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279
FXUS61 KALY 131750
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
150 PM EDT Sun Jul 13 2025

.SYNOPSIS...
Warm and muggy today with a slowly approaching cold front
resulting in scattered showers and thunderstorms mainly north
and west of the Capital District before more widespread rain
and storms capable of heavy rain and brief gusty winds arrive
early this evening. Our front continues to slowly advance
eastward through the day tomorrow supporting additional areas of
rain and thunderstorms, especially for areas south and east of
the Capital District. Heavy rain leading to localized flooding
is the primary concern before confidence increases for another
period of dangerous heat for the middle to end of this week.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
Key Messages:

- Isolated to scattered flash flooding and severe thunderstorms
  possible late this afternoon and evening north and west of
  the Capital District. Additional heavy rain is possible
  tomorrow south and east of the Capital District.

- Heat indices are expected to approach but fall just short of
  advisory criteria (95F) for most valley areas today:

Discussion:
As of 2:35 AM EDT...1023 mb surface high is situated south of
Nova Scotia, while a 995 mb sfc low is tracking towards James
Bay. While we remain under ridging aloft, the surface features
are resulting in low-level southeasterly flow into the region.
This will keep us warm and muggy tonight, with low stratus
expected to continue expanding northwards between now and
sunrise. For areas that do not get into the low stratus, patchy
fog and mist are expected. Lows will generally be in the upper
60s to low 70s.

Today, the surface low occludes as it tracks further north over
Hudson Bay. A weak warm frontal boundary lifts north this morning,
putting us squarely in the system`s warm sector. Without much
in the way of large-scale forcing for ascent and a capping
inversion in place, most of the day should be dry, at least from
around I-87 eastwards. Temperatures climb into the mid to upper
80s today under partly cloudy skies, and with dew points in the
low 70s it will feel quite muggy. With continued low-level SE
flow, the warmest areas today will likely be from the Capital
District northwards into the upper Hudson Valley, where heat
indices could briefly touch 95F this afternoon. However, given
relatively limited areal coverage and short time duration of the
highest heat indices, we decided against heat advisory issuance
today for these areas.

Late afternoon/evening showers and thunderstorms are then
expected to track into western areas as the trailing cold front
associated with the surface low approaches from the west. The
biggest threat will be for heavy rain, and a flash flood watch
has been issued for southern Herkimer County this afternoon into
tonight. Please see the hydro section for more details on the
flash flood threat.

While an isolated thunderstorm can`t be ruled out after around
noon or so, the more widespread, organized activity likely won`t
make it into our western zones until after around 20z this
afternoon. We cut back NBM PoPs to be more in line with CAMs
this afternoon, especially around the I-87 corridor. There
remains a marginal risk for severe thunderstorms for the
southern ADKs and western Mohawk Valley this afternoon, as
SBCAPE values per the latest HREF increase to 1500-2000 J/KG.
Shear isn`t overly impressive, but with 20-25 kt of deep-layer
shear some loosely organized clusters of storms are expected.
The main threat with any stronger storms will be damaging winds,
as DCAPE values increase to >800 J/kg this afternoon. However,
given meager mid-level lapse rates and the fact that
instability will be starting to diminish by the time the better
forcing arrives, the severe threat doesn`t look overly
widespread, and thus the continued marginal risk from SPC makes
sense.

The severe threat should begin to diminish after sunset this
evening, although with the slow-moving frontal boundary tracking
into our western areas we will likely see continued scattered
showers and thunderstorms around well into tonight, and the
chance for showers and storms expands further to the south and
east as well. It will once again be warm and muggy, with some
additional patchy fog and low stratus.

Monday...We will be in a similar pattern and airmass as Sunday,
except the frontal boundary and chances for convection will now
be focused primarily from the Capital District south and
eastwards. SPC has placed our region in a just a general
thunderstorm risk, but would not be surprised to see this
upgraded to a marginal given plenty of instability and 20-25 kt
of deep-layer shear once again. Damaging winds would be the
primary threat with any stronger storms Monday. Heavy rain will
also be a threat with any showers and storms as the airmass
remains quite moist. A weak upper impulse approaching from the
west and upper diffluent flow will increase the forcing for
ascent, so coverage of showers and storms looks to be high
enough south and east of the Capital District that we did not
see a need to deviate from NBM likely PoPs. While it remains
quite humid, temperatures will be slightly cooler, so we are not
expecting to reach heat advisory criteria Monday. Coverage of
showers and storms should diminish after sunset as the better
upper forcing moves off to our east and instability diminishes.
Lows will be a touch cooler, dropping into the 60s for most
areas, but it will remain muggy.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Key Message:

- Heat Index values or "feels-Like" temperatures may reach the
  mid 90s to 100F in the valley areas Tuesday through Thursday.

