July 2: ORD

Today is July 2nd. It's the 183nd day of the year. 182 days remain. It's week 27 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 82 and 60.

On the hot side, in 2002 the high was 93 with a low of 75. There was only one other 90s high: 96 in 1991. Three highs just missed the 90 degree mark: 89 in: 1992, 1997 and 2003. The record high of 99 was set in 1970. The record warmest low of 79 occurred back in 1911. 19 of the last 31 highs were 80s. Two highs were in the warmer 90s. Ten highs were in the cooler 70s, including last year's 73.

In looking back through the years to the first July at O'Hare in 1959, the following instances were notable: In 1978 the high was 73 with a low of 66, a seven degree spread. In 1973 the low was a warm 74. In 1970 the high was 95 with a low of 78, a hot day and year of the record high of 99 at Midway. In 1968 the high was a cool 67 with a low of 51, a cool day. In 1966 the high was 93 with a low of 59, a 34 degree spread.

More recently, there were large spreads of: 34 degrees in 1984 (83/49) and 32 degrees in 1979 (82/50).

On the cool side, no days had means of at least 11.5 degrees below normal. The cool lows were the record low of 49 which occurred in 1984 and was tied in 2001. The coolest high was 70 in 1994. There have been no highs of 71 or 72 but three at 73, the most recent occurrence was last year. The record coolest high of 62 occurred in 1940. 28 of the last 31 lows (90%) were: 50s (13) and 60s (15). 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 4:47 and sunrise was at 5:21. Sunset is at 20:33 and twilight ends at 21:08. There's a total of 15 hours, 12 minutes of daylight today and 16 hours, 21 minutes between twilights. Tomorrow twilight begins at 4:47 and sunrise is at 5:21. The moon is waning gibbous. Illumination was 72% at midnight, will be 68% at noon and 63% at midnight tonight. Moonset is at 11:25 this morning. Moonrise is at 23:34 tonight and moonset is at 12:25 tomorrow afternoon. Moonlight time is 11 hours, 51 minutes which is 39 minutes longer than yesterday.

Independence Day is in two days. - Bernie -