620
FXUS61 KALY 281829
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
229 PM EDT Tue May 28 2024

.SYNOPSIS...
Scattered showers and isolated thunderstorms possible this
afternoon as an upper level disturbance tracks over the region
under partly cloudy skies along with much lower humidity. A few
showers linger tonight, especially in the higher terrain, before
a secondary cold front tomorrow results in increased shower and
thunderstorm coverage, especially south of Interstate 90. Much
cooler and drier air arrives Thursday before a warming trend
ensues for the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 11am, forecast remains on track with the leading edge of
the upper level trough and associated cold pool aloft advancing
eastward across eastern NY into western New England today. A
line of showers has developing along the leading edge of the
cold pool into the southern Adirondacks and Mohawk Valley. In
addition, a increased cloud coverage canopy is also spreading
eastward but some partial breaks of sun should return this
afternoon as mid-level moisture dries out and deeper mixing
ensues beneath the steepening lapse rates. However, generally
expecting mostly to partly cloudy skies as temperatures exceed
their respective convective temperature.

Speaking of steeper mid-level lapse rates, a few isolated to
scattered non-severe thunderstorms are possible this afternoon
thanks to lapse rates reaching 6.5 - 7C/km under the incoming
cold pool. SPC has outlined our entire area in general thunder
which matches with our expectation. Some brief downpours are
possible under any short-lived storm.

Otherwise, the deeper boundary layer mixing will keep winds
breezy with southwesterly to westerly gusts up to 25kts
possible, especially in the Mohawk Valley due to channeled
flow. With mild air still in place aloft (10C ALY 12 UTC
sounding), afternoon high temperatures should reach into the mid
to upper 70s with even low 80s in the mid- Hudson Valley.
Cooler temperatures in the southern Adirondacks and southern
Greens thanks to increased cloud coverage only reaching into the
60s.

Heading into tonight, moist cyclonic flow continues as the upper
level disturbance and trough tracks overhead. This will keep
cloud coverage and milder temperatures around. Some showers are
still possible, especially in the southern Adirondacks,
northern Catskills and southern Greens, as westerly flow
upslopes the terrain. Overnight lows only drop into the mid to
upper 50s thanks to the clouds.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...

Our upper level trough and cold pool aloft remains overhead
for tomorrow with a secondary cold front and trough axis on the
approach. The moist cyclonic flow will keep skies partly to
mostly cloudy once again, especially once we reach our respective
convective temperature. High temperatures fall a few degrees
below Tuesday`s highs only reaching into the low to mid 70s with
60s in the hill towns and higher terrain. As a secondary cold
front tracks through the region from northwest to southeast
midday into the afternoon, winds shift from westerly to
northerly and look to provide decent low-level forcing to
generate scattered showers. Dew points rise into the mid-50s
south of I-90 which, when combined with steepening mid-level
lapse rates reaching 6.5 to 7C/km, will support sufficient
instability. CAMs and high res guidance are in good agreement
with SB CAPE values climb up to 500 - 1000J/kg by midday into
the afternoon. As the wind shift boundary and upper level trough
approach, a few thunderstorms will likely develop with the best
chances near and south of I-90. Severe weather is not expected
but any storm can produce brief downpours.

Troughing continues into Wednesday night with our wind shift
boundary/secondary cold front stalling near or just south of
the mid-Hudson Valley, eastern Catskills, and NW CT. With a compact
shortwave rotating around the base of the trough and interacting
with the boundary overnight, additional showers are possible
again mainly south of I-90 Wednesday night. Some lingering
instability Wednesday evening could support isolated
thunderstorms. Incoming dry air across the southern Adirondacks,
Mohawk Valley, and Upper Hudson Valley will support at least
partial clearing skies overnight while areas south of I-90
likely stay mainly cloudy. Where clouds can partially clear
temperatures should cool into the low to mid 40s thanks to the
northerly wind shift advecting in a cooler and drier air mass.
Areas further south should remain milder in the low to mid 50s
thanks to the clouds.

