November 10: ORD

Today is November 10th. It's the 314th day of the year. 51 days remain. It's week 45 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 50 and the normal low is 35. I've calculated the 32-year averages at 50 and 33.

On the warm side, in 1999 the high was 69 with a low of 47. Five years later, in 2004, the high was 62 (our most recent 60s high) with a low of 47. Other warm highs were 64 in 1998, 63 in 1978, 62 in 1982 and 62 in 2002. Another warm low was 48 in 1992. The record high of 71 and record warmest low of 49 were set on the same day in 1949. 23 of the last 32 highs (72%) have been: 40s (10) and 50s (13). Six highs were in the warmer 60s. Three highs were in the cold 30s.

Yesterday's high of 69 and low of 40 placed it as 6th warmest (in the top 18% of the 33 years I've been keeping data on). Yesterday, some locations hit the 70s: Kankakee and Joliet reached 73, Romeoville and Rockford hit 72, Aurora: 71 and Elgin: 70. Other locations just missed 70: Midway, O'Hare, West Chicago and DeKalb hit 69. McHenry had a high of 68. Northerly Island (in Chicago) reached only 63 because of a breeze off Lake Michigan. However, it's low was only 51 because of it's proximity to the water.

In looking back through the years to the first November at O'Hare in 1958, the following instances were notable: in 1977 the high was 39 with a low of 34, a five degree spread. In 1975 the high was a warm 68 with a low of 38, a 30 degree spread. In 1974 the high was 50 with a low of 46, a four degree spread. In 1973 the high was 41 with a cold low of 18, a cool day. In 1972 the high was 45 with a low of 41, a four degree spread. In 1969 the high was 46 with a low of 41, a five degree spread. In 1960 the high was a cool 37 with a low of 24, a cold day. In 1959 the high was a warm 63 degrees.

More recently, there were no large spreads. There were small spreads of three degrees in 1992 (51/48) and four degrees in 1985 (40/36).

On the cool side, in 1996 the high was 31 with a low of 24, a seven degree spread. In 1979 the high was 34 with a low of 22. In 1986 the high was 42 with the record low of 18. Another cold low was 20 in 1991. The record coldest high of 28 occurred in 1926. 24 of the last 32 lows (75%) were: 20s (11) and 30s (13). One low was in the cold 10s. Seven lows were in the warmer 40s. Temperatures two years ago (in 2008) and in 1991 had means of 32.5 degrees, 9.5 degrees below normal. Two years ago the high was 39 (our third 30s high) with a low of 26. In 1991 the high was 45 with a low of 20, just two degrees above the record.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:08 and sunrise is at 6:38. Sunset is at 16:36 and twilight ends at 17:06. There's a total of 9 hours, 58 minutes of daylight today and 10 hours, 58 minutes between twilights. We are losing two or three minutes of daylight a day. Tomorrow twilight begins at 6:09 and sunrise is at 6:39. The moon is waxing crescent. Illumination was 19% at midnight, will be 23% at noon and 27% at midnight tonight. Moonrise is at 11:03 this morning. Moonset is at 20:37 tonight. Moonrise is at 11:39 tomorrow morning. Moonlight time is 9 hours, 34 minutes which is 20 minutes longer than yesterday.

Veteran's Day is tomorrow. Thanksgiving is in 15 days. -Bernie-