June 21: ORD

Today is June 21st. It's the 172nd day of the year. 193 days remain. It's week 25 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 81 and the normal low is 59. I've calculated the 31-year averages at 83 and 61.

On the hot side, in 1988 the high was the record high of 101 with a low of 71, a 30 degree spread. The other hot high was 93 in 1991. The other warm low was 71 in 2002. The record warmest low of 74 occurred back in 1923. 19 of the last 31 highs were 80s. Four highs were in the hot: 90s (3) and 100s (1). Eight highs were in the cooler: 60s (3) and 70s (5).

In looking back through the years to the first June at O'Hare in 1959, the following instances were notable: In 1972 the high was a cool 68. In 1969 the high was 65 with a low of 46, a cool day. In 1968 the high was a hot 93. In 1967 the high was a cool 68. In 1963 the high was 64 with a low of 41, a cool day. In 1962 the high was 83 with a low of 53, a 30 degree spread. In 1961 the high was 75 with a cold low of 44, a 31 degree spread.

More recently, the spreads were large: 33 degrees in 2003 (80/47), 30 degrees in 1986 (92/62) and 30 degrees in 1991 (93/63).

On the cool side, in 1992 the high was 61 with the record low of 38. Another cool low was 47 in 2003. Other cool highs were 67 in 2004 and 69 in 2001. The record coolest high of 56 occurred way back in 1881. 18 of the last 31 lows were 60s. Ten lows were in the cooler: 30s (1), 40s (1) and 50s (8). Three lows were in the warmer 70s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight began at 4:42 and sunrise was at 5:17. Sunset is at 20:33 and twilight ends at 21:08. There's a total of 15 hours, 16 minutes of daylight today and 16 hours, 26 minutes between twilights. Tomorrow twilight begins at 4:43 and sunrise is at 5:17. The moon is waxing gibbous. Illumination was 72% at midnight, will be 77% at noon and 82% at midnight tonight. Moonset was at 1:30 this morning. Moonrise is at 16:06 and moonset is at 2:03 tomorrow morning. Moonlight time is 9 hours, 24 minutes which is 42 minutes shorter than yesterday.

Independence Day is in 13 days. - Bernie -