April 2015 Wind: A historical perspective

Many have inquired as to why this month as been so windy.  The answer… it is April.  Climatologically, March, April and November are the three windiest months of the year.  Yet, just because this is a windy time of year, has April 2015 been exceptionally windy?   Long term wind data is only available at some locations.  The North Dakota Agricultural Weather Network (NDAWN) has been recording wind at 3 meters (10 feet) since the early 1990s.  Below is the overall average of the network since 1995 for the April 1 through April 23 time period.  Some stations have been added during this time frame, but using the combined average gives an overview of which years the wind speeds were a bit higher and lower than other years.  Since 1995, the NDAWN average April wind speed has been 10.3 mph.  So far this month the average has been around 10.8 mph, so slightly above average, yet far short of the record of 11.8 mph set back in April of 2005.

AprilWindAverageNDAWN

 

Hector Int’l Airport has wind records dating back to 1932.  Wind speed and direction at airports has been historically measured at 10 meters (33 feet).  That increase in height will make wind speed measurements much higher than those kept at the 3 meters height at the NDAWN stations.   As of yesterday (April 23) the average wind speed for this month at Hector Int’l has been 14.0 mph.   The average wind speed for the first 23 days is 13.6 mph which is just slightly above the average just like the data for the all the sensors of the NDAWN network.  That 14.0 mph average would rank the first 23 days of April as the 24th windiest such period out of the 77 years of day.

This would place this month into the none scientific category as “noticeably windier” as the wind has just been enough above average to differentiate it from other years, yet the caveat to this is short term memories and the reality that wind is almost always a noticeable factor this time of year.  Below is a graph of the average wind speed from maximum to minimum for the top 24 windiest April 1 to April 23 time periods.

Average Wind Speed April 1-23

Year

19.2 1961
18.5 1954
18.3 1956
18.3 1960
17.1 1957
16.9 1955
16.7 1958
16.6 1943
16.4 1950
16.2 1934
15.9 1959
15.5 1949
15.1 1951
15.1 1942
15.0 1948
14.9 1937
14.8 1990
14.8 1945
14.7 1989
14.3 1941
14.2 1946
14.2 1953
14.1 1991
14.0 2015

If you need data to support your “feeling” that this month has been windy, you have it, but generally speaking this month really has not been all that much more windy than other Aprils in the recent past.

 

Daryl Ritchison