August 2022 Summary – Second Warmest on Record

Blue Hill Observatory August 2022 Summary: 

August followed the lead of July and was exceedingly warm with less rainfall and more sunshine than expected. The approximated 24-hour mean temperature for the month of 73.9 deg F was 5.6 degree warmer than the 1891-2020 130-year average for August, and it was 3.6 degrees warmer than the 1991-2020 30-year average. August 2022 was both the second warmest August on record and the tenth warmest month ever observed at Blue Hill. The average maximum temperature of 85.8 deg F was 5.6 degrees warmer than the 30-year normal, and it was the warmest on record for August by a wide margin. The average minimum temperature of 65.0 deg F was 2.4 degrees warmer than the 30-year normal, and it tied as the third warmest on record. The warmth peaked during a six-day heat wave on August 4th-9th that ended with the highest temperature for the month of 97F on the 8th and 9th. This heat wave was one of the ten longest ever recorded at Blue Hill since 1885, and for the first time on the Blue Hill record it was the second heat wave of six days or longer to occur in a single year. Daily record high temperatures were tied or surpassed on the 4th, 6th, 7th, 8th and later in the month on the 20th. There were nine 90-degree days during August, which tied for the third most for the month. For the year to date there have been 19 90-degree days, which already ranks as the fifth most for any year on record. The warmth was also reflected in the 329 total cooling degree days during August, which was a new record for the month. The total precipitation was only 2.39 inches, which was 1.52 inches less than the 30-year normal. The greatest rainfall in 24 hours was 0.83 inches on the 22nd-23rd. For the six months from March to August, the total precipitation was just 13.44 inches, which was about half of the 30-year average rainfall for this period, and this total tied as the 4th driest on record for these six months. There were six thunderstorm days during August, which was two more than average. The mean wind speed for August was 10.0 mph, and the prevailing wind direction was from the southwest. The highest wind gust was 44 mph from the northwest on the 18th. August sunshine was much above average with 269.2 hours of bright sunshine, or 65 percent of possible, which was six percent more than the long-term average for August. 

BHO Highest Monthly 24-Hour Adjusted Mean Temperature, deg F (1885-2022):

1) 75.3 in July 2022
2) 75.1 in July 2010
3) 74.9 in July 1952
4) 74.5 in July 2019
5) 74.1 in July 1994
   74.1 in July 2013
   74.1 in August 2016
8) 74.0 in July 2011
   74.0 in July 2016
10) 73.9 in August 2022

BHO Highest August 24-Hour Adjusted Mean Temperature, deg F (1885-2022):

1) 74.1 in 2016
2) 73.9 in 2022

3) 73.4 in 2018
4) 72.6 in 2012
   72.6 in 2021
6) 72.5 in 1988
7) 72.4 in 2015

BHO Highest August Average Maximum Temperature, deg F (1885-2022):

1) 85.8 in 2022
2) 85.1 in 2016
3) 83.2 in 2005
4) 83.1 in 1949
5) 82.6 in 2015
6) 82.5 in 1988
   82.5 in 2002
   82.5 in 2012
   82.5 in 2020

BHO Highest August Average Minimum Temperature, deg F (1885-2022):

1) 66.4 in 2018
2) 65.4 in 2021
3) 65.0 in 2016
   65.0 in 2022
5) 64.9 in 2001
6) 64.6 in 2012

BHO Highest August Number of Cooling Degree Days (1885-2022):

1) 329 in 2022

2) 318 in 2016
3) 289 in 1988
4) 277 in 2002
5) 274 in 2005
6) 273 in 2012
7) 272 in 2015

BHO Longest Heat Waves (1885-2022):

1) 9 days, Aug 11-19, 2002
2) 8 days, Aug 10-17, 1944
3) 7 days, Jul 22-28, 2016
4) 6 days, Aug 28 – Sep 2, 1953
   6 days, Jul 24-29, 1963
   6 days, Jul 16-21, 1977
   6 days, Jul 6-11, 1988
   6 days, Jul 16-21, 1991
   6 days, Jul 15-20, 2013
   6 days, Jul 19-24, 2022

   6 days, Aug 4-9, 2022

BHO Highest August Number of 90-Degree Days (1885-2022):

1) 13 in 2002
2) 10 in 1944
3) 9 in 1928
   9 in 2022

5) 8 in 1949
6) 7 in 1959
   7 in 1988

Mike Iacono
Chief Scientist
Blue Hill Observatory