January 1: ORD

Today is January 1st. It's the 1st day of the year. 365 days remain. It's week 1 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. Observations have been official at O'Hare 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 32 and the normal low is 17. I've calculated the 33-year averages at 32 and 18.

On the warm side, in 2000 the high was 48 with a low of 35. Three years before, in 1997, the high was 39 with a low of 33, a six degree spread. In 2007 the high was 43 with a low of 29. In 1994 the high was 41 with a low of 30. In 2006 the high was 45 with a low of 26. The other warm high was 49 in 2004. The other warm lows were 32 in 1996, 31 in 1992 and 30 in 1987. The record high of 65 was set way back in 1876, at a time when the official readings were taken adjacent to Lake Michigan. The record warmest low of 43 was set in 1950 at Midway. 31 of the past 33 highs (94%) were in the: 20s (9), 30s (14) and 40s (8). On the cold side, two highs were in the: single digits (1) and 10s (a.k.a. teens) (1). Our first 10s (a.k.a. teens) high of 16 occurred two years ago in 2010. Four straight years (2004-2007) had 40s highs. These were, in order: 49, 41, 45 and 43. O'Hare has never had a high of 50 or higher for the date.

In looking back through the years to the first January at O'Hare in 1959, the following instances were notable: in 1978 the high was 32 with a cold low of -1, a 33 degree spread. In 1977 the high was 13 with a low of 1, a cold day. In 1976 the high was 38 with a warm low of 33, a five degree spread and warm day. In 1974 the high was 8 with a low of -3, a cold day. In 1972 the high was 41 with a warm low of 33, a warm day. In 1971 the low was a warm 31 degrees. In 1970 the high was 29 with a low of 22, a seven degree spread. In 1969 the high was 5 with a low of -7, a cold day. 1969 was the year of the record coldest high of 5 and record low of -10. In 1968 the high was 16 with a low of -11, a cold day. In 1965 the high was 38 with a warm low of 34, a four degree spread and warm day. In 1964 the high was 25 with a cold low of -13, a 35 degree spread and cold day.

More recently, we had small spreads of three degrees in 1987 (33/30), five degrees in 1990 (30/25), five degrees in 1992 (36/31), six degrees in 1996 (38/32), six degrees in 2003 (33/27), seven degrees in 1981 (33/26) and seven degrees in 1982 (21/14).

On the cold side, in 1988 the high was 8 with a low of -1. O'Hare also had a high of 8 in 1974 and it's coldest high was 5 in 1969. Two years ago, in 2010, the high was 16 with a low of 5. The other cold lows were 4 in 1979, 4 in 2008 and 5 in 2001. The record low of -10 and record coldest high of 5 were set on the same cold day in 1969 at Midway. 20 of the last 33 lows (61%) were in the: 10s (a.k.a. teens) (11) and 20s (9). On the cold side, seven lows (21%) were in the: negative single digits (1) and single digits (6). O'Hare's coldest lows were -13 in 1964 and -11 in 1968. On the warm side, six lows (18%) were in the 30s. Our most recent 30s low was 35 in 2000. O'Hare has never had a low of 40 or higher for the date.

There was an instance of back-to-back years in which temperatures were just about as opposite as they can be. In 1999 the high was 22 with a low of 6, overall 10 degrees BELOW normal. Then in 2000 the high was 48 with a low of 35, overall 17.5 degrees ABOVE normal.

Today is a major snow day in O'Hare's history. In 1999, 2.0 inches fell. This was the first day of a three day, 21.6 inch storm. This storm comprised 73% of the month's total of 29.6 inches.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:50 and sunrise is at 7:22 (the latest sunrise of the year). Sunset is at 16:32 and twilight ends at 17:03. There's a total of 9 hours, 10 minutes of daylight today and 10 hours, 13 minutes between twilights. We gained a minute of daylight from yesterday. Tomorrow twilight begins at 6:51 (the latest start to twilight) and sunrise is at 7:22 (the latest sunrise of the year). The moon reaches first quarter this morning at 15 minutes past midnight. Illumination was 50% at midnight, will be 55% at noon and 59% at midnight tonight. Moonset was at 0:12 this morning. Moonrise is at 11:24 this morning. Moonset is at 1:11 tomorrow morning. Moonlight time is 11 hours, 12 minutes which is an hour and 50 minutes shorter than yesterday.

Winter began December 1st and runs for 102 days through March 11th. High temperatures in this period are usually in the 20s and 30s. Highs in the 40s and 50s occur infrequently. New Year's Day is today. Martin Luther King, Jr. Day is in 15 days.