July 11: ORD

Today is July 11th. It's the 192nd day of the year. 173 days remain. It's week 28 of the year.

Unless noted, the following data is based upon observations collected by the National Weather Service, Chicago, at O'Hare International Airport (ORD) between November 1978 and last year. ORD has been the official site of record for Chicago since Thursday, January 17, 1980.

According to the National Climatic Data Center (NCDC), the normal high is 83 and the normal low is 63. I've calculated the 31-year averages at 83 and 62.

On the hot side, there were no days of a mean of 11.5 degrees or higher. The warmest day by far was in 1980 when the high was 95 with a low of 72. The record high of 97 and record warmest low of 80 were set on the same day back in 1936. 26 of the last 31 highs (84%) were: 70s (10) and 80s (16). Five highs were in the warmer 90s.

In looking back through the years to the first July at O'Hare in 1959, the following instances were notable: In 1975 today (the 11th) and tomorrow (the 12th) the temperatures were the same: a high of 76 with a low of 56. In 1972 the low was a warm 75. In 1968 the high was 80 with a low of 50, a 30 degree spread. In 1965 the low was a cool 51. In 1963 the high was 88 with a low of 53, a 35 degree spread. In 1961 the high was 86 with a low of 55, a 31 degree spread.

More recently, there were large spreads of: 32 degrees in 1996 (82/50), 30 degrees in 1994 (84/54) and 30 degrees in 1997 (84/54).

On the cool side, there were no days of a mean of 11.5 degrees or more below normal. The coolest low was the record low of 50 set in 1996. The former record low was 51 in 1978. Another cool low was 52 in 1999. The record coolest high of 65 occurred way back in 1873. 24 of the last 31 lows (77%) were 60s. Six lows were in the cooler 50s. One low was in the warmer 70s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight began at 4:53 and sunrise was at 5:27. Sunset is at 20:30 and twilight ends at 21:04. There's a total of 15 hours, 3 minutes of daylight today and 16 hours, 11 minutes between twilights. Tomorrow twilight begins at 4:54 and sunrise is at 5:28. The moon is new today at 14:40. Illumination was 0% at midnight, will be 0% at noon and 0% at midnight tonight. Moonrise was at 5:08 this morning. Moonset is at 20:31 and moonrise is at 6:25 tomorrow morning. Moonlight time is 15 hours, 23 minutes which is 26 minutes shorter than yesterday (it peaked at 15:56).

NASCAR was at my home track, the Chicagoland Speedway (Joliet, IL) last night. In the Sprint Cup/LifeLock 400, David Reutimann won. Parent's Day is in two weeks. - Bernie -