Tropical Depression Florence, Typhoon Mangkhut, and Helene, Isaac, and Joyce: September 16, Update A

Hello post peak-week of Hurricane Season! And lo and behold, they all went poof and vanished... 

Tropical Depression Florence:  Well she behaved pretty much as expected as she approached land (and after that) - a cat 1 at landfall near Wrightsville Beach, about 10 miles south of Wilmington NC. She brought some wind (90mph at landfall - cat 1 range: 74-95mph) and a lot of buckets of water with her. I'm sure you've all seen the news - around 800,000 without power (as expected - there are a lot of trees in that area) and a lot of flooding and post-storm evacuations because of the water. She is still bringing a lot of rain and flooding - along rivers - so be careful if you are in a flood-zone! Here's the latest satellite imagery, still showing a lot of rain in the system - a bit over S. Carolina, and a lot over N. Carolina:

Unfortunately 17 people have died from Florence and so, I strongly suspect that this name will be retired from the list of storm names in the future. By the way, storm names are on a six-year cycle, and any that cause great destruction and bring a large number of deaths are retired... for example, we'll never see another Hurricane Harvey (been replaced by Harold), Irma (replaced by Idalia), or Maria (replaced by Margot). Florence is now a Tropical Depression and this will be my last post on this one. 

Typhoon Mangkhut: Meanwhile, over in the western Pacific, Super Typhoon Mangkhut made landfall on Luzon island in the Philippines as a cat 5 storm with winds in excess of 160mph (cat 5 range: >156mph). The death toll from this (so far) in the Philippines is 64, possibly higher. But many consider this lucky - the expectation was for more, especially as this system was a cat 5 and had, at one point (before landfall), winds as high as 180mph. After the Philippines, this system went on as a mid-sized cat 2 Typhoon to visit southern China - Hong Kong with winds of 100mph (cat 2 range: 96-110mph), where a 3 meter (10 ft) storm surge was reported. It is now overland and is currently a cat 1 storm with winds of 81mph (cat 1 range: 74-95mph). That's it from me on Mangkhut. 

The other storms: If you recall way back to 2 days ago, we still had Helene, Isaac, and Joyce.

Helene has exited stage right, and is heading towards the UK for a cup of tea and some jaffa cakes. She'll bring some wet and windy weather... but you may not notice as it's autumn and that'll get those leaves off the trees. This is my last update on Helene (unless something odd happens over there like there's no more tea or something...). 

Isaac is that small blip (yellow cross on the map) in the Caribbean. He has some circulation in the lower half of the troposphere, and is going to be bringing a bunch of rain to Jamaica:

For now, this is my last update on Isaac unless he gets a bit wild - I'll keep an eye on him. 

Joyce is still lurking as a Tropical Depression. She has some circulation and a little bit of convection, but she's just doing circles in the Atlantic and isn't bothering anyone (unless you are on a boat out there), so this will be my last update on Joyce. 

The next name in the Atlantic will be (Captain) Kirk. I'll be back if he beams down. :-) 

Ciao for now!

J.

Twitter: jyovianstorm

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DISCLAIMER:
These remarks are just what I think/see regarding tropical storms. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast. This is not an official forecast.
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Hurricane Florence: September 13, Update B

Good job I posted a bunch earlier - the internet in this particular airport is a little dicey! 

The news is getting better for the Great Florence Watch of '18. She looks a little weaker as she is starting to interact with land - that and the wind shear, and possibly that she's been dragging this out sooo long that she's beginning to cool some of the water underneath her is working. She is now solidly a cat 2 storm with winds of 105mph (cat 2 range: 96-110mph), central pressure of 955mb. Even that might be a little high and she may be a weak cat 2.  There's also what looks like a delicious patch of dry air in her outer bands, which is clearly seen in the infrared satellite imagery (and slightly seen in the visible imagery) and her eye is flickering:

Although she won't be as big a wind issue as a major (cat 3 or higher) hurricane, she'll still bring down some trees/branches and damage some roofs. She's definitely a hurricane because she still has good vorticity throughout the troposphere, but the key thing to watch out for now is when her center actually crosses the Gulf Stream in a few hours - that's where the water is warm and it's deep and warm so if she's going to grow or intensify again, that's when it will happen. But I have to say that I am jolly pleased with that patch of dryer air! That's fantabulicious! 

