Alert archive / New York / Mesoscale Discussions in 2026

Mesoscale Discussion 1821

August 2, 20266 counties in New York

The Storm Prediction Center issued this mesoscale discussion at Aug 2, 2026, 12:54 PM EDT for 6 counties in New York. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued: Aug 2, 2026, 12:54 PM EDT (16:54 UTC)
Expired: Aug 2, 2026, 2:30 PM EDT
In force: 96 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 20%

Counties Genesee County, NY, Monroe County, NY, Niagara County, NY, Orleans County, NY, Oswego County, NY, Wayne County, NY

The radar

The Buffalo radar (KBUF), 95 km from the middle of the area, began a volume at 16:54 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.

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 4.9 hours before the alert went out and 94 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 329 J/kg
Mixed-layer CIN: -58 J/kg
Mixed-layer LCL: 910 m above ground
0-6 km bulk shear: 59 kt
0-1 km storm-relative helicity: 168 m²/s²
0-3 km storm-relative helicity: 159 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

As transmitted.

509 
ACUS11 KWNS 021654
SWOMCD
SPC MCD 021654 
NYZ000-021830-

Mesoscale Discussion 1821
NWS Storm Prediction Center Norman OK
1154 AM CDT Sun Aug 02 2026

Areas affected...portions of western NY

Concerning...Severe potential...Watch unlikely 

Valid 021654Z - 021830Z

Probability of Watch Issuance...20 percent

SUMMARY...An isolated risk for damaging wind gusts and perhaps a
tornado will skirt the international border near Lake
Ontario/western New York the next couple hours.

DISCUSSION...A bowing thunderstorm cluster has developed along a
surface boundary near the international border/western NY. The
downstream airmass is relatively cool, but moist, resulting in weak
instability. However, low-level SRH is enhanced along the surface
boundary and in proximity to the larger-scale surface low across the
region. While instability is expected to remain weak, 30-40 kt
effective shear magnitudes will support at least occasional storm
organization. Most of the stronger convection will likely remain
over Lake Ontario and or across the international border. However,
this stronger bowing cluster could skirt the western NY/Lake Ontario
shoreline over the next hour or two, resulting in a low risk for
damaging gusts or perhaps a brief tornado.

..Leitman/Mosier.. 08/02/2026

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...BUF...

LAT...LON   43447943 44107714 44127630 43797586 43427596 43127695
            42907828 42957902 43037934 43447943 

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH

Nearby

Mesoscale Discussions in New York, 2026 Every mesoscale discussion 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.