897
FXUS61 KALY 121916
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
316 PM EDT Sat Jul 12 2025

.SYNOPSIS...
Isolated to scattered showers and widely thunderstorms today
into tonight with any storm capable of locally heavy downpours
and brief gusty winds. Warm and muggy conditions continue
through tomorrow with a break for dry weather before a slow
moving cold front ushers in additional showers and thunderstorms
Sunday afternoon into Monday. Dangerous heat and humidity then
returns Tuesday through the end of the week.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
Key Messages:

- Localized flooding possible today from heavy downpours and
  higher rainfall rates from isolated slow moving
  thunderstorms, especially if storms repeatedly impact a given
  area.

- Isolated flash flooding is possible late Sunday P.M into
  Monday, especially if heavy rain persists over a given area as
  a cold front slowly tracks eastward. Cannot rule out an
  isolated strong thunderstorm, mainly in the mid-Hudson Valley
  and western New England on Monday.

Discussion:

Clouds have been slow to erode this morning in valley areas as
the 12 UTC ALY sounding showed a strong low-level inversion with
moisture trapped beneath it. However, latest GOES Vis/IR
sandwich satellite shows clouds finally breaking for more sun
and given dew points quite high in the upper 60s to low 70s,
increased insolation will allow the instability to rise quickly
reaching 1000 - 2000 J/kg per the 12 UTC HREF guidance. A weak
sfc trough beneath the relatively weak ridge positioned over
western/central NY will act to focus convection this afternoon
as will a few weak shortwaves rounding the top of the ridge and
southeast flow upsloping the terrain. Although instability will
be plentiful amid this muggy air mass, shear is very weak only
15 - 25kts and flow through the column is very weak. Therefore,
expecting generally isolated storm coverage although a few storm
clusters can develop along outflow boundaries and grow upscale.
Should any storms become tall enough, cloud to ground lightning
can certainly occur along with heavy downpours given FZ levels
11-12k ft and PWATs around 2" (impressively 1.85" on the 12 UTC
ALY sounding). Storms will be slow moving and the heavy
downpours could lead to localized flooding, especially if storms
redevelop or persist over a given area. Also cannot completely
rule out brief gusty winds from wet microburst again should a
storm updraft grow tall enough. Luckily, the limited storm
coverage should prevent widespread flash flooding and the WPC
Day 1 marginal ERO helps message that. Otherwise, increased sun
this afternoon will help temperatures rise into the mid to upper
80s and given high dew points, it will feel more like low to
mid 90s. A muggy night follows for tonight with isolated
shower and thunderstorms continuing this evening but gradually
diminishing overnight. Again, any storm can produce brief heavy
downpours.

We start Sunday again with morning stratus clouds as southeast
flow advects the marine layer inland with a few isolated
showers still around before the pseudo weak warm front that has
been stalled overhead finally lifts northward by mid to late
morning. This will allow our region to finally dry out a bit as
we enter into the very warm/humid warm sector. For most of
eastern NY and especially western New England, the majority of
Sunday should be dry as the slow approaching cold front will be
displaced well to our west with morning clouds giving way to
sun. Guidance shows weak height falls in response to the
incoming trough holding off reaching the western Mohawk
Valley/western Adirondacks until closer to 21 - 00 UTC.
Therefore, most of Sunday should end up being dry but definitely
warm/humid as high temperatures rise into the mid to upper 80s
making it feel more like low to mid 90s. Afternoon sun and
boundary layer mixing should help reduce dew points a bit and
thereby lowering our chance to hit the 95F heat advisory
threshold.

