ACE for Southern Hemisphere Way Down, Could that Impact the North Atlantic?

Chief Meteorologist Mike Buresh and I were chatting about how the southern hemisphere tropical activity is way down this year.

So– I was up way early to fill in for our morning show on Friday and looked up the stats for ACE (Accumulated Cyclone Energy) for the southern hemisphere.

If you haven’t heard of ACE before… here is the definition from NOAA.

“The ACE index is a wind energy index, defined as the sum of the squares of the maximum sustained surface wind speed (knots) measured every six hours for all named storms while they are at least tropical storm strength.”

Here is what I found:

ACE Southern Hemisphere March 2, 2017. Source:

You’ll notice nothing for us (typical) yet in the north Atlantic. However, we already had Alex last January by this time in 2016 – ACE ~ 3.6. For comparison — Hurricane Matthew in October 2016 racked up an ACE of 48.47.

The current ACE is only 16% of average for the southern hemisphere of our planet.

Colorado State University has  a great real time tropical stats website for reference. The black line below represents the average as we go through the year. The blue line is the observed ACE through March 2, 2017.

Graph of southern hemisphere ACE from Colorado State University.

Again, you can see the big departure from average.

The Earth is always trying to “balance itself out.” This constant attempt to balance is why we have “weather.”

So– with the lack of areas of low pressure tropical cyclones in the southern hemisphere… Mike and I were asking to each other… could that lead to a “balancing out” in the northern hemisphere for the 2017 hurricane season?

Lets hope the anomalously warm Atlantic, Gulf of Mexico, and Caribbean Sea are not an indication. The Atlantic hurricane season is less than 3 months away. Maps here: First Alert Hurricane Center.

Sea Surface Temperature anomaly for March 2, 2017. Source:

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