Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Albany New York
645 am EDT Monday Sep 1 2014
high pressure will bring a return to some sunshine and very warm
temperatures today. It will remain humid. Temperatures could turn
even hotter on Tuesday. A cold front will approach the region late
Tuesday into Tuesday evening bringing numerous showers and
thunderstorms. Slightly cooler and noticeably drier air will follow
Near term /until 6 PM this evening/...
as of 645 am EDT...one more update as radar now indicated some weak
returns over mainly the higher terrain to the east of Albany.
Suspect there could be quite a bit of drizzle over the hilltowns and
even a little patchy drizzle in the valleys. We included drizzle
along with the fog (more extensive higher terrain) until 900 am EDT.
Otherwise no changes to the previous update.
After the fog and any stratus Burns off...we will have a partly to
mostly sunny sky. This air mass is warm aloft...and with any
sunshine...temperatures should quickly soar through the 70s...and
crest into the 80s this afternoon...locally middle 80s in the capital
region...upper 80s well south and lower 80s north and west of the
Dewpoints will remain elevated...in the 65-70 range. This will
translate to apparent temperatures (combining the air temperature
and humidity)...pushing into the 90-95 range across most valley
Model soundings indicated instability today...perhaps as high as
1500 j/kg. However...they also indicated a pretty good cap (warming
in the middle levels of the atmosphere)...even to the south. Our latest
hrrr indicated some "popcorn" convection south of the capital region
this afternoon...very little to no convection from Albany northward.
There is the remnants of the front to our south which could focus
convection along with more moisture. We will continue with chance probability of precipitation
for thunderstorms (30-40) well south of the capital region...slight
probability of precipitation (20) in and around the capital region...no probability of precipitation (less than 15
percent) well north of the capital region where the air will be a
A light south or southwest wind will average around 5 miles per hour.
Short term /6 PM this evening through Wednesday night/...
any leftover convection will end shortly after sunset...leaving US
with a rainfree but muggy overnight. More patches or even areas of
fog will form after midnight. Lows will be in the 60s...close to 70
in the Tri-City region.
Tuesday...a south to southwest wind will increase a little ahead of
cold front approaching from the northwest. H850 temperatures look to
ramp up to about +18c. With any morning and midday
sunshine...temperatures look to go even a little higher than
today...80s...to near 90 just south of the capital region. The only
exception will be the Adirondack park where more clouds and
showers/thunderstorms...associated with an advancing cold
front...will keep temperatures held to the upper 70s.
Apparent temperatures on Tuesday afternoon are forecasted to reach
the upper 90s in portions of the middle Hudson Valley...generally lower
to middle most other valley areas...80s over the higher terrain.
The aforementioned cold front (and perhaps a pre-frontal trough)
will advance over most our region during the afternoon and early
evening hours. This front produced quite of bit of thunderstorm wind
damage and some large hail in the middle west.
Showers and thunderstorms will likely develop along or a little
ahead of these features. It does appear the best forcing will
actually lift into Canada as the right entrance region of the upper
level jet moves that way.
Nevertheless there should be plenty of instability...low level
convergence (associated with the front)...and moisture...to generate
showers and storms. An organized line could even form. For
now...since we are not officially outlooked by Storm Prediction Center...we will only
mention possible heavy rainfall with the thunderstorms on Tuesday
since precipitable water values will once again increase to 2 inches or
better...exceeding 70% of normal amounts for early September.
Showers and thunderstorms could linger into Tuesday evening...but at
this point...the front looks to move fairly quickly east and be
replaced by somewhat drier and cooler air. The thunderstorm threat
looks to wane by midnight. Temperatures overnight Tuesday look to
fall back into the middle 50s to the northwest of Albany...60-65
An airmass originating from southern Canada will bring a gusty
northwest breeze which will drop dewpoints back into the 50s on
Wednesday. High temperatures will actually still be slightly above
normal...ranging from the middle 70s to middle 80s...locally around 80 in
Albany. However...with the breeze and lower humidity...it will be
more pleasant outdoors.
