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fxus61 kaly 280535 
afdaly

Area forecast discussion
National Weather Service Albany New York
135 am EDT Wed Jun 28 2017

Synopsis...
in the wake of a strong upper level disturbance and cold front, a
cool air mass will be over the region tonight, as high pressure
builds in from the mid Atlantic region. Generally fair weather is
expected for Wednesday and Wednesday night, although an isolated
shower is possible across portions of the southern Adirondacks and
southern Vermont. A warm front will approach from the Ohio Valley
and Great Lakes region for Thursday into Thursday night, bringing
more showers and thunderstorms. Warm and humid conditions, along
with several rounds of showers and thunderstorms, are expected for
Friday into Saturday.

&&

Near term /until 6 am this morning/...
as of 1242 am EDT...cyclonic flow continues across the forecast
area early this morning with the mid and upper level trough
axis moving into west-cntrl NY, PA, and the mid Atlantic region.
A few showers are continuing over Herkimer and Hamilton
counties with the upper low, and slight chc pops were kept in a
few hours there.

The bigger issue is the development of mist or fog across
portions the upper Hudson Valley, Lake George region into
southern Vermont and the Berkshires due to clearing skies, light to
calm winds and recent wet ground due to the showers and
thunderstorms yesterday. Patchy to areas of fog (locally dense
in a few spots) have been expanded a bit across portions of
western New England, and the Mohawk and Hudson River valley this
morning. Temps have cooled off close to previously forecasted
mins in some locations already in the very cool late June air
mass. The New York mesonet indicates it is 46f already at
Indian Lake in the Adirondacks, Johnstown in the Mohawk Valley
has hit 47f, and the kgfl ASOS has hit 47f. Some mid and upper
40s have already been reached in the eastern Catskills,
Berkshires and southern Vermont. We lowered mins a bit with some
lower 40s over the southern dacks, eastern Catskills, and
southern VT, and mid 40s to lower 50s across the rest of the
fcst area with the skies becoming mostly clear to partly cloudy
towards daybreak.

&&

Short term /6 am this morning through Friday night/...
Wednesday-Wednesday night, generally fair through the period.
However, lingering instability and weak disturbances passing
southeast across northern New England could allow isolated
showers to develop in the afternoon across portions of the
southern Adirondacks and southern Vermont. It will be a bit warmer
Wednesday with highs mainly in the 70s, and lows Wed night in
the 50s.

Thursday-Friday night, the leading edge of much warmer/more
humid air will approach Thursday afternoon, as a strong low
level jet impinges on the region. Strong forcing may produce an
upstream mesoscale convective system across the northern Great Lakes early Thursday
morning which may then track east/southeast into at least
northern areas for later Thursday morning into the afternoon.
Most likely, this mesoscale convective system should be weakening as it tracks into the
southern Adirondacks and Mohawk Valley region, feeding mainly
from elevated instability from central/western New York state. Have
indicated highest pops for areas north of I-90, with only
chances to the south. There remains considerable uncertainty
regarding the exact placement of the incoming surface warm front
for later Thursday into Thursday night. If there is some form
of an mesoscale convective system across northern areas, then the warm front may be much
slower to lift northward into our region. If there is much less
activity, then the warm front may have a better chance to lift
north and east through the region. Have trended a closer to the
cooler side of guidance, with the expectation of at least some
form of showers/storms impacting northern and central areas
Thursday afternoon. Either way, it appears that multiple rounds
of showers/thunderstorms will impact the region Thursday night
into Friday as some form of a low level thermal gradient remains
nearby. There could be some potential for strong/severe
thunderstorms with 0-6 km bulk shear remaining 30-40 kt, and
possible sb CAPES exceeding 1500 j/kg across at least portions
of the region Friday.

&&

Long term /Saturday through Tuesday/...
the long term period is expected to start out unsettled as a series
of frontal boundaries are expected to impact the forecast area. The
unsettled weather is expected to continue into early next week as a
frontal boundary stalls to our south and east.

