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Attention Turns to Jose, Two More Systems Active Over the Open Atlantic

Good Afternoon! 

The tropics have begun to really ramp up yet again, with Jose still meandering north of the southern Bahamas, newly formed Tropical Depression 14, and a vigorous tropical wave that has been designated Invest 96L.

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Tropical storm Jose has been on the upswing over the past 18 hours or so, as the strong wind shear that has been blasting it ever since Irma made landfall has finally abated to some degree. The storm developed very cold convection right over the center last evening, and this likely worked to help reorganize the storms core a bit, since earlier microwave passes showed that the system had become severely tilted to the point that the mid level and low level centers were no longer aligned. At this post is being written, the hurricane hunters are currently investigating the system, and have found winds just around the threshold for a Category 1 hurricane along the southeast portion of the circulation. Typically the strongest winds are found in the northeast quadrant, so I would no be surprised if this mission found winds of around 80 mph, but I will wait for the NHC to make that official decision of reclassifying it as a hurricane. As stated, shear has begun to weaken, and Jose will be over very warm sea surface temperatures of around 29-30C for the next 36 hours, along with relatively moist mid level atmospheric conditions. This should allow the system to strengthen back to a high-end Category 1 Hurricane, or even a low-end Category 2 before shear really begins to increase to high levels in about 48-60 hours.

Current hi-res visible satellite imagery of Tropical Storm Jose over the open Atlantic with 70mph winds.

Current hi-res visible satellite imagery of Tropical Storm Jose over the open Atlantic with 70 mph winds.

The track of Jose is what remains the hot-ticket item. Over the past few days, there has been a noticeable shift westward, with some global models even showing Jose making landfall along the east coast. Once Jose is positioned between Bermuda and North Carolina on Monday, steering currents will begin to break down and the storm should begin to slow a bit while moving to the north. As the storm slows down, the consensus from the reliable models seems to show that more mid level ridging will build over and around Jose to slow it down even more once we get to the Tuesday afternoon period. By this time, a the storm will likely be encountering very strong wind shear and much cooler waters, which should force it to become a large extra-tropical system near the 40/70 ‘benchmark’ by Wednesday. While direct impacts are unlikely from this system outside of some gusty winds and possible rainfall along with coasts, strong wave action and life-threatening rip currents are likely to last well into next week as the storm slowly moves eastward over time. There will also be an enhanced threat for beach erosion, especially if the storm slows down as it nears the area. We will have a special update this weekend if conditions change, and direct impacts from Jose seem to be on the increase.

This afternoons ECMWF model showing Jose south of New England and heading towards the east

This afternoons ECMWF model showing Jose south of New England and heading towards the east

Invest 96L East of the Lesser Antilles 

A strong tropical wave with a healthy amount of spin is currently located about 1000 miles east of the Lesser Antilles, and has become much better organized over the past day and a half. This system was a par of a large eastern Atlantic monsoon trough, which split into two halves, with the right side of the trough organizing into TD14. During the day today, the system has been able to sustain moderate to heavy amounts of convection over its presumed center of circulation. Visible satellite imagery shows that this system may have a weak surface reflection, with banding beginning to show up on the southern periphery of the invest. However, we have not had a reliable scatterometer pass of this system that is able to show whether or not a system has a closed surface circulation. Regardless, the system is currently within a very favorable area of windshear which lies around the 5-10 knot range. Additionally, the system is over warm waters of 28-29C, and remains embedded within a very moist pouch that surrounds the system. The environment looks very favorable for continued development of this system over the next day or so, and I would not be surprised to see the system become a tropical depression or storm as early as Saturday evening.

