673
FXUS61 KBUF 181058
AFDBUF
Area Forecast Discussion
National Weather Service Buffalo NY
658 AM EDT Mon May 18 2026
.WHAT HAS CHANGED...
Marginal Risk (Level 1 of 5) across most of western and
northcentral NY for a few stronger thunderstorms late today and
this evening that could produce gusty winds.
&&
.KEY MESSAGES...
1) Summer-like heat today through Tuesday.
2) A strong cold front will bring round of showers and thunderstorms
late Tuesday into Wednesday morning, a few of which could reach
severe limits Tuesday evening into Tuesday night.
3) Drier and cooler conditions behind the behind the cold front
Wednesday afternoon through Friday, before unsettled weather
potentially returns for the weekend.
&&
.DISCUSSION...
KEY MESSAGE 1...Summer-like heat today through Tuesday.
Mid and upper level ridging will amplify over the eastern third of
the CONUS and western Atlantic early this week, setting up a deep
southwesterly flow right into our region. A couple of low pressure
systems will cut northeast through the upper Great Lakes in between
the eastern ridge and western trough first part of this week forcing
a strong push of mid-summer like air into the lower Great Lakes and
Northeast on their eastern flank. This will help boost temperatures
well into the 80s across much of western and northcentral NY today
and Tuesday, with a run at 90F not out of the question for some of
our traditionally warmest locations across the Genesee Valley/Finger
Lakes region. Today will likely be the warmest day with the mid and
upper level ridge axis cresting over our region, with upper level
heights then falling a bit Tuesday as the ridge axis slides east of
the area. NBM max temperature output continues to be too warm, but
not as overdone as previous runs. Thus, in coordination with
surrounding offices as has been done over the past several days,
daytime highs were lowered a couple to few degrees both days. The
potential for reaching heat headline criteria continues to be low,
as dew points are expected to peak in the low to mid 60s for most of
the area, helping to keep heat indices/humidity in check. However,
this is the first time this season our area will experience true,
summer-like heat and humidity levels. Expect temperatures along and
close to the lakeshores to be a bit cooler, especially with the
still chilly lake water surface temperatures.
It will turn breezy both this afternoon and Tuesday afternoon with
gusts 25-30 mph E and NE of the lakes today, with 25-30 mph gusts
areawide Tuesday afternoon. A 35 or even 40 mph gust is not out of
the question NE of Lake Erie Tuesday afternoon, especially a bit
further from the lake away from the cool dome over and closer to the
lakeshore.
Best chances for a few showers or storms will be late today and
tonight as a weak shortwave riding the western periphery of the
ridge just grazes the western fringes of our area. The eastern
fringe of a 40-50 knot LLJ will just graze western portions of our
area during this time, so if any storm does manage to develop, it
may produce some localized gusty winds late today and this evening.
Another chance for a few showers and storms will be Tuesday
afternoon as peak diurnal heating works in tandem with another weak
mid-level shortwave, this time passing over the the area ahead of a
strong cold front approaching from the west. Scattered convection
would be mainly along and inland of any lake breeze circulations.
KEY MESSAGE 2...A strong cold front will bring a round of showers
and thunderstorms late Tuesday into Wednesday morning, a few of
which could reach severe limits Tuesday evening into Tuesday night.
Despite the timing being past the peak diurnal heating hours,
confidence in a few strong to severe storms continues to grow for
Tuesday evening and Tuesday night just ahead of a strong cold front.
CAPE values of 1500-2000 J/kg with 30-40 knots of 0-6km shear will
foster the potential for damaging wind gusts, which will be the
biggest threat. Local BUFKIT soundings also advertising "fat" CAPE
profiles, which indicates the potential for large hail as well.
Finally, 0-3km SRH values of 200-300 mean there will also be the
chance for an isolated tornado. SPC currently has the bulk of our
area outlined in a Slight Risk during this period.
KEY MESSAGE 3...Drier and cooler conditions behind the behind the
cold front Wednesday afternoon through Friday, before unsettled
weather potentially returns for the weekend.
A large area of high pressure will build into our region in the wake
of the cold frontal passage, bringing a mainly dry, but much cooler
airmass back in across the area for the middle and later half of the
week. Coolest day will be Thursday, with many locations not getting
out of the 50s. Expect a slow rebound in temperatures into the
holiday weekend with 60s and some low 70s, however an area of low
pressure approaching from the southwest may bring unsettled weather
back into our region for at least a portion of this weekend.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
For today, mainly VFR flight conditions are expected, with just low
chances for a shower or rogue storm along and inland of any lake
breeze circulations through the afternoon. It will become breezy
later this morning into this afternoon with SW gusts 20-25 knots E
and NE of the lakes.
There will be a better chance for a few showers or storms very late
today into this evening as a weak shortwave riding the western
periphery of the ridge just grazes the western fringes of our area.
The eastern fringe of an associated 40-50 knot LLJ will just graze
western portions of our area during this time, so if any storm that
does manage to develop may produce some localized gusty winds late
today and through the first half of tonight. This will also bring
the threat for a period of LLWS this evening into the overnight.
Otherwise, mainly VFR conditions expected tonight.
Outlook...
Tuesday..Mainly VFR. A chance of a few showers and thunderstorms
later in the afternoon.
Tuesday night through Wednesday...Areas of MVFR/local IFR with
showers and thunderstorms of which a few storms may contain
gusty winds, with this activity ending from west to east and
improving to VFR Wednesday morning.
Thursday through Friday...VFR.
&&
.MARINE...
The pressure gradient will gradually tighten across the lower Great
Lakes today through Tuesday. Moderate southwesterlies will bring
very choppy conditions to the west end of Lake Ontario by this
afternoon, with lighter winds elsewhere.
Winds will increase further on Tuesday ahead of an approaching cold
front. Winds and waves will likely support Small Craft Advisory
conditions by afternoon on the western portion of Lake Ontario, with
the stronger winds and greater wave action then spreading east to
the east end of Lake Ontario later Tuesday night through Wednesday
as the cold front crosses the lake. Winds on Lake Erie will be
somewhat lighter, but still strong enough to produce a moderate chop
Tuesday through Wednesday.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.
&&
$$
DISCUSSION...JM
AVIATION...JM
MARINE...Hitchcock/JM
View a Different U.S. Forecast Discussion Location
(In alphabetical order by state)
|
|