Showers along with scattered thunderstorms are expected Saturday and
Sunday as a low pressure system and a cold front move across the
region. Highs on Saturday will be in the mid 70s to upper 80s with
lows Saturday night in the 60s to around 70 and highs on Sunday in
the upper 60s to upper 80s.

Sunday night through Tuesday...the frontal boundary will stall south
and east of the region as an area of low pressure moves
northeastward along the frontal boundary. This will keep unsettled
weather across the region into the middle of next week. Expect lows
Sunday night to be in the mid 50s to mid 60s with highs on Monday in
the upper 60s to mid 80s, lows Monday night in the mid 50s to mid
60s, and highs on Tuesday in the upper 60s to lower 80s.

Overall expect temperatures to average close to normal with
precipitation above normal.

&&

Aviation /06z Wednesday through Sunday/...
a batch of broken mid level clouds is moving across much of the
area, which will tend to limit fog development. However, kpsf
has already seen thick fog formation occur and is socked in
with LIFR conditions. Thinking this will continue through the
rest of the night, with improvement after sunrise. Clouds may
tend to move east of the region just before sunrise, which is
when kgfl will have the best chance of seeing some fog. Will
mention a tempo for IFR fog between 08z-11z. Otherwise, some fog
in the vicinity of kalb is possible along the Mohawk River, but
not expected to move over the terminal. Skies are clearer
towards kpou, so occasional MVFR vsby will be possible in br
just before sunrise.

From around 12z Onward, VFR conditions are expected with just
few-sct cumulus and high level cirrus clouds around today. An
isolated shower will be possible near kgfl, but chances too
remote to include in the taf at this time.

Winds will be variable less than 5 kt initially early this
morning, becoming westerly and increasing to around 8-12 kt by
late this morning. Some gusts near 20 kt will occur at
kalb/kpsf, especially this afternoon.

Outlook...

Wednesday night: no operational impact. No sig weather.
Thursday: moderate operational impact. Breezy chance of rain showers...tsra.
Thursday night: high operational impact. Likely rain showers...tsra.
Friday: high operational impact. Likely rain showers...tsra.
Friday night: moderate operational impact. Chance of rain showers...tsra.
Saturday: high operational impact. Definite rain showers...tsra.
Saturday night: high operational impact. Likely rain showers.
Sunday: moderate operational impact. Chance of rain showers...tsra.

&&

Fire weather...
in the wake of a strong upper level disturbance and cold front, a
cool air mass will be over the region tonight, as high pressure
builds in from the mid Atlantic region. Generally fair weather is
expected for Wednesday and Wednesday night, although an isolated
shower is possible across portions of the southern Adirondacks and
southern Vermont. A warm front will approach from the Ohio Valley
and Great Lakes region for Thursday into Thursday night, bringing
more showers and thunderstorms. Warm and humid conditions, along
with several rounds of showers and thunderstorms, are expected for
Friday into Saturday.

The relative humidity values will recover close to 100 percent tonight. Expect
minimum relative humidity values of 35 to 55 percent on Wednesday.

The winds will from the southwest to northwest at 5 to 15 mph
today. The winds will be from the southwest to west at 10 mph or
less tonight, and then increase from the west to northwest at
10 to 15 mph with some gusts to 20-25 mph on Wednesday.

Winds will be stronger, and variable in direction in and
near any thunderstorms.

&&

Hydrology...
no widespread hydrological problems are anticipated over the
next several days. Scattered to numerous showers and thunderstorms
are expected through the early evening hours, as a cold front
and upper low impact the region. Basin average rainfall amounts
will generally be a tenth to a third of an inch in some
locations.

A brief period of mainly dry weather is expected most of
Wednesday into Wednesday night with ridging briefly building in from
the south. An active pattern sets up Thursday into the weekend
with showers and thunderstorms possible with increasing humidity
levels. Rainfall amounts will vary based on where any
convection occurs. The most widespread potential rainfall is
expected Thursday and Saturday. Rainfall amounts Thursday-Thursday night
may range from a quarter of an inch to an inch with some locally
higher amounts in thunderstorms. The higher totals right now may
be across the northern basins of the hsa.

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...kl/wasula
near term...wasula
short term...kl

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