Invest 96L this afternoon showing the system gradually becoming better organized

Invest 96L this afternoon showing the system gradually becoming better organized

Over the next few days 96L should continue heading west/west northwest towards the Lesser Antilles, possibly reaching the islands as soon as Tuesday. With favorable environmental conditions, it appears likely that the system will at least be a mid-grade tropical storm at that point, with some of the other model guidance showing a hurricane nearing the islands. Due to the fact that we do not even know whether or not the system has a closed circulation, it is very heard to gauge exactly how strong this will be once it nears the islands, but the Islands should very closely monitor the progress of this system over the next five days, especially the island of Antigua, which is currently housing the population of Barbuda, which was completely destroyed by Irma when it was a 185 mph hurricane. The track of this system beyond the islands will be heavily reliant on the future of Jose, so make sure to check back over the next few days when these details become clearer.

This afternoons GFS model showing 96L becoming a strong tropical storm/hurricane just before reaching the Lesser Antilles

This afternoons GFS model showing 96L becoming a strong tropical storm/hurricane just before reaching the Lesser Antilles

Tropical Depression 14-No Threat To Land

TD14 formed over the far eastern Atlantic from a strong tropical wave, and was designated by the NHC yesterday evening. The system seems to be experiencing some moderate amounts of mid level shear this afternoon, which has displaced the heaviest convection from the low level center. Despite this, the system will be over warm waters and within a moist environment over the next 72 hours, and is expected to become a tropical storm over the next few days as it gradually heads WNW. TD 14 is thousands of miles away from land, and most models show the storm eventually dissipating as it encounters very strong shear and dry air from an upper level trough over the central Atlantic. Depending on what 96L does over the next 48 hours, the next two names on the list of Lee and Maria.

We will have a full update on Monday!

Afternoon visible shot of Tropical Depression 14 over the far Eastern Atlantic

Afternoon visible shot of Tropical Depression 14 over the far Eastern Atlantic

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Have a great weekend!

Steve Copertino

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Showers and Thunderstorms Possible, Hurricane Jose Still Meandering Over the Open Atlantic

Good evening! 

Today was a transitional day for much of the area, as the remnants of Hurricane Irma and another mid level system congealed over the Ohio Valley, and worked to produce widespread cloudiness and isolated showers today. While this area of showers is mainly concentrated with the main mid-level system over the Ohio Valley, a warm front will be pushing in from west to east as we talked about last time, but looks to significantly slow once it crosses the Pennsylvania/New Jersey area as it feels the leftover high pressure just off the mid Atlantic coast. This warm front will have some small amounts of lift associated with it still, so showers will be possible for the remainder of the evening, with some showers having locally heavy downpours. The overall threat for heavy rain should be mitigated somewhat by residual subsidence and dry air, but any areas that experience these showers should expect a quick 20-30 minute period of at least steady rain. The combined factors look quite poor for any kind of flooding conditions, except for some very isolated ponding on roadways in the absolute heaviest showers.

Regardless, temperatures were able to get into the upper 70’s to lower 80’s across the area, despite some cloud cover in spots. One thing that was quite noticeable this afternoon and into the early evening hours, was the marked increase in low level humidties over the region. This due partly to the large breadth of leftover tropical air that has since collapsed outwards from the remnants of Irma and has since become entangled with the warm front. As we head into the overnight hours, the threat for showers will gradually diminish with time, and it appears the vast majority of the area should remain dry. Due to the increased low level moisture, it appears that overcast conditions and even some patchy fog will be possible, especially inland. Tonight’s conditions will be quite poor for radiational cooling to take place, so expect temperatures to stay in the low to middle 60’s for lows this evening.

This evenings latest high resolution visible satellite imagery, regional radar mosaic, and surface observations, showing only a few areas of showers lingering over the area (Courtesy of College of DuPage)

This evenings latest high resolution visible satellite imagery, regional radar mosaic, and surface observations, showing only a few areas of showers lingering over the area (Courtesy of College of DuPage)

