Area Forecast Discussion
Issued by NWS Portland, ME

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101
FXUS61 KGYX 030741
AFDGYX

Area Forecast Discussion
National Weather Service Gray ME
341 AM EDT Fri May 3 2024

.SYNOPSIS...
High pressure near the coast will provide a drier and quieter
couple of days between today and Saturday, however it will also
contribute to a growing onshore flow this weekend. Thickening
clouds, cooler temperatures and rain showers are expected by
Sunday... with clearing likely not coming until Monday. Warmer
and sunnier conditions are expected Monday and Tuesday, then
more unsettled weather returns around the middle of next week.

&&

.NEAR TERM /TODAY/...
Impacts:
*No significant weather impacts expected

Clouds continue to roll over the ridge this morning, however a
clear slot did develop overnight allowing fog to form and some
areas to quickly drop a few degrees. Now, as the mid-level cloud
deck fills back in, fog is dissipating and temperatures are
plateauing. As the ridge moves overhead and surface high
pressure builds in today, skies will gradually clear and with
BUFKIT soundings showing a return to good mixing, high
temperatures should climb into the 60s areawide. The only
exception would be the coast where the seabreeze will keep
temperatures in the 50s.

&&

.SHORT TERM /TONIGHT THROUGH SATURDAY/...
Impacts:
* No significant weather impacts expected

Skies will remain partly cloudy overnight which will keep us
from having a widespread radiational cooling night, but with
continued light winds there is opportunity for patchy dense fog
and some quick temperature drops in areas that can find some
clear skies. Generally low temperatures look to be in the low to
mid 40s across the area with some upper 30s north of the
mountains.

The 500mb ridge axis inches ever closer, but models suggest the
offshore upper low keeps the pattern pretty blocked up for
Saturday. Expect clouds to increase through the day as we see
warm moist advection from the southwest. BUFKIT profiles
suggest another well mixed day so the clouds shouldn`t keep us
from once again climbing into the 60s across most of the area,
with the coast once again topping out in the 50s due to the
seabreeze.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
An upper level ridge this weekend is replaced by an upper level
trough to start next week, with rainy and cool weather
eventually yielding to a drier, warmer couple of days to start
the upcoming work week. Another frontal system approaches with
increasing rain chances around the middle or latter part of next
week. All in all neither of these systems look to be
particularly impactful in terms of a significant hydrological or
convective threat, and overall this will be a stretch of
typical Spring weather with an active but ultimately benign
pattern.

Starting Saturday night... high pressure along the eastern
periphery of Maritime Canada and a cold front approaching from
the Great Lakes continue to produce onshore flow into New
England. Clouds will fill in through the low and mid-levels
especially south and east of the mountains into Sunday, with
potential for fog and perhaps some patchy drizzle development
during the morning as an upper level ridge rolls overhead.
Shower chances meanwhile will increase from the west through the
day Sunday amid pressure and height falls... culminating in a
likely period of rain as a pre-frontal trough crosses Sunday
afternoon and/or evening. Although the cold front itself won`t
cross until Monday, the moisture axis will be attached to the
pre-frontal feature... with generally 0.2-0.4" of rainfall.
Temperatures meanwhile won`t warm too much on Sunday thanks to
warm advection atop the cool marine layer, with highs generally
in the 50s... coolest in the 40s along the coast.

In terms of sensible weather conditions, a question will be the
progression of the cold front itself as its passage will bring
fresh westerly flow. There will be a gap between the bulk of the
rain/deep moisture exiting late Sunday and the low-level
humidity being flushed out with the cold front on Monday. Thus,
would expect the overnight to remain a bit damp with fog and
drizzle potential.

Current model consensus mixes this out through the mid- or
late- morning hours, with a mix of sun and clouds and far warmer
temperatures on Monday. Highs are forecast to be in the 60s and
70s, coolest in the north where upsloping clouds and a few
showers are expected to remain. Light winds and the warm
temperatures should allow a sea breeze to develop. Upper level
low pressure settles across Maritime Canada and a ridge axis
nudges east toward New England. Resultant northwest flow
reinforces the drier airmass with what looks to be a great day
on Tuesday... featuring temperatures again warming into the 60s
and 70s, light flow, an afternoon seabreeze, and what will
likely be partly or mostly sunny skies.

Forecasting the upper air pattern becomes a bit fuzzy toward the
middle of next week with an increasingly blocked pattern and a
general trend toward more zonal flow over the Northeast with the
jet nearby or overhead. This introduces the potential for
shortwaves moving through the jet to bring showers across the
area... and indeed have PoP and cooler temperatures on the
increase again toward the middle of the week.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
Short Term...A mixed bag of LIFR/IFR/MVFR ceilings early this
morning will gradually improve to VFR as the day goes on. We
will most likely return to areas of LIFR in fog tonight, but
quickly improve back to VFR Saturday. Winds will be light and
variable across the area.

Long Term...Periods of IFR are likely Sat night through Mon
morning with light SE flow turning N thru Sun, then SW or W Mon.
Prolonged and more significant restrictions are most likely
along the coast with low CIGs and some lowered VSBY... with all
terminals expected to have at least a few hours of restrictions
with -RA crossing the area on Sunday. Conditions trend back to
VFR Mon, except potentially MVFR CIGs in the north... then all
VFR on Tue.

&&

.MARINE...
Short Term...Conditions hazardous to small craft are not
expected. High pressure building over the waters will keep
winds light and variable through tonight, with an afternoon
seabreeze developing. For Saturday, winds will be blowing
onshore at around 8-10 kts.

Long Term...SE flow across the waters Sat night increases to
around 10-15 kts sustained by late Sun...with potential for fog
and rain thru Mon morning. A front crossing the waters brings
clearer conditions late Mon into Tue, with light winds generally
out of the west (NW or SW) into midweek.

&&

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

&&

$$

NEAR/SHORT TERM...Baron
LONG TERM...Casey