December 12: ORD

Today is December 12th. It's the 347th day of the year. 19 days remain. It's week 50 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 35 and the normal low is 21. The 30-year averages are 36 and 22.

On the warm side, in 1991 the high was the near-record high of 60 with a low of 38. The record high of 61 was set way back in 1877. A year earlier, in 1990, the high was 55 with a low of 35. Two years ago the high was 50 with a low of 38. In 2001 the high was 47 with a low of 38. In 1984 the high was also 47 with a low of 32. Other warm highs were 48 in both 1980 and 1998. Another warm low was 35 in 1996. The record warmest low of 48 was set in 1968. 25 of the last 30 highs were 20s (8), 30s (8) and 40s (9). Two highs were 10s, two highs were 50s and one high was in the 60s.

In looking back through the years to the first December at O'Hare in 1958, the following instances were notable. In 1975 the high was 38 with a low of 35, a three degree spread. In 1974 the high was 35 with a low of 31, a four degree spread. In 1970 the high was 36 with a low of 32, a four degree spread. In 1968 the high was 53 with a low of 48, a five degree spread. That low of 48 was the record warmest low, except that it was recorded at Midway. In 1967 the high was 42 with a low of 36, a six degree spread. In 1966 the high was 28 with a low of 21, a seven degree spread. In 1962 the high was the record coldest high of 10 with the former record low of -7, a very cold day. In 1959 the high was 39 with a low of 34, a five degree spread. In 1958 the high was 12 with a low of 3, another very cold day.

More recently, we had small spreads of five degrees in 1983 (36/31), five degrees in 1996 (40/35) and seven degrees in 1987 (39/32).

On the cold side, in 2000 the high was 15 with the record low of -8, a very cold day. The former record low of -7 occurred in 1962. In 1989 the high was 17 with a low of 5. Three years earlier, in 1986, the high was 21 with a low of 5. Four years before that, in 1982, the high was 23 with a low of 7. In 1995 the high was 24 with a low of 7. Ten years earlier, in 1985, the high was 22 with a low of 9. Other cold lows were 9 in 2005, 10 in 1988 and 10 in 2003. Another cold high was 24 in 2003. The record coldest high of 10 was set in 1962. 19 of the last 30 lows were 20s (9) and 30s (10). That was the warm side. The cold side includes six 0s lows, four 10s lows and one low in the negative 0s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:41 and sunrise is at 7:13. Chicago's twilight begins four minutes earlier and sunrise is three minutes earlier. Sunset is at 16:21 and twilight ends at 16:53. Chicago's sunset and end of twilight times are two minutes earlier. There's a total of 9 hours, 8 minutes of daylight today and 10 hours, 12 minutes between twilights. Tomorrow twilight begins at 6:42 and sunrise is at 7:14. The full Cold moon is today at 10:37. Illumination was 100% at midnight, will be 100% at noon and 99% at midnight tonight. Moonset is at 7:26 and moonrise is at 16:12. Moonset is at 8:30 tomorrow. Moonlight time is 15 hours, 14 minutes today.

Today in 1987 at Rockford, 10.6 inches of snow fell. Remarkably, O'Hare only received a trace of snow from the system.

A sister of mine, Regina, will celebrate a birthday in two days and Bill of Rights day is in three days. Christmas Eve is in 12 days and Christmas Day is in 13 days. -Bernie-