Thursday Into Saturday

After meandering and festering over the Ohio valley for over two days, the large mid level trough associated with the remnants of Hurricane Irma will finally begin to lumber on east. This mid level system should continue to increase mid level moisture over the area, with PWATS nearing the 1.5 to 1.8″ range.  Depending on how much sunshine the area can get tomorrow, it is possible that the area can destabilize a bit, with 500-1500 joules/kg of SBCAPE possible. With the increased moisture, surface instability, and small amounts of enhanced lift from the mid level system, widespread shower and thunderstorm development may be possible as we head into the early to mid afternoon hours tomorrow. This activity would mainly be focused in a corridor from eastern Pennsylvania, southern New York, and fading into the NYC and Long Island area.  Shear will be quite meager with this decaying mid level system, so no severe thunderstorms are likely tomorrow. We may however see some isolated strong showers and thunderstorms capable of producing gusty winds, heavy rainfall, and very small hail. Additionally, these storms are expected to have a low threat of flash flooding due to their modest forward speed and PWATS being on the lower side of what we would want to see for any kind of flash flooding. Storms should reach their peak for the western areas around mid to late afternoon, with the activity translating to the NYC metro by late afternoon and into the evening. By this time, any stronger storms should have begun to weaken considerably at this point. Highs during the day will be in the upper 70’s to lower 80’s once again, with a muggy feel to the day.

Friday looks to be quite similar as the decaying mid level system pushes the last of its energy over the region. This should allow the slow-moving frontal boundary to move directly over the region during the afternoon hours on Friday, leading to more possible shower and thunderstorm development. Daytime heating and instability should pool up to the point where the meager amounts of lift should be able to trigger showers and an isolated thunderstorm to form over the area during the late afternoon hours, into the early evening. At this time, it appears that the greatest coverage for any showers and thunderstorms will be just to the north of the NYC metro area. Highs should once again reach into the upper 70’s to lower 80’s over much of the area, with lows ranging from the lower to middle 60’s.

By Saturday, a weak area of high pressure is expected to form over the area, providing an opportunity for warmer and drier conditions to take hold. Most of the Northeast should remain mostly sunny with light winds and high clouds during the weekend, possibly lasting into the early portions of next week.

NAM model showing the decaying mid level trough moving over the area, potentially sparking a few round of showers and thunderstorms

NAM model showing the decaying mid level trough moving over the area, potentially sparking a few round of showers and thunderstorms

Hurricane Jose

Jose is still meandering over an area between Bermuda and the southern Bahamas. Jose currently has winds of around 75 mph, just barely making it a hurricane. The system is still experiencing some strong vertical wind shear, separating the mid level center from the low level center, which is inhibiting any kind of strengthening, and should continue to do so until it can find a more favorable environment, if it ever does. Jose has completed a cyclonic loop and should begin to head off to the North starting tomorrow. The vast majority of the models take Jose well out to sea, but there have been some model runs showing an area of high pressure developing over Jose as it tries to escape out to sea. Instead of continuing north, the system slows down and begins to head westward towards the east coast. This is occurring in the Day 6-8 period on the models, so continuity and reliability is very low, and not much stock is being put into these operational runs. Only a minority of the EPS members show Jose making it to the US east coast, and such a scenario is extremely unlikely. Regardless, we will monitor the progress of Jose over the next few days. We will have an update on the system by Friday afternoon!

This evenings latest GOES 16 infrared imagery of Hurricane Jose, showing the storm located north of Puerto Rico with very cold cloud tops and a sheared appearance to the system. Jose should track generally north over the next five days or so.

This evenings latest GOES 16 infrared imagery of Hurricane Jose, showing the storm located north of Puerto Rico with very cold cloud tops and a sheared appearance to the system. Jose should track generally north over the next five days or so.

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Have a great evening!

Steve Copertino

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Watching the Remnants of Hurricane Irma Over Georgia

Good Evening! 

