Thursday, May 31, 2012

May 31: ORD

Today is May 31st. It's the 152nd day of the year. 214 days remain. It's week 22 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 of record was on the south side of Chicago at Midway International Airport (MDW), beginning on Wednesday, July 1, 1942. From Friday, January 1, 1926 through Tuesday, June 30, 1942, the official site was at the University of Chicago. 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 75 and the normal low is 53. I've calculated the 33-year averages at 77 and 55.


On the hot side, in 1991 (O'Hare's warmest May 31st) the high was 89 with a low of 67. Last year, in 2011 (O'Hare's second warmest May 31st), the high was 85 with a low of 69 (O'Hare's warmest low of the date). In 1988 the high was 92 (O'Hare's only 90s high and thus warmest high of May 31st) with a low of 61, a 31 degree spread. In 2002 the high was 86 with a low of 67. In 1987 the high was 88 with a low of 64. Two years later, in 1989, the high was 84 with a low of 67. The other hot high was 87 in 1986. The other warm lows were 66 two years ago, in 2010 and 65 in both 2006 and 2007. The record high of 98 was set back in 1934 at the University of Chicago. The record warmest low of 72 occurred back in 1919, at a time when the official readings were taken adjacent to Lake Michigan.
26 of the past 33 highs (79%) were in the: 70s (15) and 80s (11). O'Hare recorded seven consecutive 70s & 80s highs from 2005 through last year, 2011. One high (3%) was in the hot 90s. Six highs (18%) were in the cool: 50s (2) and 60s (4).

In looking back through the years to the first May at O'Hare in 1959, the following instances were notable: In 1978 the high was a hot 88 with a low of 56, a 32 degree spread. In 1972 the high was a cool 63 degrees. In 1970 the low was a warm 70 degrees. In 1969 the high was 85 with a low of 53, a 32 degree spread. In 1966 the high was 66 with a cold low of 37, a cool day. In 1965 the high was 80 with a low of 44, a 36 degree spread. In 1963 the high was 80 with a low of 46, a 34 degree spread. In 1961 the high was 85 with a low of 53, a 32 degree spread.

More recently, there were additional large spreads of 36 degrees in 1990 (76/40), 33 degrees in 1992 (77/44), 33 degrees in 1996 (74/41), 31 degrees in 1981 (72/41) and 30 degrees in 1995 (84/54).

 
On the cool side, in 2003 (O'Hare's coolest May 31st) the high was 58 (O'Hare's coolest high of the date) with a low of 38. A decade earlier, in 1993, the high was 65 with a low of 39. The other cool lows were 40 in 1990, 41 in 1981 and 41 in 1996. The other cool highs were 59 in 1983 and 62 in 2001. Both records were set way back in the 19th century, at a time when the official readings were taken adjacent to Lake Michigan. The record low of 35 was set way back in 1873. The record coolest high of 43 occurred way back in 1889. 31 of the last 33 lows (94%) were in the: 40s (9), 50s (9) and 60s (13). Two lows (from 1979-2011) were in the cold 30s. O'Hare's third and only other 30s low was 37 in 1966 (O'Hare's coldest low of the date). The 50s highs (58 in 2003 and 59 in 1983) were O'Hare's only 50s highs for the date in its history. However, today's high (in 2012) is predicted to be in the 50s and may become O'Hare's coolest high ever 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 2002 the high was 86 with a low of 67,  overall 12.5 degrees ABOVE normal. Then in 2003 the high was 58 with a low of 38, overall 16 degrees BELOW normal.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:46 and sunrise is at 5:20. Sunset is at 20:23 and twilight ends at 20:57. There's a total of 15 hours, 3 minutes of daylight today and 16 hours, 11 minutes between twilights. We gained a minute of daylight from yesterday. Tomorrow twilight begins at 4:45 and sunrise is at 5:19. The moon is waxing gibbous. Illumination was 76% at midnight, will be 81% at noon and 85% at midnight tonight. Moonset was at 2:22 this morning. Moonrise is at 16:08 this afternoon. Moonset is at 2:57 tomorrow morning. Moonlight time is 10 hours, 14 minutes which is 42 minutes shorter than yesterday. 

Spring began on March 12th and runs for 84 days through June 3rd. Warm Spring began on April 13th and runs for 52 days through June 3rd. High temperatures in this period are usually in the 50s, 60s and 70s. Highs in the 80s and 90s occur infrequently. Flag Day is in 14 days.

