Alert archive / New York / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 81, NWS Buffalo, NY

July 21, 2026Jefferson County, Lewis County, Oswego County, New York

NWS Buffalo, NY issued this severe thunderstorm warning at Jul 21, 2026, 1:26 PM EDT for Jefferson County, Lewis County, Oswego County, New York. It was in force for 28 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 21, 2026, 1:26 PM EDT (17:26 UTC)
Expired
Jul 21, 2026, 1:54 PM EDT
In force
28 min
Issued by
NWS Buffalo, NY
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Jefferson County, NY, Lewis County, NY, Oswego County, NY

The radar

The Ft Drum radar (KTYX), 14 km from the middle of the area, began a volume at 17:29 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 5.4 hours before the alert went out and 267 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Buffalo Intl Airport, NY at 12:00Z on 2026-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 300 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Buffalo Intl Airport, NY at 12:00Z on 2026-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 162 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
300 J/kg
Mixed-layer CIN
-122 J/kg
Mixed-layer LCL
1133 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
162 m²/s²
0-3 km storm-relative helicity
153 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7

Open this sounding in Storm Lab

The text

As transmitted.

919 
WUUS51 KBUF 211726
SVRBUF
NYC045-049-075-211830-
/O.NEW.KBUF.SV.W.0081.260721T1726Z-260721T1830Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Buffalo NY
126 PM EDT Tue Jul 21 2026

The National Weather Service in Buffalo has issued a

* Severe Thunderstorm Warning for...
  Central Jefferson County in central New York...
  Northern Lewis County in central New York...
  Northeastern Oswego County in central New York...

* Until 230 PM EDT.

* At 126 PM EDT, a severe thunderstorm was located 8 miles south of
  Barnes Corners, or 16 miles east of Sandy Island Beach State Park,
  moving northeast at 40 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Watertown, Fort Drum, Carthage, West Carthage, Adams, Glen Park,
  Herrings, Adams Center, Barnes Corners, and Pitcairn.

This includes Interstate 81 between exits 134 and 161.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Large hail, damaging wind, and continuous cloud to ground lightning
are occurring with this storm. Move indoors immediately. Lightning is
one of nature's leading killers. Remember, if you can hear thunder,
you are close enough to be struck by lightning.

&&

LAT...LON 4353 7591 4378 7620 4430 7563 4410 7517
      4404 7516
TIME...MOT...LOC 1726Z 226DEG 35KT 4370 7588 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Hitchcock
1 follow-up statement
553 
WWUS51 KBUF 211754
SVSBUF

Severe Weather Statement
National Weather Service Buffalo NY
154 PM EDT Tue Jul 21 2026

NYC045-049-075-211804-
/O.CAN.KBUF.SV.W.0081.000000T0000Z-260721T1830Z/
Jefferson NY-Lewis NY-Oswego NY-
154 PM EDT Tue Jul 21 2026

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL JEFFERSON...NORTHERN
LEWIS AND NORTHEASTERN OSWEGO COUNTIES IS CANCELLED...

The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Buffalo.

&&

LAT...LON 4353 7591 4378 7620 4430 7563 4410 7517
      4404 7516
TIME...MOT...LOC 1749Z 226DEG 35KT 4389 7560 

$$

Hitchcock

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Buffalo, NY wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 21, 1:22 PM EDT, 4 minutes earlier. Its key messages:

  • 1) Scattered strong to severe thunderstorms continue through this evening with strong winds as the main hazard. 2) Cool Wednesday, with a chance of lingering showers ahead of a gradual warm up through the remainder of the week.
Area forecast discussion, Jul 21, 1:22 PM EDT, 4 minutes before
Area Forecast Discussion
National Weather Service Buffalo NY
122 PM EDT Tue Jul 21 2026

.WHAT HAS CHANGED...
Minor changes to the forecast with this update.

&&

.KEY MESSAGES...
1) Scattered strong to severe thunderstorms continue through this
evening with strong winds as the main hazard.

2) Cool Wednesday, with a chance of lingering showers ahead of
a gradual warm up through the remainder of the week.

&&

.DISCUSSION...

Key Message 1...Scattered strong to severe thunderstorms continue
through this evening with strong winds as the main hazard.

