December 28: ORD

Today is December 28th. It's the 362nd day of the year. Three days remain. It's week 52 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 31 and the normal low is 17. I've calculated the 32-year averages at 36 and 22.

On the warm side, in 1984 the high was the record high of 69 with the record warmest low of 49. In 2003 the high was 49 with a low of 41. In 1982 the high was 65 with a low of 21, a 44 degree spread. In 2006 the high was 48 with a low of 36. In 1992 the high was 44 with a low of 34. A couple of years later, in 1994, the high was 42 with a low of 34. A couple of years after that, in 1996, the high was 39 with a low of 34, a spread of five degrees. In 2005 the temperatures were the same, a high of 39 with a low of 34, also a spread of just five degrees. Another warmer high was 43 in 1986. Other warm lows were 32 in 1991, 30 in 1987 and 30 three years ago. 16 of the last 32 highs (50%) were 30s. On the warmer side, nine highs (28%) were: 40s (7), 50s (0) and 60s (2). O'Hare's only 50s high was 50 in 1959. On the colder side, seven highs (22%) were: 10s (3) and 20s (4).

In looking back through the years to the first December at O'Hare in 1958, the following instances were notable: in 1977 the low was a cold 5 degrees. In 1976 the high was 23 with a cold low of 0, a cold day. In 1974 the high was 35 with a warm low of 33, a mere two degree spread. In 1969 the high was 32 with a low of 25, a seven degree spread. In 1963 the high was 18 with a low of -4, a cold day. In 1962 the high was 34 with a cold low of 1, a 33 degree spread. In 1961 the high was 10 with a low of -4, a cold day. In 1959 the high was 50 with a low of 34, a warm day. In 1958 the high was a warm 49 degrees with a low of 28, a warm day.

More recently, we had a small spread of four degrees three years ago (high of 34, low of 30). The spreads were five degrees in 1987 (35/30) and in 1991 (37/32). There was a small spread of seven degrees in 1979 (31/24).

On the cold side, in 1983 the high was 19 with a low of -1. A couple of years later, in 1985, the high was 19 with a low of 0. Another cold low was 3 in 1993. Another cold high was 19 in 1988. The record low of -13 was set back in 1924 and the record coldest high of -1 was set way back in 1880. 25 of the last 32 lows (78%) were: 10s (8), 20s (9) and 30s (8). On the colder side, five lows were in the: negative single digits (1) and single digits (4). On the warmer side, two lows were 40s.

Today is a major snow day in O'Hare's history. Back in 1978 , 2.8 inches fell. This was part of 16.8 inches that fell over four days.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:50 and sunrise is at 7:21. Sunset is at 16:29 and twilight ends at 17:00. There's a total of 9 hours, 8 minutes of daylight today and 10 hours, 10 minutes between twilights. We gained a minute of daylight from yesterday. Tomorrow twilight begins at 6:50 and sunrise is at 7:22. The moon reached last quarter last night at 22:18 and is waning crescent. Illumination was 49% at midnight, will be 44% at noon and 38% at midnight tonight. Moonrise is at 0:15 this morning. Moonset is at 11:30 this morning. Moonrise is at 1:28 tomorrow morning. Moonlight time is 11 hours, 15 minutes which is 14 minutes less than yesterday.

New Year's Eve is in three days and New Year's Day is in four days. -Bernie-