May 30: ORD

Today is May 30th. It's the 151st day of the year. 215 days remain. It's week 22 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 of record was on the south side of Chicago at Midway International Airport (MDW), beginning on Wednesday, July 1, 1942. From Friday, January 1, 1926 through Tuesday, June 30, 1942, the official site was at the University of Chicago. 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 74 and the normal low is 53. I've calculated the 33-year averages at 78 and 55.


On the hot side, in 2006 (O'Hare's warmest May 30th) the high was 89 with a low of 67. In 1991 the high was 88 with a low of 66. Three years later, in 1994, the high was 90 with a low of 64. In 1987 the high was 85 with a low of 68. Two decades later, in 2007, the high was 87 with a low of 66. In 1980 the high was 86 with a low of 66. Three decades later (two years ago, in 2010), the high was 91 with a low of 61, a 30 degree spread. In 1988 the high was 91 with a low of 60, a 31 degree spread. Those highs of 91 in 1988 and 2010 are O'Hare's warmest highs of the date. The other warm highs were 88 last year, in 2011 and 87 in 1998. The record high of 93 was set in 1942 at the University of Chicago and tied in 1953 at Midway. The record warmest low of 72 occurred back in 1921, at a time when the official readings were taken adjacent to Lake Michigan.
29 of the past 33 highs (88%) were in the: 60s (7), 70s (8) and 80s (14). Our most recent 60s high was 60 in 2001. Three highs were in the hot 90s. One high was in the cool 50s (55 in 1983).

In looking back through the years to the first May at O'Hare in 1959, the following instances were notable: In 1971 the high was 82 with a low of 45, a 37 degree spread. In 1970 the low was a warm 68 degrees. In 1964 the high was 69 with a cold low of 34, a 35 degree spread and cool day. In 1963 the high was 74 with a cold low of 41, a 33 degree spread. In 1962 the low was a warm 67 degrees. In 1961 the high was 76 with a cold low of 37, a 39 degree spread.

More recently, there were additional large spreads of 31 degrees in 1984 (70/39) and 31 degrees in 2000 (80/49).


On the cool side, in 1983 the high was the only 50s high for the date at 55 degrees with a low of 45. In 1996 the high was 65 with a low of 36. Five years later, in 2001, the high was 60 with a low of 45. The other cold low was 39 in 1984. Both records were set way back in the 19th century, at a time when the official readings were taken adjacent to Lake Michigan. The record low of 35 was set way back in 1873. The record coolest high of 42 occurred way back in 1889. 31 of the last 33 lows (94%) were in the: 40s (9), 50s (10) and 60s (12). Two lows were in the cold 30s. Prior to 1979, O'Hare had cold lows of 34 in 1964, 37 in 1961 and 41 in 1963.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:47 and sunrise is at 5:20. Sunset is at 20:22 and twilight ends at 20:56. There's a total of 15 hours, 2 minutes of daylight today and 16 hours, 9 minutes between twilights. We gained two minutes of daylight from yesterday. Tomorrow twilight begins at 4:46 and sunrise is at 5:20. The moon is waxing gibbous, having reached first quarter two days ago at 15:16. Illumination was 65% at midnight, will be 71% at noon and 76% at midnight tonight. Moonset was at 1:51 this morning. Moonrise is at 14:55 this afternoon. Moonset is at 2:22 tomorrow morning. Moonlight time is 10 hours, 56 minutes which is 40 minutes shorter than yesterday. 

Spring began on March 12th and runs for 84 days through June 3rd. Warm Spring began on April 13th and runs for 52 days through June 3rd. High temperatures in this period are usually in the 50s, 60s and 70s. Highs in the 80s and 90s occur infrequently. Flag Day is in 15 days.

Tuesday, May 29, 2012

May 29: ORD

Today is May 29th. It's the 150th day of the year. 216 days remain. It's week 22 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 of record was on the south side of Chicago at Midway International Airport (MDW), beginning on Wednesday, July 1, 1942. From Friday, January 1, 1926 through Tuesday, June 30, 1942, the official site was at the University of Chicago. 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 74 and the normal low is 52. I've calculated the 33-year averages at 75 and 53.


