DOES ANA EXIST IF THIS IS 1980?

The official start date for what is considered "Hurricane Season" is June 1. The season's last day is November 30. It's in this time frame that conditions become the most conducive for tropical activity to occur. In fact, since 1851, 97% of the systems that have reached at least tropical storm strength, have occured between June 1 and November 30. But Mother Nature doesn't adhere to dates on a calendar, and as a result, there have been numerous tropical systems that have popped up outside of this official "season".

The month of May, the month immediately preceding the official start, is when we see the majority of these "off-season" systems as conditions begin to improve for tropical development as we near the official "season". 64% of the off-season activity occurs in May. In fact, with the formation of Ana a couple of days ago, there has been a storm form in May for 7 straight years. This has prompted discussion of moving the start of the season up a couple of weeks to May 15. The NHC has already moved up the start of it's daily reports to that date starting this year. Still, May lags far behind the month of June in tropical activity. Since 1851 there's been 53 tropical storms in May, with only 5 of those becoming hurricanes. June has had 98 tropical storms with 38 of those becoming hurricanes in that time frame. So I don't think May is quite ready for prime time.

The month of December, the month immediately following the end of the season, would be 2nd behind May for the most off-season tropical activity, with more than 2/3 fewer storms than May, but there are records of tropical systems in every month of the year.

4 years ago Tropical Storm Arlene formed in April. The year before that we saw Hurricane Alex form in January. JANUARY! Alex is one of 2 hurricanes to have formed in January. The other occured in 1938. The Groundhog Day tropical storm of 1952 is the only storm on record to form in February, and a category 2 hurricane in 1908 is the only known March storm. And most of this was before we had the advanced satellite technology we have today that allows us to see every single inch of the ocean. Back then we had to rely on ships that happened to pass by when these storms occured.

That brings me to the hyper active period of tropical systems we've seen in the last couple of decades. From 1980 to 2000, there were an average of 10.3 storms of at least tropical storm strength that formed every season. From 2001 to 2020 that has increased to 16.5 per season. The advancement in technology has played a significant role in these increased numbers. Even with full coverage satellite imagery of the entire tropics in the 80's and 90's, it didn't compare to the tools used today to estimate the strength and structure of these systems. For example, in 1980, would anybody have even noticed the tiny system that became Tropical Storm Ana a few days ago?


Some of the smaller storms we see out there are usually still about 200-250 miles wide. Tropical Storm Ana was only about 65 miles wide at it's peak. I doubt the technology of the 80's would have even given this system a 2nd thought, but it doesn't slip by in today's world. Ana started out being classified as a subtropical storm, meaning it had characteristics of a typical cold core low we're used to seeing on a weather map as a big red L with fronts attached to it, and the banding and centralized features of a warm core tropical system.

It wasn't until 2002 that the NHC started assigning names to these subtropical systems that reached the tropical storm threshold of winds greater than 39 mph. Could this also be attributed to the rise in the average numbers of storms the last 20 years? Not if you consider that since 2002 there's only been 6 named subtropical storms. 6 that haven't transitioned to tropical, that is. Ana made the transition from subtropical to tropical. Several others have done the same over the years.

It's hard to say if Ana would have been classified in 1980. It most definitely would not have been before 1950. But today, nothing gets by, and that advancement in technology has played a part in the increase of tropical activity, even since the 80's when we still had the eyes in the sky. Not saying that we aren't in a hyper active period now, we most definitely are, but the technology to not only spot these systems, but to analyze their structure from above, certainly helps get some of these storms named when they might have been left out as little as a couple of decades ago. Especially those out in the middle of nowhere like Ana.

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