November 8: ORD

Today is November 8th. It's the 313th day of the year. 53 days remain. It's week 45 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. From Friday, January 1, 1926 through Tuesday, June 30, 1942, the official site was at the University of Chicago. 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 52 and the normal low is 36. I've calculated the 34-year averages at 53 and 35.

On the warm side, three years ago, in 2009, the high was 70 (O'Hare's second warmest high of the date) with a low of 45. In 1983 the high was 64 with a low of 48. In 2002 the high was 63 with a low of 48. The other warm highs were 71 degrees in 1999 (O'Hare's warmest high of the date), 68 degrees in 1964, 67 degrees two years ago in 2010, 66 degrees in 1981, 64 degrees in 1984 and 64 degrees in 2006. The 70s highs (71 in 1999 and 70 in 2009) are the only 70s in O'Hare's history for the date. The other warm low was 48 degrees in 1994. The record high of 73 degrees was set in 1931 at the University of Chicago. The record warmest low of 57 degrees occurred in 1977 at Midway. 29 of the past 34 highs (85%) were in the: 40s (10), 50s (9) and 60s (10). Two highs were in the warm 70s. Three highs were in the cold 30s. Our most recent 30s high is 33 degrees in 2003. O'Hare's warmest November 8th was in 1977 as the high was 63 with a low of 56 (O'Hare's warmest low of the date). O'Hare's second warmest November 8th was in 1975 as the high was 65 with a low of 51 (O'Hare's second warmest low of the date).

In looking back through the years to the first November at O'Hare in 1958, the following instances were notable: in 1977 the high was 63 with a warm low of 56, a seven degree spread, warm day and year of the record warmest low of 57. In 1976 the high was 37 with a low of 16, a cold day. In 1975 the high was 65 with a low of 51, a warm day. In 1973 the low was a cold 23 degrees. In 1972 the high was 43 with a low of 38, a five degree spread. In 1971 the high was 42 with a cold low of 20, a cold day. In 1968 the high was a cold 39 degrees. In 1967 the low was a cold 23 degrees. In 1964 the high was a warm 68 with a low of 36, a 32 degree spread. In 1962 the high was 43 with a low of 37, a six degree spread. In 1961 the high was a cold 38 degrees. In 1960 the high was 43 with a low of 37, a six degree spread.

More recently, there was a large spread of 33 degrees in 1999 (71/38). There were small spreads of four degrees last year, in 2011 (51/47), five degrees in 2008 (40/35) and seven degrees in 1998 (40/33). 

On the cool side, in 1991 (O'Hare's coolest November 8th) the high was 32 with the record low of 11. Four years later, in 1995 (O'Hare's second coolest November 8th), the high was 32 with a low of 18 (O'Hare's third coldest low of the date). Those highs of 32 degrees are O'Hare's coolest highs of the date. In 2003 the high was 33 (O'Hare's second coolest high of the date and our most recent 30s high) with a low of 21 (our most recent 20s low). In 1990 the high was 40 with a low of 22. The other cold lows were 23 degrees in both 1967 and 1973. The other cool highs are 38 degrees in 1961, 39 degrees in 1968 and 40 degrees in 1998 and a decade later in 2008. 17 of the last 34 lows (50%) were in the 30s. Seven lows (21%) were in the cold: 10s (2) and 20s (5). Ten lows (29%) were in the warm 40s. The other cool days were in: 1976 (high of 37, low of 16 (O'Hare's second coldest low of the date)) and 1971 (high of 42, low of 20). 

There was an instance of back-to-back years in which temperatures were just about as opposite as they can be. In 2002 the high was 63 with a low of 48, overall 11.5 degrees ABOVE normal. Then in 2003 the high was 33 with a low of 21, overall 17 degrees BELOW normal.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:06 and sunrise is at 6:36. Sunset is at 16:38 and twilight ends at 17:08. There's a total of 10 hours, 2 minutes of daylight today and 11 hours, 2 minutes between twilights. We lost three minutes of daylight from yesterday. Tomorrow twilight begins at 6:07 and sunrise is at 6:37. The moon reached last quarter two nights ago at 18:36. Illumination was 38% at midnight, will be 33% at noon and 28% at midnight tonight. Moonrise was at 0:25 this morning. Moonset is at 13:24 this afternoon. Moonrise is at 1:31 tomorrow morning. Moonset is at 13:54 tomorrow afternoon. Moonlight time is 12 hours, 59 minutes which is four minutes longer than yesterday.  

Cool Fall began on November 2nd and runs for 29 days through November 30th. High temperatures in this period are usually in the 30s, 40s and 50s. Highs in the 20s, 60s and 70s occur infrequently. Veteran's Day is in three days. Thanksgiving is in 14 days.