TS Kate forms but will have little overall impact

Visible satellite picture showing TS Kate in the central Bahamas

Visible satellite picture showing TS Kate in the central Bahamas

The 2015 hurricane season now has its 11th named storm, Kate. The NHC made the upgrade this morning citing 40 mph winds with a pressure of 1008 mb. Kate is moving towards the northwest but will eventually turn out in to the open Atlantic head of an approaching trough.

Right now, the storm is impacting portions of the Bahamas where tropical storm warnings are in effect. However, much of the inclement weather associated with the storm is located to the east of the low level center, leaving much of the Bahamas free of any significant impacts.

Water temps along the track can still support a hurricane but the upper level winds should prevent that from happening. The official NHC forecast calls for some additional strengthening and Kate could reach 50 mph before being absorbed by a larger storm system emerging from the East Coast later this week.

There might be a period of increased swell activity for parts of the Southeast and East coasts which could lead to additional beach erosion issues during times of high tide as the week wears on. Outside of that, I see no reason to worry about Kate along the United States coast.

I’ll post a video discussion covering the latest on Kate this afternoon.

M. Sudduth 8:50 AM ET Nov 9

One more storm before season ends?

Latest tropical weather outlook map indicating a couple of areas to watch over the coming days

Latest tropical weather outlook map indicating a couple of areas to watch over the coming days

November is typically a quiet month in the tropics and in fact, it is extremely rare for there to be a November hurricane threat to the United States. Cooler near-shore sea surface temperatures combined with increasingly stronger upper level winds usually keeps a lid on things – but not always.

During the last few weeks of the hurricane season, we look to the Caribbean Sea and southwest Atlantic for the best chances of development. Right on cue, both areas have something to monitor over the next few days.

The first area of interest is a broad area of low pressure tucked in to the northwest Caribbean off the coast of Belize. While it looks fairly impressive on satellite imagery, the forecast calls for it to move inland over the Yucatan soon and then over the southwest Gulf of Mexico by this weekend. Although water temps are warm enough in the region, strong upper level winds ahead of an approaching cold front, combined with land interaction, should limit development. Heavy rain and periods of gusty winds are possible as the tropical low moves across the Yucatan over the next day or two.

Recent satellite photo showing two distinct areas of clouds, showers and thunderstorms in the Caribbean Sea

Recent satellite photo showing two distinct areas of clouds, showers and thunderstorms in the Caribbean Sea

Meanwhile, another tropical wave has flared up as it enters the eastern Caribbean Sea. This is the second area that the NHC mentions on their latest outlook. It has a slightly better chance of development over the next few days and this is shown by most of the reliable global computer models. It is possible that this system could eventually become a tropical storm over the southwest Atlantic sometime next week. So far, with the exception of heavy rain and gusty winds spreading in to the Lesser Antilles, there does not appear to be any significant threat to land from this feature. It will be something to monitor but as I mentioned earlier, hurricane threats this late in the season are few and far between.

The eastern Pacific has returned to being very quiet for the time being. After super-hurricane Patricia, this is definitely great news. Water temps are still very warm off of Mexico and Central America and even though the season usually slows down in this region during November, it would not surprise me in the least if we saw one more storm or hurricane develop somewhere in the extreme southeast Pacific before all is said and done. For now, nothing is brewing but the pattern suggests that perhaps that will change in the longer term.

I’ll have more tomorrow.

M. Sudduth 8:30 AM ET Nov 5


Hurricane Patricia a record setting event

It’s been quite a year for tropical cyclones globally. After several years in a row with few intense hurricanes and typhoons, 2015 has seen a remarkable turnaround. The latest is Patricia, now poised to strike Mexico near Manzanillo later today, and it is about as intense as they come.

There is not much I can say in terms of preparedness actions. Simply put, people in the path of this hurricane need to leave, period. If they haven’t done so already, they need to get moving. That being said, there’s actually some good news.

