TC/EQ Update Tue 22 June

The US NHC has stopped advisories on Claudette as it no longer has a closed circulation (one of the requirements to be a tropical cyclone). The remains will continue to the northeast just off the coast of Nova Scotia and Vinland (Newfoundland) today, producing gusty winds and rain but shouldn’t be dangerous with some common sense. Elsewhere, it’s tropical wave season, and NHC is tracking one approaching the Caribbean but it only has a low (30%) chance of development over the next five days. There is a better chance for a system off the west coast of Mexico (70%). In the West Pacific Tropical Depression Six is expected to strengthen into a Typhoon and pass well east of Japan.

NHC/TPC Tropical Analysis, Tuesday Morning 22 June. Click to embiggen …

There was a fairly strong and shallow earthquake just of the coast of Asia Minor, near the Greek islands of Tilos and Nisyros, 70km northwest of Rhodes. No reports of damage yet but I would expect there to be some minor damage.

Claudette, Dolores Updates

Tropical Storm Claudette is a Tropical Storm again, strengthening as it exits the North Carolina coast this morning with gusty winds and rain. It caused only scattered damage across the Southeast, but sadly a number of fatalities in road accidents, and two caused by a falling tree. Here is the damage swath (past and forecast) based on the Monday morning forecast:

Although the official forecast track ends at 36 hours, the storm will bring gusty conditions to the Canadian Maritime Provinces mid-week as an extratropical storm.

I haven’t mentioned Dolores in the last couple of days, since I was selfishly concerned with being on the fringes of Claudette, but that storm made landfall in Mexico bringing some flash flooding, power outages, and mudslides to western Mexico inland from Puerto Vallarta. Elsewhere, there is a weak storm in the West Pacific, the long range (and unreliable) models have some stuff, but that’s it for the moment.

Tropical Depression Claudette (Sunday Update)

Claudette is now moving into North Goergia, on its way to the Carolinas and offshore. Here’s the 7am radar and GFS model overlay to give you an idea of the structure of the storm …

Radar and GFS winds at about 5000 feet

The latest forecast shows it hanging together and starting to strengthen later today before it moves offshore. That’s not terribly unusual for this kind of storm, since it can draw on warm moist air from both the Gulf of Mexico and Atlantic (look at the wind barbs in the above map). Here’s the impact swath using my TAOS/TC model driven by the official forecast:

Swath o’ doom. Click to embiggen any graphic

For the Georgia/SC Coast, that blob of rain currently over North Florida will be moving up our way in the wake of Claudette, and the forecast is for rain chances to increase and conditions deteriorate during the day. Winds are already picking up, and should be at their worst in the early afternoon (4-5pm), with rain chances and rates highest between 7pm and midnight. There is a flash flood watch up for Savannah, Hilton Head, and Beaufort (but not south of Fort Stewart at the moment). As for tornadoes (thanks Savannah Morning news for the fear-mongering scare piece on the front page today), expect a tornado watch later today as there is enough rotation and low level shear from Claudette and its interactions with the surrounding systems to spawn tornadoes, but the biggest potential threat is from gusty winds in rain bands breaking tree limbs, etc. In short, a blustery, rainy Pentecost Sunday (in the Orthodox Churches), so keep your weather radio close just in case.

#Claudette makes landfall

The system formerly known as Potential Tropical Cyclone Three got organized and tropical enough just before landfall (which happened this morning around 2am) for the National Hurricane Center to name it. Here’s the radar composite as of 6am ET:

MRMS Composite Reflectivity, 602am ET, sat 19 June 2021. Click to embiggen

The biggest story for the next few days is rain. Here is the HPC seven day forecast, which includes the impact of a strong front expected to arrive in the region Tuesday …

HPC Seven Day Rain Forecast (19-26 June 2021)

As you can see, a foot of rain is forecast for parts of coastal Alabama and Mississippi, and upwards of 6″ into central Georgia. This will cause some scattered flooding, so beware.

Here is the forecast for Claudette. Some pretty big changes since yesterday in the long term – rather than dissipating over the southeast, the circulation is expected to survive and reach the Atlantic and regenerate before following Bill’s track to Vinland (Newfoundland) and Nova Scotia. May get a bit blustery up there, but by then the extratropical transition should be well underway so the worst should stay offshore.

