00:00Well, it was about a week ago that we were tracking Arthur, the first tropical storm of the season.
00:06It actually had more impacts as a tropical rainstorm as it pushed across Alabama and Georgia with heavy rain in
00:14Louisiana and also severe weather.
00:17A week from now, we're going to have to keep an eye out for homegrown development near the state of
00:23Florida.
00:24This is the area that we're going to watch as we head into next week here.
00:30Right in here near the Florida coast.
00:32Now, talking with forecasting here, we have a small chance.
00:36I would probably extend this area.
00:38Let me turn on the right pen.
00:40I would probably extend this like this in here for the possibility of what we call homegrown development, tropical development.
00:52Now, it's only a small chance.
00:53I'll show you why we are concerned about that coming up.
00:57But from a historical perspective, when you look at the breeding grounds for June, this is where you would be
01:05looking for development anyway.
01:07It's usually in three areas, the Caribbean, the Gulf, and also the Southwest Atlantic.
01:14We do not look for development in the tropical Atlantic this time of the year, and there's a reason for
01:21that.
01:21Let me show you why.
01:22When you look out in the tropical Atlantic, I'll show you the modeling here.
01:27This is the amount of dry air in the middle part of the atmosphere here.
01:31You could see as we get into next week, look at all of this dry air.
01:35Anywhere you see the yellow or brown, this is dry air or Saharan dust.
01:42And primarily, it covers almost all of the tropical Atlantic.
01:47This is typical for this time of the year.
01:49This is the Saharan dust.
01:51The other product to look at, we could look at precipital water.
01:54And if you would imagine the entire length of the atmosphere, the entire atmosphere, how much water do you have?
02:00Or if the atmosphere was a rag, and you squeezed it, how much water came out?
02:05That's precipital water.
02:07Look how dry it is.
02:09You have these totals in here.
02:10Once you get down in here, right, this blue, this is where you have a lot of dry air.
02:16Now, you will notice, where do you have moisture?
02:20And this is as we get into next week.
02:22You see, here's all your dry air in here across the tropical Atlantic.
02:26So all these waves coming eastward, run into the dry air, and they can't do anything.
02:31But you do have moisture in here.
02:32Look at the red.
02:33Right in here.
02:34This is a frontal boundary or some energy that's going to kind of get pushed near Florida next week.
02:41This is how we get development this time of the year.
02:45It's called homegrown development.
02:48And how it works is this.
02:51Whenever you get a dip in the jet stream coming south, that dip in the jet stream, what does it
02:57do?
02:58It brings frontal boundaries.
03:01It could also produce a gyre down in Central America.
03:05But it's the interaction between the jet stream and these three bodies of water that produces tropical development.
03:13Because if you think about it this way, in order to get tropical development, you need something to spark showers
03:20and thunderstorms.
03:21Because the tropical waves coming off Africa can't survive.
03:24So you need this process to start the area of showers and thunderstorms.
03:28And then if the thunderstorms can sit over the warm waters and develop, minimum of 48 hours, you can get
03:36an area of low pressure.
03:37And that's how you get developed.
03:39So that's the process that we see this time of the year.
03:42Now the question is, is there a process like that?
03:46And the answer is yes.
03:47And it all deals with the upper high.
03:51That's going to build.
03:52Let me explain here.
03:53Let me show you the modeling here as we get in the next week.
03:57Let's do a little two-shot here.
04:00Okay.
04:00So anytime you see a big upper high, look at this upper high by Tuesday into Wednesday.
04:06You see this across the Midwest?
04:08Of course, we're dealing with this.
04:10This is where you're going to get the heat wave.
04:12But I was taught this years ago.
04:15Always look underneath the belly of the upper high for tropical development.
04:20The reason for that is you get easterly winds.
04:22And that can help spin an area of low pressure.
04:25But you see what's going on here?
04:26I was talking about that jet stream coming south.
04:29You've got a little split in the jet stream here.
04:31You see that?
04:32Look at this little tail of energy right in here.
04:36Right in there.
04:37You see that?
04:37Where?
04:38Underneath the belly of the high.
04:40Now this is the European model.
04:42Let me show you the other modeling.
04:44This is the American model.
04:47Look at that area of red across Florida.
04:50That's the European model.
04:51This is the Canadian model.
04:54Still has energy, although not as strong.
04:56Off the south near Florida.
04:59And then you also have the UK Met.
05:01They all show the same thing.
05:03That underneath the belly of the high, you're getting a little splitting of the trough.
05:08That is, energy gets stuck in here.
05:10All right?
05:10And it sits there and it moves east over very warm water.
05:16Now the question is, do you have moisture there?
05:19And remember I showed you this earlier.
05:22Look at this, the precipital water in this area Tuesday and Wednesday.
05:25Look at all this red in here.
05:27So you've got a tremendous amount of moisture.
05:30You have some energy, right?
05:33And you also have very warm water.
05:37Now, do you have any wind shear?
05:39Do you have light winds in the upper part of the atmosphere in this area that would allow for development?
05:45And the question is, you do.
05:47Now, this is the wind shear here.
05:52Now, the system, if it forms, would be moving this way.
05:57You see these wind arrows?
05:58They're showing you that the wind flow here is from east to west.
06:02So it's moving with the energy that's going to be moving from east to west.
06:07So that's not as detrimental.
06:08Now, if we were looking at energy moving from west to east and the wind shear is that way, that
06:15would really weaken it.
06:18But there's not much wind shear.
06:19And let me show you another.
06:20You know, you look in here Tuesday and Wednesday.
06:22There's not much.
06:24Light winds in here, right?
06:27So you've got to keep an eye on this area in the Gulf as we head into next week.
06:32So it's a low chance.
06:34But nonetheless, it's a chance, nonetheless, where you've got to worry about some development.
06:40Again, I would worry that this has to extend into the northeast Gulf.
06:44So let's keep an eye on this Tuesday and Wednesday next week for a homegrown tropical development.
06:50Let's do it.
06:50Let's open it.
06:50Let's do it.
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