Hurricane Irma battered the Florida peninsula yesterday, first making landfall on the Florida Keys as a Category 4, then again later in the day near Naples as a Category 3. Though information is still rolling in on the extent of the damage in the state, it is pretty obvious that the entire state of Florida has been affected to some degree. After its final landfall in Florida, the storm began to expand its radius of tropical storm force winds quite a bit as the mid level system from Canada began to interact with the hurricane and started some extra-tropical processes. This only worsened the already massive storm surge that the hurricane carried with it during its long trek across the Atlantic. Places as far north as Charleston experienced storm-surge related damage, as well as power outages from Irma’s massive circulation. As is common with many intense hurricanes when they hit land, the amount of momentum that the storm had built up over the past two weeks will take some time to spin down, and that has been very evident today on radar and satellite.  If we look at radar images from the south, we can see a large area of rotation associated with the decaying low level circulation of Irma, as well as the more pronounced mid level circulation. This mid level circulation has been responsible for mixing down strong wind gusts to hurricane-force today across portions of the southeast, causing tree damage and numerous power outages.

Irma will continue to weaken over the next day or so, as it makes its way into the Tennessee River valley by Tuesday afternoon. The storm will be fully-extra-tropical (meaning that other process are sustaining the wind and convection and the storm in no longer fed by its warm-core) and quite large in nature. Showers and thunderstorms should extend all the way from Arkansas to portions of the southern Mid-Atlantic states like Virginia and Maryland. Some of the stronger showers and storms may be able to mix down some residual tropical storm strength gusts, and will also be capable of producing tropical downpours which may caused localized flooding of poor drainage areas and perhaps on roads. There is also a risk of tornadoes with any cells coming in from the feeder bands over the Atlantic. There have been some strong signatures observed over water during the past 24 hours, and a tornado watch has been issued for portions of the Southeast.

Please check with your local NWS office to stay on top of any watches or warnings that may be issued once the NHC declares the storm “post-tropical” and hands over the tracking to the folks at the Weather Prediction Center.

Hi-res Base Reflectivity imagery of the remnants of Hurricane Irma over the Southeast US

Hi-res Base Reflectivity imagery of the remnants of Hurricane Irma over the Southeast US

As Irma winds down late Tuesday and into Wednesday as the low begins to fully occlude and fill in, a warm front will progress from west to east over the Mid Atlantic states, and eventually into the Northeast. This front will begin to slow as it moves through Pennsylvania on Wednesday, due to the residual high pressure system just off the coast of the Mid Atlantic. This will cause numerous showers to form over the area, but as tropical moisture begins to fade, these showers should be on the more typical side, with steady rain and generally cloudy conditions expected.

As of right now, the most unsettled day across the eastern half of the nation appears to be on Thursday, when a little more surface heating may take place just ahead of the main area of mid level energy, and this could create a marginally unstable air mass supportive of weak thunderstorms and isolated downpours. Friday may feature more showers and possibly some thunderstorms over much of the Mid Atlantic and Northeastern states, but the overall area of coverage will depend on just how strong the mid level energy remains as it meanders over the next few days. Dry conditions may return this weekend, as an area of high pressure begins to build in from the west, which should kick the remnants of Irma out of the area and allow for more stable and clear conditions.

Evolution of the mid level remnants of Hurricane Irma over the next few days as it meanders across the eastern third of the country

Evolution of the mid level remnants of Hurricane Irma over the next few days as it meanders across the eastern third of the country

Hurricane Jose Wandering Over the Open Atlantic

Hurricane Jose is still out and about over the Atlantic, located to the north of Hispaniola and Puerto Rico. Jose has been experiencing significant wind shear due to the very rapid expansion of Irma’s outflow once it began to undergo an extra-tropical transition. Even in the face of this shear, the storm has been able to maintain hurricane intensity, and currently has winds of around 100 mph. The storm may continue to weaken as it begins to execute a very complex loop over the next few days due to a break-down of the steering currents from the remnants of Irma. This pattern is forecast to last until Friday or so, when the hurricane will once again be located just north of the Bahamas. It is at this point that the models begin to diverge significantly. Some models have the storm taking a hard right and heading out to sea, and others have Jose maintaining a more westerly motion by this weekends, which would put it uncomfortably close to the southeast US. This scenario would result in the storm also encountering more favorable conditions for re-intensification as an upper level high would be allowed to rebuild overhead.

