Most groups that forecast the Atlantic Hurricane season put out their earliest prognostications in April, especially Colorado State University, the Weather Channel, Accuweather, Weather Bell and Houston’s Weather Research Center. NOAA waits until the end of May. Why the wait? These groups prefer to watch the climate for different signals, including trade wind strength, El Niño strength or La Niña being weak. Sea surface water temperatures obviously play an important role (especially if they are coming in warmer than normal) along with global air pressures. April seems to be a good month to see how it’s all shaking out.
One group, from the United Kingdom, has been forecasting early since 2003 and with some success. However, they admit that their April update is also a higher skill.
Saying that, Tropical Storm Risk is their name and here is their forecast for Hurricane Season 2020:
The highlighted area is the focus and the accepted “normal” season these days is 12 tropical storms, six becoming hurricanes and three of those becoming Category 3, 4 or 5. So, the above is just a bit above the normal with 15 storms, seven becoming hurricanes and four becoming major.
Why just a little above normal? Because the climate factors are coming in a little above normal for now. El Niño is very weak, and a weak El Niño is forecast to continue through the prime months of August and September. Trade Winds, which when strong, will inhibit tropical storms, are expected to be just a bit stronger than normal (which also puts Saharan Dust over the Atlantic and this also inhibits development). On the other hand, Atlantic sea surface temperatures have been running a little higher than average.
How does Tropical Storm Risk match up with other forecasts? They compare themselves to only two others, Colorado State and NOAA, and while their early forecasts don’t do well, their April update is as good as anyone else:
You can read the entire hurricane forecast report here.
I’ll keep an eye on the forecasts and update you as they come in. But as we all say, it only takes one.