Fiona Heads East, Next Wave Could be a Threat

 Good morning all!

The Atlantic tropics got off to a very quiet start this season, but have been heating up recently.  

Fiona

Hurricane Fiona, after lashing Puerto Rico with devastating flooding (AP Article) and knocking out the power grid, is now near the Turks and Caicos Islands as a Category 3 hurricane. The storm will recurve well East of the Continental U.S., but could be a threat to the island of Bermuda, and also maritime Canada as it transitions into a large exatropical storm in a few days.

Figure 1: 5-day NHC forecast for Hurricane Fiona (https://www.nhc.noaa.gov/)

Next Wave(s): Invest 98L

There is one system way out in the North-Central Atlantic that could become a brief TS, but won't bother anyone.

The system I am most concerned about is a wave currently just north of South America, moving towards the Windward Islands and Caribbean. This was just tagged as "Invest 98L" this morning, and is currently given a 50% chance of development by NHC.

Figure 2: NHC Tropical Weather Outlook from 8 am Tue, Sep 20, 2022, showing Fiona and two other systems of interest.

Figure 3: Infrared satellite image of Invest 98L (https://www.weathernerds.org/)

98L is forecast to move near the Windward Islands, Trinidad, and Tobago, and into the far SE Caribbean over the next few days. It could well develop into a tropical storm then.

After that, the storm is likely to move through the Caribbean, where conditions look favorable for intensification, with light upper level winds and warm waters.

It's still too far out to be certain about the track, but "ensembles" (a bunch of slightly different versions of the same model, run to give an idea of the possible spread) show it could be anywhere from near Cuba to near Honduras in a week.

Figure 4: ECMWF Ensemble Forecasts for Fiona (Top) and 98L (Bottom). (https://www.weathernerds.org/)

Lots to sort out still, but the pattern does suggest a possible Gulf threat in 7-10 days. No need to panic yet, but I recommend making sure your hurricane plan is ready to go anywhere along the Gulf Coast and Florida, and keep a close eye on the tropics as we round out September.

Andy

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Invest 94L a Chance of an Early-Season Storm. Just Something to Watch for Now.

Invest 94L in the Central Atlantic

Overview

Happy Friday evening everyone! There is a tropical wave in the Central Atlantic ("Invest 94L") that bears watching. It's pretty early for stuff to develop out there but this has a chance to develop as it approaches the Caribbean. Side note - what is an "Invest"? Basically - that's what NHC calls a disturbance that they think *might* form into a tropical depression or more, but it's not organized enough yet. In this case, they are giving it a 60% (medium) chance of becoming a TD within 5 days:

Image 1: NHC's Tropical Weather Outlook From 2pm Friday, June 24, 2022

https://www.nhc.noaa.gov/gtwo.php?basin=atlc&fdays=5

Forecast for 94L

Right now the system is fairly disorganized. It will take some time to get together. Most models are bringing it into the Southern Caribbean. It could even get close to the "ABC Islands", which is pretty rare ever, especially this time of year. We'll have to see. Conditions look favorable ahead of it but it may take some time to get organized. Down the road, it could head towards Nicaragua and Honduras, or the Yucatan Peninsula of Mexico. Too far out to say if it will be a US threat at all, but hopefully the big ridge of high pressure that's made things so darn hot over the Southern US will also act to keep this south of the states.

Image 2: Infrared satellite image of Invest 94L as of 5:15 PM EDT on Friday, June 24, 2022

https://www.weathernerds.org/satellite

Image 3: ECMWF "ensemble" for Invest 94L, showing some of the possible tracks in the Caribbean. This will likely change some over time.

https://www.weathernerds.org/models/ecens.html

So in summary, nothing to panic about now, but a good reminder to make sure your hurricane plan is ready to go, as we approach the peak of hurricane season! Always pay attention to www.nhc.noaa.gov for the latest, official information. Stay safe out there!

Andy