October 2016 Summary – Wetter and Warmer Than Average

Blue Hill Observatory
October 2016 Summary:

The month was the wettest of the year so far and warmer than average. The 24-hour mean temperature for the month of 53.2 deg F was 2.1 degrees warmer than the 120-year average for October and nearly two degrees warmer than the 1981-2010 30-year average. The highest temperature for the month was 79F on the 19th, and the low temperature of 28F occurred on the 27th. There were 7 cooling degree days during October, which raised the seasonal total to 901. This is the second highest seasonal cooling degree day total since at least since 1960.  October brought a total of 7.04 inches of precipitation, which was more than three inches greater than the long-term 120-year average and two and a third inches more than the 30-year mean. This was the wettest month since December 2014. The greatest amount in 24 hours in October was 1.89 inches on the 9th, which was in part associated with moisture from the remains of dissipating Hurricane Matthew. That day was one of three calendar days during the month with more than one inch of rainfall. On the 21st a total of 1.60 inches was recorded, and nearly one and a half inches of this total fell in about 90 minutes during the only thunderstorm in October. The mean wind speed was 11.8 mph, which tied for the second lowest mean wind speed for October, and the prevailing direction was from the west. The peak gust was 47 mph from the west on the 23rd. October was sunnier than average with 59 percent of the possible bright sunshine being recorded, which is 3 percent more than the long-term mean for the month.

BHO Greatest Number Seasonal Cooling Degree Days, (1960-2016):

1) 916 in 2010
2) 901 in 2016 (through October)
3) 811 in 2015
4) 805 in 1999
5) 780 in 2005

BHO Lowest October Mean Wind Speed, mph (1885-2016):

1) 11.2 in 2013
2) 11.8 in 1997
   11.8 in 2016
4) 11.9 in 1994
   11.9 in 2004
6) 12.0 in 2007

Mike Iacono
Chief Scientist
Blue Hill Observatory