Scattered showers and thunderstorms early this afternoon have spread
across the Lake Ontario region on both sides of the international
border associated with a compact shortwave noted on GOES WV imagery
lifting just north of Toronto. This is all while earlier storms
across the Southern Tier outran the axis of strongest instability
leading to a swath of stratiform precipitation lingering.
Regardless, severe thunderstorms were still observed this morning
with gusty winds leading to downed trees and small hail reported.
Clearing skies moving into western NY early this afternoon per GOES
satellite imagery will help potentially refuel the atmosphere for
the next round of strong to severe thunderstorms.

Ongoing development in eastern MI and southwestern ON within an area
of 2000 J/kg of MLCAPE and 40 kt of bulk shear closer to the cold
front will be worth monitoring as it moves east towards western NY
later this afternoon into early this evening. Additionally,
southwestward expansion of the ongoing convection near Toronto along
the prefrontal trough associated with the aforementioned
shortwave will also need close monitoring as atmospheric
destabilization continues. These storms will progress eastward
across western and north-central NY through the afternoon and
evening.

Strong winds and heavy rainfall will continue to be the primary
hazard with these storms. PWAT value reported from the KBUF 12z
sounding was 1.50" and warm cloud depths exceed 10 kft. However,
fast storm motions and line normal motions, as observed with earlier
storms, would limit heavy rainfall durations. Additionally, the
highest DCAPE values remain in southwestern ON and will be less than
what was analyzed earlier across the Niagara Frontier around the
time of severe wind damage reported.

Headed into late this evening, lingering showers and a few rumbles
of thunder may continue until the cold front passes through western
NY around midnight and early Wednesday morning for north-central NY.

Key Message 2...Cool Wednesday, with a chance of lingering
showers ahead of a gradual warm up through the remainder of the
week.

Cooler weather is expected Wednesday as the upper level low begins
to exit to the northeast. With 850mb temps dropping around 6-8 degC,
afternoon highs will struggle to reach 70 degF as most locations
will be around 10 degF below normal for late July. Additionally, a
secondary shortwave will round the backside of the departing low,
supporting scattered showers along with the cooler air aloft and
steep low-level lapse rates extending inland from the lakes under
west-northwest flow. High pressure will begin to build into the
lower Great Lakes late Wednesday through the remainder of the week
leading to drier weather and gradually warming temperatures
back towards slightly above normal this weekend.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Multiple rounds of showers and thunderstorms will continue this
afternoon and into this evening with the passage of both a warm
front lifting north, followed by a cold front sliding east. This
being said, a conglomeration of flight conditions will continue
through this evening, with an improving trend overnight into
Wednesday. From the round of showers that just impacted the western
3 terminals (KIAG, KBUF and KJHW), expect these showers and embedded
thunderstorms continue east into KROC within the hour, and reach
KART a couple of hours later. Another line of showers is on our
western doorstep as of 17Z, which will bring more showers and
thunder early this afternoon. Additional, showers are then expected
late this afternoon and into the evening with the arrival of the
cold front.

This all being said, there is a Slight Risk for Severe Thunderstorms
through this evening, where some of the thunderstorms will be
capable of producing damaging winds, large hail, and torrential
rain. Both visibilities and ceilings restrictions can be possible
at times.

Otherwise, ahead of the cold frontal passage's arrival it will be
breezy, with a 20-30 knot south-southwest wind gusts, especially for
KIAG and KBUF this afternoon.

Outlook...

Wednesday...Restrictions likely with lingering showers/isolated
thunderstorms.

Thursday through Saturday...Mainly VFR.

Sunday...VFR/MVFR with a chance for showers/thunderstorms in the
afternoon.

&&

.MARINE...
Southwest winds gusting around 30 kt over Lake Erie and western Lake
Ontario will continue through this afternoon while winds over
eastern Lake Ontario will veer to the southwest. Showers and
thunderstorms will continue throughout the day with multiple rounds
ahead of a cold frontal passage late tonight. Behind the front,
winds will turn to be out of the west-northwest and increase once
again, especially across Lake Ontario, headed into Wednesday. Small
Craft Advisory continues for Lake Erie through tonight and for
portions of Lake Ontario through Wednesday evening. Calmer waters
are expected late this week into early this weekend as high pressure
builds into the lower Great Lakes.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory until 9 PM EDT this evening for LEZ020.
         Small Craft Advisory until midnight EDT tonight for LEZ040-
         041.
         Small Craft Advisory until 6 AM EDT Thursday for
         LOZ042.
         Small Craft Advisory until 10 AM EDT Thursday for LOZ045.

