June 10: ORD

Today is June 10th. It's the 161st day of the year. 204 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 56. I've calculated the 32-year averages at 78 and 56.

On the hot side, in 2000 the high was 88 with a low of 72. Two years later, in 2002, the high was 88 with a low of 71. Three years prior, in 1999, the high was 90 with a low of 67. The record high of 98 was set back in 1911. The record warmest low of 74 occurred back in 1933. 26 of the past 32 highs (81%) were in the: 70s (13) and 80s (13). One high was in the hot 90s. Five highs were in the cool: 50s (1) and 60s (4).

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 82 with a low of 45, a 37 degree spread. In 1977 the high was 77 with a cold low of 44, a 33 degree spread. In 1974 the high was a cool 66 degrees. In 1973 the high was a hot 90 degrees. In 1972 the high was 57 with a low of 40, a cool day. In 1968 the high was 92 with a low of 70, a hot day. In 1966 the high was 65 with a low of 44, a cool day. In 1961 the high was 89 with a low of 58, a 31 degree spread. In 1959 the low was a warm 72 degrees.

More recently, the spreads were all large: 37 degrees in 1994 (80/43), 34 degrees in 1987 (78/44), 31 degrees in 1995 (83/52), 30 degrees in 1992 (79/49) and 30 degrees in 1997 (82/52).

On the cool side, in 1980 the high was 57 with the record low of 42. In 1988 the high was 68 with a low of 44. The other cool lows were 43 in 1994 (our most recent 40s low) and 44 in 1987. The other cool high was 63 in 2006. The record coolest high of 54 occurred way back in 1883. 19 of the last 32 lows (59%) were in the 50s. Five lows (16%) were in the cool 40s. Eight lows (25%) were in the warm: 60s (6) and 70s (2). An interesting observation is that all of the 40s lows (over the last 33 years) occurred between 1980 and 1994.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:42 and sunrise is at 5:17. Sunset is at 20:29 and twilight ends at 21:03. There's a total of 15 hours, 12 minutes of daylight today and 16 hours, 21 minutes between twilights. We gained one minute of daylight from yesterday. Tomorrow twilight begins at 4:42 and sunrise is at 5:17. The moon reached first quarter two nights ago at 21:11 and is waxing gibbous. Illumination was 63% at midnight, will be 69% at noon and 74% at midnight tonight. Moonset is at 1:24 this morning. Moonrise is at 14:54 this afternoon. Moonset is at 1:55 tomorrow morning. Moonlight time is 10 hours, 30 minutes which is 45 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 four days. Father's Day is in nine days.