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Very dry air/strong SW winds power huge temp rises Friday

Temps started out in the 30s over most of the Chicago area this past Friday morning, but with very dry in place (dry air warms much faster than moist air) and strengthening SW winds (advecting warmer air into the area), a huge rise in temperatures ensued – afternoon highs ended up reaching into the mid and upper 70s – a resulting temperature rise of 40-degrees plus at many area airport locations. The greatest increase was 47-degrees at Sterling Rock Falls and Lake Geneva/Burlington in SE Wisconsin, followed closely by a 45-degree rise Janesville, WI, Rockford and Aurora/Sugar Grove. A “normal” daily increase is more on the order of 20-degrees or less…the normal high/low for Oct. 21  for Chicago is 61/44, just a 17-degree range.

Frequency of 70 degree+ days the last third of October (Oct 21-31)

So far, in the last third of October 2022 we have experienced 70-degree+ high temps on the 21st and 22nd, with 70-degree readings forecast to occur Sunday (Oct. 23) and Monday (Oct. 24). Without any additional 70s the remainder of the month, those four 70s, starting with the 21st would put October 2022 in a select company of 20 previous Oct 21-31 periods (out of 151 years – back to 1871) where 4 of more 70-deg temp days were observed in Chicago – 13% of the years or about 1 year in every 10.

Above normal Sunshine so far in October 2022 – first time in 10 years!!

The first 10 days this month saw abundant sunshine, then we experienced much more cloudiness and much less sunshine until sunny skies returned the middle of this week. This recent burst of sunshine has helped boost the total monthly sunshine to two-thirds of possible – much above the normal October 57% of possible sunshine. So we’re well on our way toward an October with above normal sunshine – the first October with above normal sunshine since 2012!