Area Forecast Discussion
Issued by NWS Portland, ME

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FXUS61 KGYX 260048 AAB
AFDGYX

Area Forecast Discussion...UPDATED
National Weather Service Gray ME
848 PM EDT MON JUL 25 2016

.SYNOPSIS...
A cold front will cross the region tonight, providing another
round of showers and possible thunderstorms. High pressure will
build in from the west Tuesday through Wednesday. A weak frontal
boundary will settle south from Canada Thursday and will stall
just south of the region on Thursday and perhaps Friday. Areas of
low pressure may travel along this front to our south over the
weekend.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
8:50 pm Update...
Some increase in PoPs across the northern sections at this time as
the next short wave approaches. This may keep isolated storms and
scattered to widespread showers across the northern zones
overnight...with only isolated to scattered showers expected after
2 am. Temperatures...dew points and weather grids were adjusted
with fog and low stratus already forming.


750 pm Update...
I have adjusted PoPs to come closer in line with current shower
activity. Only a couple areas of consequence this evening with
more widespread shower expected activity later tonight across the
mountains. Have added drizzle to Rockland and points east for
later tonight. No lightning has been observed so far in our
region.

Temperatures were adjusted a few degrees lower also based on
mesomodels. Sky and mountain sky grids were also nudged to clear
out somewhat quicker towards morning. We will see widespread fog
tonight...especially in areas where it rained this evening.

Previous discussion...
A weakening area of showers continue to move east through NY and
VT this afternoon and will start to affect western NH in the next
hour or two. HRRR model seems to have a good handle on this weak
disturbance...although slightly underdone. As this passes through
the region isolated thunder is possible...although most areas will
just see a brief shower as the main area of showers and
thunderstorms passes south of the region.

A second disturbance currently south of Lake Ontario is also
forecast to pass mainly south of the region although it may clip
southern areas. The short wave associated with this disturbance
will pass through the area later this evening...prolonging the
threat of mainly showers with possible thunderstorms. The showers
should move east of the eastern section of area after midnight.

Skies should begin to clear by morning with patchy fog developing
as dew points remain high.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
The area should see partly sunny skies Tuesday as a ridge of high
pressure builds into the area. A weak boundary north of the region
will allow for only a slight chance of showers in the mountains
Tuesday.

Winds Tuesday will be offshore allowing temperatures to warm to
the upper 80s to lower 90s from southern New Hampshire to much of
the midcoast area of Maine. Dewpoints will remain in the 60s
across the region so air will still feel a bit muggy.

Overnight lows Tuesday night will drop to mid to upper 50s in
mountains to the low to mid 60s southern and coastal areas with
mostly clear skies. Patchy fog is again expected.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
A weak ridge of high pressure settles over the area Wednesday with
dry conditions except maybe widely scattered convection restricted
to the mountains. On Thursday a cold front moves through the
region setting off showers and thunderstorms.

The big concern will be whether a much needed rainfall develops
over the weekend. Models differ significantly on handling of a
developing low pressure system moving east from the plains and
into the Ohio valley and Eastern Great Lakes toward the weekend.
The EURO clearly brings system much further north with
significant rain that would move into the region Saturday and
through the weekend. The other models are much further south with
the system and keep the rains to our south. For now will stick
with the superblend guidance which is a hedge of presenting a
chance of the rain across the entire area. It should be noted the
confidence is low for the weekend forecast. Temperatures will
remain mild through the period but may be cooler over the weekend.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
Short Term...MVFR to IFR conditions tonight in showers and fog
after midnight. Drizzle is possible for RKD. VFR conditions
Tuesday after any morning fog. Patchy fog possible again Tuesday
night.

Long Term...VFR conditions are expected Wednesday. A cold front
crosses the area Thursday with MVFR conditions in scattered
showers and thunderstorms. Mainly VFR conditions return Friday. An
area of low pressure passing south of the area Saturday may lower
conditions depending on the northern extent of the system.

&&

.MARINE...
Short Term...Winds and seas expected to be below SCA criteria
through Tuesday night. Showers and thunderstorms and fog may
limit visibility overnight tonight.

Long Term...Conditions to remain below SCA criteria through the
outlook period.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...None.

&&

$$

NEAR TERM...Hanes
SHORT TERM...Jensenius
LONG TERM...Marine



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