Jul 7, 2021
A nearly stationary boundary just south of Lake Ontario divided a moist unstable air mass from a much cooler one. Instability was generating a CAPE of around 2000 J/Kg south of the boundary by late afternoon, but wind shear was limited with 700 hPa winds only around 20 knots. Some pulse storms began to develop by late afternoon, mainly out of our area. A convective wave approached from the Ohio Valley and passed just to our south through the evening. This likely enhanced wind shear, especially i
Source: NOAA National Weather Service Storm Events Database (event 976376). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Allegany County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.