On the warm side, in 2006 (O'Hare's warmest May 29th) the high was 91 (O'Hare's warmest high of the date) with a low of 68. In 1991 (O'Hare's second warmest May 29th) the high was 87 with the record warmest low of 71. The former record warmest low of 70 occurred in 1962. In 1987 the high was 89 with a low of 66. In 1999 the high was 86 with a low of 65. The other hot highs were 89 in 1988 and 88 in 2007.
The other warm low was 64 in 1998. The record high of 95 was set back in 1942 at the University of Chicago. 31 of the past 33 highs (94%) were in the: 60s (11), 70s (8) and 80s (12). One high was in the cool 50s and one was in the hot 90s.

In looking back through the years to the first May at O'Hare in 1959, the following instances were notable: In 1978 the high was a hot 88 with a low of 63, a hot day. In 1977 the high was 89 with a low of 64, a hot day. In 1973 the high was a cool 55 with a low of 46, a cool day. In 1972 the low was a warm 64 degrees. In 1971 the high was 75 with a low of 41, a 34 degree spread. In 1970 the high was 85 with a warm low of 67, a warm day. In 1967 the high was a cool 62 degrees. In 1966 the high was 62 with a low of 35, a cool day. In 1965 the high was 55 with a low of 32, a cold day. In 1964 the high was 60 with a low of 36, a cool day. In 1962 the high was 87 with a low of 68, a hot day. 1962 was the year of the former record warmest low of 70. In 1961 the high was 62 with a low of 40, a cool day.

More recently, there was a small spread of seven degrees in 1997 (62/55). There were large spreads of 37 degrees in 1979 (82/45), 33 degrees in 1992 (72/39), 31 degrees in 1985 (75/44) and 30 degrees in 1988 (89/59).

 
On the cool side, in 1984 (O'Hare's second coolest May 29th) we had the only 50s high of 57 with the record-tying low of 37. The record low of 37 was originally set in 1965. In 1996 the high was 60 with a low of 40. Three years earlier, in 1993, the high was 61 with a low of 41. The other cool highs were 62 in 1997, 62 in 2001 and 63 in 1990. The other cold low was 39 in 1992. The record coolest high of 46 occurred way back in 1889, at a time when the official readings were taken adjacent to Lake Michigan. 30 of the last 33 lows (91%) were in the: 40s (12), 50s (10) and 60s (8). Two lows were in the cold 30s and one was in the warm 70s. O'Hare's coolest May 29th was in 1965 as the high was 55 (O'Hare's coolest high of the date) and low of 32. Three consecutive lows (36 in 1964, 32 in 1965 and 35 in 1966) were colder than the record low.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:47 and sunrise is at 5:21. Sunset is at 20:21 and twilight ends at 20:55. There's a total of 15 hours of daylight today and 16 hours, 8 minutes between twilights. We gained a minute of daylight from yesterday. Tomorrow twilight begins at 4:47 and sunrise is at 5:20. The moon is waxing gibbous, having reached first quarter yesterday at 15:16. Illumination was 55% at midnight, will be 60% at noon and 65% at midnight tonight. Moonset was at 1:21 this morning. Moonrise is at 13:45 this afternoon. Moonset is at 1:51 tomorrow morning. Moonlight time is 11 hours, 36 minutes which is 39 minutes shorter than yesterday. 

Spring began on March 12th and runs for 84 days through June 3rd. Warm Spring began on April 13th and runs for 52 days through June 3rd. High temperatures in this period are usually in the 50s, 60s and 70s. Highs in the 80s and 90s occur infrequently. Flag Day is in 16 days. 

Monday, May 28, 2012

May 28: ORD

Today is May 28th. It's the 149th day of the year. 217 days remain. It's week 22 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 of record was on the south side of Chicago at Midway International Airport (MDW), beginning on Wednesday, July 1, 1942. From Friday, January 1, 1926 through Tuesday, June 30, 1942, the official site was at the University of Chicago. 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 74 and the normal low is 52. I've calculated the 33-year averages at 73 and 52.


