No tropical development is expected over the next few days, but there is some chance that a tropical wave coming west across the Atlantic will make an attempt heading through next week.
Happening now: All noise, no substance for now
Looking out over the Atlantic’s main development region (MDR) this morning, there is definitely some thunderstorm action but there is nothing near organization.
No organization to anything right now in the Atlantic, but thunderstorm activity continues. (Weathernerds.org)
I’m not sure that I would assign a zero percent chance to this developing, but over the next 2 to 4 days or so, there is surely nothing imminent from the slop out there. Either way, look for storms to gradually work west or west-northwest across the Atlantic basin.
The medium range (days 6 to 10): Same story, same places
As we watch the Atlantic’s MDR over the next several days with these emergent waves, I don’t think the medium range will offer a whole heck of a lot different: Keep watching the MDR. There are no signs right now of anything close to home, and the north Atlantic looks quiet at this point. So we’ll keep watching between the Cabo Verde Islands and the Caribbean. If anything were to really get going from this stuff, it would probably wait until it got closer to the islands or the Americas.
Let’s briefly talk about what is expected out around day 7 or so. If we look at the forecast upper level map from the European ensemble mean (an average of about 50 different European model runs), we can see two areas of high pressure. One is over Texas and Mexico; another is over the Atlantic, southeast of Bermuda.
With a tropical wave near the Lesser Antilles on day 7, it should progress west into the Caribbean or islands, bringing additional rain chances to that region. It will probably still struggle to develop. (Tropical Tidbits)
What this setup should do is take the tropical wave, assuming it doesn’t develop, and steer it west toward the Caribbean islands. So I would anticipate some better rain chances in that region by midweek next week. Beyond that, the pattern should allow for the wave to continue west toward the Gulf, unlikely to develop still by late in the period.
Fantasyland (beyond day 10): Nothing coherent, but stay tuned
If you believe the GFS operational model, the wave discussed above will develop at some point in the Gulf. I’m skeptical that will happen, surely as shown by the GFS, but given this is 10 days or more out there’s enough reason to keep watching the progress of this wave.
Overall, there is certainly more persistent “noise” in the extended forecast right now, but beyond monitoring that one wave, there is little else specific for us to really latch onto. So the moral of the story at this point is to just keep watching. We’ll almost certainly have something to talk about before the end of the month.
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.
Overall, British forecasters anticipate about twice as much tropical activity as normal. (Met Office)
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).
Is the end nigh for this little guy? (National Hurricane Center)
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.
There are a couple things down the road to monitor, but in the near-term Invest 96L is beginning to run short on time, as generally dry air and wind shear hinder it from organizing.
Happening now: Invest 96L struggling
One of the things that has stood out to me personally this hurricane season so far (and granted, it’s still early) is that modeling has been very hellbent on at least 3 or 4 systems developing that have never gotten past the invest or depression stage. It indicates to me that there is some sort of disconnect between what makes meteorological sense (what the models would depict) and reality. It’s clear that there has been some sort of inhibiting factor that is limiting storm development this season. So far.
Invest 96L is another feather in that cap, as it is struggling this morning, despite odds as high as 80 percent for development yesterday.
Invest 96L looks no better organized today than it did yesterday, as it continues to lift northward. Development chances are roughly 50/50 now. (Weathernerds.org)
Those odds are down to 50 percent this morning, and quite frankly, we’re going to run out of time. 96L has been dealing with a lot of wind shear of late, and that surely is not helping matters. It seems to also be embedded within a residual Saharan air layer pocket, which means it’s also struggling with some dust and drier air.
Some residual Saharan dust indicating dry air may be helping to inhibit 96L, as tropical systems cannot thrive in dry air masses. (Tropical Tidbits)
Whatever the case, if 96L develops or not, its future is pretty clear that it will turn out to sea and run out of time to develop by about Thursday or Friday. It will not impact land.
Elsewhere, the next few days look quiet.
The medium range (days 6 to 10): A wave to watch, maybe
If we squint, maybe the tropical wave emerging off Africa today and tomorrow has a chance to do something. This will plod west over the next several days, unlikely to develop, initially. If we look at the day 9 forecast for the upper air pattern over the Atlantic, a sprawling area of high pressure is expected to focus near and just south of Bermuda.
Any tropical wave that tries to develop in the Atlantic heading into next week should be directed around the southern periphery of high pressure near Bermuda and toward the Caribbean initially. (Tropical Tidbits)
This will likely force any tropical wave to initially go south and west toward the Caribbean. Thereafter, there are many questions. You can see another high over Texas on this European ensemble forecast above. Options would include the wave staying in the Caribbean if either high pressure can check in stronger or something “splitting the gap” between the two high pressure centers as explicitly shown above. Or something else. It’s early. So we’ll keep an eye on things and see if this becomes actually something to watch or just another tropical wave that fails to find a home in the Atlantic.
