December 1: ORD

Today is December 1st. It's the 335th day of the year. 30 days remain. It's week 48 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 40 and the normal low is 26. I've calculated the 32-year averages at 40 and 26.

On the warm side, in 1982 the high was 63 with a low of 49 (our only 60s high and only 40s low). In 1998 the high was 57 with a low of 33. Other warm highs were 55 last year and 52 in 1994. The record high of 68 was set in 1970. The record warmest low of 52 occurred back in 1914. Over the last 32 years, 23 highs (72%) have been: 30s (12) and 40s (11). Five highs were in the warmer: 50s (4) and 60s (1). Four highs were in the cold 20s, most recently 29 in 2005. Our most recent 40s high was 41 in 2003. 1982 and 1983 were a big contrast. In 1982, the high was 63 with a low of 49, 23 degrees above normal. Payback occurred the following year as the high was 25 with a low of 18, 11.5 degrees below normal.

In looking back through the years to the first December at O'Hare in 1958, the following instances were notable: in 1976 the high was a cold 24 degrees with a low of 16, a cold day. There was a big 46 degree drop in 1975. In 1975, the high on November 30 was 62 and today's low was 16. In 1974 the high was 38 with a low of 32, a six degree spread. In 1972 the low was a cold 13 degrees. In 1970 the high was 67 with a low of 46, a warm day. 1970 was also the year of the record high. In 1968 the high was 37 with a low of 32, a five degree spread. In 1967 the high was 34 with a low of 27, a seven degree spread. In 1966 the high was 25 with a low of 7, a cold day. In 1964 the high was 24 with a low of 11, a cold day. In 1963 the high was 29 with a cold low of 11, a cold day. In 1962 the high was a warm 64 with a low of 25, a 39 degree spread and warm day. Also in 1962, the high temperature was 64 degrees for three days in a row on 11/30, 12/1 and 12/2. What a treat that was! In 1960 the low was a cold 12 degrees.

More recently, there was a large spread of 39 degrees in 1985 (50/11). There were small spreads of four degrees in 1992 (34/30), five degrees in 1987 (34/29), five degrees in 2000 (36/31), seven degrees in 1986 (42/35), seven degrees in 1997 (41/34) and seven degrees in 2004 (32/25).

In 2006, Rockford received 10.7 inches of snow while 5.8 inches fell at O'Hare.

On the cold side, in 1983 the high was 25 with a low of 18, a seven degree spread. In 1988 the high was 28 with a low of 20. Other cold lows were 11 in 1985 and 13 in 2002. The record low of -6 and record coldest high of 2 were set on the same day way back in 1893. 26 of the last 32 lows (81%) were: 20s (15) and 30s (11). Five lows were in the cold 10s (a.k.a. teens). One low was in the warmer 40s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:31 and sunrise is at 7:02. Sunset is at 16:22 and twilight ends at 16:53. There's a total of 9 hours, 20 minutes of daylight today and 10 hours, 22 minutes between twilights. We are losing a minute or two of daylight per day. Tomorrow twilight begins at 6:32 and sunrise is at 7:03. The moon is waning crescent. Illumination was 24% at midnight, will be 19% at noon and 15% at midnight tonight. Moonrise is at 2:25 this morning. Moonset is at 13:27 this afternoon. Moonrise is at 3:38 tomorrow morning. Moonlight time is 11 hours, 2 minutes which is 43 minutes shorter than yesterday.

Pearl Harbor Day is in six days. Bill of Rights Day is in 14 days. -Bernie-