A mainly clear night on Wednesday and light wind will allow
temperatures settle back into the 50s across much of our
area...except middle or upper 40s over portions of the Adirondacks and
Long term /Thursday through Sunday/...
the long term period starts out with high pressure in control and
increasingly warm temperatures as a southwesterly flow takes hold on the
western side of a large high pressure that will be sliding off the
coast. Mainly dry weather is forecast with only a slight chance of
showers/thunderstorms later Friday afternoon as a cold approaches from the Great
Lakes. Highs Thursday will be in the upper 70s to middle 80s...and a
couple of degrees warmer on Friday. Lows Thursday night in the middle
50s to lower 60s.
The cold front will move into the region at the start of the weekend
along with the threat of showers/tstms. Some model disagreement as
to how fast this front will move through. The Canadian model is the
fastest of all and actually has the front south and east of the
region by Saturday morning with precipitation ending. European model (ecmwf) lingers the front
over the region through the weekend with a chance of showers/thunderstorms
through much of Sunday. The GFS is in between with the front south
and east of the region by Saturday afternoon with the threat of
showers confined to Friday night and early Saturday. Canadian seems
too fast...so taken a compromise between the GFS and European model (ecmwf) with a
chance of showers forecast Friday night through Saturday
night...then clearing and cooler on Sunday as a large Canadian high
pressure system builds into the region. Lows Friday night will be in
the upper 50s to middle 60s. Highs Saturday in the 70s to lower 80s.
Lows Saturday night in the upper 40s and 50s. Highs Sunday in the
middle 60s to middle 70s.
Aviation /12z Monday through Friday/...
MVFR/IFR conditions will prevail through a couple of hours after
sunrise at the kgfl/kalb/kpsf taf sites as low level moisture and
clearing skies above leads to areas of fog and stratus across the
region. At kpou the clouds will be slower to clear and kpou still
has a light south wind as of 06z...so have only forecast occasional
MVFR fog there through sunrise. After around 13z VFR conditions will
return to all the taf sites. Lingering low level moisture and some
weak instability could result in isolated showers/thunderstorms Monday
afternoon...so have included vcsh in the taf forecasts from around 19z
through 00z Tuesday. For Monday night...expect mainly clear skies and
light winds...so fog formation is likely again. Have already
forecast MVFR fog to form at kgfl and kpsf by around midnight.
Winds will be calm or light and variable through much of the
morning...then becoming south or southwest at 8 kts or less during
the rest of the day...then becoming light and variable again Monday
Late Monday night: moderate operational impact. Fog and stratus.
Tuesday: high operational impact. Likely PM rain showers...tsra.
Tuesday night: moderate operational impact. Chance rain showers...tsra.
Wednesday through friday: no operational impact. No sig weather.
today will feature patches of fog to start the day. A stray shower
or thunderstorm is possible this afternoon...mainly south of
Albany...but that will be exception rather than the rule.
With only a light wind...mainly out of the southwest...relative humidity values
will remain elevated today...only dropping to the 55-65 percent
range. It will be very warm with a good deal of sunshine (once the
fog Burns off).
Look for a full recovery tonight with more fog and relative humidity values near
Tuesday will be very warm once more. Some sunshine should burn the
fog away perhaps a little quicker than today. By afternoon
though...a cold front will approach...likely triggering another
round of showers and thunderstorms...some of which could contain
Drier and slightly cooler air will filter in behind the cold front
late Tuesday night and hold for the remainder of the week.
there were pockets of one inch or more of rainfall...mainly north
and south of the capital region on Sunday. Most areas however
received well under an inch of rainfall. There was little if any
impact on main Stem rivers since we had been dry before this rain
Any showers or thunderstorms today will be widely scattered and
should have no impact on our watershed.
Tuesday could be a different story. We expect numerous showers and
thunderstorms afternoon and evening. Average basin rainfall looks to
be mainly under an inch so once again we do not expect many if any
rises on the rivers. However...rainfall could be locally heavy
producing the usual ponding problems.
Drier weather returns by Wednesday...lasting through the remainder
of the workweek.
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.