April 2019 Summary – Sixth Wettest and Sixth Cloudiest on Record
Blue Hill Observatory
April 2019 Summary:
April was warmer than average, though it ended cool, with much above average rainfall and below average sunshine. The 24-hour adjusted mean temperature for the month of 47.3 deg F was 2.6 degrees warmer than the 120-year average for April and 1.0 degrees warmer than the 1981-2010 30-year average. The average maximum temperature of 57.2 deg F was about a degree above normal, and the average minimum temperature of 39.3 deg F was about two degrees above normal. The highest temperature for the month was 71F on the 13th, 14th, and 19th, and the lowest temperature was 27F on the 2nd and 5th. Precipitation was frequent during April and totaled 8.14 inches, which was about four inches more than the long-term 120-year average and three and a half inches more than the 30-year mean. The month was the sixth wettest April on record and the wettest since 2007. The greatest amount in 24 hours was 3.00 inches on the 22nd-23rd. The 2.60 inches on the 22nd was the fourth wettest calendar day ever observed in April. There were 20 days with measurable precipitation during the month, which tied the record for April, and this number tied for the third most ever observed in any month. Only a trace of snow was recorded, on the 10th, which left the seasonal total at 47.6 inches, more than a foot below average. The mean wind speed was 13.6 mph, and the prevailing direction was from the south. A peak gust of 54 mph from the west occurred during rain on the 3rd. April started very sunny, but the last 23 days were exceptionally cloudy. During this period a total of nine days had no bright sunshine. The month had a total of only 137.3 hours of sunshine, or 35 percent of the possible bright sunshine, which was 14 percent below the long term average of 49 percent. This made April the sixth cloudiest on record.
BHO Greatest April Precipitation, inches (1886-2019):
1) 10.37 in 1987
2) 9.38 in 2004
3) 8.71 in 1929
4) 8.68 in 2007
5) 8.53 in 1904
6) 8.14 in 2019
7) 7.57 in 1935
7.57 in 1983
9) 7.31 in 1901
BHO Greatest April Calendar Day Precipitation, inches (1886-2019):
1) 3.47 on April 1, 2004
2) 3.18 on April 21, 1991
3) 2.63 on April 16, 2018
4) 2.60 on April 22, 2019
5) 2.51 on April 24, 1898
2.51 on April 13, 2004
6) 2.45 on April 16, 1929
7) 2.41 on April 28, 1904
8) 2.40 on April 10, 1935
BHO Greatest April Number of Days Measurable Precipitation (1886-2019):
1) 20 in 1912
20 in 1929
20 in 2019
4) 19 in 1901
19 in 1921
6) 18 in 1953
18 in 1987
8) 17 in 1916
17 in 1955
BHO Greatest Monthly Number of Days Measurable Precipitation (1886-2019):
1) 22 in December 1972
2) 21 in May 1888
3) 20 in July 1906
20 in April 1912
20 in October 1913
20 in June 1916
20 in April 1929
20 in January 1950
20 in May 2005
20 in April 2019
BHO Lowest April Sunshine, hours (1886-2019):
1) 82.6 in 1901 [21%]
2) 121.1 in 1987 [31%]
3) 121.7 in 1988 [31%]
4) 131.6 in 1983 [34%]
5) 132.2 in 1921 [34%]
6) 137.3 in 2019 [35%]
7) 138.1 in 1939 [36%]
8) 140.7 in 1955 [36%]
9) 141.1 in 2000 [36%]
Mike Iacono
Chief Scientist
Blue Hill Observatory