TAOS/TC simulation based on official NHC forecast as of 5am Saturday.

For Coastal Georgia/SC, this will mostly be a rain event, with some gusty winds right on the ocean as we will be on the fringes Sunday and Sunday Night. Heavy rain is possible, and the local Charleston Weather Service office mentions the potential for a tornado, but the risk is small. Still worth keeping your weather radio close by … will be watching tomorrow.

Potential Tropical Cyclone #Three

The National Hurricane Center has started advisories on Potential Tropical Cyclone Three (AL032021). It’s a very large system, and while it may get more organized as it approaches the northern Gulf of Mexico, this isn’t really a traditional hurricane threat. There may be tropical storm force conditions right on the coast, but the big worry here is a lot of rain from Louisiana up through the southern Appalachian Mountains. Here’s the impact swath based on the first advisory at 5pm ET Thursday …

Click to embiggen …

There are tropical storm warnings up for the Louisiana, Mississippi, and Alabama coasts, although the storm isn’t really close to tropical storm strength according to the latest data and may well not reach that threshold. It may be blustery right on the coast with some waves and minor coast flooding – and this will be well east of the center, maybe even as far as the big bend area of Florida as shown in the above simulation – but again the story here is likely to be a lot of rain in an already wet and nearly saturated area.

Watching the #GulfofMexico

As of Wed. morning, the US National Hurricane Center has a disturbance in the Gulf tagged with a high chance of becoming a tropical depression or greater in the next five days – 90% as of the 8am ET update – then moving north into the Texas coast, spreading heavy rain across Texas, Louisiana, and Mississippi. Most of the models have not been as enthusiastic; the GFS lowtracker consistently kills the circulation off in the next 12 hours, before it drifts north back into the Gulf. Here’s the latest (06z) GFS simulation tracks:

The Navy GEM model (which ordinarily isn’t the most reliable of the global runs) is closer to the NHC scenario:

So what to do? This isn’t likely to be a catastrophic event, mostly just a lot of rain. Of course, that could be a problem with river flooding across the region. The New Orleans WFO has a good perspective:

… there should be a few points to remember. 1) until there is a well-defined circulation for the models to initialize (if one develops), guidance is likely to jump around on details, 2) with weak systems, impacts, especially heavy rainfall, can be significantly displaced from the center of circulation, and 3) it doesn`t take a named tropical system to produce heavy to excessive rainfall events in our area.

NWS WFO New Orleans Discussion, 346 AM CDT Wed Jun 16 2021

So we’ll have to wait and see what happens tomorrow, when the northward movement is supposed to start. That puts the major impacts in the US on Saturday. If you live in an area near the Gulf Coast (and 200 miles or so inland) where it floods if you get heavy rain, worth paying attention to.

Tropical Storm #Bill, #Gulf of Mexico, Earthquakes in the #Philippines

It suddenly got busy from a storm and earthquake hazard standpoint, although so far not anything catastrophic. Starting with Tropical Storm Bill (AL022021), like his namesake, the world famous lead tongue for Billy and the Boingers, he is too fast to live and too gross to die. Bill is only marginally a tropical storm – the winds are above the threshold, and it has convection (thunderstorms) but the structure is really a hybrid. It is currently forecast to make landfall in Vinland (Newfoundland) while dissipating, impacts should be minimal, just a blustery and rainy day … click any graphic to embiggen:

Elsewhere in the Atlantic and East Pacific, Tropical Depression Carlos is a fish storm in the open ocean and should dissipate without incident. There is an invest area (AL94) off the coast of Africa that shouldn’t amount to much. But there is an area to watch in the Gulf of Mexico. It is presently over a somewhat favorable area as it meanders over the southern Gulf. While previously forecast to move inland over central america, it is now expected to migrate north. It has some opportunity to become a tropical depression before reaching the northern Gulf Coast (Louisiana/Mississippi area). But more than likely this is just going to be a rain event no matter where it ends up. Here is an overview with the NEDSIS formation potential analysis in greens and yellows:

In the geophysics realm, there has been a while series of earthquakes on Mindanao, Philippines. No reports of significant damage or injuries at the moment, but these were shallow enough and strong enough to produce damage, and I expect reports will filter in over the next couple of days …

The deep dark area just to the right of the Philippines is the Philippine trench, part of the “Ring of Fire” that encircles the Pacific Plate. It is a subduction zone that has produced some devastating events in the island.

