May 16: ORD

Today is May 16th. It's the 136th day of the year. 229 days remain. It's week 20 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 70 and the normal low is 47. I've calculated the 31-year averages at 71 and 48.

On the warm side, in 2001 the high was 89 with a low of 64. A decade earlier, in 1991, the high was 86 with a low of 63. The next year, 1992, the high was 88 with a low of 58, a 30 degree spread. In 1998 the high was 82 with a low of 62. In 1986 the high was 79 with a low of 62. Other mid 80s highs were all 83 degrees, in 1982, 1987 and 1999. Other warm lows were 60 in 1990 and 59 in 1995. The record high of 94 and record warmest low of 69 were set on the same day in 1962. 15 of the highs over the last 31 years have been 60s. 15 highs were in the warmer: 70s (8) and 80s (7). One high was in the cooler 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 86 with a low of 61, a hot day. In 1969 the high was 85 with a low of 60, a warm day. In 1962 the high was 92 with a low of 69, a hot day. 1962 was also the year of the record high and record warmest low.

More recently, we had a small spread of 6 degrees in 1996 (57/51). The large spreads were: 40 degrees in 1987 (83/43), 35 degrees in 1997 (68/33), 33 degrees in 2004 (70/37), 33 degrees last year (73/40) and 32 degrees in 1981 (75/43).

On the cool side, no means were at least 11 and a half degrees below normal, but there were some cooler temperatures. In 1996 the high was just 57, O'Hare's only sub-60 degree high for the date. Colder lows were 35 in 1983 and the record low of 33, occurring in 1997. The former record low of 34 occurred way back in 1888. The record coolest high of 44 was set way back in 1891. 16 of the last 31 lows were 40s. Four lows were in the colder 30s. 11 lows were in the warmer: 50s (6) and 60s (5).

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight began at 4:59 and sunrise was at 5:31. Sunset is at 20:09 and twilight ends at 20:41. There's a total of 14 hours, 38 minutes of daylight today and 15 hours, 42 minutes between twilights. Tomorrow twilight begins at 4:58 and sunrise is at 5:30. The moon is waxing crescent. Illumination was 6% at midnight, will be 9% at noon and 12% at midnight tonight. Moonrise was at 7:25 this morning. Moonset is at 23:15. Moonrise is at 8:33 tomorrow morning. Moonlight time is 15 hours, 50 minutes which is 6 minutes shorter than yesterday.

A sister of mine, Maria, celebrates a birthday today. National Maritime Day is in six days. - Bernie -