00:00Well, it's Memorial Day, and as we step into the unofficial start to summer, we begin to turn our eyes
00:06into the tropics because we do need to at least keep an eye out for some early season tropical development.
00:13Officially, the hurricane season in the East Pacific is underway. No prospects for development yet. But in the Western Atlantic,
00:19it officially starts June 1st. That'll be early next week. And we sometimes do see early season or even preseason
00:26development. We are just keeping
00:29an eye out for a plume of moisture that'll be sliding north. And we want to talk about early season
00:35development, homegrown development, where this often happens, where we often see the interaction between the jet stream, at least the
00:43southern branch of the jet, and some tropical moisture. This is something we don't find in late August or September
00:51because the jet has migrated by then so far to the north that it is just kind of the tropics
00:56are out of reach for it. So instead of watching systems
00:59coming across the Atlantic from the western coast of Africa, as we might in the middle and right when we
01:06had full stride there in late August and September, this is where we often see these June storms form. So
01:13generally, we're looking at areas close to the Atlantic coast, within maybe a thousand miles of the U.S. coastline.
01:19So that puts the Gulf and the western Caribbean, and also the Deer Shore waters of the western Atlantic as
01:27our areas of concern, just in general. And we're talking climatologically, not necessarily about the current pattern. There's one aspect
01:36of this, though, that could become an area to watch, as I'm kind of highlighting an area to the east,
01:41where we will be seeing an increase in moisture in the days to come.
01:45So we're looking at interaction between the jet stream, or at least the southern branch of the jet, and this
01:51is kind of an exaggerated version. There are times when the southern branch of the jet may actually clip the
01:58Yucatan. Other times, it's farther north, and it's a little more muted, but we're trying to prove a point here,
02:03or at least indicate the general concept.
02:06We talk about sometimes an upper-level low-pressure system or even a gyre, a broad zone of circulation over
02:13Central America. Over warm water, low pressure can form, and if you get at least 48 hours of interaction
02:20between the southward position of the subtropical jet, and that to sit over that warm water long enough to help
02:31to create this environment of extra lift, if that happens for 48 hours or longer, then we begin to think
02:37about development.
02:37So again, that's a key thing, and Bernie always does a tremendous job of explaining this, and again, that's a
02:42key part of this whole conversation.
02:44So we will be watching for an opportunity for some development, perhaps. It's not something that we're highlighting as a
02:55high likelihood or anything like that, but there's some interaction between a dip in the jet, and you can see
03:01when we look at the real-world positioning of this dip in the jet stream early June this year.
03:07It's not as far south as our little conceptual example earlier, where that actually kind of touched the Yucatan, but
03:13it's up closer to the Gulf Coast.
03:14But we are going to be seeing this area of a moisture draw, and some of that's going to be
03:20facilitated by kind of a vacuum effect here off the east coast of Florida on the east side of that
03:25subtropical jet.
03:26So we're going to be watching a disturbance drift north through that region, and as we look at this here,
03:31let's take a look at this week.
03:34These bright colors here, by the way, are areas of spin or vorticity in the atmosphere.
03:39I'm going to go out to Thursday, maybe even Friday.
03:42And at this point, you can see a weak disturbance kind of moving through the area north of Honduras, southwest
03:49of the Caymans.
03:50And then also, you can see some closed thickness lines there, a hint of some jet stream energy that will
03:59have migrated far enough south that we're going to see a little bit of extra lift in the atmosphere over
04:05the northern Gulf.
04:06So they're still pretty well separated from one another Friday night, but as we move forward into Saturday, you can
04:11see there's a little bit of a general confluence here,
04:15where this disturbance that then crosses Cuba and the Bahamas gets a little close to this somewhat flat wave within
04:22the subtropical jet, and they begin to get a little closer to one another.
04:26Now, they're probably going to generally miss their connection in terms of maybe this zone of low-pressure loft stalling,
04:35the jet stream dip stalling long enough over this area of disturbed weather coming out of the Caribbean.
04:41But there will be some interaction, and then you can see it likely will be a case where this never
04:47fully organizes, but it gets drawn east and pulled out through the areas around the Bahamas, maybe into the Bermuda
04:53area.
04:54That was the GFS. Let's take a look at the European, pressing pause on maybe Friday.
05:00At this point, the European a little bit, you know, not quite as well defined here with this disturbance coming
05:07out of the Caribbean.
05:08It's a little flabbier looking and maybe a little more ill-focused, but the general idea of a dip in
05:15the subtropical jet, maybe not as pronounced, that 582 thickness line.
05:19It barely climbs onto the map.
05:22Meanwhile, in the GFS, it's farther south over Jacksonville.
05:25So, the 582 thickness line over Savannah or maybe Hilton Head or Beaufort or Charleston in the European.
05:31582 thickness line, or the height line, I should say, down over Jacksonville there in the world of the GFS.
05:39So, the message here is that the European, the dip in the jet stream is not quite as sharp, but
05:44we will be watching some increase in moisture drawn north over Cuba.
05:48This is the precipitable water.
05:50If you were to squeeze out all the moisture in the atmosphere in a vertical column and bring it down,
05:54how much rain would you actually get?
05:56And this is, again, showing us the deep maroons.
06:01Sometimes the color scheme is counterintuitive.
06:03The deep maroons and the purples and pinks, that's actually more moisture up here.
06:08You get into the maroons and don't think of that as dry.
06:11Think of that as wet.
06:12And that plume of moisture comes across Cuba.
06:16It impacts southeast Florida for a bit Sunday, Monday, and then it kind of gets hung up and marinates over
06:21the area around the Bahamas there in the GFS.
06:24In the European, it comes north maybe not as dramatically, and it gets kind of sheared a bit.
06:31So, what we're doing with all this here when it comes to our forecast, we talked about the increase in
06:36showers and storms.
06:36We will see an increase in showers and storms in south Florida.
06:39Very low chance for tropical development down this way.
06:42But I would expect a slight increase in downpours in south Florida and the Bahamas at the end of next
06:47weekend.
06:48That's your forecast feed.
06:49That's my IGP andre's brought in B um tweet on mobile.
06:49I think the That's why I thumbed up.
06:50Look up,
06:50That's why we've been cuttingě´ë 29.
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