November 2: ORD

Today is November 2nd. It's the 306th day of the year. 59 days remain. It's week 44 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 55 and the normal low is 38. I've calculated the 33-year averages at 54 and 37.

On the warm side, in 1990 the high was 73 (our most recent 70s high) with a low of 58. Three years earlier, in 1987, the high was 71 with a low of 58. The other warm highs were 70 in 1978 and 67 three years ago, in 2008 (our most recent 60s high). The other warm lows were 53 in 1983 and 50 in 1981. The record high of 78 was set in 1974 at Midway. The record warmest low of 62 occurred in 1944 at Midway. 26 of the past 33 highs (79%) were in the: 40s (8), 50s (10) and 60s (8). Our most recent 40s high was 49 in 2004. Three highs were in the warm 70s and four were in the cold 30s.

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 73 with a low of 56, a warm day. In 1975 the high was 73 with a low of 56, a warm day. In 1974 the high was 74 with a low of 49, a warm day and year of the record high of 78 at Midway. In 1971 the high was a warm 68 degrees. In 1970 the high was 44 with a low of 40, a four degree spread. In 1969 the high was 47 with a low of 44, a three degree spread. In 1967 the high was 48 with a low of 41, a seven degree spread. In 1966 the high was a cold 39 with a low of 27, a cold day. In 1965 the high was a warm 68 with a low of 38, a 30 degree spread. In 1964 the high was 66 with a warm low of 51, a warm day. In 1963 the high was 47 with a cold low of 22 degrees, a cool day. In 1962 the low was a cold 24 degrees. In 1961 the high was 77 with a low of 56, a warm day. In 1960 the high was a cold 42 with a low of 38, a four degree spread.

More recently, there were large spreads of 31 degrees in 1978 (70/39) and 31 degrees in 1995 (60/29). There were small spreads of four degrees in 2004 (49/45) and seven degrees in 2003 (55/48).

On the cold side, in 1991 the high was 32 with a low of 18, O'Hare's only low in the 10s (aka teens). In 1984 the high was 36 with a low of 21. Five years ago, in 2006, the high was 34 with a low of 24. A decade earlier, in 1996, the high was 37 with a low of 22. In 1989 the high was 41 with a low of 26. The other cold low was 25 in 1980. The record low of 14 and record coldest high of 29 were set on the same cold day in 1951 at Midway. 28 of the last 33 lows (85%) were in the: 20s (8), 30s (13) and 40s (7). One low was in the cold 10s (18 in 1991). This was O'Hare's only low in the 10s (aka teens). Four lows were in the warm 50s, most recently 58 in 1990.

There's an instance of back-to-back years in which temperatures were just about as opposite as they can be. In 1990 the high was 73 with a low of 58, overall 18.5 degrees ABOVE normal. Then in 1991 the high was 32 with a low of 18, overall 22 degrees BELOW normal.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:58 and sunrise is at 7:27. Sunset is at 17:46 and twilight ends at 18:15. There's a total of 10 hours, 19 minutes of daylight today and 11 hours, 17 minutes between twilights. We lost two minutes of daylight from yesterday. Tomorrow twilight begins at 6:59 and sunrise is at 7:29. The moon reaches first quarter today at 11:38. Illumination was 46% at midnight, will be 51% at noon and 56% at midnight tonight. Moonrise is at 13:46 this afternoon. Moonset is at 0:33 tomorrow morning. Moonrise is at 14:14 tomorrow afternoon. Moonlight time is 10 hours, 14 minutes which is two minutes shorter 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. Election Day is in six days. Veterans Day is in nine days.