May 25: ORD

Today is May 25th. It's the 145th day of the year. 220 days remain. It's week 21 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 73 and the normal low is 51. I've calculated the 31-year averages at 68 and 49.

On the warm side, in 2006 the high was 75 with the only 60s low of 64. In 1989 the high was 76 with a low of 58. What's interesting about the highs today is that all of the 80s highs of the last 31 years happened between 1980 and 1985. It was 82 in 1980, 80 in 1981 and 84 in 1985. The record high of 94 was set back in 1911 and the record warmest low of 72 was set back in 1914. 28 of the 31 highs (90%) have been: 50s (7), 60s (11) and 70s (10). Three highs were in the warmer 80s.

In looking back through the years to the first May at O'Hare in 1959, the following instances were notable: In 1978, the high was 82 with a low of 52, a 30 degree spread. In 1977 the high was a hot 90 with a low of 62, a hot day. In 1975 the low was a warm 66. In 1972 the high was a warm 85. In 1971 the high was a cool 60. In 1967 the high was 84 with a low of 49, a 35 degree spread. In 1965 the high was 82 with a warm low of 67, a warm day. In 1964 the high was 80 with a low of 48, a 32 degree spread. In 1961 the low was a cold 39 degrees.

More recently, there was a small spread of seven degrees in 1990 (60/53). There were large spreads of 34 degrees in 1985 (84/50), 34 degrees two years ago (78/44), 31 degrees in 1981 (80/49) and 30 degrees in 1980 (82/52).

On the cool side, in 1992 the high was 51 with the record low of 32. In 1988 the high was 59 with a low of 37. In 1983 the high was 59 with a low of 38. In 2002 the high was 57 with a low of 41. In 1997 the high was 54 with a low of 45. In 1996 the high was 56 with a low of 45. Other cool highs were 59 in 2001 and 60 in 1990. The record coolest high of 44 was set way back in 1893. 27 of the 31 lows (87%) were: 40s (13) and 50s (14). Three low were in the colder 30s and one low was in the warmer 60s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight began at 4:51 and sunrise was at 5:24. Sunset is at 20:17 and twilight ends at 20:51. There's a total of 14 hours, 53 minutes of daylight today and 16 hours between twilights. Tomorrow twilight begins at 4:50 and sunrise is at 5:23. The moon is waxing gibbous, heading towards the full Flower moon in two days at 18:07. Illumination was 91% at midnight, will be 94% at noon and 96% at midnight tonight. Moonset was at 3:28 this morning. Moonrise is at 18:17 this evening. Moonset is 4:03 tomorrow morning. Moonlight time is 9 hours, 11 minutes which is 42 minutes shorter than yesterday.

1979 was the most tragic day in O'Hare's history. 273 people lost their lives when an American Airlines DC 10-10, flight 191, crashed shortly after taking off. One of the three engines, the one attached to the left wing, separated and fell onto the runway as the aircraft was gaining speed for takeoff. The aircraft nosedived adjacent to a mobile home park. It was a miracle that loss of life on the ground was not extensive, as just one person was killed. Today marks the 31st anniversary of the crash.

Memorial Day is in six days. - Bernie -