While it is much too early to say what the overall outcome will be, there is plenty of time to watch this storm as it churns over the open waters of the Atlantic, with the only concerns being increased wave action and rip-tides. We will have more on this storm regardless if it becomes a legitimate threat to the east coast over the next few days!

Latest GOES 16 IR imagery showing Jose getting beaten up by shear from now Tropical Storm Irma's outflow (courtesy of weather.us)

Latest GOES 16 IR imagery showing Jose getting beaten up by shear from now Tropical Storm Irma’s outflow (courtesy of weather.us)

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Have a great evening!

Steve Copertino

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Hurricane Irma Eyes Down Florida, Jose and Katia Become Life-Threatening Hurricanes

Good Evening

Since our last update, the Atlantic has racked up more records that it would take too much time to list all of them here. There have been some major changes with our storms, and unfortunately they are not welcome changes. To help get the word out about these potentially catastrophic hurricanes, we have temporarily removed our paywall. We hope everyone stays safe over the next few days during these exceptionally dangerous times.

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Starting off with the most imminent threat to land, we have Hurricane Katia, which is nearing the coast of Veracruz in Mexico. Katia has steadily organized into a hurricane with winds of 105 miles per hour, and recon will be heading into the storm shortly to get a better understanding of the storms strength before it makes landfall later this evening and into early tomorrow morning. While Katia will pose a formidable storm surge and wind threat to the immediate coast, the main threat with the storm will be the threat for life-threatening mud slides triggered by very heavy rainfall as the storm moves inland. Though the storm is relatively small, it still could produce 8-14″ of rain across portions of Mexico, which is more than enough to cause serious issues for locals.

This afternoons HWRF model showing potential rainfall accumulations over portions of Mexico during the next few days. Life-thretening mud slides will be possible as the storm moves inland (Courtesy of NOAA HRD/HWRF)

This afternoons HWRF model showing potential rainfall accumulations over portions of Mexico during the next few days. Life-threatening mud slides will be possible as the storm moves inland (Courtesy of NOAA HRD/HWRF)

Katia will likely be very close, if not over Mexico by 1am Central time, so the time the cyclone has to strengthen is very short, but it would not be all that surprising if the current reconnaissance mission found that the storm had indeed become a major hurricane. While it has little impact on the overall threats from the storm, having three active major hurricanes would be a first for the Atlantic. Regardless, Katia should rapidly weaken tonight over the high terrain of Mexico, and should degenerate into a remnant low by tomorrow evening. Overall, people in the path of Katia should be aware of rapidly deteriorating conditions as early 8pm central.

GOES 16 IR shot of hurricane Katia nearing landfall over the Mexican coastline (NASA GHCC)

GOES 16 IR shot of hurricane Katia nearing landfall over the Mexican coastline (NASA GHCC)

The next storm likely to affect land is Major Hurricane Jose. Since the last time we looked at Jose it was just a minimal hurricane. Since that time, Jose has put on a very impressive bout of intensification as it was able to hold onto the pocket of low shear just behind Hurricane Irma’s expansive outflow. An earlier recon mission into the storm found that winds have dramatically increased to 150 mph, making Jose an extremely dangerous Category 4 hurricane. With Jose acquiring 150mph winds, this marks the first time in Atlantic hurricane history that back to back storms have attained 150+mph winds. As of this evening, Jose looks rather healthy, despite the storm taking on a more sheared appearance from the aforementioned outflow of Irma. Another recon plane will be in the storm shortly to get an intensity sample, but it seems likely that the storm will at least maintain major hurricane status while it nears the islands.

