March 4: ORD

Today is March 4th. It's the 63rd day of the year. 302 days remain. It's week 9 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 41 and the normal low is 25. I've calculated the 32-year averages at 42 and 25.

On the warm side, in 1983 the high was the record high of 73 with the record warmest low of 50. In 1992 the high was 64 with a low of 35. In 2000 the high was 62 with a low of 29, a 33 degree spread. Another warm low was 38 in 2004. 26 of the last 32 highs (81%) were in the: 30s (12) and 40s (14). On the warmer side, four highs were in the: 50s (1), 60s (2) and 70s (1). On the cold side, two highs were in the: 20s (1) and 10s (a.k.a. teens) (1). High temperatures were in the 30s or 40s the last eight years.

In looking back through the years to the first March at O'Hare in 1959, the following instances were notable: In 1978 the high was 18 with a low of 3, a cold day. In 1976 the high was a warm 53 degrees. In 1975 the low was a cold 13 degrees. In 1974 the low was a warm 39 degrees. In 1973 the low was a warm 37 degrees. In 1970 the high was a warm 55 degrees. In 1968 the high was a warm 60 with a low of 27, a 33 degree spread. In 1967 the high was 32 with a low of 26, a six degree spread. In 1966 the high was a warm 53 degrees. In 1963 the high was 38 with a low of 33, a five degree spread. In 1962 the high was a cold 29 degrees. In 1961 the high was 54 with a low of 37, a warm day. In 1960 the high was 19 with a low of 7, a cold day.

More recently, we had small spreads of three degrees in 1993 (36/33), five degrees in 1981 (37/32) and six degrees in 2004 (44/38).

On the cold side, in 2002 the high was 19 with a low of -7. In 2007 the high was 31 with a low of 14. In 1982 the high was 27 with a low of 18. Another cold low was 10 in 1996. The record low of -12 was set way back in 1873. The record coldest high of 17 occurred way back in 1890. 19 of the last 32 lows (59%) were in the 20s. Five lows (16%) were in the cold: negative single digits (1) and 10s (a.k.a. teens) (4). Eight lows (25%) were in the warmer: 30s (7) and 50s (1). There have been no lows as cold as the negative single digits or the much warmer 40s.

Today is a major day in Chicago's snow history. In 2002, 0.3 inches fell. This was the fourth of four days in which a total of 10.2 inches fell. This comprised 91% of the month's total of 11.2 inches. In 1982, 8.5 inches fell. This was the third of three days in which 12.1 inches fell.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 5:56 and sunrise is at 6:24. Sunset is at 17:47 and twilight ends at 18:15. There's a total of 11 hours, 23 minutes of daylight today and 12 hours, 19 minutes between twilights. We gained four minutes of daylight from yesterday. Tomorrow twilight begins at 5:54 and sunrise is at 6:22. The moon is new this afternoon at 14:46. Illumination was 1% at midnight, will be 0% at noon and 0% at midnight tonight. Moonrise is at 5:57 this morning. Moonset is at 17:58 this afternoon. Moonrise is at 6:19 tomorrow morning. Moonlight time is 12 hours, 1 minute which is 37 minutes longer than yesterday.

Mardi Gras is in four days. Ash Wednesday is in five days. The cool part of Spring (Cool Spring) begins in eight 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-