On the warm side, in 2006 (O'Hare's warmest May 28th) the high was a near-record 92 degrees (until 2012, the record was 93 in 1977) with the record warmest low of 74 (the former record warmest low is 72 in 1941). In 1991 (until 2012, O'Hare's second warmest May 28th) the high was 91 with a low of 69. In 1987 the high was 88 with a low of 68. In 1998 the high was 90 with a low of 60, a 30 degree spread. In 1999 the high was 87 (our most recent 80s high) with a low of 63 (our most recent 60s low). The other warm high was 88 in 1988.
22 of the past 33 highs (67%) were in the: 60s (11) and 70s (11). There were six consecutive 60s & 70s highs from 2000 through 2005. Eight highs (24%) were in the warm: 80s (5) and 90s (3). Our most recent 80s high was 87 in 1999. Three highs (9%) were in the cool 50s. Until 2012, O'Hare's third warmest May 28th was in 1969 (high of 90, low of 67). The other pre-1979 warm high was 88 in 1978. O'Hare's other pre-1979 warm low was 65 in 1959.

In looking back through the years to the first May at O'Hare in 1959, the following instances were notable: In 1978 the high was a hot 88 with a low of 62, a hot day. In 1977 the high was a hot 93 with a low of 56, a 37 degree spread and hot day. 1977 was the year of the record high.
In 1972 the high was a hot 88 degrees. In 1971 the high was 68 with a cold low of 38, a 30 degree spread. In 1970 the high was 80 with a low of 50, a 30 degree spread. In 1969 the high was 90 with a low of 67, a hot day. In 1968 the high was a cool 61 degrees. In 1967 the high was a cool 62 degrees. In 1965 the high was 52 with a low of 38, a cold day. In 1964 the high was a cool 59 with a low of 44, a cool day. In 1959 the high was 84 with a warm low of 65, a warm day.

More recently, there was a small spread of six degrees in 1983 (59/53). There were large spreads of 34 degrees in 1994 (80/46), 33 degrees in 1981 (79/46) and 30 degrees in 1989 (72/42).


On the cool side, in 1984 (O'Hare's second coolest May 28th) the high was 51 (O'Hare's coolest high of the date) with a low of 40. In 1992 the high was 69 with the record low of 33, a 36 degree spread. In 1996 the high was 57 with a low of 46. The other cool highs were 59 in 1983, 60 in 2000, 60 in 2004, 61 in 1985, 62 in 2008 and 62 last year, in 2011. The record coolest high of 47 occurred way back in 1884, at a time when the official readings were taken adjacent to Lake Michigan. 26 of the last 33 lows (79%) were in the: 40s (11) and 50s (15). One low (3%) was in the cold 30s and six (18%) were in the warm: 60s (5) and 70s (1). O'Hare's coolest May 28th was in 1965 as the high was O'Hare's second coolest high for the date of 52 and low of 38. The other pre-1979 cold low was 38 in 1971.  

There was an instance of back-to-back years in which temperatures were just about as opposite as they can be. In 1991 the high was 91 with a low of 69,  overall 17 degrees ABOVE normal. Then in 1992 the high was 69 with a low of 33, overall 12 degrees BELOW normal.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:48 and sunrise is at 5:21. Sunset is at 20:20 and twilight ends at 20:54. There's a total of 14 hours, 59 minutes of daylight today and 16 hours, 6 minutes between twilights. We gained a minute of daylight from yesterday. Tomorrow twilight begins at 4:47 and sunrise is at 5:21. The moon reaches first quarter today at 15:16. Illumination was 44% at midnight, will be 49% at noon and 55% at midnight tonight. Moonset was at 0:52 this morning. Moonrise is at 12:37 this afternoon. Moonset is at 1:21 tomorrow morning. Moonlight time is 12 hours, 15 minutes which is 37 minutes shorter than yesterday. 

Spring began on March 12th and runs for 84 days through June 3rd. Warm Spring began on April 13th and runs for 52 days through June 3rd. High temperatures in this period are usually in the 50s, 60s and 70s. Highs in the 80s and 90s occur infrequently. Memorial Day is today. Flag Day is in 17 days. 

Sunday, May 27, 2012

May 27: ORD

Today is May 27th. It's the 148th day of the year. 218 days remain. It's week 21 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 of record was on the south side of Chicago at Midway International Airport (MDW), beginning on Wednesday, July 1, 1942. From Friday, January 1, 1926 through Tuesday, June 30, 1942, the official site was at the University of Chicago. 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 74 and the normal low is 52. I've calculated the 33-year averages at 72 and 50.