She's centered at 33.4N, 75.5W, heading NW at 10mph - she has slowed down over the last few hours as predicted by the NHC and as shown in their track forecast. She may slow down enough that she'll actually cool the water underneath her even more after she's had her fill, which would be just fine. But added to that, the waters closest to the coast are cooler, so that will also help to keep her a little in control.

Although she is getting weaker, there will still be water issues - rain and of course the storm surge as she is a big storm and is slowing down offshore which means she'll continue to push water.  The highest surge will be to the north of her because that's the direction the winds are pushing water on-shore. For example, Wrightsville Beach, NC, is showing around 1.3 ft above normal. 

Some more bits of advice: 

- Watch out for downed power lines - don't go splashing in the puddles after she passes by. 

- When the power goes out, don't forget to start by rescuing the ice cream first.

- And my friend says be safe when the power does go out... she can't afford too many baby showers in the spring.

More from me from some other point in space and time.

Be good! 

J. 

Twitter: jyovianstorm

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DISCLAIMER:
These remarks are just what I think/see regarding tropical storms. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast. This is not an official forecast.
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Hurricanes Florence and Helene, Tropical Storms Isaac and Joyce, the Gulf of Mexico Blob, and Super Typhoon Mangkhut special: September 13, Update A

Which star constellation does this Constellation of Storms remind you of?

Hurricane Florence: She's currently at 32.5N, 74.3N, heading NW at 17mph. The track is towards the Wilmington area: 

I've heard from a few - some have evacuated, some are staying put. Definitely get out if you are in a flood zone! If you are hunkering down you may be without power for days (or weeks), so be prepared for that. 

The outer rainbands have already reached the coast. The good news is that she steadily decreased in intensity from a cat 4 yesterday and is now officially a cat 2 because of that wind shear:

Winds are officially 110mph, which really makes her a borderline cat 2/cat 3 storm (cat 2 range: 96-110mph), and central pressure is 956mb. The even better news is that the wind shear now looks like it will stay put all the way to the coast, so she may weaken further. I do see that the eye is struggling to maintain itself - if it does go away, then we definitely have a cat 1 storm. So that would be jolly good as far as the wind impacts go. 

But there is still the issue of the water, and in particular, the Gulf Stream...she has to cross this deep warm current. The faster she moves, the less time she'll spend over it. If she does slow down over it, she'll have a LOT of rain. If she takes that curve and moves along the coast just off shore, she'll also have a LOT of rain. We saw this when Tropical Storm Fay (not a strong storm) stalled just over the Florida Current (which is the Gulf Stream off the east coast of Florida) some years ago and dumped a lot of rain over the Melbourne area, causing major flooring issues (if I recall correctly... I could go and read my blog from then, but I'll only find out how boring I am now that I've grown up compared to then, so why bother? :-)). The storm doesn't have to be big or windy to bring a lot of water with it. 

A couple of data resources for you (assuming you have power and time!) to monitor Florence:

1. Storm Surge: to look up the storm surge for yourself in the area closest to you, read the <Technical Alert!&gt in this post which discusses NOAA's unfortunate replacement of their storm surge site tidesandcurrents (https://tidesandcurrents.noaa.gov/), which doesn't load very well for me and is still difficult to use. Currently it looks like the highest is around 0.5ft above normal. 

2. SECOORA resources: SECOORA stands for the South-East Coastal Ocean Observing System Regional Association. This is a collection of off-shore and coastal measurements and models made by a bunch of people (e.g. universities, government entities etc.) - this includes things like winds, water temperature, currents, waves and a whole host of other useful information. (by the way, SECOORA is one of 11 such Ocean Regional Associations around the country). There is a lot of information on this page that they have kindly put together to focus on Hurricane Florence: https://secoora.org/eyes-on-hurricane-florence-data-resources/. This includes live-feed cameras (it's nighttime now, so these aren't too interesting at the moment) and other goodies.

