Special Weather Statement, NWS Buffalo, NY

Area Forecast Discussion
National Weather Service Buffalo NY
1058 AM EDT Sun Jun 21 2020

.SYNOPSIS...
Summer's heat and humidity will be upon the region today on this
first full day of astronomical summer. There will be scattered
showers and thunderstorms during the afternoon and evening hours,
with greater coverage area of these storms on Monday and Tuesday. A
cold front will ease its way across the eastern Great Lakes region
Tuesday night, bringing slightly cooler but noticeably less humid
conditions for Wednesday.

&&

.NEAR TERM /THROUGH MONDAY/...
Visible satellite imagery this late morning displays the beginnings
of another cumulus field forming over interior locations. Will need
to watch a boundary (originating from last evenings convection over
western OH) drifting up central Lake Erie this morning as this could
serve as a trigger for additional showers and thunderstorms into the
afternoon hours.

For the region scattered showers and thunderstorms will again form
this afternoon and early evening. There remains very little flow up
through about 25K feet so like yesterday the biggest threat will be
localized heavy rain.

Enhanced wording used in grids for the heavy rain threat from
thunderstorms. General coverage should be less due to weak ridging
aloft and convective vortices becoming more concentrated around an
upper level low off the mid Atlantic coast.

Convection will be more widespread on Monday with passing shortwave
that is over the Lower Ohio River Valley this midday Sunday. There
will be slightly better wind flow aloft...that will aid in the
structure and growth of thunderstorms.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
The warm and humid airmass persists through Tuesday night when a
cold front will finally bring some relief to the heat and humidity.

Thus on Tuesday, expect another round of showers and thunderstorms
developing during on lake breeze boundaries before more numerous
storms develop ahead of the approaching cold front. The front slides
across the region Tuesday night through Wednesday morning. Unlike
most of the storms of recent afternoons, these will have higher
potential to produce stronger gusty winds.

Above normal temperatures continue with lows in the mid to upper 60s
Monday night and one last day of mid to upper 80 readings on Tuesday
before temperatures return to more normal readings
Wednesday/Wednesday night.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
Expect drier and less humid conditions through the period though an
upper trough sliding from the Great Lakes to eastern Canada could
lead to a few afternoon showers and thunderstorms each day.

Highs will range from the upper 70s to lower 80s. Lows will be in
mid 50s to low 60s.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
VFR flight conditions are forecast for the region during this TAF
period.

As has been the case the past few days though...there will continue
to be the risk for some afternoon and early evening convection. This
will mainly be for areas south of a line from Buffalo to Rochester.
Any storms that develop this afternoon will once again be very slow
moving and will carry the potential for generating locally heavy
rain.

Outlook...

Monday and Tuesday...Mainly VFR, with possible MVFR in likely
showers and thunderstorms. Patchy fog mainly along the far Southern
Tier will also be possible, forming late at night and lasting into
morning.
Wednesday and Thursday...VFR with a chance for a shower or
thunderstorm.

&&

.MARINE...
Exceptionally weak flow will continue to support gentle to light
winds through Monday along with flat to negligible waves. This will
result in fine recreational boating conditions...although winds may
actually be too light for effective sailing.

While there will be the risk for a late day thunderstorm on Lake
Erie...there will be a notably higher potential for storms on both
lakes on Monday. The storms on Monday will carry minimal risk for
becoming severe...but mariners should nonetheless be wary of special
marine warnings.

Winds will freshen on both lakes ahead of a cold front on Tuesday.
While general conditions should remain below SCA criteria...it will
be unsettled with likelihood for showers and thunderstorms.

&&

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

&&

SYNOPSIS...Thomas
NEAR TERM...RSH/Thomas
SHORT TERM...Levan
LONG TERM...Levan
AVIATION...RSH/Thomas
MARINE...RSH

Hazardous Weather Outlook
National Weather Service Buffalo NY
437 AM EDT Sun Jun 21 2020

NYZ001>008-010>014-019>021-085-220845-
Niagara-Orleans-Monroe-Wayne-Northern Cayuga-Oswego-Jefferson-Lewis-
Northern Erie-Genesee-Wyoming-Livingston-Ontario-Chautauqua-
Cattaraugus-Allegany-Southern Erie-
437 AM EDT Sun Jun 21 2020

This Hazardous Weather Outlook is for western and north central New
York.

.DAY ONE...Today and tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

This product, along with other watches, warnings, advisories, and
statements issued by the National Weather Service office in Buffalo
can be found on the internet at http://www.weather.gov/buf

LEZ020-040-041-LOZ030-042>045-062>065-SLZ022-024-220845-
Upper Niagara River and Buffalo Harbor-
Lake Erie nearshore waters from Ripley to Dunkirk-
Lake Erie nearshore waters from Dunkirk to Buffalo-
Lower Niagara River-
Lake Ontario nearshore waters from the Niagara River to Hamlin Beach-
Lake Ontario nearshore waters from Hamlin Beach to Sodus Bay-
Lake Ontario nearshore waters from Sodus Bay to Mexico Bay-
Lake Ontario nearshore waters from Mexico Bay to the Saint Lawrence
River-
Lake Ontario open waters from the Niagara River to Hamlin Beach-
Lake Ontario open waters from Hamlin Beach to Sodus Bay-
Lake Ontario open waters from Sodus Bay to Mexico Bay-
Lake Ontario open waters from Mexico Bay to the Saint Lawrence River-
Saint Lawrence River from Cape Vincent to Ogdensburg-
Saint Lawrence River from Ogdensburg to Saint Regis-
437 AM EDT Sun Jun 21 2020

This Hazardous Weather Outlook is for the New York waters of Lake
Erie, Lake Ontario, and the Saint Lawrence River.

.DAY ONE...Today and tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

This product, along with other watches, warnings, advisories, and
statements issued by the National Weather Service office in Buffalo
can be found on the internet at http://www.weather.gov/buf

Special Weather Statement
National Weather Service Buffalo NY
132 PM EDT Sun Jun 21 2020

NYZ003-211815-
Monroe-
132 PM EDT Sun Jun 21 2020

...A STRONG THUNDERSTORM WILL AFFECT SOUTH CENTRAL MONROE COUNTY...

At 132 PM EDT, a strong thunderstorm was located over Scottsville, or
near Chili, moving northeast at 15 mph.

Winds in excess of 30 mph and half inch hail are possible with this
storm.

Locations impacted include...
Rochester, Chili, Brighton, Gates-North Gates, Henrietta,
Scottsville, Martin, Garbutt and Industry.

This includes the following highways...
 Interstate 390 near exit 12.
 Interstate 90 near exit 46.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

LAT...LON 4303 7785 4318 7774 4305 7757 4299 7775
      4299 7778
TIME...MOT...LOC 1732Z 225DEG 11KT 4305 7777

JLA