On the warm side, in 1987 (until 2012, O'Hare's warmest May 27th) the high was 88 with a low of 68 (until 2012, O'Hare's warmest low of the date). Four years later, in 1991 (until 2012, O'Hare's second warmest May 27th and tied with 1978), the high was 88 with a low of 66. The other warm high was 87 in 2006. The record high of 94 and record warmest low of 75 were set on the same hot day way back in 1911
, at a time when the official readings were taken adjacent to Lake Michigan. That record high of 94 was broken in 2012 as the high reached 97 degrees. 23 of the past 33 highs (70%) were in the: 60s (12) and 70s (11). O'Hare recorded six consecutive 60s & 70s highs from 1981 through 1986. There were another six consecutive 60s & 70s highs from 2000 through 2005. Our most recent 60s highs were 66 in 2000 and 61 in 2001. Seven highs (21%) were in the warm 80s. Three highs (9%) were in the cool 50s. Until 2012, 1978 was tied with 1991 as the second warmest May 27th. In 1978 the high was 88 with a low of 66. The other pre-1979 hot days occurred in 1969 (high of 87, low of 63) and 1959 (high of 83, low of 66). Until 2012, O'Hare's warmest May 27th highs were 88 degrees, occurring in 1978, 1987 and 1991. Until 2012, O'Hare's second warmest lows were 66 degrees, in 1959, 1978 and 1991. 

As of 4:00 PM on March 27, 2012, the National Weather Service had noted the following highs: 99 at Rockford, 97 at: O'Hare, Aurora, Midway, the Chicago lakefront and Kankakee. It had reached 96 at West Chicago, Romeoville (Nat'l Weather Svc) and DeKalb. Joliet had reached 95 degrees.  

In looking back through the years to the first May at O'Hare in 1959, the following instances were notable: In 1978 the high was 88 with a low of 66, a hot day. In 1976 the high was 77 with a low of 46, a 31 degree spread. In 1971 the low was a cold 38 degrees. In 1970 the high was a cool 61 degrees. In 1969 the high was 87 with a low of 63, a hot day. In 1968 the high was a cool 61 with a low of 54, a seven degree spread. In 1966 the high was 85 with a low of 54, a 31 degree spread. In 1963 the high was a cool 60 degrees. In 1962 the high was a cool 59 degrees. In 1961 the high was 70 with a cold low of 34, a 36 degree spread. In 1959 the high was 83 with a warm low of 66, a warm day.

More recently, there was a small spread of six degrees in 1996 (54/48). There were additional large spreads of 35 degrees in 1999 (81/46), 33 degrees in 1980 (85/52), 33 degrees in 1998 (83/50) and 32 degrees in 1994 (67/35).

 
On the cool side, in 2008 (O'Hare's coolest May 27th) the high was 50 (O'Hare's coolest high of the date) with a low of 42. In 1992 the high was 63 with the record low of 33, a 30 degree spread. Last year, in 2011, the high was 58 with a low of 40. The other cold low was 35 in 1994. The other cool highs were 54 in 1996, 61 in 2001 and 62 in 1984. The record coolest high of 49 occurred way back in 1895, at a time when the official readings were taken adjacent to Lake Michigan. 28 of the last 33 lows (85%) were in the: 40s (16) and 50s (12). Two lows were in the cold 30s and three were in the warm 60s.

There was an instance of back-to-back years in which temperatures were just about as opposite as they can be. In 1991 the high was 88 with a low of 66,  overall 15 degrees ABOVE normal. Then in 1992 the high was 63 with a low of 33, overall 14 degrees BELOW normal.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:49 and sunrise is at 5:22. Sunset is at 20:20 and twilight ends at 20:53. There's a total of 14 hours, 58 minutes of daylight today and 16 hours, 4 minutes between twilights. We gained two minutes of daylight from yesterday. Tomorrow twilight begins at 4:48 and sunrise is at 5:21. The moon is waxing crescent, heading towards the first quarter tomorrow at 15:16. Illumination was 33% at midnight, will be 39% at noon and 44% at midnight tonight. Moonset was at 0:23 this morning. Moonrise is at 11:31 this morning. . Moonset is at 0:52 tomorrow morning. Moonlight time is 12 hours, 52 minutes which is 41 minutes shorter than yesterday. 