Right now for example, the winds at an buoy 27 miles offshore from Wrightsville Beach, NC (run by UNCW) is showing that the winds close to the sea-surface have started to pick up and are just under 27 knots, which is around 31 mph (screenshot):

Hurricane Helene: She has weakend further and will continue to do so. She's currently a mid-sized cat 1 storm with winds of 80mph, central pressure is estimated to be 983mb. She's at 22.4N, 36.9W, heading N at 13mph. The dry air and wind shear continues to be her enemy and she's looking rather worse for wear because of it: 

She's going to continue heading generally northwards, towards the Azores, but will continue to weaken:

Tropical Storm Isaac: Isaac is barely a Tropical Storm now with winds of 45mph, central pressure of 1006mb (TS range: 39-73mph). He's at 15.3N, 58.5W heading W at a very rapid 20mph. He'll be crossing the islands today and be in the Caribbean by this evening: 

He'll be a lovely breeze, bringing with him a nice cooling drizzle: 

If you are on one of those islands, you may not even notice anything much amiss. I don't think he'll even disrupt your umbrella drinking activities. 

SubTropical Storm Joyce: I wasn't even going to bother, except that on the day Joyce is planning to join her big sister, Helene, in the Azores and will arrive about a day or so later...

 Luckily she's a dinky little thing with winds of 45mph. 

Gulf of Mexico Blob: Yes, for those of you who are still awake after all of the above, there is a blob in the southern Gulf of Mexico. There is a very weak circulation signal in the lowest level of the troposphere: 

And an equally weak signal in the mid-troposphere, which is not in the same location because of wind shear. There is some disjointed convection and the NHC give this one a 60% chance of development. 

Stay tuned. Next name is Captain Kirk... 

Super Typhoon Mangkhut: A quick update as this is a big one... it will make landfall in the Philippines at around the same time as Florence in the US. She's now strong cat 4 storm with winds of 150mph (cat 4 range: 131-156mph) and is a very very robust and good looking system:

Ok, that's it for today (a travel day). More tomorrow (also a travel day) when I can. 

Be good out there... don't do anything daft!  

Until tomorrow, 

J. 

Twitter: jyovianstorm

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DISCLAIMER:
These remarks are just what I think/see regarding tropical storms. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast. This is not an official forecast.
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Hurricanes Florence and Helene, Tropical Storms Isaac and Olivia: September 12, Update A

Welcome to mid-September - on average, statistically the busiest part of the Hurricane Season:

(Credit: NOAA)

In reverse order... 

Tropical Storm Olivia: She's at 20.9N, 154.2W, heading W at 15mph. She's a relatively weak TS now with winds of 50mph, central pressure of 1005mb. She'll hit Hawaii today, but will really be a little breezy with a few drops of rain here and there. This is my last post on Olivia.

Tropical Storm Isaac: He's a little weaker than yesterday with winds of 65mph, central pressure 999mb. He's currently at 14.5N, 53.0W, heading W at 16mph and should be crossing the Lesser Antilles in the Caribbean on Thursday. The dry air took it's toll and he still isn't through it all:

He still has some convection, as we can see from the infrared satellite imagery: 

He has almost no circulation (vorticity) in the upper troposphere, but it's pretty good in the lower half, so he's definitely a Tropical Storm. He is moving over warmer water now, which will keep that convection going, but I agree with the forecast that he'll remain a TS as he gets to the islands: 

Hurricane Helene: She's still a cat 2 storm with winds of 100mph (cat 2 range: 96-110mph), central pressure of 973mb. She's at 18N, 35.4W and has taken a northward turn and is heading NW at 10mph:

She still has a very strong circulation (vorticity) in the upper troposphere, which is a sure sign she's a hurricane:

She's also been battling dry Saharan Air, and is not over as warm water as Isaac, and she's under some wind shear so her convection is a bit wishy-washy (technical term ;-)): 

But despite that, you can still see her eye which is an indication of just how strong and robust she was. A weaker storm would have crumbled by now. 

Hurricane Florence: And that brings us to our little Florence, the storm that's had one-to-many turns on the Magic Roundabout! She's currently a mid-size cat 4 with winds of 140mph (cat 4 range: 131-156mph), central pressure 946mb:

The eye is strong with this one, and we know she has good vorticity throughout the troposphere, so her structure is good, as is the convection surrounding the eye (that red indicates high cloud tops, which means strong thundery activity): 

The marginally good news is that she is experiencing some wind shear, which is why that convection is a little lopsided - it looks like that will carry on for at least a day, so she should be weakening a tad in that time (to perhaps a cat 3). 