Fantasyland (beyond day 10): GFS going wild
Yesterday, the 12z GFS model brought a healthy storm into the Southeast U.S. after developing it from some sort of shenanigans off the Southeast coast. Interestingly, it repeated that overnight and brought a storm into the Gulf. That won’t happen as shown, but I am wondering if some of this is just the models failing to “resolve” the tropical wave shown above. Any ensemble support for development in Fantasyland seems to be connected to that wave. So the activity showing up here may be linked to what we see in the medium range. Either way, it appears things may get at least a little more active here, though how much so remains to be seen. Admittedly, I am a bit more intrigued by <waves hands> all this than I have been by much this season. We’ll keep watch.
A pair of tropical systems have a chance to develop in the Atlantic, but both will scoot out to sea and not be a direct impact land.
Happening now: Invests 96L and 97L
As expected, the tropical wave in the middle of the Atlantic Ocean is on its way to potentially developing later today or tomorrow. This wave is now tagged Invest 96L. Meanwhile, off the North Carolina coast, we have Invest 97L, which is a vigorous area of thunderstorms with a lesser chance of developing in the next day or so.
Two areas to watch; neither is a threat to land. (NOAA/NHC)
Regardless of development, both systems will move out to sea, and neither is a threat to land. Even Bermuda should see only fringe effects at worst.
Why are we confident that both systems will turn out to sea? A quick look at the upper levels of the atmosphere shows that both systems have a pretty easy exit path away from land.
With high pressure west of the Azores, the clockwise flow around it should pull 96L north, then northeast and out to sea. 97L is already embedded in pretty fast flow off to the ENE, so it will rocket out to sea.
Invest 96L
The area we’ve been watching since last week out over the open Atlantic took on the Invest 96L tag over the weekend, meaning it became an area to investigate and we got some additional model data on it to look at. This really just confirmed what we already had confidence in, that this system was likely heading out to sea.
Puerto Rico and the Lesser Antilles are at the bottom left of this satellite image, while Invest 96L is on the right side. It’s heading out to sea, while some scattered clusters of thunderstorms impact the islands. (Weathernerds.org)
On satellite this morning, 96L doesn’t exactly look exciting, though I’ve seen worse looking storms upgraded, so we’ll see what the NHC finds in the next day or two. The 80% probability from the NHC seems perfectly fine here, because there’s a good chance it will develop, but it’s definitely not a guarantee. The ceiling on this system looks like lower-end tropical storm so not a huge deal. It will struggle due to wind shear and sinking air. It has about 3 or 4 days before it’s outta here.
Invest 97L
Admittedly, it’s 97L that looks most interesting this morning.
Invest 97L is hauling out to sea, with no risk to land. (Weathernerds.org)
There’s a hint of spin to it as it moves northeast, but this is more like a nor’easter than a tropical system in terms of how it’s developing (the formation process is being driven more by fronts and atmospheric dynamics than warm waters and heat). While that’s primarily a technicality, it’s all moot as this is heading out to sea. This could graze Bermuda with some thunderstorms as its trailing cool front approaches and stalls near the island. Aside from that? Not much to this.
The medium range (days 6 to 10): Pressing reset
A period of calm is expected to take control of most of the Atlantic basin this weekend and early next week, and we do not expect any storm activity as the atmosphere sort of presses the “reset” button. For the most part, this calm is expected to last into…
Fantasyland (beyond day 10): Still calm? Perhaps.
We don’t see anything of note right now on any modeling that indicates things will pick up at the end of the 10 to 14 day period. Last week, we were hinting at a potential ramp in activity for mid-August. Some of the support for a more conducive background state seems to have faded some, as the Pacific side heats up. There would be two primary ways to generate activity should that be the case, since an active Pacific generally means a quieter Atlantic. First, you’d have to watch close in for something, say, in the Gulf or just off the coast. Second, with a good bit of storminess ongoing in Africa, that could potentially get something to flare up in the far eastern Atlantic in time. But we have plenty of time to watch.
Early August and everything after
Which brings me to what I wanted to touch on more today. Where do storms usually form in the first third of August?
Historical storm origin points in early August. (NOAA/NHC)
The Gulf is a hotspot in early August, with numerous storms historically forming there. We also tend to see flare ups near the Lesser Antilles, as well as a peppering of storm origins across the Atlantic. So where do you look in early August? The Gulf, the Leeward & Windward Islands, and across the Atlantic.
We are entering the ramp up of hurricane season. Accumulated cyclone energy (ACE) for the season to date is quite high, thanks mostly to Hurricane Don. We’re over 16 units of ACE right now for 2023, which is almost twice as much as normal for the end of July. Remember, ACE is a stat that factors in the wind speed of tropical systems and for how long they maintain that intensity, and we sum it over the season (hence: accumulated). Far from perfect, but it gives you a sense of where the season compares to prior seasons in terms of activity.
Accumulated cyclone energy through the end of July will be right around 16 units, which is a good bit above our normal of 9.6 on this date. (Colorado State University)
But, it’s important to note that we still have about 92 percent of hurricane season from an ACE standpoint still in front of us. It remains early. That said, by the end of August, we jump from today’s 8 percent of the season climatologically complete to 30 percent. We ramp things up in a big way after the first third of August. So, the fact that it’s looking fairly calm to start August is great news, but we’ve got a long way to go. Fingers crossed!
