September 16: ORD

Today is September 16th. It's the 260th day of the year. 106 days remain. It's week 38 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. Observations have been official at O'Hare since Thursday, January 17, 1980.

According to the National Climatic Data Center (NCDC), the normal high is 74 and the normal low is 54. The 29-year averages are 72 and 53.

On the warm side, in 1992 the high was 84 with a low of 70. In 1997 the high was 85 with a low of 65. In 1994 the high was 86 with a low of 63. In 1995 the high was 85 with a low of 61. The record high of 92 was set in 1955 and the record warmest low of 72 was set in 1907. Another warm high was 82 in 2003. Other warm lows were 66 in both 1987 and 1998. There have been 14 highs in the 70s, eight highs in the 60s and five highs in the 80s. Four of the six years from 1992-97 were warm days.

The biggest difference between a daily high and low was 34 degrees in 1985 (high of 76, low of 42). In 2003 the difference was 32 degrees (82/50). In 1997 the difference was 30 degrees (77/47).

On the cool side, in 1984 the high was 64 with the record low of 37. In 1981 the high was 59 (the runner-up earliest 50s high of fall) with a low of 46. In 1982 the high was 61 with a low of 47. In 1993 the high was 59 with a low of 51. In 2000 the high was 67 with a low of 44. The record coolest high of 56 was set in 1959. 22 of the last 29 lows have been in the 40s (11) and 50s (11).

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:07 and sunrise is at 6:35. Sunset is at 19:00 and twilight ends at 19:28. Twilight begins tomorrow at 6:08 and sunrise is at 6:36. There's a total of 12 hours, 25 minutes of daylight today and 13 hours, 21 minutes between twilights. The moon reached full Harvest yesterday at 4:13. Illumination was 99% at midnight, will be 98% at noon and 96% at midnight tonight. Moonset is at 8:02 this morning. Moonrise is at 19:22 tonight and moonset is at 9:16 tomorrow. Moonlight time is 12 hours, 40 minutes today.

Constitution Day, also known as Citizenship day, is tomorrow. This is a newer holiday, having been enacted by Congress just four years ago. The website "www.patriotism.org" says that Constitution Day is "a birthday for our country and it serves as a means for American citizens to express their pride in their citizenship. Constitution Day also designates a time to honor the Constitution of America and learn more about the famous piece of legislation." -Bernie-