She's currently at 28.5N, 69.5W, heading WNW at 17mph:

Although the track is showing landfall near the Wilmington, NC area at the moment, there is a lot of strong convection to the north as well, so pretty much everyone in that area should expect many buckets of rain. If you are umming and ahhing over whether or not to evacuate, a good rule of thumb is to run from the water, hide from the wind. If you decide to evacuate, don't forget your children, pets, and of course, the wine...

Reminders: listen to your local emergency managers. And if she is a major storm at landfall in your area, you may not be able to get back to your home for a few days (or weeks). 

Finally, over on the other side of the world, Super Typhoon Mangkhut, currently a cat 5 storm, with winds of 157mph (cat 5 range: higher than 156mph) is heading to the Philippines... landfall in about three days.  

 

More tomorrow!
J. 

Twitter: jyovianstorm

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DISCLAIMER:
These remarks are just what I think/see regarding tropical storms. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast. This is not an official forecast.
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Hurricanes Florence and Helene, Tropical Storms Isaac and Olivia: September 11, Update A

Jumping right in... (with an additional quite note on Hawaii... again)

Hurricane Florence

She certainly did intensify yesterday, just as the NHC said she would and faster than I expected she would. This is both great and also not great - one may say its very agathakalogical in fact! ;-)  

The bad side is obvious - she's now a 4 storm, and a very good looking one at that. Currently her wind speeds are holding at 140mph, which makes her a mid-level cat 4 (cat 4 range: 130-156mph). Central pressure was last measured to be 944mb. She's had a very solid eye, which is one obvious indication that she's a major storm:

(Ain't she boo-ti-ful?)  

Her structure is also really solid - great circulation (vorticity) in the lower half of the troposphere, and that line of vorticity we saw a day or so ago in the upper troposphere has changed so her upper level vorticity can be seen and is quite strong now too. 

So why is it great that she became a major storm as predicted? Yesterday was one of the few times since I started this, about 13 years ago, where the NHC intensity forecast surpassed mine so perfectly. As you may remember, about 3-4 years ago, their one-day track forecast overtook mine and now I defer to them on that. For intensity, they haven't been doing so well - not even a few days ago, earlier in the lifetime of Florence - so whatever happened over the last two days (the data and models they used) was a good move. Bravo! Now if they can replicate that for ALL storms ALL the time, then I can retire from this blog (and just post jokes and sci-fi geekiness instead :-)). :-) 

She is currently at 29.5N, 62.4W, heading WNW at a decent 13mph. Her track is also honing in on the mid-US east coast:

The troubling part is that there really isn't much to inhibit her from staying a strong storm. There isn't any wind shear, the water is warm - and on top of the warm water where she is, she still has to cross the Gulf Stream to get to the US east coast, which means that she'll have a nice deep-warm water supply. She's also clear of most of the dry dust (Saharan Air Layer): 

There's a small patch closer to the coast, but U think it's too far north to make much of an impact. So we are looking at a big beast as far as I can tell.

The other troubling thing is that she may slow down and stall as she gets closer to the coast because of a high pressure that they are forecasting to build up over the US. NOAA (which includes both the NHC and the NWS) are gathering extra data over land in order to get the most input for the models and monitor this situation more closely. 

So, if you are in the Outer Banks of NC, definitely get out now. If you are in another area that is subject to flooding and in the cone tomorrow (which not only includes the coast, but also river banks and places with poor drainage when it rains - even inland a bit), I would get ready to leave (or leave if it will take a couple of days). If you are in a place which is normally dry, then get ready to hunker down. Remember: Run from the Water, Hide from the Wind. Above all, pay attention to your emergency managers because they have the most up-to-date local information. 

Tropical Storm Isaac

Just a quick note that he's been downgraded from being a cat 1 yesterday. Winds are now 70mph, central pressure is 997mb. The dry air is the major factor in keeping him in check, and it looks like it extends all the way into the Caribbean. He is currently at 14.5N, 46.9W, heading W at a good 16mph:

He will be moving over warmer water as he approaches the Caribbean, so that will give him some energy, but the competing dry air should keep him relatively in check - perhaps a strong TS or cat 1. 

