June 3: ORD

Today is June 3rd. It's the 155th day of the year. 211 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. Before this, the official site of record was on the south side of Chicago at Midway International Airport (MDW), beginning on Wednesday, July 1, 1942. From Friday, January 1, 1926 through Tuesday, June 30, 1942, the official site was at the University of Chicago. Before that, the official site was at various locations in Chicago going back to Monday, October 16, 1871. Observations taken from October 15, 1870 to October 8, 1871 were lost in the Great Chicago Fire.
 
According to the National Climatic Data Center (NCDC), the normal high is 76 and the normal low is 54. I've calculated the 33-year averages at 70 and 52.

On the warm side, in 1981 the high was 81 with a low of 62. Last year, in 2011, the high was 87 with a low of 55, a 32 degree spread. The record high of 95 was set way back in 1895, at a time when the official readings were taken adjacent to Lake Michigan. The record warmest low of 69 occurred in 1944 at Midway. 26 of the past 33 highs (79%) were in the: 60s (14) and 70s (12). There were consecutive highs in the 60s & 70s as follows: seven from 1985 through 1991, seven from 1994 through 2000 and nine from 2002 through 2010. 23 of the 26 highs (88%) of highs in the 60s & 70s over the past 33 years occurred in these three streaks! Five highs (15%) were in the warm 80s. Two highs (6%) were in the cool 50s. O'Hare's warmest June 3rd was in 1972 as the high was 92 (O'Hare's warmest high of the date) and low of 64 (O'Hare's warmest low of the date).

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 79 with a cold low of 42, a 37 degree spread. In 1972 the high was a hot 92 with a low of 64, a hot day. In 1971 the high was 85 with a low of 53, a 32 degree spread. In 1970 the high was a cool 62 degrees. In 1969 the high was a cool 57 with a low of 45, a cool day. In 1967 the high was 80 with a low of 43, a 37 degree spread. In 1963 the high was a hot 88 degrees.

More recently, there were additional large spreads of 35 degrees in 1986 (75/40), 32 degrees in 1984 (81/49), 32 degrees in 1994 (73/41) and 30 degrees in 1992 (80/50). The one additional small spread was five degrees in 1999 (65/60).

On the cool side, in 1993 (O'Hare's coolest June 3rd) the high was 54 (O'Hare's coolest high of the date) with a low of 47, a seven degree spread. In 1982 the high was 60 with a low of 43. Three years ago, in 2009, the high was 61 with a low of 43. In 2001 the high was 55 with a low of 49, a six degree spread. The other cold lows were 40 in 1986 (O'Hare's coldest low of June 3rd) and 41 in 1994. The other cool highs were 61 in 1998, 61 in 2003, 63 in 1985 and 64 in 2000. The record low of 37 and record coolest high of 48 were set on the same cold day in 1945 at Midway. Another cool high of 51 occurred way back in 1910. 28 of the last 33 lows (85%) were in the: 40s (13) and 50s (15). Five lows were in the warm 60s. O'Hare's second coolest June 3rd was in 1969 as the high was a cool 57 with a low of 45.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:44 and sunrise is at 5:18. Sunset is at 20:25 and twilight ends at 20:59. There's a total of 15 hours, 7 minutes of daylight today and 16 hours, 15 minutes between twilights. We  gained two minutes of daylight from yesterday. Tomorrow twilight begins at 4:44 and sunrise is at 5:18. The moon is waxing gibbous, heading towards the full Strawberry (a.k.a. Rose or Hot) moon tomorrow morning at 6:12. Illumination was 98% at midnight, will be 99% at noon and 100% at midnight tonight. Moonset was at 4:27 this morning. Moonrise is at 19:50 tonight. Moonset is at 5:25 tomorrow morning. Moonlight time is 8 hours, 37 minutes which is 23 minutes shorter than yesterday. 

Spring began on March 12th and runs for 84 days through today, June 3rd. Warm Spring began on April 13th and runs for 52 days through today, June 3rd. High temperatures in this period are usually in the 50s, 60s and 70s. Highs in the 80s and 90s occur infrequently. Flag Day is in 11 days.