Discussion:

Tuesday through Thursday...High pressure builds in at the
surface Tuesday with upper ridging amplifying over the east
coast. The surface high and ridge aloft then shift off to our
east Wednesday afternoon and Thursday. While a couple showers
can`t be ruled out near the I-84 corridor Tuesday near the
slowly departing frontal boundary, large-scale subsidence and
warming aloft should keep us mostly dry through Wednesday.
However, the big story will be the increasing heat. 850 mb
temperatures climb to +18 to +20C, which will translate to highs
in the mid 80s for the high terrain and low to mid 90s for
valley areas. Dew points will also remain elevated, climbing
from upper 60s Tuesday to low to possibly mid 70s by Thursday.
With heat indices of 95-100F expected, heat advisories will
likely be needed for many valley areas. At this time, Wednesday
looks to feature the hottest temperatures and highest heat
indices.

Thursday evening through Saturday...Deterministic and ensemble
guidance continues to be in good agreement for a strong cold
frontal passage late next week. There remains a lot of spread in
the timing of the frontal passage, however. If this frontal
passage were to trend faster, then Thursday could end up cooler
than currently forecast. This cold front will be accompanied by
height falls aloft and strengthening mid-level westerly flow.
So with the hot and humid airmass in place we will have to
monitor for the potential for some strong to severe storms if
the frontal passage ends up coinciding with peak diurnal
heating Thursday or Friday. Much cooler, drier, and less humid
weather is expected behind this frontal passage by Saturday as
high pressure builds in from the west/northwest.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
Through 18z Monday...Mix of VFR to MVFR conditions is expected
initially with conditions trending more to VFR in the next 1-2 hours
as low clouds become more scattered. Attention then turns to the
west as showers and storms develop across central NY along and ahead
of a slow moving front. PROB30 groups have been maintained in this
TAF for KGFL/KALB from 00-06Z Monday as some guidance maintains a
low potential for showers and storms to make it into the terminals
vicinity, though confidence remains higher at KGFL where MVFR
visibilities are possible in showers. Later tonight, southerly flow
should have a marine layer advance inland with ceilings dropping to
MVFR/IFR levels for all terminals. Some visibility reductions to
MVFR are also expected, particularly for KPSF. This marine layer
will gradually mix out during the morning, but a return to VFR
conditions is not expected until the end of the TAF period. WInds
will be out of the south/southeast around 5-10 kts with gusts near
20 kts at KALB, and will decrease to around 5 kts or less tonight.

Outlook...

Monday Night: No Operational Impact. NO SIG WX.
Tuesday: No Operational Impact. NO SIG WX.
Tuesday Night: No Operational Impact. NO SIG WX.
Wednesday: Moderate Operational Impact. Chance of SHRA...TSRA.
Wednesday Night: Low Operational Impact. Slight Chance of SHRA...TSRA.
Thursday: High Operational Impact. Likely SHRA...TSRA.
Thursday Night: Moderate Operational Impact. Chance of SHRA...TSRA.
Friday: Moderate Operational Impact. Chance of SHRA...TSRA.
-- End Changed Discussion --

&&

.HYDROLOGY...
CIRA ALPW satellite imagery already shows increasing low-level
moisture across our region, and PWAT values are expected to increase
to 1.8-2.0" ahead of the approaching cold front with warm cloud
depths >12 kft. Mid-level flow will not be overly slow at around 30
kt, but the flow will be fairly parallel to the approaching frontal
boundary, so backbuilding and training of storms will be possible.
Given the above, we collaborated with WFO BGM and BUF to issue a
flash flood watch from 2 PM this evening through 5 AM for southern
Herkimer County, as flash flood guidance is relatively lower here
compared to surrounding areas. Rainfall rates could reach up to 2"
per hour. The flood threat is greatest for the more urban areas, as
well as low-lying and poor-drainage areas. WPC has maintained their
marginal to slight risk for excessive rainfall to the northwest of
the Capital District today.

Additional showers and thunderstorms with locally heavy rainfall
are possible again tomorrow, mainly from the Capital District
south and eastwards. WPC has placed this area in a marginal risk
for excessive rainfall Monday. We will continue to message the
potential for isolated flash flooding, with the greatest threat
once again for the more urban, poor-drainage, and low-lying
areas.

&&

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...Flood Watch through late tonight for NYZ038.
MA...None.
VT...None.

&&

$$

SYNOPSIS...Speciale
SHORT TERM...Main
LONG TERM...Main
AVIATION...Speck
HYDROLOGY...Main