March 25: ORD

Today is March 25th. It's the 84th day of the year. 281 days remain. It's week 12 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 50 and the normal low is 31. I've calculated the 31-year averages at 50 and 33.

On the warm side, three years ago the high was the record high of 79 with a low of 48, a 31 degree spread. The former record high was 75, first in 1939 and then in 1967. In 1986 the high was 72 with a low of 51. In 2004 the high was 62 with the record warmest low of 57, a five degree spread. The record warmest low of 57 also occurred in 1945. In 1988 the high was 62 with a low of 44. In 2000 the high was 61 with a low of 44. Other warm highs were 65 in 1991 and 63 in 1989. 17 of the last 31 highs were: 40s (9) and 50s (8). On the warmer side, seven highs were: 60s (5) and 70s (2). On the colder side, seven highs were: 30s (5) and 20s (2).

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 32 with a low of 25, a seven degree spread and cold day. In 1977 the high was a warm 62 with a low of 30, a 32 degree spread. In 1976 the high was a warm 67 with a low of 34, a 33 degree spread. In 1975 the high was 32 with a low of 23, a cold day. In 1974 the high was 44 with a cold low of 10, a 34 degree spread. That low of 10 was colder than the record low. In 1973 the high was 47 with a low of 40, a seven degree spread. In 1971 the high was a cold 38. In 1969 the high was a cold 35. In 1968 the high was a warm 67 with a low of 38, a warm day. In 1967 the high was a warm 75 with a low of 41, a 34 degree spread and warm day. In 1966 the high was 37 with a low of 16, a cold day. In 1965 the high was 26 with a low of 17, another cold day. In 1964 the high was a cold 35 with a low of 22, yet another cold day. In 1963 the high was 65 with a low of 55, a warm day. In 1960 the high was 25 with a low of 9, a cold day. That low of 9 was another reading that was colder than the record. In 1959 the high was 43 with a low of 36, a seven degree spread.

More recently, we had small spreads of six degrees in 2005 (39/33) and seven degrees in 1980 (35/28). There were large spreads of 32 degrees in 1981 (57/25), 32 degrees in 1991 (65/33), 33 degrees in 1995 (58/25) and 40 degrees in 1996 (56/16).

On the cold side, in 1979 the high was 25 with a low of 16. In 2001 the high was 25 with a low of 19, a six degree spread. In 1983 the high was 32 with a low of 20. In 2002 the high was 31 with a low of 24, a seven degree spread. Another cold low was 16 in 1996. Other cold highs were 35 in 1980 and 38 in 1999. The record low of 12 was set in 1940 and more recently in 1974. The record coldest high of 19 was set way back in 1894. 21 of the last 31 lows were: 20s (10) and 30s (11). Three lows were in the colder 10s (a.k.a. teens). Seven lows were in the warmer: 40s (5) and 50s (2).

Today is a major day in Chicago's snow history. At O'Hare in 1965, this was the sixth of seven days in which a total of 10.2 inches fell. Today 0.2 inches fell. In 1970 at O'Hare, this was the second of five days in which 11.8 inches fell. Today 5.8 inches fell. At Midway in 1970, 5.4 inches fell. This was the first of two days in which a total of 14.3 inches fell. In 1930 at the University of Chicago, a total of 21.6 inches fell on the 24th and 25th. 14.4 inches fell in an unspecified 24 hour time frame during these two days. Tom Skilling of WGN-TV said in his blog that the total was 19.2 inches. So there appears to be a slight discrepancy between the totals.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight began at 6:20 and sunrise was at 6:48. Sunset is at 19:11 and twilight ends at 19:39. Chicago's sunset is at 19:09 and end of twilight is at 19:36. There's a total of 12 hours, 23 minutes of daylight today and 13 hours, 19 minutes between twilights. Tomorrow twilight begins at 6:18 and sunrise is at 6:46. The moon reached first quarter two days ago at 6:00. Illumination was 70% at midnight, will be 75% at noon and 80% at midnight tonight. Moonset was at 4:02 this morning. Moonrise is at 14:06. Moonset is at 4:36 tomorrow morning. Moonlight time is 13 hours, 56 minutes which is 34 minutes shorter than yesterday.

Palm Sunday is in three days. April Fool's Day is in a week. -Bernie-