246
FXUS61 KALY 211658
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
1258 PM EDT Tue May 21 2024

.SYNOPSIS...
It will remain warm and muggy through Wednesday, with
some scattered showers and thunderstorms during the afternoon and
evening hours.  A cold front on Thursday will bring some additional
showers and storms, especially for areas south and east of Albany.
Cooler and less humid air is expected behind the front on Friday
with dry weather. Some additional showers are possible through the
holiday weekend.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 1258 PM EDT...Upper level ridge axis continues to shift
southeast of the area and now extends from the mid Atlantic and
offshore into the western Atlantic Ocean to the east of eastern
New England. Meanwhile, a compact upper level disturbance
(probably a leftover MCV) is approaching the area from Ontario.
This feature is running along the northern fringe of the
ridging, although the best dynamics looks like they will be
tracking north of the region. At the surface, high pressure is
now located offshore New England, keeping a moist and mild
southerly flow in place over the area.

Visible satellite imagery shows partly to mostly cloudy skies
over the region, with a combination of both high cirrus and some
developing cu. The clearest skies are across far southern areas,
with the most clouds across northern parts of the region.

This afternoon will be fairly warm, with the warm temps aloft
and high heights in place. Highs should reach the mid to upper
80s in the valleys, but it does not look like we will reach heat
advisory criteria. High terrain areas will be in the upper 70s
to low 80s. All areas should be seeing somewhat muggy dewpoints,
with values around 60.

MRMS imagery shows some scattered showers and thunderstorms are
starting to develop, mainly across the Adirondacks and Mohawk
Valley. A rogue shower has even formed over the Capital Region
and Catskills. The only thunder in our area so far has been
across the eastern Adirondacks. SPC Mesoanalysis still shows 0-6
km bulk shear under 30 kts across our area. MLCAPE is currently
around 500-1000 J/kg over much of the area. While the mid level
lapse rates are still fairly weak (around 6 C/km or less), there
are some steep low level lapse rates thanks to the strong solar
heating ongoing today. The best chance for gusty winds today
will be across northern areas, where some dry air aloft and the
steep low level lapse rates could allow for a downburst within a
collapsing storm this afternoon. SPC has placed this region in
a marginal risk for severe weather, which makes sense given the
aforementioned setup, although the bigger threat is likely north
and northeast of our area, where shear will be higher and the
better dynamics will be tracking.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
Tonight, any lingering showers or storms should dissipate within
a few hours of sunset with the loss of diurnal heating and
decreasing instability. Most of the night will be fairly dry
with partly cloudy skies. Any areas that see rain during the day
today could see patchy fog develop tonight with winds expected
to be light once again. We may also see some low stratus again
towards the I-84 corridor, similar to Monday night. Lows will be
a few degrees warmer than the previous night, mainly in the
upper 50s to mid 60s.

Wednesday, potent upper and surface low pressure system will be
tracking into the western Great Lakes region well to our west.
Most of the day will be dry with partly to mostly clear skies as
our region remains under the influence of upper ridging. THis
will help temperatures rise well into the 80s to low 90s for
many valley areas, so it should be even a couple degrees warmer
than Tuesday. Heat indices could get into the low 90s, but
should fall a few degrees short of heat advisory criteria.

Late Wednesday afternoon and evening, a pre-frontal trough will
approach from the west, potentially leading to development of
more showers and thunderstorms. Similar to Tuesday, CAPE values
will be quite impressive and there will be steep low-level
lapse rates and mid-level dry air that are suggestive of an
environment that could support some gusty winds and hail with
any storms, but the lack of shear should keep the severe threat
on the low side. SPC has placed our western Mohawk Valley and
ADK areas in a marginal risk for severe weather again,
Wednesday. Storms could make it as far east as the Hudson Valley
Wednesday evening or early Wednesday night, but they will be
weakening at this point with the loss of daytime heating. There
could be a few lingering showers or a non-severe thunderstorm
Wednesday night, but overall most places should dry out
especially after midnight. Wednesday night will be quite mild,
with lows in the 60s for most areas.

