April 29: ORD

Today is April 29th. It's the 119th day of the year. 246 days remain. It's week 17 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 63 and the normal low is 42. I've calculated the 31-year averages at 63 and 43.

On the warm side, in 2004 the high was 78 with a low of 59. Other warm highs were 83 in 1987, 82 two years ago and 75 in 2001. Another warm low was 54 in 1991. The record-tying high of 88 and record warmest low of 68 were set on the same day at Midway in 1970. The co-record high of 88 occurred way back in 1899. 26 of the last 31 highs were: 50s (8), 60s (11) and 70s (7). On the warmer side, two highs were in the 80s. On the cooler side, three highs were in the 40s.

In looking back through the years to the first April at O'Hare in 1959, the following instances were notable: in 1978 the high was 70 with a low of 40, a 30 degree spread. In 1977 the high was 64 with a cold low of 30, a 34 degree spread. In 1975 the high was a warm 76 with a low of 39, a 37 degree spread. In 1974 the high was 69 with a warm low of 60, a warm day. In 1971 the high was a cold 51. In 1970 the high was 86 with a low of 69, a hot day (day of the records). In 1969 the high was a cold 51. In 1966 the high was 67 with a low of 36, a 31 degree spread. In 1965 the high was 70 with a low of 35, a 35 degree spread. In 1961 the low was a cold 30.

More recently, we had large spreads of 38 degrees in 1987 (83/45), 37 degrees three years ago (82/45), 33 degrees in 1985 (69/36), 32 degrees in 1988 (65/33) and 31 degrees in 1986 (74/43).

On the cold side, two years ago the high was 44 with a record-tying low of 31. In 1996 the high was 45 with a low of 36. Another cold high was 48 in 1979. The co-record low of 31 occurred in 1958. O'Hare had a low of 30 degrees in 1977 but at the time O'Hare was not the official station of record for Chicago. The record coldest high of 39 was set way back in 1893. 20 of the last 31 lows were 40s. Eight low were in the colder 30s. Three lows were in the warmer 50s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight began at 5:21 and sunrise was at 5:52. Sunset is at 19:50 and twilight ends at 20:21. There's a total of 13 hours, 58 minutes of daylight today and 15 hours between twilights. Tomorrow twilight begins at 5:20 and sunrise is at 5:50. The moon is waning gibbous, having reached the full Pink moon yesterday at 7:18. Illumination was 99% at midnight, will be 98% at noon and 96% at midnight tonight. Moonset was at 6:08 this morning. Moonrise is at 21:44. Moonset is at 6:53 tomorrow morning. Moonlight time is 8 hours, 24 minutes which is 31 minutes shorter than yesterday.

National Teacher Day is in six days. Mother's Day is in ten days. - Bernie -