Sorry I didn't update yesterday... did I miss anything? ;-)
Don't know about you but generally speaking, I'm looking forward to: science-based decisions (as we all do during hurricane season); a return to civility in politics and in general; more time for things other that what is coming out of DC; a President who has respect for the office and doesn't take to social media to express his every thought; and of course, the refreshing return of complete sentences and proper grammer! :-)
But before all that, I'm looking at Tropical Storm Eta - not to be confused with Tropical Depression Etau which is in the South China Sea and currently has winds of 35mph - expected to make landfall in Vietnam tomorrow as a Tropical Storm.
It's crossed Cuba and is now at 23.9N, 79.5W, heading NW at 14mph...
The convection is currently a lot weaker than it was earlier, even though it is over the warm water of the Straits of Florida:
This is because of the dry air I mentioned couple of days ago. Here is the water vapor satellite imagery in the lower levels of the troposphere:
You can see that yellow/orange air - the dry stuff - weaving into the storm as it came off Cuba. What's interesting is that although it is mostly to the south and east, it is now wrapping around to the north - over southern Florida. If that persists, this will be a bit weaker than currently forecast. The upper level water vapor also shows some dry air:
Which means this is throughout the troposphere. This is a jolly good thing as it keeps the storm a little weaker.
The vorticity (circulation) is also not very well formed yet - and that's because it took a little hit crossing Cuba (as expected). The lower half of the troposphere (850mb and 500mb) shows it's not quite as in shape as it was before entering Cuba and is a bit of a splodge really that extends to the Yucatan peninsula:
At the mid-troposphere (500mb):
The upper troposphere (200mb) looks like it is part of a front that extends southwest and then northwards:
So, although the vorticity signal isn't what we expect to see with a Tropical Storm, it does have some throughout the troposphere which means it will be windy even if there isn't as much convection as we'd normally see with this.
It is going over the warm waters of the Florida Current and the forecast is that it will be over the Loop Current - these are areas where the water is also warm with depth so there is plenty to sustain a storm. This is why the forecast calls for a strengthening to a weak cat 1 in a day or so.
There is still some wind shear which we can see as the clouds are streaming merrily off to the east in the satellite imagery. However, it looks like this will decrease as the storm moves to the west and over the Keys/into the Gulf, so that will also allow it to strengthen as it moves westward.
Storm surge is from the tidesandcurrents.noaa.gov website. As usual, scrolling in on the map and clicking stations in the area, I see that Key West is just over 1 ft above normal and Virginia Key/Biscayne Bay has water levels about 1.5 ft above normal:
Of course the track can be anywhere in that Cone of Uncertainty, so it may actually go over the Keys directly or shift a little to the north or south so be ready for any of those possibilities. Also, your local emergency managers are the bees knees - they have the best local information so if I were there, I'd be listening to them. But knowing people in the Keys, I am fairly sure you have your bottles of beverages and are fully prepared for this! Just stay away from the water!
Be safe out there!
Ciao for now,
J.
Twitter: jyovianstorm
These remarks are just what I think/see regarding tropical storms - not the opinion of any organization I represent. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast and local weather service announcements. This is not an official forecast. If I "run away, run away" (Monty Python), I'll let you know.
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