July 9: ORD

Today is July 9th. It's the 190th day of the year. 175 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 83 and the normal low is 63. I've calculated the 32-year averages at 85 and 64.

On the hot side, in 1989 the high was 97 with a low of 71. A year earlier, in 1988, the high was also 97 but with a "cooler" low of 68. The other 90s highs of note were 95 in 1984, 94 in 2007 and 93 in 1987. The record high of 98 was set at Midway in 1974. The record warmest low of 79 occurred way back in 1897. 24 of the past 32 highs (75%) were in the: 80s (15) and 90s (9). Eight highs (25%) were in the cool: 60s (2) and 70s (6).

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 a hot 97 degrees (the low was 68). 1974 was the year of the record high of 98 at Midway. In 1963 the high was 72 with a cold low of 47 (colder than the record low), a cool day. In 1961 the high was 79 with a cold low of 49 (colder than the record low), a 30 degree spread.

More recently, there was a large spread of 32 degrees in 2005 (88/56).

On the cool side, in 1997 the high was 69 with a low of 53. A year earlier, in 1996, the high was also 69 but with a "warmer" low of 56. Those were the only highs not to make it to at least 70. Our coolest 70s highs were 74 degrees in both 1994 and 2003. The record low of 50 and record coolest high of 63 occurred on the same cool day way back in 1895. 18 of the last 32 lows (56%) were in the 60s. Seven lows (22%) were in the cool 50s. Seven lows (22%) were in the warm 70s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:52 and sunrise is at 5:26. Sunset is at 20:31 and twilight ends at 21:05. There's a total of 15 hours, 5 minutes of daylight today and 16 hours, 13 minutes between twilights. We lost two minutes of daylight from yesterday. Tomorrow twilight begins at 4:52 and sunrise is at 5:26. The moon is waxing gibbous, having passed first quarter yesterday morning at 1:29. Illumination was 61% at midnight, will be 67% at noon and 72% at midnight tonight. Moonset is at 0:31 this morning. Moonrise is at 15:10 this afternoon. Moonset is at 1:09 tomorrow morning. Moonlight time is 9 hours, 21 minutes which is 42 minutes shorter 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 15 days.