May 8: ORD

Today is May 8th. It's the 128th day of the year. 237 days remain. It's week 19 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 67 and the normal low is 45. I've calculated the 31-year averages at 70 and 48.

On the warm side, in 1979 the high was a near-record 90 degrees with an above-record low of 68. The record warmest low is 67, set in 1963 at Midway. The 68 degree low at O'Hare is not the official reading of record for Chicago since O'Hare was not the official station of record in 1979; Midway was. In 2000 the high was 85 with a near-record low of 66. In 1993 the high was 85 with a low of 59. In 1990 the high was 81 with a low of 60. In 1988 the high was 85 with a low of 52, a 33 degree spread. To complete the listing of days of 11.5 or more degrees above normal mean, three years ago the high was 82 with a low of 54. Other 80s highs were 84 in 2004 and 85 in 2005. The other mid 70s highs were 76 in 2001 and 77 last year. There were three other lows in the 50s: 53 last year, 52 in 1998 and 51 in 1997. The record high of 91 was set in 1963. 1963 was a scorchingly hot day as it's mean was 22 and a half degrees above normal. 26 of the last 31 highs were: 60s (9), 70s (9) and 70s (8). On the warmer side, one high was in the 90s. On the cooler side, one high was in the 40s and five highs were in the 50s.

In looking back through the years to the first May at O'Hare in 1959, the following instances were notable: In 1977 the high was 70 with a low of 34, a 36 degree spread. In 1976 the high was 64 with a low of 34, a 30 degree spread. In 1974 the high was 45 with a low of 42, a three degree spread and cool day. In 1972 the high was 44 with a low of 39, a five degree spread and cool day. In 1971 the high was 74 with a low of 41, a 33 degree spread. In 1970 the high was 86 with a low of 63, a hot day. In 1968 the high was 78 with a low of 57, a warm day. In 1966 the high was a cold 45 with a low of 35, a cold day. In 1965 the high was 83 with a low of 61, a warm day. In 1964 the high was 79 with a low of 61, a warm day. In 1963 the high was 90 with a low of 67, a hot day. 1963 was also the year of the record high and record warmest low. In 1960 the high was a cold 41 with a low of 35, a six degree spread and cold day. 1960 was also the year of the record coldest high.

More recently, we had large spreads of 31 degrees in 1981 (63/32), 32 degrees in 1992 (72/40), 35 degrees in 2004 (84/49) and 42 degrees in 2005 (85/43).

On the cool side, in 1983 the high was 48 with the record low of 29. The year later, 1984, the high was 51 with a low of 38. Another cold low was 32 in 1981. The only other 30s low was 39 in 1994. Another cool high was 54 in 1980. The record coolest high of 42 was set in 1960. 18 of the last 31 lows were 40s. Four lows were in the colder: 20s (1) and 30s (3). Nine lows were in the warmer: 50s (6) and 60s (3).

Today is not a major day in Chicago's snow history. Stay tuned, for in three days we had what was our last snow event for the Spring.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight began at 5:09 and sunrise was at 5:40. Sunset is at 20:00 and twilight ends at 20:32. There's a total of 14 hours, 20 minutes of daylight today and 15 hours, 23 minutes between twilights. Tomorrow twilight begins at 5:07 and sunrise is at 5:39. The moon is waning crescent. Illumination was 31% at midnight, will be 27% at noon and 22% at midnight tonight. Moonrise was at 2:46 early this morning. Moonset is at 14:48. Moonrise is at 3:07 early tomorrow morning. Moonlight time is 12 hours, 2 minutes which is 38 minutes longer than yesterday.

Mother's Day is tomorrow. - Bernie -