&&

DISCUSSION...Brothers
AVIATION...EAJ
MARINE...Brothers
Hazardous weather outlook, Jul 21, 2:34 AM EDT, 10 hours 52 minutes before
Hazardous Weather Outlook
National Weather Service Buffalo NY
234 AM EDT Tue Jul 21 2026

NYZ001>008-010>014-019>021-085-220645-
Niagara-Orleans-Monroe-Wayne-Northern Cayuga-Oswego-Jefferson-Lewis-
Northern Erie-Genesee-Wyoming-Livingston-Ontario-Chautauqua-
Cattaraugus-Allegany-Southern Erie-
234 AM EDT Tue Jul 21 2026

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

.DAY ONE...Today and tonight.

Several rounds of showers and scattered thunderstorms are expected
from late morning through evening. A few storms may become severe,
with the primary risk being isolated damaging wind gusts. If a line
of storms develops, a longer lasting corridor of wind damage is
possible. There is a low risk of a few isolated tornadoes and
isolated large hail. Some storms may contain torrential downpours,
with low risk of localized flash flooding.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Hazardous weather is not 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-SLZ022-024-220645-
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-
234 AM EDT Tue Jul 21 2026

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.

Several rounds of showers and scattered thunderstorms are expected
from late morning through evening. A few storms may become severe,
with the primary risk being localized gusty winds and higher waves.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Hazardous weather is not 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

In the hours before

Local storm report, Jul 21, 10:57 AM EDT, 2 hours 29 minutes before
Preliminary Local Storm Report
National Weather Service Buffalo NY
1057 AM EDT Tue Jul 21 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1040 AM     Tstm Wnd Dmg     3 WNW Forestville       42.49N 79.24W
07/21/2026                   Chautauqua         NY   Law Enforcement

            Large tree down in the town of Sheridan.

&&

Hitchcock
Local storm report, Jul 21, 12:26 PM EDT, 1 hour before
Preliminary Local Storm Report
National Weather Service Buffalo NY
1226 PM EDT Tue Jul 21 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1147 AM     Tstm Wnd Dmg     Lockport                43.17N 78.70W
07/21/2026                   Niagara            NY   911 Call Center

            Tree down with wires across roadway.

&&

EAJ

The office that day

Everything else NWS Buffalo, NY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 21, 9:08 AM EDTSevere Thunderstorm WarningBUFChautauqua67 min
Jul 21, 9:47 AM EDTSpecial Marine WarningBUF58 min
Jul 21, 9:58 AM EDTSevere Thunderstorm WarningBUFChautauqua46 min
Jul 21, 11:17 AM EDTSpecial Marine WarningBUF38 min
Jul 21, 11:45 AM EDTSevere Thunderstorm WarningBUFErie, Genesee, Niagara, Orleans29 min
Jul 21, 1:29 PM EDTSpecial Marine WarningBUF61 min
Jul 21, 2:05 PM EDTSevere Thunderstorm WarningBUFErie, Niagara55 min
Jul 21, 2:58 PM EDTFlash Flood WarningBUFErie, Niagara5 hr
Jul 21, 5:32 PM EDTSevere Thunderstorm WarningBUFChautauqua58 min
Jul 21, 5:41 PM EDTBeach Hazards StatementBUFCayuga, Jefferson, Monroe, Niagara, Orleans, Oswego and 1 more32 hr
Jul 21, 5:51 PM EDTSevere Thunderstorm WarningBUFMonroe, Ontario, Wayne54 min
Jul 21, 6:14 PM EDTSevere Thunderstorm WarningBUFGenesee, Livingston, Monroe, Ontario, Wyoming76 min
Jul 21, 7:58 PM EDTSevere Thunderstorm WarningBUFOntario31 min

Nearby

Severe Thunderstorm Warnings in New York, 2026Every severe thunderstorm warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.