580
FXUS61 KALY 161532
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
1132 AM EDT Tue Jul 16 2024

.SYNOPSIS...
Hot and humid conditions continue today with scattered strong
to severe thunderstorms developing this afternoon and evening. A
cold front will bring additional scattered thunderstorms
Wednesday along with continued warm and humid conditions. Cooler
and much less humid conditions along with fair weather will
follow in the wake of the front for Thursday into Friday.

&&

.NEAR TERM /UNTIL 8 PM THIS EVENING/...
** Scattered to numerous severe thunderstorms are expected this
 afternoon across eastern NY and adjacent western New England
 from 3 PM through 9 PM this evening **

.UPDATE...As of 1130 AM EDT, satellite imagery shows an MCV
approaching western New York with deep convection already
developing in the vicinity of the MCV. 12z CAM guidance
indicates that additional convection will develop as the MCV
continues east with forecast vertical wind shear supporting
linear storm modes and bowing line segments. A well mixed sub-
cloud layer characterized by DCAPE of 750-1000 J/kg will support
strong downdrafts and a 30% chance of damaging winds. There will
also be a low chance (2% within 25 miles of a point) for
tornadoes, particularly within northwest to southeast oriented
line segments, with 0-3 km SRH ranging from 100-250 m2/s2 ahead
of the line. A watch will likely be issued for portions of the
CWA early this afternoon.

Main updates to the forecast were to better reflect the timing
of thunderstorms. The line of thunderstorms is currently
expected to approach the western Mohawk Valley between 3PM-5PM,
reach the Capital Region/upper Hudson Valley/southern
Adirondacks between 4PM-6PM, and be exiting the eastern
portions of the CWA between 7PM-9PM.

&&

.SHORT TERM /8 PM THIS EVENING THROUGH THURSDAY NIGHT/...
Ongoing showers/thunderstorms should shift east of the region by
10 PM. In their wake, expect partly cloudy skies with patchy fog
forming. Lows mainly 65-70.

Another active day possible Wednesday, with greatest chances for
scattered severe thunderstorms generally from the Capital Region
and points south and east, where greatest instability (HREF mean
MUCAPES 1000-1500+ J/kg) overlaps modest deep layer shear (0-6
km shear ~30-35 KT). Deep layer shear will be stronger farther
north, however instability will be more questionable for these
areas as a pre-frontal trough may scour out higher dewpoints and
better instability prior to peak heating and approaching cold
front. SPC has placed areas from the Capital Region south and
east, including southern VT, within a Slight Risk for severe
thunderstorms, with a Marginal Risk for the remainder of the
region. Isolated to scattered damaging wind gusts appear to be
the greatest severe thunderstorm threat.

Lingering showers/thunderstorms Wednesday night, which could
even linger into Thursday morning across the mid Hudson
Valley/NW CT region as a wave developing along the front and
sharpening upper level trough approaches from the west. By
Thursday afternoon, cooler and much less humid conditions
overspread the region, with a mix of sun and clouds and somewhat
breezy conditions developing (west/northwest winds possibly
gusting up to 25 mph). Max temps should reach the lower/mid 80s
in valleys, with mainly 70s for higher terrain areas. Dewpoints
should fall into the mid 50s to around 60 in the afternoon.

Mainly clear and cooler for Thursday night, with lows in the mid 50s
to lower 60s for many areas, with some 40s possible across
portions of the southern Adirondacks.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Much of the long term period will be dry with seasonable
temperatures. High pressure will remain anchored across the
region Friday into Saturday with dry weather and comfortable
humidity levels. A weak cold front will slowly push southward
later Saturday through Sunday, but may have little to no
moisture to work with. In addition, we may be under the
influence of mid-level confluent flow. As a result, most areas
could remain dry, but an isolated shower cannot be ruled out.
High pressure then reestablishes itself on Monday with continued
dry and comfortable weather. Highs each day will be in the 70s
and 80s with lows in the 50s and 60s.

&&

.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
Through 12z/Wed...Cigs have lifted back to VFR and should remain
VFR into the early afternoon hours. A broken to solid line of
showers and thunderstorms is expected to cross the TAF sites
later this afternoon and evening, especially between 21z/Tue and
00z/Wed. Have reduced the PROB30 groups to 2 hours for the most
likely timing of the storms. Gusty winds can occur with these
storms along with reductions to IFR/MVFR.

Cigs/vsbys should lift back to VFR in the wake of these storms
with precipitation chances ending. There is some uncertainty on
whether or not any patchy low level stratus and/or fog develops
overnight. Will refer to later outlooks to address this
potential.

Wind will become south to southwesterly at 7 to 15 kt today with
a few gusts to around 20 kt, then decrease to less than 10 kt
tonight.

Outlook...

Wednesday Night: Moderate Operational Impact. Scattered SHRA...TSRA.
Thursday: No 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.

&&

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...Heat Advisory until 8 PM EDT this evening for CTZ001-013.
NY...Heat Advisory until 8 PM EDT this evening for NYZ038>041-043-
     049-050-052-053-059-060-064>066-083-084.
MA...None.
VT...Heat Advisory until 8 PM EDT this evening for VTZ015.

&&

$$

SYNOPSIS...Gant/KL
NEAR TERM...Humphrey
SHORT TERM...KL
LONG TERM...Rathbun
AVIATION...Rathbun