Patricia is NOT a 100 mile wide or 60 mile wide EF-5 tornado. I’ve seen people saying this on social media and it’s just wrong. Let me explain…

A hurricane like Patricia is very rare, obviously. One thing we do know because of the recon flights that have provided incredible in-situ data is that the radius of maximum winds (RMW) is very narrow. In fact, the ENTIRE extent of hurricane force winds, 74 mph to 200 mph in this case, is ONLY 30 miles from the eye. This is extremely important because it limits the amount of real estate that will have to deal with those winds. In other words, if you live just 40 miles from the eye, you would hardly notice as the core passed by. Move 20 miles closer to the eye and it’s a terrifying siege of flying debris and flesh-stripping wind. So while it will be awful for those who have to endure the core, it’s not like we’re talking about 100 miles of coastline laid to waste.

Another aspect of the small RMW is the storm surge. Katrina had a storm surge of 28+ feet in some locations due to its enormous RMW – more than 90 miles at one point. The result was a surge of water pushed onshore from Louisiana to Florida. In the case of Patricia, it will be a small area, maybe 10 to 20 miles, that receives a possible catastrophic storm surge. Wind drives the surge and the wind is only 200 mph very close to the eye.

I bring this up because it is important to keep the facts straight and not let the historic moment become clouded with information that is simply incorrect. Patricia is bad enough on its own and for those who remain in its path, today will be one not soon forgotten.

Texas to receive Patricia remnants

What happens after Patricia makes landfall? First, it will weaken extremely fast over the higher terrain of interior Mexico. Sadly, there will be potential for loss of life due to the flash flooding and mudslides as the torrents of rain impact those same mountains.

Info-graphic concerning the threat to parts of Texas from the remnants of hurricane Patricia

Info-graphic concerning the threat to parts of Texas from the remnants of hurricane Patricia

Interestingly, it looks as though the low level center will be stripped away but the mid and upper level energy will remain fairly intact. This means that there is a slim chance that once the remnants reach the warm Gulf of Mexico, some regeneration could take place. While this is NOT being forecast by the NHC right now, it would not surprise me to see it happen over the weekend or on Monday. What is more likely to happen is that Patricia’s energy leads to more of a non-tropical low pressure area to develop and bring gale force winds and extremely heavy rains to a large part of Texas. All of this will combine with a frontal boundary draped across the region and will help to focus the moisture feed, dumping excessive rain over a large swath of Texas.

In addition to the rain, coastal flooding is a real possibility with the strong onshore flow that is forecast to develop. Water levels could rise several feet in typical flood-prone areas away from the Galveston Seawall. In short, Patricia will leave a mark, even if only indirectly, long after its historic landfall in Mexico.

I will have a video discussion posted this afternoon that will highlight the landfall of Patricia and what to expect after tonight for Texas and vicinity.

M. Sudduth 9:40 AM ET Oct 23

New storm developing in southeast Pacific, Atlantic remains quiet

A new tropical storm is likely developing in the southeast Pacific not too far off the Mexican coastline. The National Hurricane Center will almost certainly begin advisories on the system later today (right now it is designated at invest area 97-E). The development of this soon-to-be-storm is important for a couple of reasons.

First and foremost, it will have a direct impact on the weather across portions of Pacific Mexico over the next few days. Heavy rain with the usual threat of mudslides and flash flooding will an issue due to the fairly close proximity to the coast.

Model plots for 97-E in the southeast Pacific

Model plots for 97-E in the southeast Pacific

Computer models indicate that a track to the west with a gradual bend back to the northwest and eventually northeast is probable over the coming days. This means that there is the threat of a hurricane making landfall in Mexico as the system is forecast to intensify significantly over the very warm waters of the southeast Pacific. Interests along the coast of Mexico should pay close attention to this developing storm. It would not surprise me at all to see a hurricane watch posted for a portion of the Mexican coastline by sometime tomorrow.

