ENOUGH TO STOP THE CUBS. Tornado alerts are not unknown in Chicago.

Yowza ... we had massive thunderstorms here last night, with the tornado sirens going for the first time I've ever heard them in Chicago. We actually grabbed the cat and the laptops and the firebox with the valuables and headed for the basement, where we poured pitchers of water and waited. Thankfully it all came to naught and was over quickly; within half an hour we were back upstairs watching the Weather Channel.

To the west, it looked like a replay of last month's derecho, this time with radar echoes that suggested a tornado heading east along the Milwaukee Road's Illinois Division from Stillman Valley to Elgin. Today's commentary from the university meteorologist included links to archived radar animations from Davenport and Romeoville (these are animated .gif files that load slowly -- open the links in new windows) and this observation.

Notice the "comma head" self-developing low pressure over northern DeKalb county with the system as it passed through our area. I'm still surprised there wasn't a confirmed tornado along route 72 or just south of there here in the county...

The forecast discussion included recognition of the hazards of long-term predictions.

The 16 day model forecasts (I know, take this with a grain of salt) at least show a jet stream pattern NOT conducive to any major heat through the third week of August, and that takes out what is climatologically the warmest part of the year. With only several 90 degree highs under our belt so far, and with 21 days of 90 degree highs or higher for the year being average, it's becoming safe to say that our somewhat above average summer temperature forecast will go down in flames.

Set aside the mixed metaphor (daytime highs in the 70s send the forecast "down in flames") and contemplate the difficulties of separating climate change signal from seasonal weather noise.