February 24: ORD

Today is February 24th. It's the 55th day of the year. 310 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 38 and the normal low is 22. I've calculated the 32-year averages at 38 and 22.

On the warm side, in 2002 the high was 61 with a low of 38 (our most recent 30s low). A couple of years earlier, in 2000, the high was 57 with a low of 41. Four years before that, in 1996, the high was 58 with a low of 34. Two years later, in 1998, the high was 54 with a low of 36. Three years later, in 2001, the high was 56 (our most recent 50s high) with a low of 30. Two decades earlier, in 1981, the high was 53 with a low of 32. The record high of 64 was set in 1930 and the record warmest low of 46 occurred in 1936. 15 of the last 32 highs (47%) were in the 30s. On the warmer side, ten highs (31%) were in the: 40s (4), 50s (5) and 60s (1). On the cold side, seven highs (22%) were in the: 10s (a.k.a. teens) (1) and 20s (6).

In looking back through the years to the first February at O'Hare in 1959, the following instances were notable: In 1977 the high was a warm 51 with a low of 33, a warm day. In 1976 the high was 63 with a low of 38, another warm day. In 1974 the high was a cold 22 with a low of 13, a cold day. In 1967 the high was 9 with a low of -6, another cold day. In 1965 the high was a cold 24 with a low of 19, a five degree spread. In 1964 the high was 29 with a cold low of 4, a cold day. In 1963 the high was 26 with a low of -1, a cold day. In 1962 the high was 29 with a low of 24, a five degree spread. In 1960 the high was 29 with a low of 23, a six degree spread.

More recently, we had small spreads of: six degrees in 2004 (37/31), six degrees in 2007 (32/26), seven degrees in 1979 (30/23), seven degrees in 1985 (39/32), seven degrees in 1992 (40/33) and a large spread of 32 degrees in 2006 (47/15).

On the cold side, in 1993 the high was 15 with a low of -5. In 1989 the high was 22 with a low of 4. In 2003 the high was 23 with a low of 6. In 1994 the high was 22 with a low of 8. Another cold low was 7 in 1990 and another cold high was 26 in 1988. The record low of -11 was set way back in 1873 and the record coldest high of 8 occurred back in 1889. 20 of the last 32 lows (63%) were in the: 20s (11) and 30s (9). 11 lows (34%) were in the cold: 10s (a.k.a. teens) (6), single digits (4) and negative single digits (1). One low (3%) was in the warmer 40s.

Today is a major day in Chicago's snow history. In 1994, 0.3 inches fell. This was the third of four days in which 16.1 inches fell. In 1965, 6.7 inches fell. This was the second of three days in which 10.0 inches fell.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:09 and sunrise is at 6:37. Sunset is at 17:37 and twilight ends at 18:05. There's a total of 11 hours of daylight today and 11 hours, 56 minutes between twilights. We gained two minutes of daylight from yesterday. Tomorrow twilight begins at 6:07 and sunrise is at 6:35. The moon reaches last quarter today at 17:26. Illumination was 58% at midnight, will be 53% at noon and 47% at midnight tonight. Moonrise is at 40 minutes past midnight this morning. Moonset is at 10:02 this morning. Moonrise is at 1:44 tomorrow morning. Moonlight time is 9 hours, 22 minutes which is 5 minutes longer than yesterday.

Mardi Gras is in 12 days. Ash Wednesday is in 13 days. The cool part of Spring (Cool Spring) begins in 16 days on March 12. Cool Spring runs for 32 days, through April 12. High temperatures in this period are usually in the 30s, 40s and 50s. Warmer 60s and 70s occur infrequently. -Bernie-