Tropical Storm Eta

[yoda]

Tropical Depression Eta Discussion Number  19
NWS National Hurricane Center Miami FL       AL292020
300 AM CST Thu Nov 05 2020

Eta has become very disorganized due to its interaction with the 
land mass of Central America, and may no longer have a surface 
circulation.  Based on a few surface observations, the maximum winds 
are estimated to be around 25 kt over the water to the north of 
Honduras.  Eta is likely to degenerate into a post-tropical low very 
soon, if it hasn't done so already.  Since the low is predicted to 
move into the northwestern Caribbean Sea by tomorrow night, some 
restrengthening is forecast to begin by the weekend.  However the 
expected broad nature of the cyclone and stronger vertical shear are 
likely to limit strengthening over the next several days.  The 
official intensity forecast is similar to the latest model 
consensus.

The center is extremely difficult to locate at this time, but based 
on continuity the initial motion is estimated to be 300/7 kt.  Eta, 
or its post-tropical remnant low/trough, should continue to move 
over land today, and then turn northward tonight while moving along 
the eastern side of a broader gyre.  This will take the system into 
the Gulf of Honduras and over the northwestern Caribbean Sea on 
Friday.  A negatively-tilted 500-mb trough/low developing over the 
Gulf of Mexico should induce a generally northeastward motion for 
the next 2-3 days and take the cyclone across portions of Cuba in 
3-4 days.  Thereafter, the system is forecast to rotate cyclonically 
around the eastern side of the 500 mb low and turn northwestward to 
westward by the end of the forecast period.  The official forecast 
is a blend of the latest GFS and ECMWF predictions, but leans toward 
the latter model.  This track could take the system near or over 
portions of extreme southern Florida by late this weekend or early 
next week, but there is low confidence in the forecast, especially 
at 3-5 days. 


Key Messages:

1. Through Monday morning, heavy rainfall from Eta will lead to
catastrophic, life-threatening flash flooding and river flooding
across portions of Central America, along with landslides in areas
of higher terrain.  Flash and river flooding is also possible across
Jamaica, southeast Mexico, the Cayman Islands and western Cuba.

2. Eta is forecast to regain tropical storm strength over the
northwestern Caribbean Sea late this week. Although the details of
the future track and intensity of Eta are uncertain, there is an
increasing risk of impacts from wind and rainfall in portions of
Cuba, southern Florida and the Florida Keys this weekend and early
next week.


FORECAST POSITIONS AND MAX WINDS

INIT  05/0900Z 14.5N  87.0W   25 KT  30 MPH
 12H  05/1800Z 15.0N  87.8W   25 KT  30 MPH...POST-TROP/REMNT LOW
 24H  06/0600Z 16.2N  87.8W   30 KT  35 MPH...POST-TROP/REMNT LOW
 36H  06/1800Z 17.4N  86.3W   35 KT  40 MPH...TROPICAL CYCLONE
 48H  07/0600Z 18.5N  84.7W   40 KT  45 MPH
 60H  07/1800Z 19.6N  82.9W   45 KT  50 MPH
 72H  08/0600Z 21.0N  81.0W   50 KT  60 MPH
 96H  09/0600Z 23.5N  79.5W   50 KT  60 MPH
120H  10/0600Z 24.5N  81.5W   55 KT  65 MPH

$$
Forecaster Pasch

[stormwatcherJ]

Wow, this thread has gone silent... everyone watching the election maybe??

[dan11295]

2 minutes ago, stormwatcherJ said:

Wow, this thread has gone silent... everyone watching the election maybe??

People are kind of done with the tropics I sense, plus its kind of not doing anything at the moment.

[Prospero]

25 minutes ago, stormwatcherJ said:

Wow, this thread has gone silent... everyone watching the election maybe??

I keep coming back, but until it gets back over water I guess nobody is excited. But here in Florida, we are paying attention.

[cptcatz]

I'm in Boca Raton so watching it carefully.  But there's not much going on right now.  Although I just checked out the satellite and it looks like a whole lot of convection is firing up over the water right now, maybe a spin starting to form?

