January 21: ORD

Today is January 21st. It's the 21st day of the year. 344 days remain. It's week 3 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 29 and the normal low is 14. The 30-year averages are 30 and 16.

On the warm side, in 1986 the high was 54 with a low of 30. In 1999 the high was 41 with a low of 32. Six years earlier, in 1993, the high was 38 with a low of 33, a five degree spread. Four years later, in 1997, the high was 45 with a low of 24. Other warm lows were 29 in 1998, 27 in 1983 and 26 in 2007. The record high of 62 was set back in 1906 and the record warmest low of 43 was set back in 1916. 21 of the last 30 highs were: 20s (8) and 30s (13). On the warmer side, three highs were 40s and one was in the 50s. On the colder side, four highs were in the 10s and one was in the single digits.

In looking back through the years to the first January at O'Hare in 1959, the following instances were notable. In 1976 the high was 26 with a low of 19, a seven degree spread. In 1974 the high was 37 with a low of 35, a two degree spread. In 1970 the high was 5 with a low of -11, a cold day (at Midway). In 1969 the high was 40 with a low of 36, a four degree spread. In 1967 the high was 50 with a low of 35, a bonus 50s day. In 1966 the high was 30 with a low of 25, a five degree spread. In 1964 the high was 50 with a low of 35, a bonus 50s day. In 1963 the high was 11 with a low of -17, another cold day.

More recently, we had small spreads of three degrees in 1998 (32/29) and 2007 (29/26). The spreads were five degrees in 1995 (26/21), six degrees in 1988 (31/25), seven degrees in 1981 (32/25) and seven degrees in 2005 (24/17).

On the cold side, in 1984 the high was 6 with the record low of -22. In 2000 the high was 13 with a low of -3. In 1985 the high was 18 with a low of -6. In 1994 the high was 21 with a low of -5. Three years earlier, in 1991, the high was 17 with a low of 3. The record coldest high of -4 was set way back in 1883. 19 of the last 30 lows have been: 10s (7) and 20s (12). On the colder side, eight lows were: negative 20s (1), negative single digits (3) and single digits (4). Three lows were in the warmer 30s. There have been no lows in the negative 10s.

Today is a major day in O'Hare's snow history. In 2005, 4.8 inches fell. This was the second day of a four day, 12.7 inch period of snow. Along with the 9.8 inches that fell earlier on January 4-6, this comprised 22.5 inches or 81% of the month's total of 27.8 inches.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:45 and sunrise is at 7:16. Sunset is at 16:54 and twilight ends at 17:24. Chicago's sunset is two minutes earlier and twilight ends a minute earlier. There's a total of 9 hours, 38 minutes of daylight today and 10 hours, 39 minutes between twilights. Tomorrow twilight begins at 6:45 and sunrise is at 7:15. The moon is waning crescent. Illumination was 22% at midnight, will be 18% at noon and 14% at midnight tonight. Moonrise was at 3:59 and moonset is at 12:41. Moonrise is at 4:54 tomorrow. Moonlight time is 8 hours, 42 minutes.

My brother will be celebrating a birthday in three days. -Bernie-