April 9: ORD

Today is April 9th. It's the 99th day of the year. 266 days remain. It's week 15 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.

According to the National Climatic Data Center (NCDC), the normal high is 55 and the normal low is 36. I've calculated the 32-year averages at 52 and 33.

On the warm side, in 1994 the high was 67 with a low of 48. In 1988 the high was 68 with a low of 38, a 30 degree spread. Other warm highs were 68 in 2005 and 72 in 1987. The record high of 80 was set way back in 1887. The record warmest low of 58 occurred back in 1922. 25 of the last 32 highs (78%) were in the: 40s (10) and 50s (15). On the warmer side, five highs were in the: 60s (4) and 70s (1). On the cold side, two highs were in the 30s.

In looking back through the years to the first April at O'Hare in 1959, the following instances were notable: In 1977 the high was 63 with a low of 29, a 34 degree spread. In 1976 the high was 60 with a low of 28, a 32 degree spread. In 1975 the high was a cold 39 with a low of 33, a six degree spread. In 1973 the high was a cold 41 degrees. In 1972 the high was 43 with a low of 24, a cold day. In 1969 the high was 71 with a low of 52, a warm day. In 1967 the high was 75 with a low of 49, a warm day. In 1964 the high was 56 with a low of 25, a 31 degree spread. In 1961 the high was a cold 37 with a low of 33, a four degree spread. In 1960 the high was a cold 37 with a low of 25, a cold day. In 1959 the high was a cold 43 degrees.

More recently, we had small spreads of four degrees in 1998 (45/41) and seven degrees in 1980 (40/33). The large spreads were 45 degrees in 1987 (72/27) and 33 degrees in 2005 (68/35). Taking a closer look at 1987, the mean was 49.5 which is only 4.5 degrees above normal, but the high and low were significantly above and below normal.

On the cold side, in 1989 the high was 37 with the record low of 20. In 1997 the high was 38 with a low of 22. In 1985 the high was 42 with a low of 21. In 1979 the high was 40 with a low of 26. In 1982 the high was 40 with a low of 27. Other cold highs were 40 in 1980, 42 in 1995, 43 in 2003 and 43 in 2007. The record coldest high of 33 occurred way back in 1874. 17 of the last 32 lows (53%) were in the 30s. Ten lows (31%) were in the cold 20s. Five lows (16%) were in the warmer 40s. Our most recent 40s low was 44 in 2001.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 5:54 and sunrise is at 6:23. Sunset is at 19:28 and twilight ends at 19:57. There's a total of 13 hours, 5 minutes of daylight today and 14 hours, 3 minutes between twilights. We gained two minutes of daylight from yesterday. Tomorrow twilight begins at 5:52 and sunrise is at 6:21. The moon is waxing crescent, heading towards first quarter in two days at 7:05. Illumination was 27% at midnight, will be 32% at noon and 37% at midnight tonight. Moonset was at 0:42 this morning. Moonrise is at 9:58 later this morning. Moonset is at 1:30 tomorrow morning. Moonlight time is 14 hours, 44 minutes which is 12 minutes shorter than yesterday.

The warm part of Spring (Warm Spring) begins in four days on April 13. Warm Spring runs for 52 days, through June 3. High temperatures in this period are usually in the 50s, 60s and 70s. Warmer 80s and 90s occur infrequently. Palm Sunday is in eight days. -Bernie-