Area Forecast Discussion
Issued by NWS Buffalo, NY

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
074
FXUS61 KBUF 132239
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
639 PM EDT Mon May 13 2024

.SYNOPSIS...
A warm front will move across the area through this evening with
some showers and a thunderstorm possible. This front will usher in a
period warm and unsettled weather which will last through the middle
of the week. After this, a weak high pressure ridge will provide
warm and mainly rain-free weather outside of a few afternoon showers.

&&

.NEAR TERM /THROUGH TUESDAY NIGHT/...
Earlier daytime heating behind a warm front and a more moist air
mass is causing some diurnal instability across Western New York
into early this evening. This will continue to support a few
lingering showers and possibly a few thunderstorms with the greatest
chances from the Genesee River Valley to Western Finger Lakes
region. Meanwhile, across far Western New York, a weak lake shadow
has developed in the moderate southwesterly flow. Temperatures as of
early this evening have warmed up to the low/mid 70s for areas west
of Rochester. Areas from Rochester eastward the warm air advection
hasn`t advanced enough yet to warm temperatures to the levels across
far western NY.

The warm front will stall from the north shores of Lake Ontario
to the Saint Lawrence Valley tonight. Chances of showers will
linger near the boundary, while the bulk of Western NY will be
rain free. Temperatures will fall to the 50s tonight.

The frontal boundary to the north will slowly sag southward
during the day Tuesday. Limited diurnal instability will develop
across Western NY, with showers and a few thunderstorms
developing Tuesday afternoon. The greatest coverage will be
south and east of Lake Ontario with slightly lower chances on
and along its immediate shorelines. Precipitable water values
nearing 1.25" not too far above climatological normals, but weak
flow aloft will result in slow storm motion. The potential
exists for repeated rainfall which could be heavy at times with
any convective activity. Modest PWAT values lower the risk for
flash flooding, but the risk is non-zero.

&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
A 500 hPa trough will pass across the Ohio Valley and the mid-
Appalachians Wednesday and Wednesday night. While most of the
showers associated with this feature will be to our south, there
will be a easterly flow of Atlantic moisture into our region that
will bring scattered showers through the day Wednesday. Highest
chances for showers will be to our east, closer to the deeper
Atlantic moisture, but also along a convergent boundary. This
boundary, southeast flow around the trough aloft, and northeast flow
from a incoming area of high pressure, will serve as a boundary for
likely PoPs through the afternoon, and into the evening hours. The
light flow could lead to some patches of fog Wednesday night in
areas where daytime rain occurred.

Highs Wednesday will reach towards 70 near the Lakes, while inland
and under deeper moisture and rain showers...mid 60s. Temperatures
at night will dip down into the mid 50s.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
A progressive flow aloft with impulses and shortwaves rippling
through will maintain chances for showers and thunderstorms this
period, with the best chances for showers and even a rumble of
thunder Friday night and Saturday with a trough passage.

To start this period, Thursday will be mostly dry, with low PWATS
and a narrow ridge of high pressure nearby...this between an east
coast low, and trough across the Plains. However there is a
possibility that a few showers from the east coast low sneak far
enough westward into our eastern CWA.

This western trough, and its additional lift, will push eastward,
likely in the Friday night to Saturday timeframe. Will place likely
PoPs with the trough passage, along with a slight chance for thunder
with MUCAPE values around 500 J/KG ahead of the trough. Behind the
trough lowering chances for precipitation, through a secondary
trough dropping out of Canada may bring chances for showers Sunday.
Temperatures Thursday through Saturday will average just above
normal, and then the final two days of this period, Sunday and
Monday will be even warmer with a milder airmass pushing northward.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
A warm front will exit north and east of the region this evening.
Behind the front, diurnal instability will support some showers in
the wake of the warm front, with a few isolated thunderstorms
possible. Southwesterly flow will result in a rain-free lake shadow
developing across the Niagara Frontier (KBUF/KIAG) into the evening.
Overall widespread VFR flight conditions, except localized MVFR
possible in vsby restrictions in any showers or thunderstorms.

Dry weather for most locations tonight as the frontal boundary
lifts northward. Some showers may linger near KART which will be
closest to the boundary. Mainly VFR flight conditions for
tonight through Tuesday morning. Chances for showers and a few
thunderstorms increase with instability Tuesday afternoon.
Mainly VFR with localized IFR in heavier showers and
thunderstorms.

Outlook...

Tuesday night...MVFR/IFR in showers, stratus, and fog.

Wednesday...MVFR/IFR with a chance of showers, along with
lingering stratus. Improving later Wednesday and Wednesday night.

Thursday...VFR.

Friday...VFR. A chance of showers late.

Saturday...VFR/MVFR. A chance of showers.

&&

.MARINE...
Moderate southwesterly flow today, but winds will be strongest
on the land due to lake breeze enhancement. Winds on the waters
expected to remain below Small Craft criteria. After this, there
will be a relatively weak flow, with winds expected to remain below
15 knots through Friday.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.

&&

$$

SYNOPSIS...Apffel
NEAR TERM...Apffel/SW
SHORT TERM...Thomas
LONG TERM...Thomas
AVIATION...Apffel
MARINE...Apffel