Forecast Discussion

Forecast Discussion for BUF NWS Office
FXUS61 KBUF 260234

Area Forecast Discussion
National Weather Service Buffalo NY
1034 PM EDT Fri May 25 2018

Increasing southwesterly flow and sunshine will lead to warm
temperatures through the holiday weekend. There will be a chance of
a few widely scattered showers and thunderstorms each day from
Saturday through early next week, but the vast majority of the time
will be rain free.


IR satellite imagery displays clouds streaming across the North
Country and the eastern end of Lake Ontario along a nearly
stationary frontal boundary this late evening. Meanwhile to the
south clear skies rule over the remainder of the forecast area.

Overnight, southwesterly large scale flow will continue as dewpoints
start to creep up. This will keep a floor underneath low
temperatures overnight, yet dewpoints shouldn`t jump enough to make
it an uncomfortable sleeping night just yet.

The post-warm frontal ridging from Friday into Friday night will
start to break down on Saturday as an unimpressive short wave trough
moves from the central Great Lakes toward our area by Saturday
afternoon. Some increase in cloud cover will be evident with this
weak system on Saturday, however poor large scale ascent and only a
very weak right entrance region of an upper jetlet will result in
synoptic scale ascent that will have difficulty overcoming mesoscale
effects. Thus, showers and a few thunderstorms will likely be
relegated to the lake breeze boundaries and push eastward from
there. Thus, while the Southern Tier, northern Finger Lakes, and
areas east of Lake Ontario will have a chance of showers and
thunderstorms during the afternoon Saturday, it seems stabilization
from the Great Lakes should keep the bulk of the immediate
Buffalo/Niagara Falls/Rochester areas mainly dry as the system

Continued warm advection on Saturday in southwesterly large scale
flow combined with a warmer start to the day should manage to allow
for similar high temperatures on Saturday when compared to today.
This will be the case even with less insolation due to a bit more
cloud cover.


Warm temperatures will continue through the holiday weekend with
daily chances for showers and thunderstorms through Memorial Day.

Any showers and thunderstorms will taper off into Saturday
evening with the loss of daytime evening. A light southerly flow
will continue overnight with mild temperatures in the low 60s.
A shortwave trough will approach NYS Sunday while a frontal
boundary sags southwestward from North Country into Western NY.
As dewpoints rise into the mid to upper 60s Sunday, showers and
thunderstorms will likely form in vicinity of the frontal
boundary as well as any lake breezes that form. The best chance
for showers and thunderstorms will be away from the lakes in the
afternoon and early evening. Temperatures will rise into the
low to mid 80s, and slightly cooler near the lake shores.

Any showers and thunderstorms will move into Central NY by
Sunday evening however activity that forms across the Ontario
peninsula Sunday will venture eastward across Lake Erie and Lake
Ontario. This activity will move eastward while diminishing
across the forecast area Sunday night. Temperatures will stay
mild overnight with temperatures reaching the mid 60s.

Memorial Day will be warm with the potential for temperatures to
reach the mid-upper 80s to possibly 90 in interior valleys.
Dewpoints will continue to hover in the mid to upper 60s making
for a slightly uncomfortable day. An upper level trough axis
will move across the region during the day and winds will become
northerly by Monday evening. Shower and thunderstorm chances
will be mainly confined to interior areas of the forecast area
and over the higher terrain in closer proximity to a front that
should be to the south. Locations along the lake plains will be
both shadowed by the lake breezes and away from the better
moisture and forcing behind the front. Activity will taper off
into Monday evening with mostly dry conditions expected overnight.


Canadian high pressure will build across the northeast CONUS
Tuesday. This will bring a return to dry weather, as well as
give us a brief break from the heat and humidity of the holiday
weekend, with highs in the mid 70s to around 80.

The high will start to drift east Wednesday bringing back some
warmer and more humid air. The day should remain dry, but can`t
completely rule out some pops up afternoon showers or storms given
expected instability, and the potential for lake breeze development.

Mid-upper level ridge will be ushered off to the east by Thursday as
a potent shortwave approaches from the northern Plains and the
remnants of the Gulf tropical system push into the Ohio Valley. This
will bring a better chance for scattered showers and storms for
Thursday and Friday.


For the 00Z TAFS VFR flight conditions are found, and these
conditions are expected to continue through the TAF period. A few
showers will pass by the North Country through the period, though
remaining largely to the north of Watertown. A few isolated showers
and thunderstorms may develop on lake breeze boundaries across
interior WNY tomorrow afternoon, though likely forming away from TAF


Saturday night...Mainly VFR.
Sunday and Monday...Mainly VFR with scattered showers and
Wednesday...Mainly VFR.


High pressure will slowly settle to the southeast through the
weekend. A weak system will slowly advance eastward through the
Great Lakes, however as it remains to the west of the area for the
most part, southwesterly winds will be about all it creates over the
water. A weak pressure gradient will remain in place through early
next week, with winds generally under 15 knots and waves 2 feet or

There may be a few widely scattered thunderstorms at times with
locally higher winds and waves.





NEAR TERM...Fries/Thomas

NWS BUF Office Area Forecast Discussion