Scientific Forecaster Discussion
fxus61 kcar 221618
Area forecast discussion
National Weather Service Caribou ME
1218 PM EDT Mon may 22 2017
high pressure will move east of the region today. A weak
occluded front will cross the region late tonight. Weak high
pressure should then return across the region Tuesday and
Wednesday. Low pressure will approach from the southwest later
Near term /through tonight/...
increased wind gusts this afternoon and later this evening ahead
of the front. Also increased wind gusts Tuesday afternoon with a
fairly deep mixed layer after morning low clouds lift. Also
adjusted sky cover today...but cloudy skies will continue.
surface high pressure was cresting across the region early this
morning. The high will continue to slide east today with a
light southerly return flow developing. Some light rain showers
associated with a weakening short wave trof approaching from the
west were starting to make it into western Maine early this
morning. The 00z kcar sounding showed very dry air in the low
levels. Although couldn't rule out a few sprinkles from a mid
level cloud deck later this morning, we are not expecting much
in the way of any measurable precipitation today as the upper
ridge remains across the region into this afternoon. The best
chance of seeing any measurable rain today will be back toward
portions of Piscataquis County and northern Somerset counties.
High temperatures today will be warmest across far northern and
northeast Maine today, where highs should make it into the mid
60s. Across central and interior downeast highs will only be in
the lower 60s. It will even be cooler along the coast where an
onshore flow will keep temperatures in the mid 50s.
Rain chances will increase this evening as moisture starts to
increase in advance of the approaching occluded front from the
west. Expect cloudy skies tonight along with the chance for
showers, especially across downeast. Lows tonight will only be
in the mid to upper 40s.
Short term /Tuesday through Wednesday night/...
models now are advertising more in the way of fair wx with ptly
to msly cldy skies Tue thru Wed ngt with weak ridging Alf and at
the sfc holding ovr the rgn. This will mean that any initial
rnfl originally slated to affect msly cntrl and downeast ptns
of the rgn will now remain well S of the entire rgn. With more
in the way of sunshine, we raised fcst hi temps, spcly on Wed
with fcst aftn 925 mb temps in the mid teens c supporting hi
temps in the lower 70s across all low trrn lctns north of the
immediate coast, with coastal lctns xpctd to be cooler with a
weak sea breeze.
Long term /Thursday through Sunday/...
models cont to Show Low pres from the Midwest apchg Thu with
increasing cldnss and late day shwrs/rn, which will cont to
ovrsprd the rest of the rgn Thu eve. Rn is then xpctd to cont
thru Fri before tapering to sct shwrs Fri eve and then ending
late. Rnfl amts potentially can be sig, but given how models
have been over zealous ovr the last couple of days with rnfl
with the prior two systems, we capped Max pops to the high
likely category so as not to lock later fcst shifts into a
scenario in the events models waiver this system also.
Following the exit of the sfc and upper low east of the rgn, Sat
and sun looks to be fair. Hi temps will be cooler due to
greater cld cvr and potential rnfl Thu and Fri and then cool
advcn on Sat, followed by moderation for sun.
Aviation /16z Monday through Friday/...
near term: VFR today with light south winds. VFR will give way
to IFR kbgr/kbhb terminals aft 00z in light rain showers and
decreasing ceilings. Mainly VFR at the northern terminals
tonight with possible MVFR conditions developing in sct showers
and lowering ceilings.
Short to long term: msly VFR conditions xpctd all taf sites Tue
into Thu morn with possible MVFR clg intervals possible at ngt.
Conditions then lower to MVFR clgs/vsbys late in the day Thu in
rn then lower to IFR Thu ngt, contg thru the day Fri in rn.
near term: winds/seas will remain at sub advisory levels through
Short to long term: no sig definable Small Craft Advisory pds are xpctd thru
these ptns of the fcst, with WV hts apchg 5 ft ovr our outer
most mzs late in the week and Erly weekend as low pres tracks
ewrd thru the Gulf of ME. Went with about 85 to 90 percent of
ww3 guidance for fcst WV hts.