Thursday, they system`s cold front will finally track through
our region. The exact timing of the front in relation to peak
daytime heating will determine how widespread showers and storms
become. Currently, it looks like the cold front will pass
through our western areas Thursday morning, which will limit the
coverage and intensity of any thunderstorms. For areas south and
east of Albany, the cold frontal passage will likely occur
during the afternoon, so there should be more instability to
work with. Shear will also be more impressive than the previous
few days with 30 to 40 kt winds at 500 mb. Low-level forcing is
not overly strong, but height falls aloft and the approaching
right entrance region of the upper jet should provide additional
lift. Therefore, areas south and east of Albany could see some
stronger storms Thursday if the current forecast holds. SPC
accordingly has placed portions of the Mid Hudson Valley and
southwestern New England in a marginal risk for severe weather.
Thursday will be cooler for areas north and west of Albany with
highs in the 70s to low 80s, but temperatures out ahead of the
front will likely climb into the mid to upper 80s along the I-84
corridor.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Showers and thunderstorms will come to an end Thursday evening as
the cold front crosses the region and stalls over the mid-Atlantic
states. This will result in decreasing clouds Thursday night and
mostly sunny and less humid weather on Friday with weak high
pressure overhead. Highs on Friday will reach the mid-70s to mid-
80s.

The remainder of the forecast period will consist of a series of
upper-level shortwaves crossing the region, which will result in
additional chances for showers and possible thunderstorms. Run-to-
run consistency of these shortwaves is poor resulting in lower
confidence in timing. Latest trends suggest the better shower
chances are on Saturday and either Monday or Tuesday of next week
(pending the arrival of the next shortwave) with Sunday trending
drier (in-between shortwaves). Will cap the extended with chance
pops until confidence in timing of each shortwave increases. Highs
on most days will be in the 70s with some mid to upper 60s at times
across the higher elevations.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Through 18z/Wed...an upper level disturbance will track north of the
region through late this afternoon, potentially triggering isolated
to scattered showers/thunderstorms. The best chance for any
thunderstorms will be at KGFL, with a few showers possible at
KALB/KPSF. Can not rule out thunder at KALB/KPSF, however chances
are fairly low compared to KGFL. A brief period of MVFR/IFR Vsbys
will be possible within any heavier showers.

Any showers/thunderstorms should diminish between 21Z/Tue-02Z/Wed,
with mainly VFR conditions expected through 18Z/Wed. However, any
areas which receive showers/thunderstorms this afternoon could have
some patchy ground fog develop tonight with possible MVFR/IFR Vsbys.
This potential appears greatest at KGFL, where a period of MVFR
Vsbys has been indicated between 05Z-11Z/Wed.

Light south winds should average less than 10 KT this afternoon,
becoming mainly light/variable after sunset. Winds will then become
south to southwest at 5-10 KT by late Wednesday morning.

Winds will be stronger, and variable in direction in/near any
thunderstorms this afternoon.

Outlook...

Wednesday Night: Moderate Operational Impact. Chance of SHRA...TSRA.
Thursday: Moderate Operational Impact. Chance of SHRA...TSRA.
Thursday Night: Low Operational Impact. Slight Chance of SHRA...TSRA.
Friday: No Operational Impact. NO SIG WX.
Friday Night: No Operational Impact. NO SIG WX.
Saturday: Low Operational Impact. Slight Chance of SHRA.
Saturday Night: Low Operational Impact. Slight Chance of SHRA.
Sunday: Low Operational Impact. Slight Chance of SHRA.

&&

.CLIMATE...
Record High Temperature for May 21:

Albany: 92 in 1941
Glens Falls: 93 in 1921
Poughkeepsie: 95 in 1996

Record High Temperature for May 22:

Albany: 97 in 1911
Glens Falls: 98 in 1911
Poughkeepsie: 98 in 1941

&&

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.

&&

$$

SYNOPSIS...Frugis
NEAR TERM...Frugis/Main
SHORT TERM...Main
LONG TERM...Rathbun
AVIATION...KL
CLIMATE...Speciale