July 1: ORD

Today is July 1st. It's the 182nd day of the year. 183 days remain. It's week 26 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 82 and the normal low is 61. I've calculated the 31-year averages at 81 and 59.

On the hot side, in 2002 the high was 93 with a low of 75. The other 90s high of note was 97 in 1991. The record high of 103 was set in 1956. The record warmest low of 78 occurred back in 1931. 23 of the last 31 highs were: 70s (11) and 80s (12). Six highs were in the warmer 90s. Two highs were in the cooler 60s, including last year's 65 which was cooler than 1986's 66.

In looking back through the years to the first July at O'Hare in 1959, the following instances were notable: In 1974 the high was 89 with a low of 57, a 32 degree spread. In 1970 the high was 94 with a low of 76, a hot day. In 1966 the high was 92 with a low of 61, a 31 degree spread. In 1965 the high was 81 with a cool low of 40, a 41 degree spread and cool day. In 1963 the high was 95.

More recently, there were large spreads of: 34 degrees in 1989 (89/55), 33 degrees in 1979 (84/51), 33 degrees in 1992 (91/58), 30 degrees in 1982 (76/46) and 30 degrees in 1991 (97/67).

On the cool side, no days had means of at least 11.5 degrees below normal. The cool lows were the record low of 46 in 1982 and a low of 49 in 1984. These were the only 40s lows. The coolest highs were 65 last year, 66 in 1986 and 70 in 1981. The record coolest high of 61 occurred back in 1924. 28 of the last 31 lows were: 50s (15) and 60s (13). Two lows were in the cooler 40s and one low was in the warmer 70s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight began at 4:46 and sunrise was at 5:21. Sunset is at 20:34 and twilight ends at 21:08. There's a total of 15 hours, 13 minutes of daylight today and 16 hours, 22 minutes between twilights. Tomorrow twilight begins at 4:47 and sunrise is at 5:21. The moon is waning gibbous. Illumination was 80% at midnight, will be 76% at noon and 72% at midnight tonight. Moonset was at 10:25 this morning. Moonrise is at 23:13 and moonset is at 11:25 tomorrow morning. Moonlight time is 11 hours, 12 minutes which is 39 minutes longer than yesterday.

Independence Day is in three days. - Bernie -