00:00We're going to take you to the tropics here to mix it up a little bit because, you know, typically
00:04by the 11th to 12th of August, we'd be doing the tropics quite a bit here with the forecast feed.
00:11We haven't had a whole lot of fodder lately with the Atlantic so quiet because of wind shear.
00:15This has been anticipated, and that goes hand in hand with a strong El Nino, warmer than average water temps
00:22in the Pacific.
00:23We have extra wind shear as the downstream correlation in the Atlantic wind shear tends to keep storms disheveled, lopsided,
00:31and it prevents them from organizing.
00:32We've also had a lot of dry, dusty Saharan air across a big chunk of the Atlantic basin, but things
00:37are beginning to change.
00:38You can only hold back father time for so long, and it is getting into mid-August here.
00:45We're kind of entering a maybe 70-day stretch when we have the most active hurricane activity, maybe a 60
00:52-day stretch.
00:52We're the most active activity in the tropics in a calendar year, typically.
00:57So here we are, and there are several tropical waves out there.
01:00I'm going to go back here. I'm trying to set this into motion, but I'm going to make myself disappear
01:05and highlight a few of these tropical waves with little troughs.
01:09Here's one about to reach the Lesser Antilles, the signature of one moving into the Dominican Republic.
01:16But there's a tropical wave that is unlikely to organize that I just highlighted.
01:20However, there's another one that we have highlighted in red.
01:23This guy has a pretty good chance at organizing another tropical wave moving off of the coast,
01:29and yet another one soon to move off the coast in the days to come.
01:34So a very active tropical wave train.
01:36There's also a zone of low pressure here up way to the north, kind of exiting stage right,
01:41that will be moving under the path of that total solar eclipse that's going to be scooting across the area
01:48here up into Iceland.
01:49So as we keep an eye on things, I'm going to get into models here in a moment,
01:54but I wanted to show you that we are betting on this one tropical wave to organize here late this
02:01week as it moves west.
02:03But you'll notice that our heading is not directly west.
02:06If it were directly west, it would stay down here at this certain latitude to move into the Lesser Antilles.
02:11It's likely to be pooling maybe west-northwest and perhaps could brush the British Virgin Islands
02:18or perhaps the Leeward Islands here, the parts of the Leewards or the northern Lesser Antilles.
02:22But it's just as likely to maybe be up this way, near the northern edge of the envelope of possibilities.
02:28It will be curving eventually.
02:30So we need to keep an eye on this.
02:32And before I get into the models proper, I wanted to kind of highlight what we're looking at here.
02:37You might say, first off, the deep purple.
02:40Strong wind shear.
02:41There is a wall of wind shear on the north side of this storm system and this tropical wave.
02:46It is staying just far enough south to be in this region of favorable winds, less wind shear.
02:52But once it makes it to a certain latitude, we're likely to see this get drawn north
02:58and it will probably be impacted by this ribbon of strong wind shear.
03:02So we're not expecting this to barrel into the east coast of the U.S.
03:05It will probably be a storm that lifts near the Lesser Antilles and is also impacted by some wind shear.
03:12But we're also tracking the dry air out there.
03:16And you might have thought at the beginning of this loop, why didn't we highlight this farther west?
03:20This is one tropical wave that's unlikely to go.
03:23This is the one that we're putting our eggs into that basket.
03:28And there is some dry air.
03:29This is the water vapor loop.
03:30It's kind of the x-ray of the atmosphere.
03:32A lot of dry air coupled with wind shear just to the north of this storm.
03:36So there's a big zone here with lots of inhospitable conditions with a combination of wind shear and dry air.
03:43And that's been the case in the Caribbean and into an area just barely north of the tropical Atlantic.
03:49Let's go into the modeling here.
03:52And here you can see the GFS.
03:53What does this do with this primary tropical wave?
03:56We're looking at spin in the atmosphere of vorticity.
03:59You can clearly identify this feature here.
04:01Thursday, you know, if this verified, this would become a tropical depression around that time, if not sooner.
04:06And you can see it gets a little bit less cohesive in the world of the GFS as it gets
04:11drawn a little north.
04:12In fact, that closed height line is lost, that black line, the black ring around the center of the storm,
04:21because it would probably be disheveled by extra wind shear.
04:24And by the way, there's some dry air up there to the north as well.
04:27So it's a feature that we might only see hold intact for a short period of time.
04:33As it gets driven around the Bermuda Azores High that had been over Bermuda,
04:39now it's reorienting itself over the central, north central Atlantic.
04:43And that'll be a steering influence in allowing this to draw north.
04:47But you can see it doesn't really hold together all that well.
04:51And then it gets lost and it gets kind of just disheveled and ripped apart there over the west central
04:58Atlantic.
04:58Now, the European, what does that do?
05:00The European organizes it into a tropical depression.
05:03It carries it a little farther south.
05:06So here we are Saturday, 8 p.m. Eastern.
05:09GFS, a little farther north.
05:10European, a little farther south.
05:13And it may make a closer pass here to the Leewards.
05:17And then as we move forward in time, it would also become kind of diffuse
05:22and lose some of its organization as the Bermuda Azores High.
05:25The difference, I think, in the steering, the GFS, Bermuda Azores High, is a little farther northeast.
05:32And the European location is a little farther west.
05:35So that would allow it to come a little closer to the islands.
05:37Now, as we take a look at what this might look like with precipitation, let's go forward in time.
05:42Here comes this disturbance, probably a tropical depression.
05:45And then maybe a tropical storm for a brief time.
05:47And then it becomes a wave.
05:48And the GFS would bring a lot of the moisture north.
05:51But it actually does, at the surface, carry center of circulation over some of the islands.
05:57But it would be a very low-end system.
05:59We're looking at 10, 12 millibars.
06:00That's near the global average pressure.
06:02So it's a very feeble low-pressure system relative to nearby air.
06:07And then it continues to move west.
06:08And you can see it just kind of gets eroded away as a decreasingly strong tropical wave
06:14with a big chunk of moisture splitting and being pulled north.
06:17So it kind of gets sheared apart with moisture being drawn north and then other concerns to the south.
06:22So that's something to keep an eye on.
06:23I wanted to briefly take us also into the Pacific because look at this.
06:28An area of organized lift in the atmosphere.
06:32Watch what happens with this one here.
06:34It moves west into Hawaii as a tropical storm or perhaps hurricane.
06:39Saturday night to Sunday.
06:40That's a GFS.
06:41Look at the European.
06:42There's good agreement.
06:43We're going to dig into this story more tomorrow with the forecast feed.
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