The other interesting aspect of this system is where it developed. Right now it is situated just south of the Gulf of Tehuantepec which is itself not far from the Bay of Campeche in the extreme southern Gulf of Mexico. If you remember your geography, the strip of land that separates the two bodies of water is called an isthmus. The developing storm is on the Pacific side of the isthmus and likely precluded any development from taking place in the southern Gulf of Mexico. It is rare to have two tropical cyclones going at the same time so close together – and as such, the Pacific disturbance took over and is now on its way to becoming yet another hurricane for the region.

However, something very interesting may happen down the road. Tropical cyclones are incredible heat engines, driving their convective bursts with warm water. The transport of this energy in to the subtropics can often times lead to larger storms that have part hurricane, part mid-latitude cyclone characteristics. There is a chance that we see that happen with the Pacific system after it makes landfall in Mexico.

WPC precip forecast over the next 5 to 7 days indicating a lot of rain possible for parts of Texas and New Mexico

WPC precip forecast over the next 5 to 7 days indicating a lot of rain possible for parts of Texas and New Mexico

Some of the global models are indicating that at least some of the remnant energy will survive the trek across Mexico and combine with an upper level low coming out of the Southwest to produce a potentially heavy rain event for Texas and New Mexico. While the rain is needed, we could be faced with another instance of too much, too soon. The latest forecast from the WPC (Weather Prediction Center, formally known as the Hydrometeorological Prediction Center) suggests that a wide swath of Texas and part of eastern New Mexico could receive several inches of rain beginning later in the week. The timing of when and where is tough to call this far out but your local NWS office will have the best info concerning local impacts from this rain event.

Remember back in April and in to May, parts of Texas were inundated by very heavy rain as wave after wave of energy moved across the region dumping incredible amounts of water, resulting in widespread flooding issues. While this storm will not be nearly as prolonged, there is potential for more flooding so please pay close attention as the week wears on.

As I mentioned in the headline, the Atlantic Basin remains very quiet right now. I do not see any solid evidence of development happening anytime soon. It appears that a slow moving MJO pulse will eventually make its way in to the region as we get in to early November and it’s possible that we could see more activity flare up at that point, probably in the western Caribbean Sea. We’ll deal with that when and if the time comes.

I’ll have more in the developing storm in the southeast Pacific on my video discussion later today.

M. Sudduth 8:45 AM ET Oct 20

Quiet time short-lived? Some model support for Gulf development

Substantial MJO pulse forecast by the ECMWF over the next two weeks

Substantial MJO pulse forecast by the ECMWF over the next two weeks

The rest of this week is likely to remain nice and quiet across the Atlantic, Caribbean and Gulf but once we get to next week, things could change. Here’s why…

First of all, the time of year supports Gulf of Mexico or western Caribbean development. We shift away from the Cape Verde region and the waters between there and the Lesser Antilles towards a pattern that favors development much closer to land areas. We might be seeing that come to fruition in the coming days.

The other reason I think development could happen is the progression of a strong MJO or Madden-Julian Oscillation pulse. Think of it as a period of fertility in the tropics. Instead of dry, sinking air, the MJO typically brings with it an increase in convection and a general rising motion in the atmosphere. These things are needed to even have a chance for a tropical storm or hurricane to develop.

According to the GFS and the ECWMF, the MJO is about to amplify significantly in to the phases that would, in theory, support development either in the southeast Pacific or the western Caribbean/Gulf of Mexico regions.  Water temps are plenty warm and so now it’s just a matter of watching to see what happens. So far, both the GFS and the ECMWF show signs of developing a tropical storm in the 8 to 10 day time frame. For what it’s worth, the two models are in remarkable agreement on the timing and the general placement of such development – the southern Gulf of Mexico. I usually don’t pay much attention to model forecasts beyond the 5 to 7 day time frame but when the two (rival) models are in agreement, it is worth watching a little closer.

Right now, nothing to worry about at all. It’s important to remember that we are still very much in hurricane season and it’s not over until it’s over. There are signs beginning to come in to focus that we might have one more system to deal with before all is said and done. Obviously I will keep a close eye on how things shake out over the next week or so.

I’ll have more here on this tomorrow.

M. Sudduth 8:35 AM ET Oct 14