Tropical Depression Two

Since I was traveling yesterday/today, naturally the National Hurricane Center found some clouds and spun it up it in a tracked storm 😛 So we now have Tropical Depression Two (AL022021), which may briefly be elevated to Tropical Storm strength (and thus bestowed with the name Bill). Here’s the TAOS/TC impact swath based on the 5pm ET advisory … TD2/Bill should stay offshore, with minimal impacts to the US and Nova Scotia, although as it merges with a non-tropical low off the coast of Canada it may bring blustery conditions to Vinland (known to the locals for obscure reasons as Newfoundland).

Elsewhere, the thing in the Gulf (AL92) is now forecast to drift more northerly, and has a 70% chance by NHC of spinning up. More on that tomorrow …

Tropical Storm #Carlos, fear mongering the invest in Gulf (Sunday Update)

Two “live” storms today and one invest area of interest in the Gulf of Mexico. The first real storm is Tropical Depression Koguma, a tropical storm that crossed Hainan island a couple of days ago and has made landfall in Vietnam. It is dissipating rapidly, mostly a heavy rain event, no major damage reported or expected. In the East Pacific, yesterday’s Tropical Depression is now Tropical Storm Carlos. It is expected to remain just over tropical storm strength the next few days before encountering dry air and cold water. Carlos is now a very small storm – notice how compact the wind field became as it spun up. It is way offshore and no threat to land … click to embiggen:

The Invest (potential storm investigation area) in the southern Gulf of Mexico is expected to meander in the Bay of Campeche for the next few days. NHC gives it a 50% chance of become a tropical storm, which may be generous. Essentially all of the dynamical model guidance keeps it headed south or west into the Mexican coast as a rain event, and no threat to the US. Of course, that’s not stopping headlines like in USA Today, “First threat of 2021 Atlantic hurricane season? Forecasters eye developing tropical system in Gulf of Mexico.” with breathless bullet points like “The system could impact the Gulf Coast by the end of next week.” and “It would be the first storm of the season to affect the U.S.” Here is the actual NHC discussion:

A large area of cloudiness and showers over the Bay of Campeche and adjacent land areas is associated with a trough of low pressure. Slow development is possible over the next several days while the broad disturbance moves little, and a tropical depression could form in this area by Thursday or Friday. Regardless of development, heavy rainfall will be possible over portions of Central America and southern Mexico during the next several days. Please consult products from your local meteorological service for more information.

Formation chance through 48 hours…low…10 percent.
Formation chance through 5 days…medium…50 percent.

From NHC Tropical Weather Outlook, 2AM ET, Sunday 13 June 2021

Maybe I’m missing something, but the US isn’t even mentioned … As usual, your best bet for avoiding the fear-mongering when it comes to hurricane guidance in the US and Caribbean are the official NHC reports. As noted before, if you live in a hurricane prone area have a plan (and keep in mind rain flooding can extend hundreds of miles inland so check your flood insurance).

Tropics Update – 12 June 2021

We have one weak system to look at, WP05, which is presently a depression over Hainan Island and forecast to become a weak tropical storm before making landfall in Vietnam. The biggest threat is rain and mudslides in the mountains.

Elsewhere, there are two “invest” areas (systems that have formation potential, and are organized enough for the models to start tracking) being watched in the eastern Pacific. Here is GFS based forecast tracks. along with the conditions for development over the next 48 hours …

a

NHC gives each of these a 40 percent chances of becoming storms. Another area that will be getting some attention is that faint blue blob in the southern Gulf of Mexico. It’s not organized enough to be an invest area, but NHC is watching it as has some potential for something to form next week. They have it tagged in their five day forecast as having a 30% potential for development. You’ll also note a band of blue off of the US East coast – conditions are somewhat favorable, but nothing organized on the horizon.

In short, stormy weather for Vietnam, may a weak storm hitting southern Mexico in two days with mostly rain, and the usual angst inducing conditions in that bathtub known as the Gulf of Mexico. Got your hurricane plans ready? Still time to think about that in the US …