October 21: ORD

Today is October 21st. It's the 294th day of the year. 71 days remain. It's week 42 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 60 and the normal low is 40. I've calculated the 31-year averages at 60 and 43.

On the warm side, in 1979 the high was 84 with the record warmest low of 70. Three years ago (2007) the high was 80 with a low of 60. That low of 60 was the first low in the 60s of the past 31 years. In 1986 the high was 77 with a low of 52. Last year (2009) the high was 69 with a low of 55. Another warm high was 72 in 1994. The record high of 87 was set in 1953. Over the last 31 years, 24 highs (77%) have been: 50s (14) and 60s (10). Four highs were in the warmer: 70s (2) and 80s (2). Three highs were in the cooler 40s.

In looking back through the years to the first October at O'Hare in 1959, the following instances were notable: in 1978 the high was 80 with a low of 53, a warm day. In 1977 the high was a warm 74 degrees. In 1976 the high was a cool 46 with a low of 30, a cool day. In 1975 the high was a warm 73 degrees. In 1974 the low was a cold 27 degrees. In 1973 the high was 67 with a low of 37, a 30 degree spread. In 1971 the high was 73 with a low of 66, a seven degree spread and warm day. In 1968 the high was 69 with a low of 38, a 31 degree spread. In 1963 the high was 69 with a warm low of 59, a warm day. In 1961 the high was 49 with a low of 44, a five degree spread. In 1960 the high was 49 with a cold low of 27, a cool day.

More recently, there were large spreads of 32 degrees in 1991 (67/35), 32 degrees in 1999 (68/36) and 31 degrees in 1994 (72/41). There were small spreads of five degrees in 1983 (56/51) and seven degrees in 1995 (43/36).

On the cool side, in 1987 the high was 42 with a low of 32. Another cold low was 27 in 1982, our only 20s low. Another cool high was 43 in 1995. The only other 40s high was 49 in 1997. The record low of 26 was set in 1952 and the record coolest high of 39 occurred back in 1913. 24 of the last 31 lows (77%) were: 30s (13) and 40s (11). One low was in the cooler 20s. Six lows were in the warmer: 50s (4), 60s (1) and 70s (1).

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:45 and sunrise is at 7:13. Sunset is at 18:02 and twilight ends at 18:31. There's a total of 10 hours, 49 minutes of daylight today and 11 hours, 46 minutes between twilights. We are losing two or three minutes of daylight a day. Tomorrow twilight begins at 6:46 and sunrise is at 7:14. The moon is waxing gibbous, heading towards the full Hunter's moon tomorrow night at 20:36. It's also known as the Travel or Dying Grass moon. Illumination was 97% at midnight, will be 98% at noon and 99% at midnight tonight. Moonset is at 5:53 this morning. Moonrise is at 17:03 this afternoon. Moonset is at 6:55 tomorrow morning. Moonlight time is 12 hours, 50 minutes which is 37 minutes longer than yesterday.

United Nation's Day is in three days. Halloween is in ten days. Election Day is in 12 days. Veteran's Day is in 21 days. -Bernie-