[turtlehurricane]

An extremely interesting period of weather has begun here. For days we were getting wind gusts of 30-40 mph associated with our first cold front of the year, a cold front which didn't even drop the low temps below 70, so it wasn't enough to cool the waters. 

Indeed, as I write this FLL is gusting to 37 mph.

Now the front is lifting back north and the moisture is returning. It started yesterday with some brief showers coming in off the ocean. Overnight these showers turned into quick moving heavy downpours. Now the radar is really starting to light up, and the NWS says there's a flooding threat even today, and this is just the beginning, with the flood threat increasing overnight and into tomorrow. 

Basically, the rains associated with this system are already underway, and conditions will deteriorate until Eta makes its closest approach on Monday or so. 

It really is up in the air on what exactly will happen with ETA, and if any damaging winds will reach South Florida, but the rain threat is already a certainty. 

[stormwatcherJ]

What are chances of Eta moving east of Florida?

[hawkeye_wx]

Latest Euro has Eta becoming a solid hurricane again in the central gulf, but then drifts north and collapses.

[cptcatz]

No idea if there's a LLC but there's a tight vortex in the upper level clouds visible at 18N 82.5W.  Anything to make out of that?

[Modfan2]

Already heavy rain here in S FL with banding setting up of the ocean; it might be a long 7 days.

[turtlehurricane]

18z GFS takes Eta right through Southeast Florida. First model run in awhile which has shown a direct hit here. 

Hour 78... looks like a hurricane too. That would be crazy and awesome. 

[Prospero]

4 minutes ago, turtlehurricane said:

18z GFS takes Eta right through Southeast Florida. First model run in awhile which has shown a direct hit here. 

Hour 78... looks like a hurricane too. That would be crazy and awesome. 

Wouldn't be surprised if we are watching models in December this year.

If we get a Tropical Storm out of this in Tampa Bay, we might feel like we finally have some immunity for the rest of the season...

But Louisiana doesn't seem to get immune no matter what.

[BombsAway1288]

4 hours ago, hawkeye_wx said:

Latest Euro has Eta becoming a solid hurricane again in the central gulf, but then drifts north and collapses.

The way the operational's have handled TC's in the medium-long range (even short-range) this year, I would be taking anything they show with a grain of salt.

[cptcatz]

18z HWRF and HMON are also trending east with the HMON bringing it right into Biscayne Bay at 982 mb.

[Prospero]

Quote

DISCUSSION AND OUTLOOK
----------------------
At 600 PM CST (0000 UTC), the center of Tropical Depression Eta was
located near latitude 16.0 North, longitude 87.8 West. The
depression is moving toward the north-northwest near 8 mph (13
km/h), and a turn toward the north is forecast during the next
several hours.  A turn toward the northeast is expected on Friday,
with this motion continuing through Saturday night.  On the forecast
track, the center of Eta will be over the western Caribbean Sea
through Friday, approach the Cayman Islands Saturday and Saturday
night, and be near Cuba on Sunday.

Is it over water yet? Looks like it:

[Modfan2]

Models this evening still show a low end Cat 1 into S FL and then some point west to the gulf; I think the NHC will adjust their cone back north tomorrow 

[Prospero]

Anxious for the sats to start to show something pop up.

[Prospero]

The most fun model to watch for 2020 is the GFS Para. I hope it ends up someday as the "go to" model.

 

[Prospero]

Models are beginning to tighten up. Exciting, yet not great news for Florida. Models have been better this year than any year I remember.

My position for our home and Tampa Bay area is always, "Be as strong as possible without power going out, loss of life, and unreasonable cleanup expense."

[dbullsfan]

Mostly a rain event for Florida it appears but still a ways out and it is still 2020

[cptcatz]

30 minutes ago, dbullsfan said:

Mostly a rain event for Florida it appears but still a ways out and it is still 2020

Heavy rain bands will start moving through Saturday morning and might continue through Tuesday.  That, plus 40-60 mph winds could easily knock trees over.  Could be significant power outages.

[NorthHillsWx]

Though it’s tough to see a defined center at this point, Eta is generating a large blowup of convection this morning

[Windspeed]

[Windspeed]

Visible since daybreak...

