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000
FXUS61 KBUF 251015
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
615 AM EDT Thu Apr 25 2024

.SYNOPSIS...
Canadian high pressure will build southeastward across our area
today...before slowly drifting to the New England coastline Friday.
The high will provide us with fair dry weather through Friday...with
below normal temperatures today and tonight giving way to somewhat
above average readings on Friday as a southeasterly return flow of
milder air overspreads our region. The warming trend will then
continue over the weekend and into early next week...resulting in
summerlike warmth engulfing our region both Sunday and Monday. While
there will also be some showers and thunderstorms around,
particularly during Saturday...a fair amount of dry time can also be
expected.

&&

.NEAR TERM /THROUGH TONIGHT/...
...Unseasonably Cold Conditions Expected Again Tonight...

Sprawling Canadian surface high pressure will settle directly across
our area today...then will only begrudgingly begin to drift eastward
tonight. Aside from some patchy valley fog across the Southern Tier
early this morning...this will result in continued fair dry weather
throughout this period...along with largely clear skies. Given the
cool airmass temperatures will remain solidly below normal...with
today`s highs struggling to get much above the mid 40s to lower 50s
in most places even in spite of abundant sunshine...with the coolest
readings found across the higher terrain and along the south shore
of Lake Ontario...where developing onshore flow will keep things
cooler. Another downright cold night will then follow tonight...with
lows ranging from the lower 20s east of Lake Ontario to the mid and
upper 20s across much of the rest of the area...and to around 30
close to Lake Erie.

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY/...
Surface high pressure centered across New England will ridge back
across our region resulting in fair and sunny weather for Friday.
After this, a trough of low pressure will track into the Western
Great Lakes with an associated warm front moving across the area
Saturday. 00Z model guidance is a bit slower with this, with a mid-
level ridge keeping our region rain-free until late Friday night
when some showers could enter far Western NY. The front will be far
removed from the parent low, with a weakening trend as it moves
eastward across the area Saturday into Saturday night. For Sunday,
the risk for showers will mainly be instability/diurnally driven.
Hedge on the lower side of model guidance for PoPs due to the
convective nature of the precipitation, especially downwind of the
lakes Sunday afternoon. Following the warm frontal passage some
thunder may occur Saturday night and Sunday with limited MUCAPE
values less than 500 J/KG.

It will be warmer with the warm frontal passage, especially in areas
near the lakeshores which benefit from a southerly downslope flow.
Highs on Friday and Saturday will mainly be in the upper 50s to mid
60s, and it could be a bit warmer than that Saturday depending on
the timing of the showers. Temperatures will climb into the 70s at
most locations for Sunday.

&&

.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
An upper level ridge axis across the area Sunday night will
gradually shift to the east through mid-week. This will result in
above normal temperatures and `mostly` rain free weather for Sunday
night and Monday. Monday will almost feel summer-like with highs
reaching 80F at many locations.

As a surface low marches toward Quebec Monday night through Tuesday,
its attendant surface cold front will approach the region from the
west and then cross from west to east. Initially expect some
thunderstorms ahead of the front`s arrival Monday night and then
rain showers with the front`s passage Tuesday. Additionally with the
front`s passage Tuesday, expect temperatures to be cooler than
Sunday and Monday with highs ranging in the upper 60s to low 70s,
though still well above average for the end of April. A secondary
cold front will then cross the area from north to south Wednesday
supporting a small chance for a few rain showers.

&&

.AVIATION /10Z THURSDAY THROUGH MONDAY/...
Canadian high pressure centered north of Georgian Bay will build
directly overhead today...before slowly drifting east to eastern New
York and western New England tonight. Aside from some patchy valley
fog and attendant localized reductions across the Southern Tier
early this morning...this will guarantee fair dry weather and
unlimited VFR conditions right through the TAF period.

Outlook...

Friday...VFR.

Saturday...VFR/MVFR with some showers likely and an isolated
thunderstorm possible.

Sunday and Monday...Mainly VFR with a chance of showers and
thunderstorms.

&&

.MARINE...
Sprawling high pressure centered north of Georgian Bay will continue
to build across our region today...before slowly drifting east to
eastern New York and western New England tonight. This will provide
our region with fair dry weather and light to modest winds through
tonight...with local lake breeze circulations developing on Lake
Ontario during the course of today and resulting in winds there
turning locally onshore around 10 knots. Meanwhile on Lake Erie
northeasterly winds of 10-15 knots are expected today...resulting in
some chop even though conditions will remain below advisory criteria.

On Friday the surface high will slide east to the New England
coastline...with a general easterly to east-northeasterly flow
continuing across the Lower Great Lakes. On Lake Ontario winds will
be more easterly...and could become strong enough to bring some
marginal SCA conditions to the southwestern shore of the lake during
the afternoon.

&&

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

&&

$$

SYNOPSIS...JJR
NEAR TERM...JJR
SHORT TERM...Apffel
LONG TERM...Apffel/EAJ
AVIATION...JJR
MARINE...JJR