January 3: ORD

Today is January 3rd. It's the 3rd day of the year. 363 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 31 and the normal low is 17. I've calculated the 33-year averages at 33 and 19.

On the warm side, in 1998 the high was the near-record high of 58 with a low of 35. The record high of 60 was first set way back in 1874 (adjacent to Lake Michigan) and most recently in 1950 at Midway. In 2004 the high was 52 with a low of 30. These were O'Hare's only 50s highs for the date. In 1993 the high was 46 with a low of 35. In 2006 the high was 42 with a low of 39 (O'Hare's warmest low of the date), a three degree spread. A year later, in 2007, the high was 48 with a low of 33. A decade before that, in 1997, the high was 45 with a low of 35. In 1990 the high was 44 with a low of 33. Two years later, in 1992, the high was 41 with a low of 36, a five degree spread. The other warm lows were 32 in 2000, 32 in 2005 and 30 in 1982. The record warmest low of 46 was set way back in 1874, at a time when the official readings were taken adjacent to Lake Michigan. 27 of the past 33 highs (82%) were in the: 20s (8), 30s (13) and 40s (7). On the warm side, two highs were in the 50s. On the cold side, four highs were in the: single digits (1) and 10s (a.k.a. teens) (3).

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 18 with a low of 2, a cold day. In 1976 the low was a cold 5 degrees. In 1975 the high was 36 with a warm low of 31, a five degree spread. In 1974 the high was 21 with a cold low of 3, a cold day. In 1970 the high was a cold 18 with a low of 7, a cold day. In 1969 the high was 20 with a cold low of -5, a cold day. In 1968 the high was 20 with a cold low of 3 degrees, a cold day. In 1967 the low was a cold 3 degrees. In 1964 the high was 38 with a warm low of 31, a seven degree spread. In 1963 the high was 32 with a low of 26, a six degree spread. In 1962 the high was 42 with a warm low of 30, a warm day. In 1961 the high was 24 with a cold low of 1 degree, a cold day. In 1959 the high was 21 with a cold low of -1, a cold day.

More recently, we had small spreads of three degrees in 1980 (31/28), four degrees in 1994 (32/28), four degrees in 2005 (36/32), five degrees in 1982 (35/30) and six degrees in 2000 (38/32).

On the cold side, in 1979 the high was 4 with a low of -15 (this was O'Hare's coldest January 3rd). In 1991 the high was 16 with a low of -2. In 1985 the high was 20 with a low of -6. Two years ago, in 2010, the high was 18 with a low of -1. In 1981 the high was 22 with a low of -5. In 1995 the high was 18 with a low of 3. In 2008 the high was 23 with a low of 0. The other cold low was 5 in 1999. The record low of -18 and record coldest high of 0 were set on the same cold day way back in 1879, at a time when the official readings were taken adjacent to Lake Michigan. 11 of the last 33 lows (33%) were in the 30s. 13 lows (40%) were in the cold: 10s (a.k.a. teens) (7) and 20s (6). Nine lows (27%) were in the very cold: negative 10s (a.k.a. negative teens) (1), negative single digits (4) and single digits (4).

There were two instances of back-to-back years in which temperatures were just about as opposite as they can be. In the first instance, in 1990 the high was 44 with a low of 33, overall 14.5 degrees ABOVE normal. Then in 1991 the high was 16 with a low of -2, overall 17 degrees BELOW normal. In the second instance, in 2007 the high was 48 with a low of 33, overall 16.5 degrees ABOVE normal. Then in 2008, the high was 23 with a low of 0, overall 12.5 degrees BELOW normal.

Today is a major snow day in O'Hare's history. In 1999, an inch fell. This was the third 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 6:51 (the latest start to twilight) and sunrise is at 7:22 (the latest sunrise of the year). Sunset is at 16:33 and twilight ends at 17:05. There's a total of 9 hours, 11 minutes of daylight today and 10 hours, 14 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 is waxing gibbous, having reached first quarter two mornings ago at 15 minutes past midnight. Illumination was 68% at midnight, will be 73% at noon and 77% at midnight tonight. Moonset was at 2:11 this morning. Moonrise is at 12:22 this afternoon. Moonset is at 3:09 tomorrow morning. Moonlight time is 10 hours, 11 minutes which is 29 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. Martin Luther King, Jr. Day is in 13 days.