May 23: ORD

Today is May 23rd. It's the 144th day of the year. 222 days remain.

Unless noted, the following data is based upon observations collected by the National Weather Service, Chicago, at O'Hare International Airport (ORD) between 1979 and 2007. Observations have been official at O'Hare since Jan. 17, 1980.

Before this, Midway International Airport (MDW) was the official station of record from Wed. July 1, 1942 to Thu. Jan. 17, 1980. Before July 1, 1942, records were official at various locations in the city going all the way back to Mon. Oct. 16, 1871. Records before this (back to Sat. Oct. 15, 1870) were lost during the Great Chicago Fire which began on the evening of Sun. Oct. 8, 1871.

According to the National Climatic Data Center (NCDC), the normal high for today is 72 and the normal low is 50.
The 29-year averages are 71 and 50.

On the warm side, last year the high was 89 with a low of 60. In 1991 the high was 82 with a low of 66. In 2000 the high was 81 with a low of 57. Other 80s highs were 82 in 1989, 81 in 2004 and 80 in 1994. The record high of 92 was set in 1977. Other warm lows were 61 in 1981 and 57 in 2002. The record warmest low of 71 was set in 1964. 20 of the 29 highs have been in the 60s (10) and 70s (10).

On the cool side, there were no days of means of 12 degrees or more below normal and no highs after 1988 were below 60 degrees. The cool highs include 55 in 1987, 57 in 1982 and 58 in 1988. The cold lows include 38 in 2006 (one degree above the record low of 37 which was set in 1917), 40 in 1985/1992, 41 in 1997 and 42 in 2003. The record coolest high is 50, set in 1931. 25 of the 29 lows have been in the 40s (15) and 50s (10).

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:52 and sunrise is at 5:25. Sunset is at 20:16 and twilight ends at 20:49. There's a total of 14 hours, 51 minutes of sunlight and 15 hours, 57 minutes between twilights. The moon is waning gibbous with 91% visible at midnight and 88% visible at noon. Moonset is at 7:46 and moonrise is at 23:46. Moonlight time is 8 hours exactly today. The moon was full (full Flower moon) at 21:11 four days ago.

Memorial Day is in three days.

- Bernie -