[NorthHillsWx]

7 minutes ago, Windspeed said:

Visible since daybreak...

You can faintly see some westerly motion on the southern end of convection but, as expected, the system looks extremely strung out. With a consolidated area of convection ongoing though this isn’t in the worst shape considering the time it spent over land. Would not shock me to see it organize relatively quickly today. Shear for the moment isn’t terrible and it already has a weak circulation and is back over water

[NorthHillsWx]

19 minutes ago, Windspeed said:

 

Wow. Didn’t the worst of the eyewall pass to their south too? I know eta wasn’t at peak strength when it made landfall but it definitely had completed its ERC and had a rapidly improving sat presentation not to mention the time it spent raking the coast as it crawled onshore. 140 mph LF is nothing to shake your head at. If there had been more major population centers there this would’ve been disastrous

[turtlehurricane]

The rain threat has underperformed here overnight, but notably Southeast Florida has just been placed under a Flood Watch and a Wind Advisory. NWS thinks the flooding threat and gusty winds will really kick off tonight. 

The frontal boundary over South Florida along with Tropical
  Cyclone Eta forecast by NHC to move through the Florida Straits
  and Florida Keys this weekend will help to bring the very deep
  tropical moisture into South Florida from the Caribbean Sea. The
  grounds are also still somewhat saturated from the late October
  rains over the eastern areas of South Florida. Therefore, it
  will not take much to cause flooding over the region especially
  over the east coast metro areas. At this time, it looks like 5
  to 10 inches are possible over the east coast metro areas
  tapering down to 2 to 5 inches for the west coast metro areas
  with locally higher amounts where showers and thunderstorms
  train through Tuesday. Therefore, a Flood Watch has been issued
  for the east coast metro areas from tonight through Tuesday
  evening.

Models seem to be quite consistent over the last day about a Southeast Florida landfall of a strong tropical storm or even Cat 1 Hurricane. We will see, it's still up in the air and the track forecast is complex and uncertain, especially until we start getting real center fixes. 

[turtlehurricane]

I just noticed that since were past the time change that NHC advisories are coming out at 10 AM. I've never seen that before, cause there's never been a storm this late in the season that was a threat.

NHC forecast track has Eta making landfall in the Keys and the southernmost Everglades Sunday night, but of course it will be a fairly large system, and tropical storm force winds will mostly be on the north side. Tropical storm watches may be raised as soon as 5 PM, or 10 PM at the latest, if trends continue. 

There is an increasing risk of impacts from wind and flash and 
urban flooding due to heavy rainfall in portions of southern 
Florida, the Florida Keys and portions of the Bahamas this weekend 
and early next week. Tropical Storm or Hurricane Watches will likely 
be issued later today or tonight for a portion of this area.

The new forecast track requires a Tropical Storm Warning for the 
Cayman Islands at this time, and a Tropical Storm Watch for 
portions of Cuba.  Watches may be required for portions of south 
Florida and the Florida Keys later today or tonight.

[NorthHillsWx]

1 hour ago, turtlehurricane said:

Models seem to be quite consistent over the last day about a Southeast Florida landfall of a strong tropical storm or even Cat 1 Hurricane. We will see, it's still up in the air and the track forecast is complex and uncertain, especially until we start getting real center fixes. 

Models are slowly coming into better agreement and this looks like it will be a fairly significant impacts for southern Florida. It will not be a high end event by any means but given the interaction with the closed low this should take on at least some subtropical characteristics which will lead to an enhanced wind field well away from the center and a long duration onshore flow for the east coast of Florida. Widespread power outages, especially given the antecedent rain and large wind field, are on the table too. This, meteorologically, is going to be an interesting one to watch as it may go from purely tropical to a hybrid on our doorstep and a strong hybrid at that. A minimal subtropical hurricane is certainly on the table with this evolution before dry air kills it in the eastern gulf. These subtropical attributes will allow it to pass over Cuba mostly unscathed and also develop through the keys despite land interaction. This is not going to be a high end wind event, I’m thinking it does make another run at minimal hurricane, but I do think it will bring widespread impacts to southern Florida and may be a decent storm for those there due to duration 

[the ghost of leroy]

Zzzzzz