Area Forecast Discussion
Issued by NWS Buffalo, NY
FXUS61 KBUF 261854
Area Forecast Discussion
National Weather Service Buffalo NY
254 PM EDT SUN JUN 26 2016
A weak cold front will cross the region late tonight and Monday
which will bring some showers and a few thunderstorms. A secondary
cold front will cross the area Tuesday with a few more showers and
much cooler temperatures for mid-week. Temperatures will rebound
late in the week as high pressure moves across the region.
.NEAR TERM /THROUGH MONDAY/...
The hot weather will continue late this afternoon, with high
temperatures off the lakes ranging from the mid 80s to lower 90s.
The lake breeze has reached the Buffalo airport and Niagara Falls
so these locations are probably near the highs for the day, but
downsloping should help temperatures rise well into the 90s at
Rochester. Otherwise it will be mostly sunny and dry outside of
some cumulus clouds inland of the lake breezes, and some high
clouds from upstream convection.
A weak cold front will approach the region tonight, but the bulk
of the precipitation tonight will probably come from a mid-level
wave which is forecast to move out ahead of the surface front.
Convection with this can be seen on radar developing across
western Ohio. Model guidance is good agreement that this
convection will continue to develop through this evening with the
benefit of diurnal heating. The big forecast question is how well
will this hold together as this 700-500mb wave of moisture from
this convection moves eastward into our area late tonight.
Guidance remains at odds with this, but the trend among 12Z
guidance seems hold this together longer than previous guidance,
and there is an overall increase on consensus QPF. This said,
there is still uncertainty due to the convective nature of this
and it is important to note that QPFs can be misleading due to the
very moist airmass with PWATs over 2 inches. Taking these factors
into consideration, will carry a mix of likely and high chance
POPS with consensus suggesting the best opportunity for
precipitation will be across the Western Southern Tier. Also,
while not all locations will see rain tonight showers which do
make it could be quite heavy. Elevated instability on BUFKIT
suggests that some thunderstorms are possible in heavier showers.
This will continue to be monitored as upstream convection
Otherwise, tonight will be a warm night with cloud cover and wind
limiting radiational cooling. Lows will range from the mid 60s
inland to lower to mid 70s across the lake plains.
What is left of the front will move across late tonight into
Monday, providing an opportunity for showers at it moves through.
Expect any showers to be scattered in nature Monday morning,
lacking the benefit of any diurnal instability. There may be some
diurnally driven showers or thunderstorms southeast of Lake
Ontario on Monday afternoon. Also, air behind the boundary is
only marginally colder with 850 mb temperatures still +17C behind
the subtle boundary. Drying behind the mid-level wave should allow
skies to clear in Western areas where highs should again rise into
the upper 80s to around 90.
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
An upper level trough will move from the upper Great Lakes region
toward the Northeast US Monday night through Tuesday. Underneath
this trough, there will be a few weak surface boundaries that will
move through Western NY. The first will likely come through dry
Monday night due to the shallow nature of the front together with
nocturnal timing. The second boundary will be later on Tuesday. With
daytime heating together with surface lake breeze boundaries
(northwest flow/well inland), there will be a chance for some inland
convection. 850mb temperatures will drop to about 7-9C on a
northwest flow overhead. With a well mixed boundary layer, this
should result in highs mostly in the 70s. An inland cumulus field
is also expected during the afternoon which should help to keep
Tuesday night through Wednesday night...High pressure will continue
move from the northern Plains states southeast toward the Ohio
valley. Cold advection will no longer be taking place, but with
cool air overhead, clearing skies, and light winds, both Tuesday
night and Wednesday night lows should end up in the 50s most areas
but in the 40s in sheltered locations. Highs Wednesday may end up a
touch warmer than on Tuesday with more sunshine. There may still be
some afternoon inland cumulus, but it should be less extensive than
.LONG TERM /THURSDAY THROUGH SATURDAY/...
Surface high pressure will build back into the Ohio Valley and lower
Great Lakes Thursday with a return to dry weather and sunshine.
The airmass will support highs on Thursday in the lower 80s at
lower elevations away from lake influences.
Both the GFS and ECMWF sweep a mid level trough east across Ontario
and Quebec on Friday with a trailing weak cold front pushing east
across the lower Great Lakes. This may support a few widely
scattered showers and isolated thunderstorms. The mid level trough
will still be nearby on Saturday across Quebec, and may provide
enough weak forcing to support a few more widely scattered showers
and isolated thunderstorms on Saturday.
Looking a little farther ahead, there is little hope for any
beneficial rain over the next 10 days to 2 weeks with medium range
model guidance showing nothing more than a few weak frontal passages
followed by long stretches of dry/sunny high pressure. This will
bring a worsening of the very dry soil conditions currently found
across the bulk of the area.
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
VFR conditions will prevail today with high pressure in control. A
few diurnally driven cumulus clouds above 5kft may develop inland
from the lakes this afternoon, along with some passing high, thin
cirrus. Winds will be gusty at BUF/IAG due to lake-breeze
enhancement of a southwesterly flow.
A mid-level wave is forecast to move across the area in advance of
a cold front which will cross late tonight and into Monday
morning. Showers and thunderstorms will develop to the west, and
gradually weaken as they move into Western New York. It is
uncertain how well these storms will hold together, but most
guidance suggest the line will be much weaker with just showers
and possibly a thunderstorm as it moves through late tonight.
Because the lift is from the mid-levels cloud bases should be well
in the VFR category until after the frontal passage later tonight.
This may result in a brief period of MVFR cigs across the
Southern Tier Monday morning, but drier air should move in behind
the front with increasing confidence in VFR conditions by mid-day
Tuesday...Mainly VFR with a chance of showers and possibly a
Wednesday and Thursday...VFR.
Friday...VFR/MVFR. A chance of showers or thunderstorms.
High pressure will provide fine boating conditions through this
evening, with lake breeze dominated winds generally 10 knots or
A cold front will cross the region tonight into Monday morning with
a secondary cold front passage Tuesday. Winds will increase to 10 to
15 knots with some gusts 20 to 25 knots behind these frontal
passages. Waters will become more choppy, with waves approaching
Small Craft Advisory conditions, but likely falling just short. A
few thunderstorms are possible Monday and Tuesday with locally