Area Forecast Discussion Issued by NWS Buffalo, NY
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000
FXUS61 KBUF 050246
AFDBUF
Area Forecast Discussion
National Weather Service Buffalo NY
1046 PM EDT Sun Jun 4 2023
.SYNOPSIS...
Dry and cool conditions tonight. A period of more unsettled weather
is expected this coming week with daily chances for some showers
and a few thunderstorms, with the best chances for showers across
the eastern portions of the region. Cooler than normal
temperatures can be expected this coming week.
&&
.NEAR TERM /THROUGH MONDAY/...
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Surface ridge across the region will continue to maintain dry
conditions through tonight. A cold front across northern Ontario
will drop southward and bring an increase in mid and high cloudiness
late tonight into Monday.
There is still a fair amount of smoke in the skies over the far
western counties of New York this evening. In fact...you may catch a
whiff or two of smoke early tonight before the smoke thins and/or
temporarily moves to the southwest. This evenings near full moon
rise was particularly red...and being perfectly timed with the just
passed "Strawberry Full Moon".
Monday...a broad upper level low will continue to wobble near the
Gulf of Maine. Shortwave trough rotating around the western side of
the low, along with some additional moisture being pulled westward
around the system will bring a risk for some spotty showers and
perhaps a thunderstorm late in the day to mainly far eastern
portions of the area.
Getting back to the wildfire smoke...the low level trajectory favors
a return to even thicker smoke on Monday. While there will be little
if any cirrus over the western counties...the sky will appear milky
white...much like a mid summer hazy day or a day with plenty of high
level cloud cover. Have this worded the actual zone forecasts to
include smoky skies. With enough mixing Monday afternoon...it is
becoming more likely that smoke could even reduce sfc vsbys to under
6 miles (MVFR levels).-- End Changed Discussion --
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.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
An upper low will remain near the Gulf of Maine Monday night through
Wednesday night. This will translate to near to below normal
temperatures and chances of showers and a few thunderstorms mainly
east of Lake Ontario.
Surface low pressure over southern Nova Scotia Monday night will
slowly retrograde into New Brunswick by Tuesday. A cold front just
north of Lake Ontario Monday evening will move south across the
region overnight. Initially, a few thunderstorms are possible as
instability wanes into the evening. Coverage will be isolated to
scattered across western NY with chances as the night goes on.
Further east, a shortwave trough will move south from Quebec and
chances of showers and thunderstorms will continue overnight. Due to
the time of day and cool conditions, any thunderstorms should be
weak. Low temperatures will fall to the low to mid 50s.
The shortwave trough will move across the region Tuesday. Any
overnight activity will be done or south of the region Tuesday
morning. As surface heating occurs, convection will begin by late
morning across the region. Cooler temperatures aloft will be located
further east with showers and a few thunderstorms forming east of
Rochester by Tuesday afternoon. Dry conditions expected west of the
Genesee River Tuesday. Highs will reach the low to mid 70s.
Showers will diminish Tuesday evening with mostly dry weather
Tuesday night. The upper level low will remain over the Gulf of
Maine with the long wave trough as far west as the Upper Great Lakes
by Wednesday morning. The region will remain under the influence of
the longwave trough with the upper level low to the east. Increasing
subsidence and drier air will be across the region Wednesday.
Diurnally driven showers are possible, mainly east of Lake Ontario
however coverage looks limited. Highs will reach the upper 60s
across the higher terrain to the low to mid 70s across the lake
plains. A strong shortwave trough will approach the region Wednesday
night. At this time, mainly an increase in cloud cover is expected
but can`t rule out a few showers, again mainly east of Lake Ontario.
Lows will fall to the low to mid 40s across the higher terrain to
the low 50s across the lake plains.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
Elongated upper level low draped from the Canadian Maritimes to the
Ohio Valley at the start of this period will slowly drift eastward
through the end of the week. Behind this system...weak shortwave
ridging should briefly build in aloft by Saturday...before giving
way to another shortwave trough/cold front dropping southeast from
central Canada on Sunday.
Given the above...we can expect another day of cooler than normal
and still somewhat-unsettled conditions on Thursday...with diurnal
heating of our cooler airmass again bringing the risk for diurnally-
driven showers...with the greatest potential for these along our
southeastern periphery (and closest to the upper level trough axis).
Meanwhile highs will mainly be in the mid to upper 60s...with lower
60s found across the higher terrain. Friday into Saturday will then
feature a trend toward progressively drier and warmer weather as the
upper low pulls away and heights/temps aloft rebound...with mainly
dry conditions and highs mostly in the mid to upper 70s expected for
the start of next weekend. By Sunday...shower and thunderstorm
chances should return with the approach of the above mentioned
shortwave trough/cold front...though temps will remain slightly
above normal with highs mainly in the 75-80 range.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
VFR conditions are expected through the TAF period.
The exceptions to this will be the first half of tonight where vsbys
could temporarily drop to MVFR levels from wildfire smoke at KIAG
and KBUF. This may prove to be a more widespread issue Monday
afternoon as a swath of thicker (and lower) wildfire smoke moves
south across the region.
Outlook...
Monday Night...Mainly VFR. Slight chance of a shower or thunderstorm.
Tuesday through Friday...Mainly VFR with a chance of showers.
&&
.MARINE...
Northeasterly flow will continue to relax through tonight on both
lakes.
The passage of a cold front will bring northwesterly winds by Monday
night with northerly component winds likely continuing through mid
week. Speeds should average less than 20 knots, but choppy
conditions will likely develop on both Lake Erie and especially
Lake Ontario with waves approaching 3-4 feet at times.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.
&&
$$
SYNOPSIS...TMA
NEAR TERM...RSH/TMA
SHORT TERM...HSK
LONG TERM...JJR
AVIATION...RSH/TMA
MARINE...TMA