February 13: ORD

Today is February 13th. It's the 44th day of the year. 321 days remain. It's week 7 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 34 and the normal low is 18. I've calculated the 30-year averages at 33 and 18.

On the warm side, in 1984 the high was 54 with the record warmest low of 40. In 1990 the high was 54 with a low of 28. Fifteen years later, in 2005, the high was 41 with a low of 35, a six degree spread. Other warm lows were 31 in both 1998 and 2001. The record high of 63 was set back in 1938. 23 of the last 30 highs were: 20s (9) and 30s (14). On the warmer side, six highs were: 40s (4) and 50s (2). On the colder side, one high was in the 10s (a.k.a. teens).

In looking back through the years to the first February at O'Hare in 1959, the following instances were notable: In 1975 the high was 18 with a low of 4, a cold day. In 1972 the high was 35 with a low of 29, a six degree spread. In 1970 the high was 19 with a low of 7, another cold day. In 1959 the high was 37 with a low of 33, a four degree spread.

More recently, there were small spreads of two degrees in 2000 (31/29), seven degrees in three years: 1979 (24/17), 1992 (34/27) and 2001 (38/31).

On the cold side, in 1988 the high was 19 with a low of -5. Two years earlier, in 1986, the high was 21 with a low of -6. Last year the high was 21 with a low of 7. In 1982 the high was 25 with a low of 3. Another cold low was 5 in 1981. The record low of -18 and record coldest high of -4 were set on the same day back in 1905. 20 of the last 30 lows have been: 10s (a.k.a. teens) (12) and 20s (8). Even colder, six lows have been: negative single digits (2) and single digits (4). On the warmer side, three lows were 30s and one was a 40 (the warmest low we've seen at 40 in 1984).

Today is a major day in Chicago's snow history. In 2007, 8.8 inches fell. This was the second day of a three day, 11.6 inch storm.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight began at 6:23 and sunrise was at 6:52. Sunset was at 17:24 and twilight ended at 17:52. There's a total of 10 hours, 32 minutes of daylight today and 11 hours, 29 minutes between twilights. Tomorrow twilight begins at 6:22 and sunrise is at 6:51. The moon is waning gibbous. Illumination was 84% at midnight, will be 80% at noon and 75% at midnight tonight. Moonset was at 8:31. Moonrise is at 22:33. Moonset is at 8:56 tomorrow. Moonlight time is 9 hours, 58 minutes which is 45 minutes shorter than yesterday.

Valentine's Day is tomorrow. The Daytona 500 is in two days. President's Day is in three days. -Bernie-