November 14: ORD

Today is November 14th. It's the 318th day of the year. 47 days remain. It's week 46 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 was on the south side of Chicago at Midway International Airport (MDW), beginning on Wednesday, July 1, 1942. 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 49 and the normal low is 33. I've calculated the 33-year averages at 50 and 33.

On the warm side, in 2001 the high was 62 with a low of 51. In 1989 the high was 62 with a low of 46. Two years ago, in 2009, the high was 63 with a low of 43. The other warm highs were 66 in 1990 and 62 in 1994. The record high of 78 was set in 1971 at Midway. The record warmest low of 59 occurred in 1958 at Midway. The past 33 highs have been fairly evenly distributed: 30s (7 for 21%), 40s (10 for 31%), 50s (8 for 24%) and 60s (8 for 24%). Our most recent 30s high was 36 in 2000. There were three consecutive 30s highs (1995-1997) and three consecutive 40s highs (1978-1980). All of the 70s highs (three of them) occurred prior to 1978. The only 20s highs also occurred prior to 1978 (two of them).

In looking back through the years to the first November at O'Hare in 1958, the following instances were notable: in 1976 the high was 39 with a cold low of 15, a cold day. In 1974 the high was a cold 30 with a low of 23, a cold day with a small seven degree spread. In 1973 the high was a warm 65 degrees. In 1971 the high was 77 with a low of 48, a warm day and year of the record high of 78 at Midway. In 1969 the high as 28 with a low of 20, a cold day. In 1965 the low was a cold 20 degrees. In 1964 the high was a warm 70 with a low of 37, a 33 degree spread and warm day. In 1962 the high was a warm 61 with a low of 27, a 34 degree spread. In 1960 the high was 69 with a low of 48, a warm day. In 1959 the high was 26 with a low of 13, a cold day. That high of 26 is near the record coldest high of 24. The low of 13 is actually colder than the record low of 14. In 1958 the high was 71 with a low of 57, a warm day and year of the record warmest low of 59 at Midway.

More recently, there were large spreads of 35 degrees in 1981 (61/26), 31 degrees in 1990 (66/35) and 31 degrees in 1999 (60/29). There were small spreads of three degrees in 1993 (46/43) and five degrees in 1997 (38/33).

On the cold side, in 1986 the high was 34 with a low of 15. That low of 15 was only a degree warmer than the record low. A decade later, in 1996, the high was 33 with a low of 17. That low of 17 is our most recent 10s low. In 1982 the high was 30 with a low of 20. In 1995 the high was 37 with a low of 18. As you can see, the back to back years of 1995 and 1996 had lows in the 10s. In 1992 the high was 35 with a low of 20. The other cold high was 36 in 2000 (our most recent 30s high). The record low of 14 and record coldest high of 24 were set on the same cold day back in 1916. The record low of 14 first occurred 16 years earlier in 1900. 23 of the last 33 lows (70%) were in the: 20s (10) and 30s (13). Three lows were in the cold 10s (a.k.a. teens) (9%). There were also two 10s lows prior to 1978. Seven lows (21%) were in the warm: 40s (6) and 50s (1). There was one other 50s low prior to 1978 (57 in 1958). Our most recent 20s lows were back to back to back: 23 in 2003, 26 in 2004 and 28 in 2005. This was part of six consecutive 20s & 30s lows from 2002 though 2007. There was also a string of eight consecutive 20s & 30s lows from 1978 through 1985.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:12 and sunrise is at 6:42. Sunset is at 16:33 and twilight ends at 17:03. There's a total of 9 hours, 51 minutes of daylight today and 10 hours, 51 minutes between twilights. We lost two minutes of daylight from yesterday. Tomorrow twilight begins at 6:13 and sunrise is at 6:44. The moon is waning gibbous. Illumination was 90% at midnight, will be 86% at noon and 83% at midnight tonight. Moonset is at 10:02 this morning. Moonrise is at 19:39 tonight. Moonset is at 10:44 tomorrow morning. Moonlight time is 14 hours, 23 minutes which is 12 minutes less than yesterday.

Cool Fall began November 2 and runs for 29 days through November 30. High temperatures in this period are usually in the 30s, 40s and 50s. Highs in the 10s and 20s occur infrequently. Thanksgiving is in ten days.