Eric Berger

One-sentence summary

There is one area in the Central Atlantic that we’re tracking, but we don’t expect it to develop; otherwise things are blissfully quiet for early August.

Approaching “go” time for the Atlantic season

The start of August means that we’re now just a couple of weeks from when activity in the Atlantic Ocean often starts to pick up. The outlook this season is complicated because of several factors. One is that sea surface temperatures in the Atlantic basin are absolutely sizzling. During the last month the “main development region,” a stretch of tropical water between Africa and the Caribbean Sea where most major Atlantic hurricanes develop, the sea surface temperature averaged 82.4° Fahrenheit, a full degree above any previous July. This trend will certainly continue into the heart of hurricane season, and is very concerning.

At the same time, with El Niño active in the Pacific Ocean, we’re seeing somewhat higher wind shear and sinking air over the Atlantic Ocean. So far, this has helped to dampen activity in the deep tropics. But we’re about to get to the point in the season where the African wave train rumbles to life, and it’s not clear to me that there will be enough shear to overpower the formation of some very strong and threatening hurricanes. To that end, the United Kingdom’s Met Office released an updated seasonal forecast that calls for a very busy season with 19 named storms and, worryingly, 6 major hurricanes. Overall, based on the Accumulated Cyclone Energy index, the British forecasters anticipate about twice as much activity as normal.

Seasonal forecasts are just a guide, of course. But we’re going to need to keep a close eye on the tropics for the next 10 to 12 weeks.

Happening now: A disorganized wave

The only system of note in the Atlantic tropics right now is a tropical wave several hundred miles east of Bermuda. It’s struggling at the moment, but has a slight chance of becoming a tropical depression or storm over the next week. As its contending against dust and shear, I’d guess the end is near. But we’ll see. Regardless, it’s not a threat to land anywhere so we can pretty much ignore it. (Well, that is, we could ignore it if we weren’t a website dedicated to covering tropical activity in the Atlantic basin).

The medium range (days 6 to 10): Off the coast of Africa

As Matt noted on Tuesday, a tropical wave moving off the coast of Africa at present could be something to watch in a week or so as it slowly plods across the Atlantic Ocean. If this becomes a tropical depression, due to steering currents in the Atlantic, it probably would move toward the Caribbean Sea. Still, this is no sure thing, and probably not something we should be too concerned about at the moment.

Fantasyland (beyond day 10): All quiet on the Western front?

In the overnight runs we’re not seeing the global models get too excited about anything in the next two weeks. That doesn’t mean nothing will happen, it’s just that right now there is nothing obvious out there that will become a problem. The tropics are unpredictable like that.

One-sentence summary

There are a couple of areas that we’re watching, but overall things are fairly quiet for July with no imminent threats to land; however we’re now just six days away from August and at some point the switch is going to flip.

Happening now: Not too much, thankfully

We’re watching a (very) poorly defined area of thunderstorms near the Bahamas that Matt mentioned yesterday. However the odds are still stacked against this becoming something to worry about. So I want to talk a little bit more about climatology today.

We’re still about three weeks away from when we typically would expect the Atlantic tropics to come alive. This often happens around mid-August, when sea surface temperatures near their summer peak, wind shear reaches a nadir across much of the Atlantic, Caribbean and Gulf of Mexico areas we’re concerned about, and tropical lows move off the Africa coast with some regularity. This period is easily visible when we look at historical activity in the Atlantic, typically running from August 10 to around October 20.

The past offers no guarantee for what will happen in the year 2023, of course. Already sea surface temperatures are absolutely sizzling in the Atlantic and Gulf of Mexico, and are plenty warm to support the development and strengthening of tropical systems. We are also (see next item below) starting to see tropical waves moving off the coast of Africa with a bit more frequency.

What’s been holding us back so far this year has been El Niño, and its tendency to keep wind shear levels in the Atlantic above normal. We’re going to really need that pattern to hold on this summer, or else the Atlantic basin is likely going to explode with activity in about two or three weeks.

The medium range (days 6 to 10): A new contender emerges

As expected, the National Hurricane Center has started to track a tropical wave that recently moved off of Africa into the Atlantic Ocean. The global models are somewhat bullish on this system as it moves westward across the Atlantic Ocean, and it may develop into a tropical storm in five to seven days, or so.

The most likely scenario for this system, however, is that it curves to the north before threatening the Caribbean Sea or continental United States, but we’ll continue watching it all the same.

Fantasyland (beyond day 10): Happily quiet

There’s not much else out there, even in the fevered minds of the global models 10 days or later from now. That will change, so for now we’re embracing the quietude.

One-sentence summary

As Tropical Storm Don swirls in the Atlantic, we’re watching another system that likely will not develop due to dry air.

Happening now: Don

Tropical Storm Don looks a little better this morning in its satellite appearance, and has a window to strengthen somewhat over the next day or two. During this time it probably will top out as a reasonably strong tropical storm, but northing more. Fortunately Don continues to follow a track that will keep it far out to sea.

By this weekend Don should lift far enough north that water temperatures will become too cold to sustain tropical storm characteristics. Once Don reaches waters below 70 degrees Fahrenheit this weekend, it is safe to say that Don will knotts be long for this world.

The medium range (days 6 to 10): Atlantic waves march west but have a lot of dry air to fight off

The National Hurricane Center continues to call attention to a tropical wave in the eastern Atlantic, forecasting a 20 percent chance of development over the next 5 to 7 days as it comes west. If I were buying stock in storms, I would give this one a “sell” rating due to a number of factors, including dry air to the system’s north and, eventually, probably in the Caribbean as well. Matt mentioned yesterday that the Saharan dust inhibiting this system is on its way toward the Gulf of Mexico eventually, so look for some reddish sunsets later next week along the U.S. Gulf Coast.

As for this tropical system, there may be a brief window in about five days, before it reaches the Caribbean Sea, for a depression of tropical storm to develop. Therefore areas such as the Lesser Antilles should probably watch this system. But it’s not the kind of thing we need be too concerned about. Certainly, there will be bigger fish to dry the deeper we get into the season, in a few weeks’ time.

Fantasyland (beyond day 10): Biding our time

Overall, aside from Don, and potential shenanigans from the system mentioned above, things look fairly quiet for the rest of July.

But for those who know the Atlantic hurricane season, that’s to be expected. The real action often does not begin until the first or second week of August. At that point we’re going to have to see whether wind shear from El Niño is able to counteract historically warm sea surface temperatures in the tropical Atlantic. If not, well, we’re going to be busy here at The Eyewall.