Friday, July 20, 2012

Who Remembers the “Summer of ’69?”

Image from NASA 
10:56 PM EDT 7/20/12 (Forecaster Mike) – Exactly 43 years ago, it was “One giant leap for mankind” as  As Advisor Keith noted earlier tonight, it was 10:56 PM on a (muggy) July 20 in 1969 when NASA Astronaut Neil Armstrong first stepped onto the moon. Who remembers the "Summer of '69"? No I don't mean the 1985 song by Bryan Adams, but rather the year of the first manned lunar landing! Less than a month later would bring one of the most infamous hurricanes of all time: Camille. We took a look back into the climate record and found some sharp differences, as well as interesting similarites between 2012 and 1969.


EL NINO SOUTHERN OSCILLATION – While 1969 was coming from a very different place compared to 2012, the projections look pretty similar! The winter of 1968-1969 was coming from a Moderate El Nino, which means above average temperatures in the equatorial Pacific. However, the winter of 2011-2012 was the direct opposite, with a Moderate La Nina weakening through the spring of 2012. El Nino conditions actually still persisted through the middle of the summer 1969, but the equatorial temperatures are currently climbing significantly through the neutral ranges of temperatures this year. In the winter of 1969-1970, we went right back to El Nino conditions, and the projections for the fall of 2012 and the winter 2012-13 are increasingly pointing to El Nino conditions developing.

Hurricane seasons to date from Wikipedia

HURRICANE SEASON – July 20th still lies at the very beginning of hurricane season, but the seasons of 2012 and 1969 to date are actually very similar. Both seasons saw four tropical systems develop before July 20th, but the 1969 storms were all tropical depressions with winds of under 39 MPH. However, the 2012 storms all developed into tropical storms or in the case of Chris, a minimal hurricane. Also, two storms developed in May of each respective year and June saw the other two. We can only hope that these similarities end very soon, because we certainly don’t want any repeats of the devastating impact that Camille dealt in August of 1969.

June Temperature Comparison

TEMPERATURE COMPARISON – As far as the temperatures of summer 1969 go compared to the summer of 2012, they could not be more different! Especially for the month of June, almost every state that was above average for June of 1969 was below average in 2012 and nearly every state that was below normal in 1969 was above normal in 2012! This could be attributed to the fact that the Pacific was cooling in spring and early summer of 1969, while it was warming significantly in 2012! As we head into July, the temperatures become less different, which may be expected because of the fact that the temperatures in the Pacific became closer together into the seventh month. 

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