Expecting a seasonably cool and mainly dry day for Thursday as
northerly winds advect in a cooler and much drier air mass from
Canada. With the boundary shifting further south and the
shortwave from Wednesday night exiting into New England by early
morning, Thursday has trended drier. In fact, morning clouds
should given way to increasing sun through the day with
decreasing dew points. PWATs even drop to 0.30 - 0 50" as
northerly winds become a bit breezy during the afternoon as
large scale high pressure builds into western NY/PA tightening
the sfc pressure gradient. Increased winds a bit from NBM to
show winds gusts reaching up to 20kts during diurnal peaking
heating hours. While the incoming air mass is quite cool (850
hPa isotherms +5 to +7C), the enhanced boundary layer mixing
should help afternoon temperatures reach into the low 70s in the
Hudson and Mohawk Valley with low to mid 60s in the hill towns
and higher terrain. Otherwise, POPs has trended lower with only
slight chance POPs now for portions of western New England and
rain-free forecast elsewhere.

Ideal radiational cooling expected Thursday night thanks to
clearing skies and northerly winds maintaining a cool/dry
Canadian air mass. With dew points dropping into the 30s to low
40s and winds turning light/variable in response to high
pressure building eastward, expecting chilly temperatures
Thursday night. Blended in NBM10th percentile guidance to
capture the chilly temperature potential. Morning lows should
drop into the mid to upper 40s with upper 30s to low 40s in the
southern Adirondacks and southern Greens.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Upper-level troughing departs eastward by Friday morning, with
narrow but high-amplitude upper ridge and associated subsidence and
surface high pressure expected to build in through the weekend. Dry
weather with mostly sunny skies are therefore expected Friday and
Saturday, while there is lower confidence in the large-scale pattern
for the far side of the weekend and into next week. The most likely
outcome at this lead time will see dry and warm conditions continue
through Sunday and much of Monday before an upper-level shortwave
approaches from the Midwest and Ohio Valley, bringing chances for
rain showers into Tuesday.

Temperatures through the period look to trend upward each day. With
cool northwest low-level flow in place on Friday, temperatures
remain near to below normal, reaching afternoon highs in the 60s in
high terrain and low to mid 70s at lower elevations, before dipping
to overnight lows in the 40s across the region thanks to efficient
radiative cooling. As ridging builds in, temperatures warm a few
degrees each afternoon, reaching highs on Monday in the 70s in high
terrain and low to mid 80s at lower elevations. Overnight lows
similarly trend toward more mild values, with temperatures Monday
night only falling into the 50s across the region.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Through 18Z Wednesday...All terminals currently seeing VFR
conditions, which should generally be the theme through the rest of
the afternoon. Scattered showers are expected across the region this
afternoon, and some brief MVFR vsby reductions are possible if any
showers move over one of the terminals. Have handled this with VCSH
and tempo groups through this afternoon. Showers diminish early
tonight with the loss of daytime heating. Another batch of showers
is possible tonight, mainly between 6-12z at GFL and possibly
ALB/PSF. Initially VFR conditions trend down to MVFR at these TAF
sites after 6z, lasting through around or shortly after sunrise.

Tomorrow morning, any MVFR cigs lift back to VFR with dry conditions
to start the day. Additional showers develop by late morning at
ALB/PSF/POU, so have included VCSH groups at these TAF sites for the
last few hours of the TAF valid period. Outside of showers, mainly
SCT to BKN mid-level clouds and VFR conditions should prevail
tomorrow morning.

Winds will be from the west/southwest this afternoon at 5-10 kt with
some gusts of 15-20 kt, especially at ALB/PSF. WInds diminish to
around 5-8 kt from the west at ALB/PSF after sunset tonight, and
become light and variable at 5 kt or less at GFL/POU. Winds tomorrow
morning increase to 5-10 kt from the west at ALB, but remain at 5 kt
or less from the west/northwest at all other terminals.

Outlook...

Wednesday Night: Low Operational Impact. Isolated SHRA...TSRA.
Thursday: Low Operational Impact. NO SIG WX.
Thursday Night: No Operational Impact. NO SIG WX.
Friday: No Operational Impact. NO SIG WX.
Friday Night: No Operational Impact. NO SIG WX.
Saturday: No Operational Impact. NO SIG WX.
Saturday Night: No Operational Impact. NO SIG WX.
Sunday: No Operational Impact. NO SIG WX.

&&

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

&&

$$

SYNOPSIS...Speciale
NEAR TERM...Speciale
SHORT TERM...Speciale
LONG TERM...Picard
AVIATION...Picard