure is then expected to move into the state on
Sunday. Intense low pressure will move northward into the Great
Lakes Monday. A warm front extending to the east of this low
will cause rain to develop across the area Monday. The rain will
continue into Tuesday as well as a cold front moves across New
England behind the low and another area of low pressure develops
along the cold front. Showers are expected to persist in
northern areas into Wednesday as well.


Aviation /04z Thursday through Monday/...
near term: LIFR to vlifr in fog and drizzle can be expected
tonight for all terminals. Conditions will slowly lift to IFR
Thursday morning...with a few sites reaching low MVFR cigs in
the afternoon.

Short term: MVFR/VFR conditions are expected Friday and
Saturday. VFR conditions are expected Sunday. IFR conditions are
possible Monday.


near term: the very stable and humid air moving over the cold
waters led to a sizable reduction in model winds and seas. As a
result, have downgraded the Small Craft Advisory to an Small Craft Advisory for hazardous seas.

Short term: have used the GFS to initialize the wind grids
through Saturday then transition to the super blend winds. For
waves: with sea surface temperature still near 40 degrees f. And
air temperature several degrees warmer, winds above boundary
layer having a difficult time getting down to the surface. Have
initialized the wind field with GFS then manually adjusted
winds lower. Will use the nearshore wave prediction system run
on forecast wind speeds, however nwps boundary smaller than area
of cold sea surface temperature so boundary wave heights still
too high. Will therefore lower nwps waves 2 feet through


Tides/coastal flooding...
highest tides of the month will occur over the next several
days. The current weather system is producing southeasterly
waves, however wind speed in the Gulf of Maine has been reduced
due to the relatively cold sea surface temperature. This will
also reduce wave heights, so therefore wave runup or beach
erosion is not expected at this time.


Car watches/warnings/advisories...
Marine...Small Craft Advisory for hazardous seas until 2 am EDT Friday
for anz050-051.



Near term...duda/Hewitt

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