Wind gusts today……………highs today:
Rapidly-deepening surface low pressure strengthening to a powerhouse storm was a big factor in the howling winds today. Very strong +150 mph upper jet streak diving in led to this strengthening. With this deepening, winds at all levels from surface to mid levels increased tremendously. Warm, moist air rapidly moved north as the low-level jet increased to +58 mph (to as high as 90 mph!).
The low-level winds & very strong pressure gradient with the surface low pressure led to the non-t’storm gusts today generally 40-50 mph with a few gusts +50 mph.
The very strong jet winds/dynamics at mid & upper levels led to diffluence & strong lift, while the extreme low-level shear with the high helicity, wind shift south-southwest to west-southwest & +58 mph winds increased the severe threat.
Bits of CAPE (some even surface-based) developed with a few small peeks of sun in Illinois & local temps reaching as high as 60. This buoyancy with the low-level shear/wind fields & forcing, lift & dynamics aloft led to potential isolated brief EF0 tornado potential & isolated severe gust threat.
A couple of t’storm gusts exceeded 50 mph with one power outage, otherwise, any severe weather was just north & northeast of the Tri-State.
It is interesting to note that this low-pressure system was very similar to the November 17, 2013 tornado outbreak system. However, CAPE/instability was lacking today. If not for this, it is highly likely that this would have been a substantial tornado event. I took the parameters today & increased the CAPE to 2000 J/kg & it was nearly identical to the November 2013 outbreak.
SURFACE LOW (DOWN TO 980 MB!):
- VERY STRONG LOW-LEVEL JET & 2. EXTREME LOW-LEVEL HELICITY (SPIN)…………………3. VERY STRONG UPPER JET STREAK……4. MUCAPE UP TO 250 J/KG