-- Discussion containing changed information from previous version are highlighted. --
231
FXUS61 KALY 081044
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
644 AM EDT Wed May 8 2024

.SYNOPSIS...
A warm front will bring some showers and isolated to scattered
thunderstorms this morning. A prefrontal disturbance and a cold
front will bring additional showers and thunderstorms in the
afternoon and early evening with a few on the stronger side.
Seasonable temperatures return on Thursday, as clouds increase
and rain moves back in from the south in the afternoon ahead of
a warm front and a low pressure system in the Ohio Valley with
unsettled weather and cooler temps continuing into Friday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 634 AM EDT...A strong mid and upper level low is moving
across the northern Great Lakes Region this morning. Mid and
upper level heights are falling ahead of a sfc low and a warm
front moving towards the NY, PA, and NJ border. The isentropic
lift is increasing, as we are seeing showers and some elevated
thunderstorms increasing across eastern NY. Showalter indices
will continue to lower to 0 to -3C over eastern NY and western
New England between 6 am and 9 am for showers and isolated to
scattered thunderstorms to continue. NYS Mesonet hourly pcpn
rates in the ALY area have approached 0.10-0.33"/hr. Some minor
tweaks to PoP trends this update.

PWATs will increase to an inch and an inch and a quarter and
the upper level dynamics will increase as the left front
quadrant of a mid and upper level jet will mover over northern
NY and southern Quebec. A period of showers and thunderstorms
will continue most of the morning, but then decrease towards
noontime, as the warm front lifts through the area. The mid
level jet will be in the 50-70 KT range enhancing the 0-6 km
deep shear.

The threat for strong to severe thunderstorms continues to be
nebulous with the best shear out of phase with the better
instability. A pre-frontal sfc trough will be moving towards
and across eastern NY and western New England in the late
morning/early pm. The 00Z HREFS indicate mean SBCAPEs in the
750-1250 J/kg range with the values closer to 1000 J/kg in the
Hudson River Valley or mainly from the Capital Region south and
east. The deep shear is strong and top heavy with the stronger
winds in the 700-500 hPa layer. Mid level lapse rates will be in
the 6.5-7C/km range based on the NAM/CMC/ECMWF from ALY south
and east. We added enhanced wording for small hail and gusty
winds south and east of the Capital Region over the southeast
Catskills, mid Hudson River Valley, southern and central
Taconics, Berkshires and NW CT. A few of the storms may be
marginally severe with 1" hail or damaging winds. SPC continues
a Marginal Risk for the entire forecast area.

Temps should rise above normal in the warm sector and due to
some downsloping off the Helderbergs/southern Dacks/eastern
Catskills we could see max temps spike with the southwest/west
flow with the prefrontal trough. Max temps were raised in the
the mid 70s to around 80F in the valleys with 60s to lower 70s
over the higher terrain. The lower 80s will be near KPOU.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
Tonight...The main cold front approaches from the west late in
the afternoon into the early evening. Additional scattered
showers or isolated to scattered thunderstorms will form with
less instability. These storms are not expected to be severe.
The best chance of showers activity will be from the Capital
Region north and west. Cold advection will occur in the wake of
the front with lows in the 40s, except lower 50s from the
Capital District south and east. We did not add any patchy fog
yet due to partly to mostly cloudy conditions and a west to
northwest breeze overnight.

Thursday...the mid level flow becomes zonal over the Northeast
in the wake of the first system. A brief break in the pcpn
action is possible in the morning, but then the old cold front
begins to lift northward again ahead of the next wave ejecting
from the Midwest into the Ohio Valley. The isentropic lift
increases again for a period of showers/rain initially south of
I-90 in the late morning/early pm but then expanding northward.
This is all occurring ahead of a positively tilted mid and
upper level trough over southeast Canada, the Great Lakes Region
and Midwest. Temps will not be able to recover from normal
seasonal readings due to thickening and lowering clouds. Highs
will be in the mid and upper 60s in the lower elevations with
50s to lower 60s over the hills and mtns.

Thursday Night through Friday night...A sfc cyclone slides east
from the Mid Atlantic Region/NJ Coast Thu night with scattered
showers persisting due to the upper level low nearby. In the
dank air mass lows will be in the 40s with some upper 30s over
the southern Greens/southern Dacks.

Yet another short-wave impulse rotating around the broader mid
and upper level trough is expected to bring another period of
rainfall on Friday. The differential cyclonic vorticity
advection will help focus the rain during the day and it will
taper in the evening. The coolest day of the week is expected
with cloudy skies and a stratiform cooled atmosphere with highs
a good 10 degrees below normal with mid 40s and mid/upper 50s
over eastern NY and western New England. The rainfall may cause
some ponding of water in a few spots. As the column cools
overnight a chilly rain will taper. A few wet snow flakes may
occur over the southern Greens. Lows will be in the mid 30s to
mid 40s.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
Unsettled conditions with below normal temperatures looks to
dominate much of the long term period, as upper level troughing
persists across the Great Lakes/northeast region. Upper level
disturbances passing through this trough will bring enhanced chances
for showers, which currently looks best on Sunday, however
isolated/scattered showers will be possible Saturday as well.

The upper level trough will gradually shift east of the region early
next week, however an upper level disturbance and associated frontal
system looks to track across the region late Monday or early Tuesday
with additional rain showers possible.

High temperatures will only reach the mid 50s to lower 60s Saturday-
Sunday, although could be even cooler if widespread showers occur.
Overnight lows mainly in the 40s, with some 30s possible across
higher elevations. Gradual warming Monday-Tuesday, with highs
reaching the 60s for many areas Monday, and mid 60s to lower 70s
Tuesday. Overnight lows in the 40s for Monday and Tuesday morning,
although some 30s will be possible across the southern Adirondacks.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
A warm front will approach from the west this morning, followed
by a cold front passing through from the northwest late
this afternoon.

Area of showers and embedded thunderstorms will continue
tracking east across the TAF sites through around 13Z-14Z/Wed. A
period of MVFR/brief IFR Vsbys and MVFR Cigs will be possible as
this passes. Behind these showers/thunderstorms, a period of
MVFR Cigs are expected with only isolated showers. A few
showers/thunderstorms may then develop between 16Z-19Z/Wed as a
wind shift line passes eastward. Coverage will be isolated at
best, so have not included mention in this set of TAFs, however
AMDs will be issued should thunderstorms develop and potentially
impact a TAF sites.

VFR conditions are then expected this afternoon and early
evening. Scattered showers may then develop and affect KGFL with
a cold front. MVFR Cigs are then expected to develop at KGFL,
KALB and KPSF later this evening behind the cold front.

Light/variable winds will become south to southwest at 5-10 KT
by mid morning, then will shift into the west after 19Z/Wed and
increase to 10-15 KT with some gusts up to 25 KT, strongest at
KALB and KPSF. Winds will become west to northwest and decrease
to 8-12 KT toward and after 00Z/Thu.

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

Outlook...

Thursday Night: High Operational Impact. Likely SHRA.
Friday: High Operational Impact. Likely SHRA...RA.
Friday Night: Moderate Operational Impact. Chance of SHRA.
Saturday: Moderate Operational Impact. Chance of SHRA.
Saturday Night: Moderate Operational Impact. Chance of SHRA.
Sunday: High Operational Impact. Likely SHRA.
Sunday Night: Low Operational Impact. Slight Chance of SHRA.
Monday: Moderate Operational Impact. Chance of SHRA.
-- End Changed Discussion --

&&

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

&&

$$

SYNOPSIS...Wasula
NEAR TERM...Wasula
SHORT TERM...Wasula
LONG TERM...KL
AVIATION...KL