Spring began on March 12th and runs for 84 days through June 3rd. Warm Spring began on April 13th and runs for 52 days through June 3rd. High temperatures in this period are usually in the 50s, 60s and 70s. Highs in the 80s and 90s occur infrequently. Memorial Day is tomorrow. 

May 26: ORD

Today is May 26th. It's the 147th day of the year. 219 days remain. It's week 21 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 of record was on the south side of Chicago at Midway International Airport (MDW), beginning on Wednesday, July 1, 1942. From Friday, January 1, 1926 through Tuesday, June 30, 1942, the official site was at the University of Chicago. 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 73 and the normal low is 51. I've calculated the 33-year averages at 70 and 49.


On the warm side, two years ago, in 2010 (tied with 1967 as O'Hare's warmest May 26th), the high was 87 with a low of 66. In 1985 the high was 89 with a low of 62. In 1991 the high was 82 with a low of 69 (O'Hare's warmest low of the date). In 1987 the high was 86 with a low of 61. The record high of 94 was set back in 1911 and the
record warmest low of 75 occurred in 1914. Both records were set at a time when the official readings were taken adjacent to Lake Michigan. 22 of the past 33 highs (67%) were in the: 60s (9) and 70s (13). O'Hare recorded six consecutive highs in the 60s & 70s from 1979 through 1984. Six highs (18%) were in the warm 80s. Five highs (15%) were in the cool: 40s (1) and 50s (4). There seems to be a distinction in terms of the eras of the 80s highs. The first three happened between 1985 and 1991. The second three happened between 2006 and two years ago (2010). 1967 is tied with 2010 as the warmest May 26th with a high of 92 (O'Hare's warmest high of the date) and low of 61.

In looking back through the years to the first May at O'Hare in 1959, the following instances were notable: In 1978 the high was 87 with a low of 65, a hot day. In 1971 the high was a cool 54 with a low of 43, a cool day. In 1969 the high was 74 with a cold low of 39, a 35 degree spread. In 1967 the high was a hot 92 with a low of 61, a 31 degree spread and hot day. In 1966 the high was 82 with a low of 49, a 33 degree spread. In 1965 the low was a warm 63 degrees. In 1962 the high was a cool 59 degrees. In 1961 the high was 47 with a low of 36, a cold day and year of the record coolest high. In 1959 the high was 84 with a warm low of 64, a warm day.

More recently, there were large spreads of 36 degrees in 1988 (78/42), 36 degrees in 2002 (73/37), 34 degrees in 2008 (81/47), 33 degrees in 1993 (78/45), 31 degrees in 1979 (70/39) and 31 degrees in 1998 (78/47).


On the cool side, in 1992 (O'Hare's second coolest May 26th) the high was 53 with a low of 35. Last year, in 2011, the high was 49 with a low of 43. This was only the second 40s high in O'Hare's history for the date (just 3.7% of the highs in its history and 2.8% in Chicago's history). In 1983 the high was 60 with the record low of 34. In 2001 the high was 57 with a low of 38. In 1994 the high was 59 with a low of 37. In 1997 the high was 55 with a low of 46. The other cool high was 60 in 1996. The other cold lows were 37 in 2002 and 39 in 1979. The record coolest high of 48 occurred in 1961. 22 of the last 33 lows (67%) were in the: 40s (14) and 50s (8). There were six consecutive 40s & 50s lows from 1995 through 2000. Five of the six (83%) were in the 40s. Six lows (18%) were in the cold 30s. Our most recent 30s low was 37 in 2002. Five lows (15%) were in the warm 60s. O'Hare's coldest May 26th was in 1961 as the high was 47 (O'Hare's coolest high of the date) with a low of 36. The other pre-1979 cold low was 39 in 1969.

There were two instances of back-to-back years in which temperatures were just about as opposite as they can be. In 1991 the high was 82 with a low of 69, overall 13.5 degrees ABOVE normal. Then in 1992 the high was 53 with a low of 35, overall 18 degrees BELOW normal. In the second instance, in 2010 the high was 87 with a low of 66, overall 14.5 degrees ABOVE normal. Then in 2011 the high was 49 with a low of 43, overall 16 degrees BELOW normal.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:49 and sunrise is at 5:23. Sunset is at 20:19 and twilight ends at 20:52. There's a total of 14 hours, 56 minutes of daylight today and 16 hours, 3 minutes between twilights. We gained a minute of daylight from yesterday. Tomorrow twilight begins at 4:49 and sunrise is at 5:22. The moon is waxing crescent, heading towards the first quarter in two days at 15:16. Illumination was 24% at midnight, will be 29% at noon and 33% at midnight tonight. Moonrise was at 10:27 this morning. Moonset is at 0:23 tomorrow morning. Moonrise is at 11:31 tomorrow morning. Moonlight time is 13 hours, 33 minutes which is 54 minutes shorter than yesterday. 