The line of showers and thunderstorms associated with the
incoming front reaches our western Adirondack/western Mohawk
Valley and northern Catskills areas by early evening with a
conveyor belt of slightly stronger mid-level westerlies tracking
overhead as troughing spreads eastward. Deep layer shear
increasing to 20-25 KT coincide with moderate instability 1000-2000
J/kg can support storms growing upscale enough to result in
damaging wind gusts. SPC continues a "Marginal Risk" or level 1
of 5 across areas mainly west of the Hudson River where storms
should reach during the final hours of peak heating. However,
the overall weak forcing, shear and mid-level lapse rates will
limit the severe weather threat. Besides potential wind gusts,
heavy rain and localized flooding will need to be monitored as
PWATs remain high around 2" focused along the boundary and with
high FZ levels 12-13kft supporting efficient warm rain processes
and rather unidirectional weak flow through the column oriented
parallel to the front, periods of heavy rain could train or
repeatedly impact a given area. Rainfall rates could reach
1-2"/per hour a times. While the localized flooding potential is
higher Sunday evening/night compared to Saturday, the WPC Day 2
marginal ERO is still fine to message the isolated flash flood
potential as flash flood guidance is still rather high at
2-3"/3-hours. The line of rain and embedded storms continues to
very slowly track eastward overnight resulting in more
widespread rainfall and potential additional localized flooding
from heavy downpours.

By Monday, our cold front and line of showers/embedded storms
continues to slowly progress further eastward starting the day
around the Hudson River and gradually advancing eastward into
western New England by the afternoon. Heavy rain and localized
flooding remains a concern along the boundary where rain can
train/repeatedly impact as our environment from Sunday remains
largely the same. As discussed in the previous discussion, areas
in the mid- Hudson Valley, southern Berkshire, NW CT and the
I-84 corridor will some limited heating/breaks of sun ahead of
the boundary and with lapse rates steepening closer to 6C/km
before the front arrives, storms could grow upscale and
strengthen as they progress further south/east by the afternoon.
SPC does not currently have us outlooked but will continue to
watch trends and collaborate as needed. Otherwise, temperatures
will not be quite as hot as the previous few days given
increased cloud coverage and rain but it will remain very muggy.
Cloudy skies give way to afternoon sun for the areas mainly
north and west of the Capital District as the front slowly
clears and weak troughing and mid-level moisture slowly exit. It
will take until late Monday P.M into Monday evening for clouds
and rain from the front to clear across western New England but
the northwest wind shift should help usher in some minor relief
from the very humid air mass overnight. Overnight temperatures
dropping into the upper 50s in the higher terrain to mid-60s in
the valley.

&&

.LONG TERM /TUESDAY 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:

The main story for the long term will be the dangerous heat as
broad ridging develops over the Eastern CONUS while a shortwave
in southern Canada slowly amplifies as it tracks into the Great
Lakes. This will induce stronger southwesterly flow and advect
an anomalously warm and humid air mass into the Northeast with
850 hPa isotherms reaching 1 to 2 standard deviations above
normal per the NAEFS. Sunny skies on Tuesday under a weak sfc
high will aid temperatures in reaching the upper 80s to low 90s
but dew points should be a bit lower in the wake of Monday`s
front plus stronger daytime boundary layer mixing so we are
confidence is lower if heat index values will meet/exceed 95F.
However, confidence increases Wednesday and Thursday, despite
increasing clouds and chances for showers/storms, as dew points
will likely return to very uncomfortable levels. The HeatRisk
values also reach "major" levels both days. Overnight lows will
not provide much relief as high humidity continues and
temperatures struggle to drop under clouds. Depending on the
exact timing of the cold front and upper level shortwave
Thursday/Friday, we should experience relief from the
heat/humidity by the weekend.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
Predominately VFR conditions are expected this afternoon with the
exception being in the vicinity of scattered showers and
thunderstorms. Confidence has decreased in the showers and storms
having a direct impact at the TAF sites and the PROB30 groups have
been removed from the forecasts for this afternoon. Shower and
thunderstorm activity will diminish during the evening hours before
MVFR/IFR stratus builds into the region after 06z. Ceilings should
begin to improve to MVFR/IFR between 14z-16z. Winds throughout the
forecast period are generally expected to be out of the south at
less than 10 knots.

Outlook...

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

&&

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

&&

$$

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