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000
FXUS61 KBUF 222350
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
750 PM EDT Tue May 22 2018

.SYNOPSIS...
Weak low pressure will track into northern New England tonight
with a few lingering showers and areas of fog tonight. High
pressure will bring a period of dry weather Wednesday through
Friday. Afternoon high temperatures in the 70s midweek will
steadily increase to the lower 80s for the start of the weekend.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
Weak low pressure across northern New York will track into
northern New England tonight. There will be a few lingering
showers along a frontal boundary associated with this low,
however this front will push into central New York this evening
with radar showing the bulk of these showers already south and
east of the cwa.

Early this evening, there are areas of fog across portions of
Lake Erie and Lake Ontario. This fog is light across the vast
majority of the area, but webcams show locally dense fog near
and south of downtown Buffalo along the immediate Lake Erie
shoreline. This fog should expand inland a bit with nightfall,
and also may spread east of Lake Ontario. Another concern for
later tonight is that if skies clear out as high pressure builds
in, this would quickly be followed by fairly dense radiation
fog. In each case, forecast confidence is too low to issue a
dense fog advisory since there may simply be a low stratus deck
which never reaches the ground. The current fog is perhaps best
captured by the HRRR guidance which suggests fog will expand
considerably inland overnight. This will largely depend on if
clouds scatter out or not.

High pressure will ridge into the lower Great Lakes late tonight,
with drier air gradually building into the region. Lows tonight
will be in the lower to mid 50s.

High pressure will expand across the region on Wednesday. There will
be some lingering stratus and fog in the morning, but this should
gradually dissipate by afternoon. High temperatures will be mainly
in the 70s, except slightly cooler along the immediate lakeshore.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH SATURDAY NIGHT/...
The weather will be absolutely spectacular across the region for the
over whelming majority of this period...as a negatively tilted ridge
within a split flow will track across the Great Lakes region. The
ridge will deamplify with time though...and this will end up placing
our region between a slow moving back door cold front to the north
and the fringes of a large shield of tropical moisture to our south.
As we start the weekend...this will eventually bring an end to the
fine stretch of weather with showers and thunderstorms entering the
picture.

&&

.LONG TERM /SUNDAY THROUGH TUESDAY/...
Better agreement among Guidance packages with suppressing the
deeper subtropical moisture well south of the Lower Great Lakes.
Over the course of the Memorial day weekend look for
temperatures to nudge upwards (U70s-L80s)along with humidity
levels as deep southerly flow will transport some of the
available subtropical moisture to our south into our region. For
now, it looks like just increasing chances for showers and
thunderstorms during the day Sunday as the northern upstream
shortwave trough over Quebec Canada influences the Lower Great
Lakes. Monday into Tuesday, a cold front will cross the region
as the shortwave passes by to our north through Ontario Canada
with additional chances for showers and thunderstorms. Drier
weather with less humidity returns late Tuesday and Wednesday as
high pressure builds at the surface and aloft over New York
State.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
The main concern for aviation is areas of low stratus and the
potential for dense fog. A southwesterly flow will mix moist
boundary layer air with the relatively cool lake waters resulting in
low stratus and fog northeast of the lakes which will impact BUF/ART
and to a lesser extent IAG. Expect mainly IFR or lower conditions at
these sites until after 06Z tonight when winds shift to the
northwest and advects slightly drier air. There is a potential for
dense fog if ceilings lower to the ground, with low forecast
confidence at these locations.

Otherwise, expect mainly MVFR conditions at ROC until skies
scattered and radiation fog develops later tonight. Expect
mainly IFR or lower conditions at JHW with lots of low moisture
trapped in a northwesterly flow behind a weak cold front.

Low moisture will gradually mix out Wednesday morning with
widespread VFR flight conditions by the afternoon.

Outlook...

Wednesday night through Friday...VFR.
Saturday...Mainly VFR. A chance of showers.
Sunday...MVFR. Showers likely.

&&

.MARINE...
Winds will not be very strong, however there will be areas of
fog due to the warm moist air across the relatively cool lake
waters. Surface high pressure will near the region Wednesday,
passing over the Eastern Great Lakes Thursday, before shifting
towards the Southeast states on Friday. This will maintain light
winds and minimal waves through the end of the week.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.

&&

$$

SYNOPSIS...Apffel
NEAR TERM...Apffel
SHORT TERM...RSH
LONG TERM...AR
AVIATION...Apffel
MARINE...Apffel