Spring began on March 12th and runs for 84 days through June 3rd. Warm Spring began on April 13th and runs for 52 days through June 3rd. High temperatures in this period are usually in the 50s, 60s and 70s. Highs in the 80s and 90s occur infrequently. Memorial Day is in two days. 

Friday, May 25, 2012

May 25: ORD

Today is May 25th. It's the 146th day of the year. 220 days remain. It's week 21 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 of record was on the south side of Chicago at Midway International Airport (MDW), beginning on Wednesday, July 1, 1942. From Friday, January 1, 1926 through Tuesday, June 30, 1942, the official site was at the University of Chicago. 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 73 and the normal low is 51. I've calculated the 33-year averages at 69 and 49.


On the warm side, two years ago, in 2010 (O'Hare's warmest May 25th), the high was 88 with a low of 69 (O'Hare's warmest low of the date). Four years earlier, in 2006, the high was 75 with a low of 64. The other warm high was 84 in 1985. The record high of 94 was set back in 1911 and the
record warmest low of 72 occurred back in 1914. Both records were set at a time when the official readings were taken adjacent to Lake Michigan. 22 of the past 33 highs (67%) were in the: 60s (12) and 70s (10). O'Hare recorded seven consecutive 60s & 70s highs from 2003 through 2009. Four highs (12%) were in the warm 80s. Seven highs (21%) were in the cool 50s. Our most recent 50s highs were 59 in 2001 and 57 in 2002. O'Hare's second warmest May 25th was in 1977 as the high was 90 (O'Hare's warmest high of the date) with a low of 62. The third warmest was in 1965 (high of 82, low of 67).

In looking back through the years to the first May at O'Hare in 1959, the following instances were notable: In 1978, the high was 82 with a low of 52, a 30 degree spread. In 1977 the high was a hot 90 with a low of 62, a hot day. In 1975 the low was a warm 66 degrees. In 1972 the high was a warm 85 degrees. In 1971 the high was a cool 60 degrees. In 1967 the high was 84 with a low of 49, a 35 degree spread. In 1965 the high was 82 with a warm low of 67, a warm day. In 1964 the high was 80 with a low of 48, a 32 degree spread. In 1961 the low was a cold 39 degrees.

More recently, there was a small spread of seven degrees in 1990 (60/53). There were large spreads of 34 degrees in 1985 (84/50), 34 degrees in 2008 (78/44), 31 degrees in 1981 (80/49) and 30 degrees in 1980 (82/52).

 
On the cool side, in 1992 (O'Hare's coolest May 25th) the high was 51 (O'Hare's coolest high of the date) with the record low of 32. In 1988 the high was 59 with a low of 37. Five years prior, in 1983, the high was 59 with a low of 38. In 2002 the high was 57 with a low of 41. In 1997 the high was 54 with a low of 45. In 1996 the high was 56 with a low of 45. The other cool highs were 59 in 2001 and 60 in 1990. The record coolest high of 44 occurred way back in 1893, at a time when the official readings were taken adjacent to Lake Michigan. 28 of the last 33 lows (85%) were in the: 40s (14) and 50s (14). Three lows were in the cold 30s and two were in the warm 60s. The 30s lows occurred between 1983 and 1992 while the 60s lows occurred between 2006 and 2010. O'Hare's only 30s low prior to 1983 was 39 degrees in 1961.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:50 and sunrise is at 5:23. Sunset is at 20:18 and twilight ends at 20:51. There's a total of 14 hours, 55 minutes of daylight today and 16 hours, 1 minute between twilights. We gained two minutes of daylight from yesterday. Tomorrow twilight begins at 4:49 and sunrise is at 5:23. The moon is waxing crescent. Illumination was 16% at midnight, will be 20% at noon and 24% at midnight tonight. Moonrise was at 9:24 this morning. Moonset is at 23:51 tonight. Moonrise is at 10:27 tomorrow morning. Moonlight time is 14 hours, 27 minutes which is 25 minutes shorter than yesterday. 