Hurricane Helene

She 'rapidly' jumped from a TS to a cat 2 storm yesterday - I think she was a hurricane a couple of days ago, so I'm not surprised at the official upgrade. She's now officially a borderline cat 2/cat 3 storm, with winds of 110mph (cat 2 range: 96-110mph), central pressure 968mb. I think she's a solid cat 3 - and therefore also a Major storm already. She also has a consistently solid eye, which we can see in the overall Atlantic satellite imagery: 

And her structure throughout the troposphere is as strong, if not stronger than Florence's structure. 

She's also combatting some dry and dusty air as she follows Isaac, but despite that, she is a big storm in size - which you can also see from the Saharan Air Layer image above. I think they have underestimated her intensity.

She is currently at 15.5N, 32.4W, heading WNW at 12mph. Fortunately, her track forecast keeps her out in the Atlantic at the moment:

Tropical Storm Olivia

And just briefly, for those of you with an interest in Hawaii, they are under yet another storm watch with TS Olivia currently at 21.9N, 149.7W, heading W at 10mph: 

Winds are 70mph, central pressure is 991mb, so she's a very strong Tropical Storm:

She has a fair amount of convection in her though, so get those raincoats out and throw the deck chairs into the swimming pool so they aren't flying around. Stay safe! 

Back tomorrow!

J.

Twitter: jyovianstorm

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DISCLAIMER:
These remarks are just what I think/see regarding tropical storms. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast. This is not an official forecast.
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Hurricane Florence and Tropical Storms Isaac and Helene: September 9, Update A

Travel Day - 2 of 3 in a row. Here's the overall Atlantic view for today. First, the visible satellite imagery: 

And the infrared (cloud top temperatures) imagery, which shows the level of convection (rain and thunderstorms and whatnots (technical term ;-)) and really gives us an indication of how severe the storms are: 

Hurricane Florence

She's now just barely a cat 1 storm with winds of 75mph, central pressure 984mb (cat 1 range: 74-95mph). Earlier today it looked like she may have been trying to form an eye, but if she was, it isn't very clear:

Her structure isn't very well developed either, with most of the convection currently to the north. And although her structure is good in the lower half of the troposphere, there isn't a good signal in the upper troposphere yet, so I really think she's still a very strong Tropical Storm, but I'll go with the official estimate of barely a cat 1 storm with winds just 2 mph over the limit. They say she'll intensify into a cat 3 storm tomorrow (a major hurricane) - I think they are basing this on the fact that she'll be moving over warmer water tomorrow. That will cause a little intensification, but I don't know if she'll get to a cat 3 - but they may know something else that I don't know. I do see a little bit of wind shear in her path, so that might just result in a slower intensification. Guess we'll see what happens tomorrow on that front. 

 

She is currently at 24.4N, 56.3W, heading W at 6mph. The track is currently heading the the US east coast (as I'm sure you know!):

Getting to the coast in about 5 days. First, as it says on the cover of the Hitch-hikers Guide to the Galaxy, "Don't Panic". Get ready! Second, just a note that 5 days ago, the location and track she's on now was outside the cone:

 

So although you should all be ready, please keep in mind how much that cone can still shift. 

Tropical Storm Isaac

His circulation is good throughout the troposphere now, so he should be a hurricane. They have increased him to a strong TS with winds of 65mph, central pressure 999mb. That dry air is taking its toll though and the convection is quite weak, as you can see in the infrared satellite imagery. 

Tropical Storm Helene

Currently, I think Helene is the strongest of the three, although they have her as a TS with winds of 65mph, central pressure 997mb. Her convection is quite strong (also from the IR satellite imagery), but her structure throughout the troposphere is really good, which means she has some great circulation (vorticity). Here are the maps for 500mb (mid-troposphere) and 200mb (upper troposphere) - you can see the signals of all three storms quite clearly in the first map, but really only well for Isaac and Helene in the second:

Although Florence is under an upper-level low trough (that red line extending across the Atlantic that you can see in the last map above) - so I'm sure that is helping her a little. If that wasn't there, she'd be a weaker storm. 

I'll be back tomorrow. We'll see what mischief Florence has got up to then! Must run... another city, another plane...!

Ciao,

J.

Twitter: jyovianstorm

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DISCLAIMER:
These remarks are just what I think/see regarding tropical storms. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast. This is not an official forecast.
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