The Great Barrington, MA tornado on Memorial Day 1995 stole most of the weather headlines on May 29 – but a supercell here in Connecticut produced a tornado in Southbury that looked very impressive on radar.
May 29, 1995 Southbury Tornado
- Intensity: F1
- Length/Width: 2.0 Miles/75 Yards
- Damage: $10,000
- Time: 23:23-23:35 UTC
- Towns Impacted: Southbury
- Details: Snapped and uprooted trees, minor structural damage (shingles). Described in Storm Data as “skipping along ridges” in Southbury after touching down in South Britain.
- Hail up to 1″ in diameter occurred farther east of the touchdown.
The Southbury tornado was a beast on radar. The supercell featured a classic hook echo, strong low level gate-to-gate shear (delta-V on the order of 70 knots at 3300ft AGL around the time of tornadogenesis) and a very powerful mid level mesocyclone and bounded weak echo region.
Here is a look at that mid level mesocyclone at 12,000 ft AGL in Southbury about 5 minutes prior to the initial touchdown. The mesocyclone is very tight with rotational velocity >50 knots. You can also see the BEWR coincident with the strong mesocyclone.
This was an impressive storm! The environment was strongly sheared and quite unstable. The 00z sounding from OKX reveals 500 hpa flow of 50 knots out of the west. The 22z ob from DXR shows a 210º wind with a temperature of 69/65. At 20z DXR reached 77/66.
What jumps out on the 00z OKX sounding is the steep lapse rates from 600-850mb. This elevated mixed layer lead to a narrow corridor of very high CAPE – especially given readings like 77/66 as mentioned above ahead of the supercell that formed.
The 600-850mb lapse rate off this OKX sounding is an impressive 8.3C/km! With that juicy/high theta-e air underneath that cap you can bet CAPE values were substantial. 0-6km shear was well in excess of 40 knots which was more than capable of supporting supercells.