Spring began on March 12th and runs for 84 days through June 3rd. Warm Spring began on April 13th and runs for 52 days through June 3rd. High temperatures in this period are usually in the 50s, 60s and 70s. Highs in the 80s and 90s occur infrequently. Memorial Day is in three days.

May 24: ORD

Today is May 24th. It's the 145th day of the year. 221 days remain. It's week 21 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 of record was on the south side of Chicago at Midway International Airport (MDW), beginning on Wednesday, July 1, 1942. From Friday, January 1, 1926 through Tuesday, June 30, 1942, the official site was at the University of Chicago. 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 73 and the normal low is 51. I've calculated the 33-year averages at 70 and 50.


On the warm side, two years ago, in 2010 (O'Hare's warmest May 24th), the high was 91 (along with the high of 91 in 1977, O'Hare's warmest highs of the date) with the new record warmest low of 70. In 1991 the high was 85 with the former record warmest low of 68. In 1933 the low was 67 which is another former record warmest low. In 1989 the high was 86 with a low of 65. In 2007 the high was 88 with a low of 63. The record high of 93 was last tied in 1950 at Midway, having
originally been set in 1921. 21 of the past 33 highs (64%) were in the: 60s (11) and 70s (10). There were nine consecutive highs in the 60s & 70s from 1978 through 1986. Seven of these (78%) were in the 70s. Seven highs (21%) were in the warm: 80s (6) and 90s (1). Five highs (15%) were in the cool: 40s (1) and 50s (4). O'Hare's second warmest May 24th was in 1977 as the high was 91 (it was also 91 two years ago in 2010) with a low of 64.

In looking back through the years to the first May at O'Hare in 1959, the following instances were notable: In 1977 the high was 91 with a low of 64, a hot day. In 1976 the high was a cool 60 degrees. In 1975 the high was a warm 85 with a low of 62, a warm day. In 1972 the high was a hot 86 with a low of 54, a 32 degree spread. In 1965 the high was 83 with a low of 53, a 30 degree spread. In 1961 the high was 80 with a low of 45, a 35 degree spread. In 1960 the high was a cool 60 degrees.

More recently, there were large spreads of 34 degrees in 1985 (78/44), 32 degrees in 1983 (76/44), 31 degrees in 1997 (84/53) and 31 degrees in 2006 (80/49).


On the cool side, in 1992 (O'Hare's coolest May 24th) the high was 46 (O'Hare's coolest high of the date) with the record low of 34. In 2001 the high was 60 with a low of 42. Two years earlier, in 1999, the high was 54 with a low of 48, a six degree spread. Two decades earlier, in 1979, the high was 62 with a low of 40. The other cool highs were 61 in 1982, 57 in 1995, 56 in 1987 and 56 in 1996. The record coolest high of 44 occurred back in 1925, at a time when the official readings were taken adjacent to Lake Michigan. 28 of the last 33 lows (85%) were in the: 40s (18) and 50s (10). One low was in the cold 30s. Four lows were in the warm: 60s (3) and 70s (1).

There was an instance of back-to-back years in which temperatures were just about as opposite as they can be. In 1991 the high was 85 with a low of 68,  overall 14.5 degrees ABOVE normal. Then in 1992 the high was 46 with a low of 34, overall 22 degrees BELOW normal.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:51 and sunrise is at 5:24. Sunset is at 20:17 and twilight ends at 20:50. There's a total of 14 hours, 53 minutes of daylight today and 15 hours, 59 minutes between twilights. We gained two minutes of daylight from yesterday. Tomorrow twilight begins at 4:50 and sunrise is at 5:23. The moon is waxing crescent. Illumination was 10% at midnight, will be 13% at noon and 16% at midnight tonight. Moonrise was at 8:24 this morning. Moonset is at 23:16 tonight. Moonrise is at 9:24 tomorrow morning. Moonlight time is 14 hours, 52 minutes which is 17 minutes shorter than yesterday. 

Spring began on March 12th and runs for 84 days through June 3rd. Warm Spring began on April 13th and runs for 52 days through June 3rd. High temperatures in this period are usually in the 50s, 60s and 70s. Highs in the 80s and 90s occur infrequently. Memorial Day is in four days.