February 21: ORD

Today is February 21st. It's the 52nd day of the year. 313 days remain. It's week 8 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 37 and the normal low is 21. I've calculated the 32-year averages at 39 and 24.

On the warm side, in 1991 the high was 58 with a low of 34. In 1980 the high was 46 with a low of 36. Other warm highs were 50 in 2003 and 49 in 1983. Other warm lows were 37 in 1985 and 33 in 2005. The record high of 67 and record warmest low of 47 were set on the same day back in 1930. 27 of the last 32 highs (84%) were in the: 30s (14) and 40s (13). On the warmer side, two highs were in the 50s. On the cold side, three highs were in the 20s.

In looking back through the years to the first February at O'Hare in 1959, the following instances were notable: In 1978 the high was 25 with a low of 7, a cold day. In 1976 the low was a warm 33 degrees. In 1975 the high was a warm 49 degrees. In 1974 the high was 51 with a low of 36, a warm day. In 1968 the high was 22 with a low of -1, a cold day. In 1967 the high was 25 with a low of 3, a cold day. In 1966 the high was 26 with a cold low of -1, another cold day. In 1965 the low was a cold 7 degrees. In 1963 the high was 4 with a low of -8, another very cold day. 1963 was the year of the record coldest high (3 at Midway). In 1961 the high was a warm 54 with a low of 21, a 33 degree spread.

More recently, there were small spreads of three degrees in 2005 (36/33), three degrees last year (36/33), five degrees in 2002 (34/29), six degrees in 1985 (43/37) and seven degrees in 1996 (35/28).

On the cold side, in 2001 the high was 21 with a low of 9. Three years ago (in 2008) the high was 23 with a low of 8. Two decades earlier, in 1988, the high was 32 with a low of 1, a 31 degree spread. The record low of -11 was set way back in 1873 and the record coldest high of 3 was set in 1963. 18 of the last 32 lows (56%) were in the 20s. Six lows (19%) were in the cold: single digits (3) and 10s (a.k.a. teens) (3). Eight lows (25%) were in the warmer 30s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:13 and sunrise is at 6:41. Sunset is at 17:33 and twilight ends at 18:02. There's a total of 10 hours, 52 minutes of daylight today and 11 hours, 49 minutes between twilights. We gained three minutes of daylight from yesterday. Tomorrow twilight begins at 6:11 and sunrise is at 6:40. The moon is waning gibbous. Illumination was 88% at midnight, will be 84% at noon and 79% at midnight tonight. Moonset is at 8:04 this morning. Moonrise is at 22:15 tonight. Moonset is at 8:39 tomorrow morning. Moonlight time is 9 hours, 49 minutes which is 46 minutes shorter than yesterday.

President's Day is today and Washington's Birthday is tomorrow. -Bernie-