December 3: ORD

Today is December 3rd. It's the 337th day of the year. 28 days remain. It's week 49 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 39 and the normal low is 25. I've calculated the 32-year averages at 39 and 25.

On the warm side, in 1998 the high was 67 (our most recent 60s high) with the record warmest low of 54. In 1982 the high was 62 with a low of 47. In 1999 the high was 57 with a low of 48. In 2001 the high was 56 (our most recent 50s high) with a low of 41 (our most recent 40s low). In 1994 the high was 54 with a low of 42. The next year, 1995, the high was 57 with a low of 35. The record high of 71 was set in 1970. Another warm high was 54 in 1988. Over the last 32 years, 15 highs (47%) were 30s. 11 highs (34%) were in the warmer: 40s (4), 50s (5) and 60s (2). Six highs (19%) were in the cold: 10s (1) and 20s (5).

In looking back through the years to the first December at O'Hare in 1958, the following instances were notable: in 1977 the high was a cold 27 with a low of 14, a cold day. In 1976 the high was 21 with a low of 9, a cold day. In 1973 the high was 62 with a low of 44, a warm day. In 1970 the high was 67 with a low of 40, a warm day and year of the record high. In 1966 the high was 23 with a low of 2, a cold day. In 1964 the high was 34 with a low of 29, a five degree spread. In 1963 the high was 23 with a low of 8, a cold day. In 1962 the high was a warm 59 with a low of 33, a warm day. In 1961 the high was a warm 62 with a low of 33, a warm day. In 1958 the high was 37 with a low of 31, a six degree spread.

More recently, there were no large spreads. There were small spreads of three degrees in 1997 (38/35) and six degrees in 1986 (35/29).

On the cold side, in 2006 the high was the record coldest high of 15 with a low of 8, a seven degree spread. The former record coldest high of 16 occurred in 1942. Two decades and a year earlier, in 1985, the high was 24 with a low of 5. In 2002 the high was 24 with a low of 14. In 1989 the high was 25 with a low of 15. In 1980 the high was 30 with a low of 10. Another cold low was 13 in 1991. Another cold high was 27 in 1984. The record low of -5 was set in 1940. 22 of the last 32 lows (69%) were: 10s (9) and 20s (13). Two lows were in the cold 0s. Eight lows were in the warmer: 30s (3), 40s (4) and 50s (1). Our most recent 30s low was 35 in 1997.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:33 and sunrise is at 7:05. Sunset is at 16:22 and twilight ends at 16:53. There's a total of 9 hours, 17 minutes of daylight today and 10 hours, 20 minutes between twilights. We are losing a minute or two of daylight per day. Tomorrow twilight begins at 6:34 and sunrise is at 7:06. The moon is waning crescent. Illumination was 8% at midnight, will be 5% at noon and 3% at midnight tonight. Moonrise is at 4:52 this morning. Moonset is at 14:38 this afternoon. Moonrise is at 6:03 tomorrow morning. Moonlight time is 9 hours, 46 minutes which is 36 minutes shorter than yesterday.

Pearl Harbor Day is in four days. Bill of Rights Day is in 12 days. -Bernie-