238
FXUS61 KALY 270806
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
406 AM EDT Mon May 27 2024

.SYNOPSIS...
A humid air mass will be in place for Memorial Day ahead
of an approaching frontal system, which will allow for widespread
showers and thunderstorms this afternoon, some of which may contain
heavy rainfall and gusty winds.  Mainly drier conditions will return
to the region by the middle of the week, with cooler temperatures as
well, although a stray shower still can`t be ruled out.  It will be
dry and comfortable to end the week, as high pressure returns to the
area.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
As of 406 AM EDT...A storm system will be slowly making its way
from the lower Great Lakes towards Ontario and Quebec for today
into this evening. With a moist southerly flow ahead of this
system, abundant moisture moving into the region will help allow
for a few rounds of precip for today.

Initially, the storm`s warm front will be south of the region
for early this morning. MRMS imagery already shows a band of
precip containing light to moderate rainfall, with even an
embedded rumble of thunder. As this lifts northeast towards the
area, it will start to fall apart, but some showers are
possible, mainly for western and southern areas for around or
shortly after daybreak and into the first part of the morning.
This will help allow our region to enter the storm`s warm
sector. Behind these showers, there should be a rain-free period
for several hours for the late morning or early afternoon.

Although satellite imagery shows fairly widespread clouds
around, a few breaks of sun can`t be ruled out for the late
morning or early afternoon hours. Otherwise, it will stay mostly
cloudy. Southerly winds look gusty today thanks to the strong
pressure gradient in place, with some gusts reaching around 30
mph, especially in north-south valleys than channel the
southerly flow. Temps will surge into the 70s for most valley
areas and it will continue to be fairly muggy with dewpoints in
the 60s.

As a pre-frontal trough ahead towards the area for the afternoon
ahead of the main cold front, at least one band of heavy
showers and thunderstorms look to develop to the west of the
area and move through the region, mainly for late in the day
(after 4pm according to the 06z HRRR). Model soundings shows
PWATs will surge above 1.50" and ensemble guidance suggest PWATs
will reach 1 to 3 STD above normal for this time of year.
Although showers and thunderstorms look progressive, some heavy
downpours are expected and there could be some isolated poor
drainage/urban flood issues around. A rogue flash flood can`t be
ruled out if heavy rainfall repeats over any one location,
although this looks like a low-end threat due to rapid movement
of precip and likelihood that the heaviest batch will be within
one main band ahead of the pre- frontal trough late today.

In addition, there is a threat with this activity for some gusty
winds. While instability will be limited (00z SPC HREF shows
MUCAPE values under 1000 J/kg), there is a lot of shear in
place. 0-6 km bulk shear values will be around 40 kts, with a
lot of this in the 0-1 km layer (about 30 kts or so). It won`t
take a tall storm to bring down some gusty winds, so downed tree
limbs are possible within any heavier convective element. SPC
has a marginal to slight risk for severe weather across western
areas for late today.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
Showers and t-storm will still be ongoing this evening and will
linger into the first part of the overnight, as the storm`s
cold front slowly makes progress from west to east across the
area. CAMs show most of the activity should be done by midnight
to 2 AM or so and the threat for the heaviest showers/thunder is
likely early, as the loss of heating should help keep storms
from staying strong. Otherwise, mostly cloudy skies will
gradually become partly to mostly clear towards daybreak
Tuesday, with temps falling into the mid 50s to mid 60s and
dewpoints starting to fall.

Although it will be a little less humid on Tuesday, temps still
look seasonably mild for most areas, with mid to upper 70s in
valley areas. As the upper level trough approaches, some
additional showers and possibly a rumble of thunder will be
possible for late in the day. Any activity on Tuesday look
fairly scattered and mainly limited to areas west and north of
the Capital Region. While sky cover will start off mainly clear
early in the day, it will become partly to mostly cloudy by
afternoon. Any precip should diminish for Tuesday night with
lows in the 50s (some 40s across the highest terrain).

Temps will be a little cooler for Wed into Wed night with the
upper level trough still overhead. Another disturbance rotating
around the main upper level trough will help initiate a few more
showers, although the best forcing looks to be passing south of
the region. Will continue to go with chance POPs on Wednesday
into Wednesday night for most areas, although any showers look
fairly brief and light. Skies will continue to be partly to
mostly cloudy and dewpoints will remain fairly low and
comfortable in the 40s and 50s. Highs will only be in the 60s to
low 70s with overnight lows mainly in the 40s to low 50s.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
An upper-level trough swinging across the region midweek will exit
eastward on Thursday, with rain showers diminishing from west to
east through the day as drier air arrives in its wake. Heights aloft
begin to rise late Thursday into Friday as high-amplitude upper
ridging builds over the region, bringing a return to dry weather
with clearing skies into the weekend.

Temperatures through the period trend upward each day, with
afternoon highs increasing from upper 50s in high terrain to low 70s
along the Hudson Valley on Thursday to upper 60s near 80 across the
region on Sunday. Overnight lows similarly trend warmer, from
widespread 40s on Thursday night to upper 40s to upper 50s on Sunday
night.

On the far side of the weekend, numerical guidance begins to show
substantial differences in the evolution of the upper ridge, leaving
some potential for rain shower chances late Sunday, although
confidence is low at this lead time.


&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
Through 06Z Tuesday...VFR conditions are expected to trend to
MVFR through the remainder of the overnight period at all
terminals as low stratus at 1-2 kft, already observed at POU,
will spread to ALB/PSF/GFL by 08-10Z Mon as a surface warm front
lifts across the region. Scattered rain showers arriving by
08-10Z Mon will increase in coverage resulting in MVFR vsbys
within a more organized band of showers spreading to the north
and east in the early morning, from 11-13Z through 14-16Z Mon.
IFR cigs are most likely at POU during this period, but are also
possible at other regional terminals through much of the
morning.

Behind the warm frontal passage, conditions may improve, with VFR
vsbys expected and cigs lifting back to MVFR across the region. A
robust cold front will then approach from the west in the early
afternoon, with a period of steady rain expected from 20-21Z Mon to
02-03Z Tue. Within the larger area of rain, a narrower band of
thunderstorms is expected to cross from west to east, reaching
ALB/GFL/POU and the Hudson Valley between 21-24Z Mon and PSF between
22Z Mon-01Z Tue. IFR cigs/vsbys within thunderstorms are expected in
this period, though the worst flying conditions will likely be a
more brief window than is currently identified in PROB30 groups.
Behind the cold front, lingering showers may see continued MVFR
conditions through the reminder of the period, although conditions
may trend toward VFR closer to 06Z Tue.

Continued south to southeast winds are expected through the period.
Speeds of 10 kt or less at all terminals will steadily increase to
10-20 kt by 12Z Mon, with gusts of 10-20 kt beginning after 08Z Mon
and increasing to 20-30 kt after 12Z Mon. Brief strong gusty winds
over 30 kt are possible within thunderstorms during the cold frontal
passage around 21-24Z Mon, before speeds decrease to 5-15 kt after
02-03Z Tue.

Outlook...

Tuesday Night: No Operational Impact. NO SIG WX.
Wednesday: Moderate Operational Impact. Chance of SHRA.
Wednesday Night: Moderate Operational Impact. Chance of SHRA.
Thursday: Moderate Operational Impact. Slight Chance of SHRA.
Thursday Night: No Operational Impact. NO SIG WX.
Friday: Low 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...None.
NY...None.
MA...None.
VT...None.

&&

$$

SYNOPSIS...Frugis
NEAR TERM...Frugis
SHORT TERM...Frugis
LONG TERM...Picard
AVIATION...Picard