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FXUS61 KBUF 152042
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Area Forecast Discussion
National Weather Service Buffalo NY
442 PM EDT Sat Jun 15 2024

.SYNOPSIS...
High pressure will build over the eastern Great Lakes tonight before
moving off the New England coast Sunday, bringing a continuation of
dry weather to the region. It will be cool tonight, then a warming
trend begins Sunday. Heat and humidity will build Monday, and last
through much of next week with high temperatures in the 90s and
dangerous heat index values peaking in the upper 90s to low 100s
Tuesday and Wednesday.

&&

.NEAR TERM /THROUGH SUNDAY/...
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Visible satellite imagery late this afternoon showing diurnal cu
fields along and inland of lake breeze circulations starting to
shrink a bit as mixing continues to deplete what lingering low level
moisture there is left. As we lose daytime heating toward early
evening and thus diurnal mixing ceases, any lingering diurnal cu
will dissipate, leaving mainly clear skies later this evening.
Temperatures will mainly range from the mid 60s to around 70 through
sunset.

Tonight, surface high pressure centered over Lake Huron will settle
across the eastern Great Lakes. Light winds, clear skies, and a
cool/dry airmass will allow for good radiational cooling. Lows will
drop back into the 40s for inland locations, with lower 50s along
the immediate lakeshores. Some of the coolest locations in the North
Country may even drop into the upper 30s.

Sunday, surface high pressure will drift east across New England,
then off the east coast by evening. Increasing warm advection in the
wake of the departing high will bring some periods of high cirrus,
but these should remain thin enough to still yield a mostly sunny
day. Temperatures will begin to increase, with highs in the low to
mid 80s for Western NY, and 70s for the North Country.
-- End Changed Discussion --

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
...Dangerous Heat Wave Will Begin to Impact the Region...

Broad mid-level ridging centered across the Great Lakes Sunday will
continue its eastward progression into the eastern Great Lakes and
eventually center over the Northeast by Tuesday. Meanwhile within
the ridging, a shortwave trough will ride the top of the ridge
Sunday into Monday well to the north of the region. While this
shortwave trough indicates some active weather Sunday night, its
placement well to the north should keep most of the activity to the
north of the area though a few showers may be possible across the
North Country. Despite the ridge and surface high in place across
the Northeast, there is a slight chance for the potential for
diurnally driven convection.

Outside of this, deep southerly flow will advect in warmth and
moisture from the Gulf of Mexico initiating the heat wave for the
middle portion of the week. Of the first two days of the new work
week, Monday will be cooler. Though this being said, it will still
be quite sultry with highs in the upper 80s to low 90s across much
of the region and low to mid 90s across the climatologically warmer
spots of the Genesee Valley. Given not much respite in temperatures
Monday night (lows ranging in the upper 60s to low 70s),
temperatures Tuesday will soar into the 90s, with the typically hot
spots of the Genesee Valley approaching the 100 degree mark.

The hot high temperatures combined with the humidity will create
heat index values Monday to range in the upper 80s to mid 90s,
whereas Tuesday will see heat index values between 95 and 105
degrees. With such hot conditions, please remember to drink plenty
of fluids, stay in cooler areas (air conditioned or shaded), and
wear light loose clothing to help remain cool and avoid heat illness!

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
...Dangerous Heat Wave Will Continue For The Region...

An anomalously strong upper level ridge will be centered from the
Mid-Atlantic region to New England region Wednesday. This location
is slightly southeast from previous forecasts where the potential
6000 meter high would be centered closer to western and north
central NY. This southeast shift may impact the chance for showers
and thunderstorms but it will still be hot and humid. The latest
NAEFS shows the strength of the 500mb high will reach the maximum
for all hours for this time of year across the forecast area. Deep
southerly flow will cause hot, humid air to surge across the eastern
CONUS. A weak upper level trough will move from the Canadian Rockies
to James Bay through the end of the work week and the strong ridge
will move south, centering over the Mid-Atlantic region. The ridge
will slowly weaken over the Mid-Atlantic region with zonal flow
across the forecast area Friday through Saturday.

It will be HOT AND HUMID across the forecast area Wednesday through
Saturday. High temperatures will likely peak Wednesday with HIGHS in
the mid to upper 90s and LOWS in the mid 70s Wednesday night, before
high and lows fall a few degrees each day (Thursday, Friday, and
Saturday.) IMPORTANT: While a lot of attention is on the heat and
humidity during the day, low temperatures in the 70s will give
little relief to this heat wave.

In regards to the probability of precipitation, the slight southeast
shift in the ridge Wednesday increases the chance (although still
low) for the potential of thunderstorm complexes entering the
forecast area Wednesday. As the flow becomes zonal, there remains
the low chance of additional showers and thunderstorms entering the
region. Confidence is very low this far out. Daytime heating with
dewpoints in the upper 60s to low 70s will create surface based
instability every day. The strong ridge will suppress a lot of
activity, with low (15-30%) chances across inland areas and along
lake breeze boundaries.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
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VFR will prevail through Sunday as high pressure drifts from the
eastern Great Lakes into New England. Diurnal cu along and
inland of lake breeze circulations late this afternoon, with
bases in the 4-6kft range, will dissipate by early evening. A
few periods of high/thin cirrus will then cross the region
tonight through Sunday. Winds will be relatively light through
the period.

Outlook...

Monday...VFR.
Tuesday through Thursday...VFR, but a slight chance for afternoon
thunderstorms inland from the lakes.
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&&

.MARINE...
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Winds and waves will remain below Small Craft Advisory criteria
through the rest of the weekend. Easterly winds will increase
Sunday, especially on the central and western portions of Lake
Ontario where it will become quite choppy.

Winds will then generally be light Monday through much of next week
as high pressure anchors over the Ohio Valley and New England.
-- End Changed Discussion --

&&

.CLIMATE...
A prolonged period of heat is expected for our region, starting
Monday June 17th. Below are record high temperatures for our three
main climate sites:

...Buffalo...

...Date.....Record Maximum (F)...Record warm Minimum (F)...

...June 17........94/1994............73/2006
...June 18........95/1994............73/2006
...June 19........90/2001............73/1919
...June 20........92/1995............73/2012


...Rochester...

...Date.....Record Maximum (F)...Record warm Minimum (F)...

...June 17........94/1994............70/1994
...June 18........97/1957............72/2018
...June 19........95/2001............72/1919
...June 20........95/1953............72/1923


...Watertown...

...Date.....Record Maximum (F)...Record warm Minimum (F)...

...June 17........89/1994............68/1949
...June 18........91/1957............70/1992
...June 19........91/2007............70/1949
...June 20........90/1971............71/2012

Temperature records for Buffalo and Rochester date back to 1871.
Temperature records for Watertown date back to 1949.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.

&&

$$

SYNOPSIS...Hitchcock
NEAR TERM...Hitchcock/JM
SHORT TERM...EAJ
LONG TERM...HSK
AVIATION...Hitchcock/JM
MARINE...Hitchcock/JM
CLIMATE...Thomas