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fxus61 kaly 282241 
afdaly

Area forecast discussion
National Weather Service Albany New York
641 PM EDT Fri Apr 28 2017

Synopsis...
as high pressure departs, a cold front will impact the region late
tonight into tomorrow morning with scattered showers and isolated
thunderstorms. It will remain mild tomorrow, but cooler weather will
return on Sunday, as the boundary lifts back northward as a warm
front with some additional rainfall. Milder temperatures will
return on Monday, but some additional showers and thunderstorms will
occur late Monday into Monday night as the storm's cold front passes
through the area.

&&

Near term /until 6 am Saturday morning/...
as of 640 PM EDT...with an approaching upper level trough over
The Rockies and northern plains and an upper level ridge just
off the southeast coast, broad southwest flow was in place over
the region. At the surface, weak high pressure was in control
behind a cold front which has pushed through the region.

Although skies are currently fairly clear, the fast southwest
flow should allow for some increasing clouds during the evening
hours, as mid and high level clouds over the Ohio Valley spread
towards the area.

Yet another cold front will be heading towards the area, as a
surface front of the leading edge of the approaching upper level
trough starts to move eastward. It should be dry through at
least midnight, afterward, there will be a threat for some
showers and embedded isolated thunderstorms. Looking at the
latest 18z 3km hrrr, the highest chance of seeing a shower or
tstorm will be for areas south of the capital region.
Instability will be limited due the overnight timing, but there
some a rumble in a few areas. Still, activity will be fairly
scattered and not all areas will see precipitation overnight.

Overnight lows will range from the upper 40s over the
Adirondacks to the upper 50s across the Mid Hudson valley.

&&

Short term /6 am Saturday morning through Sunday night/...
the surface cold front should be crossing during the morning
hours, with some partial clearing occurring by the afternoon on
Saturday. Temps aloft won't be cooling off just yet, so temps
look to be mild once again on Saturday, with highs in valley
areas reaching the mid to upper 70s. Any additional showers or
T-storms on Saturday afternoon or evening should remain south of
the region, as the front should be passing by our area to the
south and east.

With our area behind the front, cooler weather will start to
build back in for Saturday night. High pressure nosing down from
Canada will allow light north to northeast winds, and with skies
remaining at least partially clear through much of Saturday
night, lows look to fall into the upper 30s to low 50s.

However, the front stalled to the south will start returning as
a warm front for Sunday. Clouds will be increasing once again
from the south as the boundary heads towards the area and it now
looks like it may wind up being fairly cloudy through the entire
day. Although the best forcing and lift will be west of the
area, there could be some light rain will this front as it heads
back northward, especially for western areas. The extent of
clouds and rain showers will have an impact on just how warm
temps can get. Have not gone as cool as the met guidance, but
temps may only wind up reaching the mid 50s to mid 60s. If
rainfall is more widespread, it could be a little cooler.

The front should continue to lift northward into Sunday night.
The threat for steady rainfall looks to diminish, especially
for southern areas by later in the night. However, some spotty
showers or drizzle could still be ongoing, so have continued
chance pops through the overnight hours. Lows look to fall into
the upper 40s for most areas.

&&

Long term /Monday through Friday/...
the extended portion of the forecast continues to look unsettled
with several chances for precipitation and plenty of cloudiness.

For Monday and Monday night...a warm front and then a cold front
will be crossing the region as a complex low pressure system lifts
northeast through the Great Lakes region and into eastern Canada.
Expect precipitation to become more widespread through the period
along with a chance of thunderstorms on Monday. Highs on Monday are
expected to be in the mid 60s to mid 70s with lows Monday night in
the upper 40s to upper 50s.

Tuesday through Thursday...this period does not look overly wet at
this time, however the upper level trough axis will be moving
through the region on Tuesday and Wednesday bringing some scattered
showers which will be followed by a weak ridge of high pressure
Wednesday night and Thursday with drier conditions. Highs Tuesday
are expected to be in the mid 50s to around 70 with highs on
Wednesday in the upper 40s to mid 60s and highs on Thursday in the
mid 50s to mid 60s. Lows Tuesday night are expected to be in the mid
30s to upper 40s with lows Wednesday night in the mid 30s to mid
40s.

Thursday night and Friday...low pressure will be along the eastern
Seaboard and there is a great deal of uncertainty where the low will
head once it reaches the middle Atlantic coast. It does look to be
unsettled and rather cool with lows Thursday night in the upper 30s
to upper 40s and highs on Friday in the 50s to around 60.

&&

Aviation /00z Saturday through Wednesday/...
just a few to scattered clouds above 3000 feet this evening as
slow drying takes place over our region. The weak cold front
that tracked through earlier today will drift north late tonight
and Saturday morning with some intervals of broken clouds
between 2500-3500 feet and visibilities of 4sm-5sm between 06z-
14z and just scattered showers. Indicating prob30 for showers
for that time. After about 15z Saturday, the ceilings should
rise to above 3000 feet as the front builds north of our region.

Winds will be mainly out of the southwest at 10 knots or less
tonight and back to west later Saturday morning.

Outlook...

Saturday night: no operational impact. No sig weather.
Sunday: low operational impact. Slight chance of rain showers.
Sunday night: moderate operational impact. Chance of rain showers...tsra.
Monday: moderate operational impact. Chance of rain showers...tsra.
Monday night: high operational impact. Definite rain showers.
Tuesday: moderate operational impact. Chance of rain showers.
Tuesday night: moderate operational impact. Chance of rain showers.
Wednesday: low operational impact. Slight chance of rain showers.

&&

Fire weather...
a cold front will cross the region late tonight into Saturday
morning with some showers and isolated thunderstorms. Rainfall
will be fairly light and not all areas will see precipitation. Behind
this front, clearing will occur by Saturday afternoon, with relative humidity
values falling to 40 to 50 percent by the late afternoon hours,
with west to southwest winds increasing to 10 to 20 mph.

Relative humidity values will only fall down to 45 to 60 percent on Sunday with
some additional rain showers possible. Light NE winds will
gradually become south at 5 to 10 mph.

&&

Hydrology...
dry weather will continue through this evening, but another
frontal boundary will return the threat for some scattered
showers and isolated thunderstorms between late tonight into
tomorrow morning. Rainfall amounts will be variable with
generally a tenth to a quarter of an inch where the
showers/thunderstorms occur, but basin average amounts shouldn't
be enough to cause any hydrologic issues.

After a brief period of dry weather Saturday afternoon into
Saturday night, the front will return as a warm front for Sunday
into Sunday night. Rainfall amounts will be fairly light once
again, with mainly a tenth of an inch or less.

A stronger cold front will cross through the region later on
Monday into Monday night. This front may allow for some locally
higher rainfall totals due to more widespread showers and
thunderstorms and a more humid air mass. Although no problems
are anticipated on the main Stem rivers (as shown in the mmefs),
high water or poor drainage within urban or poor drainage areas
will be possible.

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.

&&

Aly watches/warnings/advisories...
CT...none.
New York...none.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...frugis
near term...frugis/11

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