Area Forecast Discussion
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FXUS61 KGYX 221029
Area Forecast Discussion
National Weather Service Gray ME
629 AM EDT SUN MAY 22 2016
A weak front will stall near the international border today...while
low pressure drifts slowly northward through the Gulf of Maine
today and early tonight. The interaction of these two disturbances
will keep our weather unsettled today with abundant cloud cover
and scattered showers. Somewhat drier air will filter into the
area tonight into Monday on a northerly flow. Low pressure will
affect the region again on Tuesday with showers and perhaps a few
thunderstorms. Ridging begins to build on Wed but onshore flow may
keep a good portion of our area significantly cooler Friday and
Saturday than areas further south and west.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
625 AM...minor ESTF update to reflect the current mesonet and
radar trends in near term grids.
At 06z...a weak cold front extended from the rooftop of Maine into
southeast Quebec Province. a 1004 millibar low was centered
offshore of the DELMARVA region. For today...the weak cold front
will stall near the international border while the offshore low
drifts slowly northward into the Gulf of Maine. The upper trough
axis was centered to our west on latest GOES imagery and will
drift overhead today while closing off vicinity of the DELMARVA
region by tonight. For today and early tonight...the forecast area
will be sandwiched between these two systems with abundant cloud
cover and scattered showers. Highs today should be mainly in the
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
For tonight...drier air will begin to filter into the area on a
northerly flow with clearing spreading southward from the
mountains and foothills onto the coastal plain with any shower
activity ending during the evening hours. lows will be mainly in
the 40s with a few lower 50s for southern and coastal sections.
On Monday...we`ll see partly sunny skies north and increasing
clouds southern and coastal sections as the upper low begins to
drift northward towards New England. any shower activity should be
confined to the southern third of New Hampshire and adjacent
southwest Maine. Highs will be in the lower and mid 70s...except
in the 60s along the coast in an onshore breeze.
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Stacked low pressure off the Mid Atlantic coast Monday evening
will move northward Monday night and Tuesday and bring the
likelihood of showers to our region. With cold temperatures aloft
a few thunderstorms will be possible owing to steepening lapse
rates. Thereafter, deep layer ridging looks to build across the
northeast states Wed through the weekend. Increasing heat and
humidity won`t be far away. However, backdoor front and/or general
onshore flow north of a weak warm front may indeed keep our
region (especially in Maine) significantly cooler during the late
week and weekend. Weak short wave troughs moving through the flow
during that time may spark scattered showers and thunderstorms.
There will be a fairly thin line between summer arriving here and
onshore flow keeping things cool and cloudy. The 00z ECMWF keeps
much of Maine and portions of NH in the 50s and 60s over the next
weekend which isn`t a good sign. Such is the way spring oftentimes
goes here in northern New England. The best chance of late week
and weekend heat will be across southern NH.
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
Short Term /through Monday/...VFR...with brief lcl mvfr psbl today
Long Term...MVFR likely develops Mon night and Tue in showers.
Improvement is foreseen Wed through Thu.
Short term /through Monday/...winds will shift into the Northeast
as the surface low drifts northward through the gulf of Maine late
today and tonight. Winds will increase and seas will build with
marginal Small Craft conditions expected outside the bays tonight
into the day on Monday.
Long term...Winds and seas are generally expected to remain below
small craft thresholds Monday night through much of the upcoming
week. Perhaps some occasional 5-footers on the ocean waters.
cooler temperatures and moderate humidity levels are expected
today and Monday with good relative humidity recovery tonight. An
upper level low is expected to bring cool unsettled weather to the
area for the mid week period.
MARINE...Small Craft Advisory from 11 PM this evening to 6 PM EDT
Monday for ANZ150-152-154.