Tier credit multipliers are actually better. That's why the Ak-Chin one was so unusual.

This one is interesting because it's worth watching if Chicago happens to get a cold spell on January 25.

The average low temperature on January 25 at Midway Airport is 22 degrees, which would make just a 3x RC multiplier.

Here's the weather in January 2018. Scroll down to "Daily Observations": https://www.wunderground.com/history...DW/date/2018-1

It was never below -10.

There were 3 days below zero, which would have qualified for 10x.

There were 9 days in the single digits, which would have qualified for 7x.

There were 4 days in the teens, which would be 5x.

The rest (15 days) were 20 degrees or higher (2x or 3x).

Also, every day after January 17 was 17 degrees or higher, though that was just the weather patterns of that particular year.

However, looking at 2017, the patterns were similar, with the cold weather coming in early January.

The good thing is that this will be easy to predict about 10 days in advance.