00:00Tropical Storm Mocha has officially formed, and this is going to be a complicating matter
00:06for those in southwestern parts of, and really any part of the Big Island of Hawaii.
00:11The Big Island recovering from last weekend's hit, Lala dealt a really punishing blow to
00:17the island there as more than 100 homes were destroyed or swept away in extreme floodwaters
00:23and mudslides were a big problem.
00:24Well, it's official that Mocha has now joined us, being named at 11 a.m. Hawaiian Standard
00:31Time, or for those of you tuning in from the eastern U.S., 5 p.m. Eastern Time.
00:37So here we have the Pacific, and here we got Hurricane Lala, and now Tropical Storm Mocha.
00:42They're beginning to spin its wheels over portions of the area around the water southeast of Hawaii.
00:50So we need to keep a close eye on this storm, and it will be one that brings us some
00:56impacts.
00:57It'll be an impact that brings some heavy rain and a modest amount of wind to the area of
01:04the Big Island of Hawaii this weekend.
01:06So let's take a look at the future of this storm here, and I'm going to show you the overall
01:12model guidance that we're growing more and more confident it's going to stay to the south
01:16of the Big Island.
01:18Last weekend, Lala, the center of Lala passed within 30 miles of the Big Island.
01:22This is going to be probably 100-plus miles south of the Big Island.
01:25But it's a geographically larger storm, actually.
01:28Lala's still out there, by the way.
01:30Then we're also watching other areas of likely development here in the eastern Pacific.
01:35That's going to be kind of a hotbed of activity in the days to come.
01:39Let's look at some model guidance here.
01:40And that's going to give us a sense.
01:43We're going to begin in the Pacific, and then we will visit the Atlantic briefly here.
01:46I want to save a little time for the Atlantic.
01:48So let's look at this here.
01:50This is in its formative stages.
01:52It's taken its good old time.
01:53It was a tropical depression for, I think, 30 hours.
01:5730 hours from 11 a.m. Thursday Eastern time to 5 p.m. Friday Eastern time.
02:04It took 30 hours to graduate through tropical depression stage.
02:07But here we are.
02:08And you'll notice that some steering influences involve high pressure to the north.
02:14And there's also a trough, a couple of troughs, actually.
02:16You're going to kind of reconfigure the steering flow into the Pacific as well.
02:22So we've got an area of low pressure up here, a low pressure up here.
02:24And then we have our Hurricane Lala.
02:27There's Lala, by the way.
02:29And in between, we've got the Hawaiian Islands.
02:31So again, big concerns about the Big Island.
02:34It won't be a direct hit, though.
02:36We're growing more and more confident of that.
02:37You can see that a trough that passes well to the north is going to kind of put a big
02:44dent in that ridge of high pressure.
02:46And it will send a little bit of wind shear southward.
02:51And you can see what looks like almost fracturing of mocha into two systems.
02:56I don't think it's going to fully do that.
02:57But you can actually see this bit of debris and a little extra lift and vorticity in the
03:03atmosphere to the north.
03:04But the primary track of surface low pressure, here we're looking aloft, about 20,000 feet
03:09up.
03:09But the primary low is going to stay to the south.
03:11And that's going to be the remnant of the storm that passes south.
03:15And I shouldn't say remnant.
03:16It will still be a named storm as it passes to the south of Hawaii.
03:19But it's not going to strengthen and ramp up to a hurricane like Lala did.
03:23We're more and more confident that it will be probably a lower end system.
03:27By the way, there's another hurricane that forms then and moves from east to west but
03:31is at a northern latitude later next week.
03:34And that will probably be eroded away by some cooler water before it would reach Hawaii.
03:38But we need to keep an eye on that.
03:39So here is the GFS.
03:41Well, I showed you the GFS.
03:42Here's the European.
03:43European shows some of that kind of fracturing due to some wind shear where you see a little
03:47bit of vorticity, but the primary storm stays to the south.
03:52The primary storm stays to the south with a near miss just south of the Big Island of
03:55Hawaii.
03:56Let's look at the surface here.
03:57This is the surface pressure field down near the surface of the ocean.
04:01And the GFS comfortably to the south, comfortably to the south.
04:06And some of that fracturing we were seeing with the structure of the storm aloft, that
04:10would be tied to some of those showers north.
04:12But the primary low stays way to the south with MOCA passing way south of the Big Island.
04:17But it will bring some rain.
04:19The European is a little farther north.
04:21Still comfortably south.
04:22We're not concerned about landfall with this one, like we were with Lala when that was a
04:26debatable issue.
04:27But it's a big enough storm that on the north side of this circulation, there's going to
04:31be a strong upslope flow that dumps heavy rain still into the Big Island.
04:35Let's look at rainfall.
04:36Here's the GFS.
04:37And the GFS, even though it's way to the south through the whole course of the storm, it produces
04:42two, three inches of rain on the east side of the island.
04:45Let's look at the European.
04:46This is a different tale though, a different story.
04:48This one really lights up.
04:50It's a little closer.
04:51It's a larger storm geographically, even though it's not as strong as Lala.
04:55Lala was like a dense buzz saw.
04:57This would be a larger, slightly less intense, but larger storm.
05:01And the moisture field will still send a lot of moisture right up the slopes of the volcano
05:06in the mountains here, even up into areas farther north.
05:10So we're going to be dealing with, you get into the blues six to eight inches of rain in
05:15some spots.
05:16That's a concern.
05:19And just to head back briefly to some of these other disturbances that we tracked.
05:23Again, we're going to see some development soon in other parts of the East Pacific.
05:29And that's the disturbance that may make a run to near Hawaii.
05:31We've got another one out there that may stay a little farther northeast.
05:35And then yet another one behind that following into the end of the month.
05:39All right.
05:39Let's go to the Atlantic here.
05:41And here we're tracking three separate disturbances.
05:44One traditional tropical wave, another tropical wave that will not organize, another one that
05:48won't organize, another one that won't organize.
05:50And then we have an area of deep convection southeast of Bermuda.
05:53And then we have a storm that's really not tropical, but it's a good pinwheel, sending
05:57some needed rain to Europe soon.
06:00That one, low chance of development, this is how we're playing it.
06:03We've got three lemons out there, but the one that has our attention the most is going
06:07to be this tropical wave that may organize.
06:09Now in the short term, we do have some roadblocks out there in the Atlantic.
06:15In the Atlantic, at least when we get far enough west, when we get far to the west, you can
06:20see we've got a lot of wind shear out there.
06:23And that's going to be a factor in keeping most of the trouble, at least into the end
06:29of August, most of the trouble will stay away from the Caribbean because of wind shear and
06:35dry, dusty air.
06:35But we do need to keep an eye out for this tropical wave, which may have a future as we
06:42track it in the days to come, moving into parts of the west central Atlantic.
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