IR loop of Major Hurricane Jose approaching the Leeward islands with 150 mph winds

IR loop of Major Hurricane Jose approaching the Leeward islands with 150 mph winds

Jose may come uncomfortably close to the northern Leeward islands tomorrow afternoon, the same area which Irma quite literally wiped out just a few days ago. With little infrastructure left on the islands of Barbuda and Anguilla, even sustained hurricane force winds will cause massive issues for those left on the islands. This afternoons model guidance took the storm just north of the islands, which would spare them the tight core of the storm, which is good news, but the islands may still experience very heavy squalls, intense wave action, and occasional gusts to hurricane force during the day tomorrow. As I write this, it seems that the storm is really starting to show signs of weakening a bit as the cloud tops begin to warm and the system quickly becoming lopsided, despite the eye remaining quite visible.  We will have to see if this trend continues, as this would lead to the storm possibly weakening quite a bit by the time it reaches the islands, which would be very welcome news.

After the storm moves north of the islands, the eventual track of the hurricane becomes very uncertain. As Irma eventually makes landfall somewhere along the Florida peninsula, it will begin to reshape the steering currents over the western Atlantic. This could cause the storm to begin to head east and just south of Bermuda by the middle of next week. At that point, another ridge of high pressure may try to build in overhead and cause the storm to track in an erratic fashion. For this reason, we will still have to keep a weary eye on Jose over the next week or so.

This evenings HWRF model showing winds from Jose coming dangerously close to the islands devastated by Hurricane Irma

This evenings HWRF model showing winds from Jose coming dangerously close to the islands devastated by Hurricane Irma

Once again, we move onto Hurricane Irma

Irma has gone through a lengthy eyewall replacement cycle over the past day, which has allowed for the storm to weaken from its 185 mph intensity down to a 155 mph Category 4. Irma is still a very powerful hurricane, and those who think that just because the storm has weakened over the past day or so means that it will be less impactful in the long run is severely mistaken. In fact, there is some data that would suggest that the storm has begun to re-intensify just north of the Cuban coast-potentially back to Category 5 levels. This will have to be confirmed by the NHC in the coming hours.

Over the past 24 hours, the majority of the global models and their ensembles have shifted west, away from SE Florida, and now have SW Florida, and then the western coast in the direct path of this system. Additionally, radar observations show that it is almost certain that the center of Irma will make landfall on the Cuban coastline later tonight. This is a huge change from prior forecasts, and just how long the storm stays over Cuba will determine just how much the storm will weaken. As of this time it seems like Irma will make landfall on the Cuban coast early Saturday morning and could remain over land until later in the day tomorrow. Afterwards, the storm would likely be exiting into a region of extreme oceanic heat content and favorable upper level conditions. Most of the high resolution models, including the new “Deep Thunder” IBM model has Irma rapidly intensifying once it leaves the Cuban coast. I am hesitant to say that Irma will be able to intensify quickly as soon as it leaves the coast due to the fact that this is a very large storm with a very large core, and it may take some time to reorganize, depending  on how much damage is done. It is however, likely to at least regain some strength, possibly back to a high-end Category 4 as it nears Florida.

Current GOES 16 shot of Hurricane Irma with 155 mph winds just off the Cuban coast

Current GOES 16 shot of Hurricane Irma with 155 mph winds just off the Cuban coast

With regards to the track of Irma, it now seems likely that Miami will not get the brunt of the storm. Areas in SW Florida, including the Florida Keys may see the full extent of Irma on Sunday, with extremely damaging winds, deadly storm surge, and flash flooding. The models have been shifting west all day, and we may very well see more shifts this evening, but the chances are drastically increasing that the west coast of Florida will experience the worst of the storm. Those in the path will have to monitor Irma very closely over the next few days, and stay tuned for further updates as new data become available. We will have more on this developing situation tomorrow for the public.

****When making decisions, always consult the National Hurricane Center, your local National Weather Service, government officials, and local Emergency Managers.****

Latest storm-specific model tracks for Irma, showing a considerable shift away from SE FL (Courtesy of weatherbell)

Latest storm-specific model tracks for Irma, showing a considerable shift away from SE FL (Courtesy of weatherbell)

For more information and posts like this one, make sure you sign up for Premium Forecasts — where multiple detailed articles, videos, and interactives are posted each day. Also, come interact with our staff and many other weather enthusiasts at 33andrain.com!

Have a great evening!

Steve Copertino