July 14: ORD

Today is July 14th. It's the 195th day of the year. 170 days remain. It's week 28 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 84 and the normal low is 63. I've calculated the 32-year averages at 85 and 64.

On the hot side, in 1995 the high was the co-record high of 100 with the record warmest low of 83. In 1988 the high was the co-record high of 100 with a low of 69, a 31 degree spread. In 1980 the high was 97 with a low of 71. Another 90s high of note was 95 in 1983. The warmest of the 70s lows was 73 in 1997 and 72 in 2006. 16 of the past 32 highs (50%) were in the 80s. 11 of the 80s highs (69% of them) occurred from 1999 through 2009. Eight highs (25%) were in the warm: 90s (6) and 100s (2). Eight highs (25%) were in the cool: 60s (1) and 70s (7). Our most recent 70s high was 77 in 1996. Through 2010, this is the average eighth hottest day of the year.

In looking back through the years to the first July at O'Hare in 1959, the following instances were notable: In 1977 the high was 98 with a low of 77, a hot day. In 1976 the high was a hot 98 with a low of 72, a hot day. In 1974 the high was 95 with a low of 74, a hot day. In 1974 yesterday (on the 13th) the high was also 95. In 1967 the high was 70 with a low of 51, a cool day. That low of 51 was colder than the record low. In 1962 the high was a cool 69 with a low of 62, a seven degree spread. In 1960 the high was a cool 71 degrees.

More recently, there was a large spread of 32 degrees in 2002 (88/56).

On the cool side, in 1990 the high was 65 with a low of 60, a small spread of five degrees. A couple of years later, in 1992, the high was 70 with a low of 60. The coolest lows were 55 two years ago (in 2009) and in 2003. The record low of 52 was set back in 1926. The record coolest high of 64 occurred back in 1930. 20 of the last 32 lows (63%) were in the 60s. Five lows (15%) were in the cool 50s. Seven lows (22%) were in the warm: 70s (6) and 80s (1).

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:56 and sunrise is at 5:29. Sunset is at 20:29 and twilight ends at 21:02. There's a total of 15 hours of daylight today and 16 hours, 6 minutes between twilights. We lost no minutes of daylight from yesterday. Tomorrow twilight begins at 4:57 and sunrise is at 5:30. The moon is waxing gibbous and will be full as the full Buck or Thunder moon tomorrow at 1:40. Illumination was 99% at midnight, will be 100% at noon and 100% at midnight tonight. Moonset is at 4:49 this morning. Moonrise is at 20:03 tonight. Moonset is at 5:55 tomorrow morning. Moonlight time is 8 hours, 46 minutes which is 21 minutes longer than yesterday.

Summer began June 4 and runs for 110 days through September 21. High temperatures in this period are usually in the 70s and 80s. Highs in the 60s, 90s and 100s occur infrequently. Parent's Day is in ten days.