Severe Thunderstorms, Excessive Rain and Heat Hazards

A Moderate Risk of severe thunderstorms (level 4 of 5) is in the outlook across portions of the Midwest today. Damaging winds, a few tornadoes and frequent lightning with heavy rainfall are in the forecast. Meanwhile, dangerous heat across the southern Plains into the Great Lakes, mid-Atlantic and Northeast will expand into Friday. Risk for wildfires for the central Rockies and Sacramento Valley. Read More >

Overview

In the wake of a cold front resulting from the remnants of Hurricane Beryl, a convective severe weather threat existed for North-Central, Central, and South-Central PA.

Straight-line wind gusts were the primary impact, though radar-indicated tornadoes/circulations were present over North-Central PA. A mid-level cap (milder air aloft), despite all other severe weather parameters being in place, kept the storms shorter and storms weaker.

Courtesy: NWS SPC

SPC Mesoscale Convective Discussions

MCD #1569

Courtesy: NWS SPC

MCD #1571

Courtesy: NWS SPC

MCD #1573

Courtesy: NWS SPC

Radar
Storm Reports
Environment

Radar


The first line of convection initiated around 11:00 AM EDT (15:00 UTC) roughly 100 miles East of the cold front.	Peak tornadic activity took place around 2:30 PM EDT (18:30 UTC), though most of this occurred in upstate NY.	Near Landisburg, KCCX imagery showed a MARC (Mid-Altitude Reflectivity Convergence) signature indicative of strong downbursts.

Storm Reports

Environment

Figure 1: The strong cold front associated with post-tropical storm Beryl is seen in the 18z surface analysis. The line of convection is indicated as a squall line in this analysis.

Courtesy NWS WPC

Figure 2: The cold front moved Eastward.

Courtesy NWS WPC

Near-storm environment summary.