Area Forecast Discussion
Issued by NWS Buffalo, NY
FXUS61 KBUF 231856
Area Forecast Discussion
National Weather Service Buffalo NY
256 PM EDT TUE AUG 23 2016
High pressure centered over Maryland will slowly drift east and off
the Mid Atlantic coastline through midweek. This feature will
provide our region with fair and dry weather through midweek... with
a developing southwesterly return flow of warmer air helping to
drive temperatures back to above normal levels. Another cold front
will then ease its way across the region Thursday night along with
another round of showers and thunderstorms... before fair weather
returns in time for next weekend.
.NEAR TERM /THROUGH WEDNESDAY/...
During this period...surface high pressure centered over Maryland
will slowly drift east to the Mid Atlantic coastline. This feature
will maintain fair and dry weather across our region...with mostly
sunny/clear skies only being marred by some diurnal cumulus mainly
south of Lake Ontario and across the North County. Skies will clear
overnight with the loss of daytime heating. Lows tonight will then
drop back into the mid 50s to lower 60s...with somewhat limited
valley fog again forming across the Western Southern Tier tonight.
Wednesday will be another mostly clear day across the region with a
few diurnal cumulus and some high thin clouds approaching western NY
late in the day. As high pressure slides further off the coast this
will allow a steady increase of heat and humidity in the southerly
return flow. 850 mb temperatures will surge to around +17/+18C,
bringing high temperatures mainly in the upper 80s, with some low
90s in the downslope regions of the Genesee valley and northern
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
After a quiet first half of the week, unsettled weather will return
to Western and North-Central New York starting Wednesday night.
Models are continuing to come into better agreement on a vortmax,
currently visible on wv imagery over Arizona, lifting across the
Great Plains and to the Upper Great Lakes by Wednesday. While the
core of this system and bulk of the resultant convection looks to
pass to our north across Ontario province Wednesday night, the
attendant 500mb trough should clip our area, and this along with
ongoing theta-e advection should be enough to keep a chance of
showers and thunderstorms in the forecast.
Aforementioned theta-e advection will strengthen across the forecast
area on Thursday as warm and sticky GOMEX air flowing around the
periphery of the sub-tropical ridge parked over the Southeastern
U.S. makes its way across the Lower Great Lakes. The arrival of this
hot and humid air will set the stage for more widespread showers and
thunderstorms Thursday afternoon into Thursday evening, with pieces
of shortwave energy ejecting out of the Midwest acting as additional
triggers to convection, in addition to the usual array of lakebreeze
and local convergence boundaries. Given the very moist nature of this
airmass, featuring pwats approaching 2.0 inches, localized heavy
downpours will be a threat. This slug of moisture is currently
progged to pass through the area Thursday night into Friday morning,
with pops diminishing Friday morning as a cold front pushes through,
ushering in cooler and much drier air for the weekend...
Regarding temperatures, with the arrival of the previously discussed
GOMEX airmass, we will see the return of sultry, sticky nights to
the region Wednesday and Thursday night, with lows ranging from the
upper 60s to the lower 70s, with warmest areas along the lake plains
and the urban areas. Thursday will be the warmest day of the period,
with highs climbing into the upper 80s, before the arrival of cooler
and drier air from Canada brings more pleasant highs in the upper
70s to lower 80s on Friday.
.LONG TERM /SATURDAY THROUGH MONDAY/...
We can look forward to a beautiful weekend across Western and North
Central New York...as high pressure will be firmly in control. The
fair weather feature will be centered directly over the forecast
area on Saturday...then it will gradually drift east to the Canadian
Maritimes for the second half of the weekend. While this will
encourage a day to day warming trend...dew points will only be in
the 50s to near 60 so it will remain comfortable throughout the
For Monday...the continuing warming trend will be accompanied by a
gradual increase in humidity levels. While the majority of the day
will be rain free...the growing instability of our more humid
airmass will allow for at least the chance for afternoon
thunderstorms...mainly over the Southern Tier and Finger Lakes
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
High pressure drifting from Maryland to the Mid Atlantic coastline
will continue to lead to predominantly VFR conditions across the
region. The only exception to this will be across the Southern
Tier...where valley fog will lead to some areas of IFR/LIFR
overnight tonight, although this may stay just east of JHW like last
night. Another fine flying day with VFR conditions is expected
Thursday...VFR with scattered showers and thunderstorms
becoming more numerous Thursday night...when some MVFR will also
Friday thru Sunday...Mainly VFR.
High pressure will drift from Maryland off the Mid Atlantic
coastline through midweek...while maintaining light to modest winds
and lower waves.
Thursday and Thursday night a cold front will ease its way across the
Lower Lakes. This feature will bring some showers and thunderstorms
to the region...with freshening southwesterlies out in advance of the
front veering to westerly following its passage Thursday night...
then gradually diminishing on Friday as high pressure builds into
the region. Depending upon how much winds and waves increase...small
craft advisories may eventually be needed for some areas Thursday
and Thursday night.