May 20: ORD

Today is May 20th. It's the 141st day of the year. 225 days remain.

Unless noted, the following data is based upon observations collected by the National Weather Service, Chicago, at O'Hare International Airport (ORD) between 1979 and 2007. Observations have been official at O'Hare since Jan. 17, 1980.

Before this, Midway International Airport (MDW) was the official station of record from Wed. July 1, 1942 to Thu. Jan. 17, 1980. Before July 1, 1942, records were official at various locations in the city going all the way back to Mon. Oct. 16, 1871. Records before this (back to Sat. Oct. 15, 1870) were lost during the Great Chicago Fire which began on the evening of Sun. Oct. 8, 1871.

According to the National Climatic Data Center (NCDC), the normal high for today is 71 and the normal low is 50.
The 29-year averages are 72 and 47.

On the warm side, 2004 was the only mean of 12 degrees or more above normal: high of 84 with the only 60s low of 63. There have been a total of just three 80s highs. The other two were 84 in 1992 and 82 in 1987. The upper 70s highs were 79 in 1996, a high of 78 three times (1979, 1994 and 1999) and 77 in 2001. None of the 50s lows were in the upper 50s. 24 of the 29 highs have been in the 60s (9) and 70s (15). The year 1977 holds both records on the warm side: the record high of 95 and record warmest low of 70.

On the cool side, in 2002 the high was 48 (only 40s high) with the record low of 33 (former record low was 35 in 1981). In 1986, the high was 56 (only 50s high) with a low of 41. Other 30s lows were 38 in 2006 and 39 in 1997. The record coolest high of 40 occurred way back in 1895. 24 of the 29 lows have been in the 40s (15) and 50s (9).

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:54 and sunrise is at 5:27. Sunset is at 20:13 and twilight ends at 20:46. There's a total of 14 hours, 46 minutes of sunlight and 15 hours, 52 minutes between twilights. The moon is waning gibbous with 100% visible at midnight and 99% visible at noon. Moonset is at 5:17 and moonrise is at 21:23. Moonlight time is 7 hours, 54 minutes today. The moon was full at 21:11 yesterday (the full Flower moon).

Memorial Day is in six days.

- Bernie -