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Area forecast discussion 
National Weather Service Albany New York
752 PM EDT Friday Aug 1 2014

Synopsis...
scattered showers and thunderstorms will occur through Tuesday.
Most of the activity will be during the afternoon and evening
hours. The showers and thunderstorms will be mainly the result of
an upper level disturbance across northern Canada which is
associated with a deep trough of low pressure with several spokes
of energy rotating around it. A cold front will swing through on
Tuesday bringing more scattered showers and thunderstorms.

&&

Near term /until 6 am Saturday morning/...
as of 620 PM EDT...scattered convection continues mainly across
the southern third of the forecast area. This is in response to a vorticity maximum
situated across southeast and southern New England New York which
combined with mlmucapes of 1500 j/kg and daytime heating were
enough to produce the convection which has produced some locally
heavy rainfall. The convection is expected to continue for the
next several hours and then slowly dissipate with the loss of
daytime heating. There is also another concern with the ongoing
convection and that is the potential for some urban and poor
drainage flooding due to the lack of flow and slow movement of the
cells. Expect overnight lows to be in the middle 50s to middle 60s.

&&

Short term /6 am Saturday morning through Monday/...
not much improvement is expected during the short term period as
the convection will likely become a little more widespread
Saturday into Sunday as numerous vorticity maximums rotate across the region
around the base of the upper trough with the upper trough axis
expected to cross the region late Sunday and Sunday night. Even by
Monday there will still be some convection as a secondary trough
axis moves across the region. Mlmucapes will rise as high as 2000
j/kg across parts of the region both Saturday and Sunday afternoons
with precipitable waters rising up to 1.5 inches. While the forecast area is not outlooked
for severe thunderstorms during this time frame cannot rule out
getting a few isolated storms that approach severe limits. The
bigger threat looks to be Hydro issues as with little flow in the
atmosphere the storms will be relatively slow moving. Expect highs
on Saturday to be in the 70s to around 80 with lows Saturday night
in the middle 50s to lower 60s. Highs on Sunday are expected to be in
the middle 70s to around 80 with lows Sunday night in the middle 50s to
middle 60s. Highs on Monday are expected to be in the upper 70s to
lower 80s.

&&

Long term /Monday night through Friday/...
much of this time period appears to be transitional...changing from
the relatively stagnant pattern preceding it...as northern stream
energy begins to settle back southeast toward southern Canada and
northern New England. A lead impulse should allow a surface cold front
to settle south and east across the region Tuesday...triggering
scattered showers and thunderstorms. Then...as the main upper level
trough potentially digs further south into southeast Canada and northern
New England...cooling middle levels should support at least isolated to
scattered showers...and perhaps a few thunderstorms...for Wednesday
afternoon...and perhaps again Thursday afternoon...albeit with decreasing
areal coverage. Higher terrain across the southern Adirondacks and
southern Vermont might be favored for this isolated/scattered diurnal
shallow convection for Wed-Thu. High pressure may then build in for
late Thursday into Friday...decreasing the chances for convection.

As for temperatures...Tuesday should be warm and humid ahead of the incoming
surface front...with maximum temperatures reaching at least the Lower/Middle 80s in
valleys...and 75-80 across higher terrain. Even warmer maximum temperatures
could occur should there be sufficient sunshine before any
convection...or any convective debris clouds develop. Maximum temperatures
should gradually cool down for Wed-Fri...initially in the upper 70s
to lower 80s in valleys...and Lower/Middle 70s for higher elevations on
Wednesday...cooling to 75-80 in valleys...and middle 60s to around 70 for
higher elevations by Friday...although even cooler maximum temperatures could
occur. Min temperatures should initially be rather warm...mainly in the 60s
for Monday nt/Tuesday am...then trending down into the 50s for valley
areas...and 45-50 for higher elevations by Wednesday-Friday am...with even
cooler mins possible.

&&

Aviation /00z Saturday through Wednesday/...
an upper level trough will slowly approach from the west
Saturday...as a low pressure system develops along a stalled
frontal boundary across the Atlantic coastline and rides
northeast.

For tonight...high and middle level clouds will be thickening for
kalb/kpsf and kpou...while increasing a bit slower at kgfl. A
period of radiational cooling may promote ground fog formation at
kgfl after 04z/Sat...with occasional IFR visibilities/ceilings possible
through 12z/Sat. Elsewhere...moderate to heavy rainfall occurred
this afternoon at kpou...providing for a very moist boundary
layer. However...temperatures are expected to only cool slightly
overnight due to the expected thickening cloud cover.
So...prospects for fog are not as high as might be expected for
kpou...although some low ceilings could develop after 08z/Sat. At
kpsf...some fog and/or low clouds may also develop after 07z/Sat.
At this time...it appears that kalb should remain VFR overnight.

Any low clouds/fog should burn off by 13z-14z/Sat. However...the low
pressure system to our southeast may bring a period of steady rain
to kpou and kpsf between roughly 13z-17z/Sat...possibly producing
MVFR to IFR vsbys/cigs. Otherwise...the bulk of any showers
associated with the slowly approaching upper level trough should
remain mainly west of the taf sites Saturday. However...will
include vcsh for the afternoon hours...in case some of these
expand or drift further east.

Outlook...

Saturday night: moderate operational impact. Chance of rain showers...tsra.
Sunday: moderate operational impact. Chance of rain showers...tsra.
Sunday night: moderate operational impact. Chance of rain showers...tsra.
Monday: moderate operational impact. Chance of rain showers...tsra.
Monday night: low operational impact. Slight chance of rain showers.
Tuesday: moderate operational impact. Scattered rain showers...tsra.
Tuesday night: low operational impact. Isolated rain showers...tsra.
Wednesday: moderate operational impact. Scattered rain showers...tsra.

&&

Fire weather...
scattered showers and thunderstorms will occur through Tuesday.
Most of the activity will be during the afternoon and evening
hours. The showers and thunderstorms will be mainly the result of
an upper level disturbance across northern Canada which is
associated with a deep trough of low pressure with several spokes
of energy rotating around it. A cold front will swing through on
Tuesday bringing more scattered showers and thunderstorms.

&&

Hydrology...
isolated to scattered rain showers or thunderstorms are possible
today...mainly this afternoon and evening...across southern parts
of the area. Any showers or thunderstorms will be slow moving and
are capable of causing some hydrologic concerns. The main concern
will be for urban and poor drainage flooding.

Over the weekend more humid conditions will be gradually
returning and lasting into early next week. There will be a
continued threat for showers and thunderstorms...locally heavy
downpours could occur...and minor flooding of poor drainage and
urban areas will be possible if thunderstorms repeatedly pass over
the same locations... especially on the weekend into Monday.

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...11
near term...11
short term...11
long term...kl
aviation...kl/wasula
fire weather...11
hydrology...11

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