Albany, NY WFO Forecast Discussion

Forecast Discussion for ALY NWS Office
FXUS61 KALY 261043

Area Forecast Discussion
National Weather Service Albany NY
643 AM EDT Sat May 26 2018

High pressure building east off the Atlantic coast will bring
very warm conditions to our region through today with
increasing amounts of humidity. Some showers or thunderstorms
are possible over the holiday weekend along with cooler
temperatures as a cold front drops southward across the region.


Leading edge of showers tracking just north of our area and
tending to dry up. Some mid and high clouds extend south into
the Mohawk Valley and southern VT. Based on trends in satellite
and radar data and the latest guidance, the cold front north of
the U.S. Canadian border will make slow progress south through
the day. So, the best chances for considerable cloud cover and
scattered showers and storms would be north of the Mohawk Valley
into southern VT.

Instability is somewhat limited and mostly surface based.
Boundary layer winds and shear are limited as well. There will
be some low level forcing with the wind shift and the cooling at
the surface but thunderstorms should stay below severe limits.

Areas along and south of the Mohawk Valley and southern VT will
see enough sunshine to help temperatures get well into the 80s
with around 90 mid Hudson Valley. Cooler in the 70s in northern
areas with more clouds and the scattered showers and storms.
There is also an upper level feature in the mid Atlantic area
that will support some showers and thunderstorms that should
track toward the mid Hudson Valley and NW CT late this afternoon
and evening.


There is still a good consensus from sources of guidance for the
cold front to push south of our forecast area but part of the
front stalls somewhere around the eastern Catskills, Schoharie
Valley and western Mohawk Valley. Exactly where is uncertain but
western areas could be warmer than the rest of the region both
Sunday and Monday depending on exactly where the front stalls.

The cooler air at the surface will limit instability and
boundary layer winds will still be relatively weak Sunday. Any
showers and thunderstorms would be scattered at best with highs
in the 60s to around 70 but into the 70s in western areas
depending on where the front stalls. The best chances for
thunderstorms Sunday look to be in western areas where any
instability would be the most.

By Monday, the stalled frontal boundary gradually moves east and
north as upper energy tracks east and another cold front drops
south out of Canada. Once again, instability and forcing is
limited, so isolated to scattered showers and storms at best.
Depending on how well the old frontal boundary exits, there
could be some sun and winds could shift from onshore to south
and southwest. That would help boost temperatures Monday solidly
into the 70s most areas. Any lingering showers would end Monday


The period starts out Tuesday with our region under a northwest flow
aloft, with surface high pressure ridging southward from Canada.
This will provide dry conditions and continued warm temperatures.

By Wednesday, the surface high will settle southeastward along the
southern New England coast. This will result in a light southerly
flow developing around the periphery of the high. Will have to
monitor for possible low level stratus clouds Wednesday morning, but
otherwise dry and mostly sunny conditions are expected. On Thursday,
the surface high is forecast to move off shore, but the upper level
ridge axis will still be in place and should allow for dry
conditions to persist. Again, stratus clouds will be possible during
the morning with southerly flow continuing.

We will then need to watch for possible impacts from the remnants of
Alberto starting during the Thursday night/Friday time frame. There
is still considerable uncertainty regarding the track and forward
speed of Alberto once it has been over land for several days. Due to
uncertainty will mention chance pops during this time. PWAT
anomalies could be considerably high, somewhere in the +2 to +3
range. Depending on the eventual track, we could receive moderate to
heavy rainfall. This will be monitored over the next several days.
Please refer to forecasts issued by the National Hurricane Center
for information on Alberto.

Above normal temperatures will persist through the period, as 850 mb
temp anomalies will run about +1 to +2 STDEV into next weekend.


A warm air mass will remain in place today, although a backdoor
cold front will be pushing southward across the region later
this afternoon into this evening. VFR conditions will prevail
for much of the TAF period, although chances for showers and a
few thunderstorms will increase as the cold front moves through.
Will mention mainly VCSH at KGFL/KALB/KPSF this evening to
account for scattered showers/thunder. Coverage expected to be
more sparse at KPOU. Brief deterioration to MVFR/IFR will be
possible within any heavier showers/storms.

Low-level stratus clouds are expected to develop overnight due
to moist easterly flow in wake of the cold front. At this time,
cigs are expected to mainly be in MVFR range.

Winds will be south-southwest around 5-10 kt, becoming northerly
behind the cold front passage.


Sunday Night: Moderate Operational Impact. Scattered SHRA.
Memorial Day: Low Operational Impact. Isolated SHRA.
Monday Night: No Operational Impact. NO SIG WX.
Tuesday: No Operational Impact. NO SIG WX.
Tuesday Night: No Operational Impact. NO SIG WX.
Wednesday: No Operational Impact. NO SIG WX.
Wednesday Night: No Operational Impact. NO SIG WX.
Thursday: Low Operational Impact. Slight Chance of SHRA.


High pressure building east off the Atlantic coast will bring
very warm conditions to our region through today with
increasing amounts of humidity. Some showers or thunderstorms
are possible over the holiday weekend along with cooler
temperatures as a cold front drops southward across the region.

RH values drop to 35 to 55 percent this afternoon and then
increase to 70 to 100 percent tonight. RH values drop to 65 to
80 percent Sunday.

West to southwest winds will be around 15 mph through this
afternoon and shift to east and southeast at around 15 mph by
daybreak Sunday. Winds will be southeast around 15 mph through
the day Sunday.


No hydrologic issues are anticipated over the next few days.

Dry weather is expected to continue through tonight with high
pressure in control. As a result, rivers, streams, lakes, ponds,
reservoirs, brooks, creeks and kills will remain fairly steady
over the next few days.

Our next chance for scattered showers and possible thunderstorms
will be over the holiday weekend. Northern and central areas
will have the best chance of seeing a shower or thunderstorm
through today, with better chances across the remainder of the
area for Sunday into Monday. Rainfall amounts will be highly
variable due to thunderstorm activity and some locations may
stay completely dry.

For details on specific area rivers and lakes, including
observed and forecast river stages and lake elevations, please
visit the Advanced Hydrologic Prediction Service /AHPS/ graphs
on our website.





NWS ALY Office Area Forecast Discussion