June 17: ORD

Today is June 17th. It's the 168th day of the year. 197 days remain. It's week 24 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 80 and the normal low is 58. I've calculated the 32-year averages at 81 and 59.

On the hot side, in 1984 the high was 92 with the record-tying warmest low of 77. The original record warmest low of 77 occurred in 1957. In 2006 the high was 92 with a low of 72. In 1994 the high was 93 with a low of 70. In 2007 the high was 91 with a low of 70. Another hot high was 94 in 1987. Other 90s were 91 in 1993 and 90 in 1995. The record high of 96 was tied in 1957, having first being set way back in 1887. Along with the co-record low of 77, this makes 1957 the warmest June 17th. 28 of the past 32 highs (88%) were in the: 70s (10), 80s (11) and 90s (7). Four highs were in the cool 60s.

In looking back through the years to the first June at O'Hare in 1959, the following instances were notable: In 1977 the high was 93 with a low of 72, a hot day. In 1976 the high was 85 with a low of 54, a 31 degree spread. In 1974 the high was a cool 65 with a low of 50, a cool day. In 1972 the high was 66 with a low of 46, a cool day. In 1970 the low was a warm 72 degrees. In 1965 the high was 69 with a cool low of 45, a cool day. In 1963 the high was 82 with a low of 48, a 34 degree spread. In 1961 the high was 79 with a low of 49, a 30 degree spread. In 1960 the high was a cool 64 with a low of 51, a cool day.

More recently, four spreads were large: 35 degrees in 1987 (94/59), 33 degrees in 2001 (87/54), 31 degrees in 1982 (76/45) and 30 degrees in 1989 (80/50).

On the cool side, in 1999 the high was 66 with a low of 48. In 1980 the high was 74 with the record low of 42. Another cool low was 45 in 1982. Other cool highs were 64 in 2000 and 67 in 1986. The record coolest high of 57 occurred way back in 1879. 25 of the last 32 lows (78%) were in the: 50s (15) and 60s (10). Three lows were in the cool 40s and four were in the warm 70s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:42 and sunrise is at 5:16. Sunset is at 20:32 and twilight ends at 21:07. There's a total of 15 hours, 16 minutes of daylight today and 16 hours, 25 minutes between twilights. We gained no minutes of daylight from yesterday. Tomorrow twilight begins at 4:42 and sunrise is at 5:17. The moon is waning gibbous and was full two days ago as the full Strawberry moon at 15:14. Other names for this moon are Rose and Hot. Illumination was 98% at midnight, will be 96% at noon and 93% at midnight tonight. Moonset is at 7:05 this morning. Moonrise is at 22:07 tonight. Moonset is at 8:12 tomorrow morning. Moonlight time is 8 hours, 58 minutes which is 26 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. Father's Day is in two days. Independence Day is in 17 days.