Area Forecast Discussion
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FXUS61 KBUF 011837
Area Forecast Discussion
National Weather Service Buffalo NY
237 PM EDT FRI JUL 1 2016
It will be a beautiful Fourth of July weekend across the region...
as expansive high pressure over the Upper Mississippi Valley will
gradually build across the Ohio Valley. This will promote sunny
skies for all three days of the holiday weekend along with day to
.NEAR TERM /THROUGH SATURDAY/...
A cold front crossing the Lower Great Lakes will keep unsettled
weather in place across the bulk of Western and North Central New
York through the remainder of the afternoon into the early evening
The front...which was crossing the eastern half of Lake Erie at
18z...will make its way across the remainder of the forecast area by
00z. A southwest lake breeze is strengthening ahead of the front...
and while this will help to shield parts of the IAG Frontier through
nightfall...the remainder of the region will have the risk for
strong thunderstorms. The airmass...which was initially stabilized
by the passing of this mornings showers...has had several hours of
partial sunshine to allow SBCAPEs to recover to more than 500 j/kg.
As the front encounters this increasingly unstable airmass...we can
expect more storms to fire up...particularly over the Southern
Tier...Genesee Valley and portions of the Finger Lakes. 0-6km shear
in this area will be in the vcnty of 40kts...so strong to severe
storms will be possible.
Meanwhile...the line of showers and thunderstorms that moved across
the far western counties during the morning and midday will cross
the Eastern Lake Ontario region through 21z. This should limit the
threat for severe weather with the actual cold frontal passage...as
there should be little time for renewed destabilization.
Tonight...the cold front will exit the region while expansive high
pressure over the Upper Mississippi Valley will gradually make its
way across the mid Western states. Notably drier air will be
circulated into our region in the process...and this will lead to
the return of fair weather along with more comfortable temperatures.
The mercury will drop into the low to mid 50s for most areas...
with 40s anticipated for the bulk of the Southern Tier.
For Saturday...the large area of high pressure centered over the Mid
Western states will expand across the Lower Great Lakes. While a
subtle shortwave embedded within the cyclonic upper level flow could
touch off a brief shower across the North Country...the remainder of
Western New York will enjoy full sunshine with temperatures only
climbing into the 70s.
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
A slow moving 500mb low over Quebec and ridging over the Northern
Plains states will yield a confluent flow over the Lower Great Lakes
region through the remainder of the extended Independence Day
Holiday weekend. This flow combined with weak surface high pressure
will provide dry weather with mainly clear skies outside of some
limited passing high clouds and limited diurnal cumulus. While
temperatures will average near normal Sunday, slight warming aloft
will lead to highs on Independence Day mainly in the low to mid 80s.
Lows Saturday night will be on the cooler side with drier air in
place but by Monday night a boost in dewpoints will lead to lows
near or just above normal.
.LONG TERM /TUESDAY THROUGH THURSDAY/...
The big story during the shortened work week next week will be on
temperatures climbing well above normal. The upper ridging over the
Central States on Tuesday is forecast to shift over the Eastern
States by late week with 500mb heights building to 582DM or higher
in response to a sharp shortwave diving across the Pacific
Northwest. The GFS is more aggressive than the ECMWF building
heights over 588DM. This difference is also present in 850mb Temps
with the GFS showing +22C while the EC is below +20C. A warming
trend in day to day temps is reflected in the official forecast
based on the expanding ridging. High temps should run in the mid to
upper 80s for most with at least low 90s across the warmer valleys
possible Wed-Fri. Dewpoints climbing back into the 60s will bring a
return of elevated humidity with muggy overnight temps only slipping
back into the 60s mid to late week.
In terms of rainfall, much of the week looks dry only furthering our
current run of below normal precipitation. Models do show a
potential for some showers and thunderstorms as instability and
dewpoints build Thursday and Friday but timing of upper support from
any shortwave troughs will be key in coverage. Have included
slight/low chance POPs for now until the pattern becomes more clear
late in the week.
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
While VFR conditions can be expected to dominate the region this
afternoon...there will be some showers and potentially strong
thunderstorms to contend with. The greatest threat for strong
convection will be over the Finger Lakes and eastern Lake Ontario
regions...but given that a cold frontal passage is not expected
until late afternoon...a thunderstorm will be possible for any TAF
VFR conditions will then persist in the wake of the front tonight.
The only exception could come in the Srn Tier valleys where a little
fog could develop after 06z.
Saturday to Tuesday...VFR expected.
A cold front will cross the Lower Great Lakes late this afternoon
and early evening. Gusty southwest winds will accompany this frontal
passage over Lake Erie...then in the wake of the front...winds will
freshen on Lake Ontario later tonight and Saturday. The stronger
winds will support the current small craft advisories.
As high pressure over the Mid West on Saturday builds across the
Lower Great Lakes Saturday night and Sunday...winds and waves will
lower. This will lead to more favorable recreational boating
conditions as we work into the second half of the long holiday
NY...Beach Hazards Statement until 11 PM EDT this evening for
MARINE...Small Craft Advisory until 11 PM EDT this evening for LEZ040-
Small Craft Advisory from 11 PM this evening to 8 AM
EDT Sunday for LOZ043>045.
Small Craft Advisory from 11 PM this evening to 8 PM EDT
Saturday for LOZ042.