Area Forecast Discussion
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FXUS61 KGYX 280231
Area Forecast Discussion
National Weather Service Gray ME
1031 PM EDT Thu Apr 27 2017
A weakening area of low pressure over the Gulf of Maine will
continue to drift northeast into tonight. This will prolong the
cool damp conditions over all but far western and northern New
Hampshire into tonight. A front accompanied by showers will
move across the region Friday morning and will help to sweep out
the cool and wet conditions with warmer temperatures Friday
afternoon and into the weekend. That may be short lived
however...as cooler air tries to slip back in from the north
Sunday into Monday while low pressure approaches from the south.
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
1020 PM...Pushed patchy drizzle further south to the coast
overnight, as we are seeing a some here at WFO GYX, and KGYX
radar showing some weak echoes between the foothills and the
coast. Also made some temp adjustment based on current obs.
Temps near the coast, in the marine lyr are in the upper 40s, as
dew points, so do not expect much change here. Further inland
and to the west Tds in the mid-upper 50s, and although they may
drop off a little, have increased mins a bit in some areas
generally in the low to mid 50s.
620 PM...In this forecast updated pops a bit, more to reflect
some DZ developing in the SE upslope areas of the
mountains/foothills, especially in ME. Should see some fog
develop on the coastal plain and in the upslope areas as well.
Temps on the coast, already in the marine lyr will see drop
overnight and should be around or a little above 50. Inland
areas will see temps drop to 50-55.
Previously...Weak frontal boundary moves through from west to
east late tonight into Friday morning, and could spawn some
showers and perhaps an isolated storm. Front is weakening as
will not be a big precip producer. However, as the front moves
through, expect the low clouds and gloom to finally abate either
Friday morning in New Hampshire or around midday Friday as one
heads further east toward Augusta and Rockland.
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
Quiet weather expected Friday night with increasing clouds as a
weak progressive 500mb shortwave brings showers to the region
for the beginning of the weekend Saturday morning. Showers look
scattered in variety and instability still looks weak at this
point, thus left any mention of thunder out. It will remain
warm and moist though with dewpoints still in the 50s for most
areas. Saturday night a weak cold front pushes through ushering
in drier and cooler air for Sunday.
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
Overall Sunday looks to be seasonable with highs mostly in the
low 60s, with clouds increasing through the afternoon hours as a
warm front quickly pushes back north with return flow becoming
established. Rain chances will be on the increases Sunday night
into Monday as the warm front pushes back north. Currently looks
like the best chance for heavier precipitation across is across
Northern New Hampshire and the Western Mountains of Maine.
Showers to continue Tuesday into Wednesday as a cold front
pushes through by mid-week with drier and cooler weather
possible once again by Thursday.
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
IFR or worse tonight areawide in low clouds and fog. Conditions
improving to VFR from west to east during the day Friday behind
a frontal boundary.
Long Term...Showers expected on Saturday morning, with limited
impacts to aviation operations expected. High pressure in
control on Sunday with rain and MVFR ceilings possible once
again by Sunday night. Lower clouds and visibilities possible
Small craft for seas remains in effect through Friday.
Long Term...Winds speeds will be on the increase across the
waters during the day on Saturday with westerly flow turning
offshore by Saturday night. Seas will generally run in the 2 to
4 foot level. Seas and winds will be on the increase Monday
night into Tuesday with SCA conditions possible with south to
southwest winds over the waters.
Damp conditions with light winds persist into early Friday. A
front on Friday could bring a tenth of an inch of rain or so
late tonight or Friday morning. Lower relative humidities behind
the front late Friday into the weekend.
A Coastal Flood Advisory is in effect for later this evening
through early Friday morning due to the persistent light
onshore flow combining with the highest astronomical high tides
of this cycle. High tide at Portland is 11.7ft at 12:42am
Friday. Storm surge will run close to a half foot at time of
high tide. Some splash over and beach erosion will be possible
through the early morning hours.
ME...Coastal Flood Advisory until 3 AM EDT Friday for MEZ023-024.
NH...Coastal Flood Advisory until 3 AM EDT Friday for NHZ014.
MARINE...Small Craft Advisory for hazardous seas until 8 PM EDT Friday