June 8: ORD

Today is June 8th. It's the 159th day of the year. 206 days remain. It's week 23 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 78 and the normal low is 55. I've calculated the 32-year averages at 79 and 56.

On the hot side, in 2004 the high was 91 with a low of 74. Five years earlier, in 1999, the high was 92 with a low of 68. In 1984 the high was 86 with a low of 71. A year later, in 1985, the high was 95 with a low of 62, a 33 degree spread. In 2000 the high was 89 with a low of 66. Five years later, in 2005, the high was 89 with a low of 66. The other 90s highs were 93 in 1979 and 91 in 1987. The record high of 97 and record warmest low of 77 were set on the same hot day back in 1933. 14 of the past 32 highs (44%) were in the 80s. Five highs (15%) were in the hot 90s. 13 highs (41%) were in the cool: 50s (1), 60s (6) and 70s (6). Our most recent 70s high was 74 in 2001.

Yesterday, June 7, 2011 was the warmest June 7th O'Hare has ever had. The high was 96 at 15:52 with a low of 75 at 4:46. It was also the warmest day at O'Hare since August 1 & 2, 2006 when highs were 99 and 97 degrees. Rockford had a high of 96 at 16:25 with a low of 72 at 6:15.

In looking back through the years to the first June at O'Hare in 1959, the following instances were notable: In 1978 the high was a cool 64 degrees. In 1969 the high was a cool 59 with a low of 45, a cool day. In 1968 the high was a hot 91 with a low of 66, a hot day. In 1967 the low was a warm 70 degrees. In 1964 the high was a hot 92 with a low of 56, a 36 degree spread and hot day. In 1962 the high was 85 with a low of 53, a 32 degree spread. In 1959 the high was 91 with a low of 68, a hot day.

More recently, there were large spreads of 38 degrees in 1983 (81/43), 36 degrees in 1979 (93/57) and 35 degrees in 1987 (91/56).

On the cool side, in 1996 the high was 61 with a low of 45. A year earlier, in 1995, the high was the only 50s high of 58 with a low of 49. Other cool highs were 63 in 1994 and 66 in 1980. Other cool lows were 43 in both 1983 and 1998. The record low of 42 was set way back in 1885. The record coolest high of 51 occurred back in 1913. 30 of the last 32 lows (94%) were in the: 40s (9), 50s (11) and 60s (10). Our most recent 40s low was 48 in 2001. Two lows were in the warm 70s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:43 and sunrise is at 5:17. Sunset is at 20:28 and twilight ends at 21:02. There's a total of 15 hours, 11 minutes of daylight today and 16 hours, 19 minutes between twilights. We gained a minute of daylight from yesterday. Tomorrow twilight begins at 4:43 and sunrise is at 5:17. The moon reaches first quarter tonight at 21:11. Illumination was 41% at midnight, will be 46% at noon and 52% at midnight tonight. Moonset is at 0:27 this morning. Moonrise is at 12:29 this afternoon. Moonset is at 0:56 tomorrow morning. Moonlight time is 11 hours, 58 minutes which is 44 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. Flag Day is in six days. Father's Day is in 11 days.