664
FXUS61 KALY 130140
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
940 PM EDT Fri Jul 12 2024

.SYNOPSIS...
A coastal disturbance will drift northward along the East Coast
with some showers and thunderstorms tonight into tomorrow
afternoon. Locally heavy downpours embedded within these showers
and storms will pose the threat of localized flooding. Dry
weather returns briefly for Sunday before unsettled conditions
are expected for much of next week. Warm, humid conditions are
anticipated to persist into the beginning of next week with
confidence increasing in heat indices potentially reaching
dangerous levels.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
.UPDATE...As of 940 PM EDT, showers are slowly beginning to
increase in coverage across the region as an upper- level
shortwave lifts northward across the region. These showers are
located mainly along and just to the west of the Hudson Valley
and will slowly track eastward through the overnight. The
precipitable water value on the 00z KALY sounding rose to 1.89
inches. Therefore, some locally heavy downpours are possible
with some of these showers resulting in some ponding of water
in low- lying and poor drainage areas. Some weak instability
also seen in the KALY sounding plus SPC mesoanalysis will
suggest a rumble of thunder cannot be ruled out with some of
this activity, but no severe weather is expected. Outside of
these showers, it will be a partly to mostly cloudy and muggy
night with lows mainly in the 60s to around 70 with some upper
50s in the southern Adirondacks.

Previous Discussion:
Throughout the night tonight, moisture will continue to surge
northward with an area of low pressure currently situated along
the Southeast Coast beginning to track northward. Showers and
perhaps a thunderstorm or two will develop along and ahead of
the surface boundary, primarily within the Mid-Hudson Valley and
southwest New England. With PWATs increasing to exceed 2" in
these areas, some locally heavy downpours are anticipated with
these showers and embedded thunderstorms which could lead to
localized urban and poor drainage flooding. Additionally, some
showers and an isolated thunderstorm or two will be possible
within the Capital District, Upper-Hudson Valley, and southern
Vermont with the eastward shift of the mid/upper shortwave.
Higher PWATs in these areas (1.5" to 2") will also allow for the
possibility of localized downpours.

Low temperatures tonight will range from the low to mid 60s
above 1000 ft with upper 60s to low 70s in valley areas.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
Moisture will continue to stream into the region tomorrow
morning as the aforementioned coastal disturbance progresses
farther northward. Additional showers and thunderstorms will be
possible especially within the Mid-Hudson Valley, Northwest
Connecticut and southwest Massachusetts as the stationary
boundary remains in place. With moisture remaining elevated,
locally heavy downpours will continue to be possible with any
shower or thunderstorm that tracks through these areas tomorrow
into tomorrow afternoon. This could lead to localized flooding
especially in urban and poor drainage areas through tomorrow
afternoon especially for Litchfield, southern Berkshire,
Dutchess and eastern Ulster Counties where a Flood Watch remains
in effect until tomorrow afternoon. It is important to note,
however, that latest guidance has decreased the QPF from
previous expectation. While localized amounts of 1" to 2" remain
likely within the areas within the Flood Watch, generally
anywhere from 0.25" to about 0.75" throughout the forecast area
is expected through tomorrow. This is likely due to the
combination of the eastward track of the mid/upper-level
shortwave and the southwest flow about the high offshore acting
to divert the axis of moisture farther east away from the
region.

Showers and any thunderstorms that develop tomorrow will taper
off with the loss of daytime heating tomorrow evening, yielding
dry conditions beginning tomorrow night into Sunday as high
pressure builds in from the west. High temperatures tomorrow
will range from the upper 70s to low 80s at higher elevations
to mid/upper 80s in large valley areas. Lows tomorrow night will
span the upper 50s above 1500 ft to 60s elsewhere. Sunday will
be warm with highs primarily in the 80s with pockets of upper
70s at higher terrain regions and pockets of low 90s in the
Hudson Valley. However, with dewpoints generally looking to
remain within the 60s, heat indices do not look to meet or
exceed Heat Advisory criteria. Lows Sunday night will then fall
to the 60s.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
A generally unsettled pattern ensues for the long term forecast
period with a chance for showers and thunderstorms Monday
through Wednesday. Additionally, hot, humid conditions are
anticipated Monday and Tuesday which seem increasingly likely to
meet Heat Advisory criteria.

Heat Monday and Tuesday- Confidence continues to increase in the
likelihood of dangerous heat and humidity for the beginning of
next week. High temperatures on Monday look to reach the low to
mid 80s at higher elevations and upper 80s to low 90s (possibly
even pockets of mid 90s in the Mid-Hudson Valley). Dew points
progged to reach the upper 60s to low/mid 70s will make for heat
indices in the mid/upper 90s with pockets of low 100s in large
valley areas. Tuesday`s highs, though similar, will fair a few
degrees warmer especially in the Mid-Hudson Valley where pockets
of upper 90s are possible. Tuesday`s dewpoints will also span
the upper 60s to low/mid 70s, allowing maximum apparent
temperatures to reach the upper 90s to low 100s (pockets of 105
possible within the lower Mid-Hudson Valley). While these heat
indices certainly meet Heat Advisory criteria, it was decided
that issuance would be delayed by a few periods such that exact
indices could be determined. However, it is safe to say that
Heat Advisories will likely be needed in the coming days.

Showers and thunderstorm potential- There are chances for
showers and thunderstorms over the better portion of the long
term period with a generally unsettled pattern expected.
Coverage of convection is generally anticipated to be more
scattered Monday as a general lack of forcing will limit
widespread development. However, showers and thunderstorms
should generally increase in coverage beginning Tuesday
afternoon through Wednesday as an upper-level trough digs south
and east through the region in tandem with the eastward track of
a surface low progressing through southeast Canada. This system
will look to send a cold front through the region Wednesday
which could lead to the development of some stronger
thunderstorms across eastern New York and western New England.
There remains some timing differences in the models which will
greatly impact convective development and severity. Will monitor
trends closely going forward.

Thursday and Friday should generally be drier and cooler after
the progression of the front with highs in the 70s and 80s both
days.

&&

.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
Through 00z/Sun...VFR conditions are in place at all TAF sites
at this time, but some periods of IFR/MVFR conditions are
possible later this evening into the overnight as a stalled
frontal boundary results in some scattered showers and possible
rumbles of thunder and maybe even some low-stratus and/or fog.
Have included TEMPO groups at all sites for the most likely time
frame of showers with MVFR vsbys and/or cigs. There is low
confidence on ceiling heights and fog potential overnight and
will monitor trends through the night. KPSF may be more favored
for IFR cigs but cannot be ruled out at any of the other sites.

On Saturday, trends are favoring toward drier weather at most
TAF sites as the main area of showers shifts to the east.
However, isolated showers and thunderstorms may develop in the
afternoon. Due to low coverage, have kept all TAF sites dry at
this time. Any lower cigs/vsbys in the morning should trend back
toward VFR levels by the afternoon but brief reductions are
possible should a shower or thunderstorm cross the TAF site.

Wind will be light and variable tonight, then become south to
southwesterly at 4-8 kt on Saturday.

Outlook...

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

&&

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...Flood Watch through Saturday afternoon for CTZ001-013.
NY...Flood Watch through Saturday afternoon for NYZ064>066.
MA...Flood Watch through Saturday afternoon for MAZ025.
VT...None.

&&

$$

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