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.
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.
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.
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.
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.
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!
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Have a great weekend!