ATL: NATE - Post Tropical - Discussion

[kevin mathis]

While the tracks are reasonable, I still find the strength forecasts from both models to be an utter mess

Given the current look of the system and its trek towards Nic/Hon I feel there is a distinct possibility the would-be Nate never recovers enough to take advantage of the conditions ahead of it. Frankly,are the condidtions going to be that ideal. Models have done a poor job in every aspect to this storm. Fluctuating between a weak storm with hostile environment, to a strong storm with almost ideal conditions aloft. We all hang our hats on the newest run of almost every model, like the newest suite of runs is now right and the last ones that we though were right are now wrong. That is why this is so fun. I can guarantee this...Nate will form or not form and go to LA or FL as a wave,TS or H. I'm quite sure of this. No matter what comes of Nate, he will not change his track or intensity based on 0z,6z,12z,18z changes in model runs.

[Jelff]

NOAA's cone of uncertainty has shifted west a bit.

Also I added NASA's sea surface temperature data as a basemap called (wait for it) "Sea_surface_temperature". This basemap will always display data for the day before you turn this basemap on. It takes awhile for the data to get processed and posted to NASA's GIS server. So far today this basemap is not displaying any sea surface temperature data for yesterday. I expect if I try to turn this basemap on later today then this data (for yesterday) will appear. And if this is the first time you are seeing this map, the 'basemap' button is next to the "Menu" button.

This is the same Google + GIS hurricane map that I have previously posted. However I tweaked the GIS layers that are 'on' when the map opens.

Want to know how to make your own custom map link? Please read the "Map Tips".

Map link: https://goo.gl/3nbpMD

Long version of the same map link: https://mappingsupport.com/p/gmap4.php? ... ricane.txt

[toad strangler]

06z GFS as others have said show maybe just a wave and perhaps an open one at landfall. Amazing.

[NDG]

looking at satellite, it looks like shear is 20-25 kts right now from the SW. Major shear forecast bust by the models

Yesterday's 12z Euro forecasted 20-25 knot UL winds over TD 16 this morning, so that's about right, because the trough is not yet out of the way. Not until it pushes further west will the better UL winds will get closer to TD 16 over the NW Caribbean and GOM.

[WeatherGuesser]

there is a chance, albeit a small one, this never does become Nate.

It that proves to be, the current 5 day cone may have caused a lot of unnecessary stress in LA.

[tropicwatch]

That is quite the shift west this morning for the NHC.

[Emmett_Brown]

This is officially Nate now at the NHC website per the 8am EDT advisory. 40 mph, 999mb

[NDG]

The way storms have strengthen all the sudden this year, I really doubt that TD 16 will not become Nate or hurricane. Not unless it was to stay over C.A. and die out, lol.

[Lane]

TROPICAL DEPRESSION BECOMES TROPICAL STORM NATE NEAR THE
COAST OF NICARAGUA...
...FLOODING RAINS EXPECTED OVER PORTIONS OF CENTRAL AMERICA...


SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...13.9N 83.4W
ABOUT 10 MI...15 KM S OF PUERTO CABEZAS NICARAGUA
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 8 MPH...13 KM/H
MINIMUM CENTRAL PRESSURE...999 MB...29.50 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
* Sandy Bay Sirpi Nicaragua to Punta Castilla Honduras

A Hurricane Watch is in effect for...
* Punta Herrero to Rio Lagartos Mexico

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

Interests elsewhere in Honduras, the Bay Islands, western Cuba and
the Yucatan Peninsula should monitor the progress of Nate.

For storm information specific to your area, please monitor
products issued by your national meteorological service.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 800 AM EDT (1200 UTC), the center of Tropical Storm Nate was
located near latitude 13.9 North, longitude 83.4 West. Nate is
moving toward the northwest near 8 mph (13 km/h), and this motion is
expected to continue this morning. A north-northwestward motion at
a faster forward speed is forecast to begin later today and continue
through Friday night. On the forecast track, the center of Nate
should move across northeastern Nicaragua and eastern Honduras today
and then over the northwestern Caribbean Sea tonight and Friday.
The center is expected to approach the coast of the Yucatan
peninsula late Friday.

Maximum sustained winds are near 40 mph (65 km/h) with higher
gusts. Little change in strength is expected today as the center
of Nate moves across northeastern Nicaragua and eastern Honduras.
Strengthening is likely over the northwestern Caribbean Sea tonight
and Friday.

Tropical-storm-force winds extend outward up to 60 miles (95 km)
mainly over water to the east of the center.

The estimated minimum central pressure is 999 mb (29.50 inches).
Puerto Cabezas recently reported a pressure of 1001 mb
(29.56 inches)


HAZARDS AFFECTING LAND
----------------------
RAINFALL: Nate is expected to produce the following rain
accumulations through Friday night:

Nicaragua...15 to 20 inches, isolated 30 inches
Costa Rica and Panama...5 to 10 inches, isolated 20 inches
Honduras and Belize...2 to 5 inches, isolated 8 inches
Eastern portions of the Yucatan peninsula...4 to 8 inches, isolated
12 inches

Heavy rainfall will occur over a wide area, including locations well
away from the center along the Pacific coast of Central America.
This rainfall could cause life-threatening flash floods and
mudslides.

WIND: Tropical storm conditions are expected within portions of the
warning area in Nicaragua and Honduras today and tonight. Tropical
storm and hurricane conditions are possible within the watch area in
Mexico beginning late Friday.

SURF: Swells generated by Nate are affecting portions of the coast
of Nicaragua, and will begin to affect other land areas around the
northwestern Caribbean later this week. These swells are likely to
cause life-threatening surf and rip current conditions. Please
consult products from your local weather office.

[NDG]

The way storms have strengthen all the sudden this year, I really doubt that TD 16 will not become Nate or hurricane. Not unless it was to stay over C.A. and die out, lol.

Well never mind, it is now Nate.

[LarryWx]

New advisory has 5 mb lower SLP and it has moved much more n than w. Is movement more NNW now or not?

[stormlover2013]

High pressure looks stronger towards, doesn't surprise me with a la landfall with what models are showing we still got time for it to flip flop though

[BucMan2]

Good morning-

So is there anything synoptically that could move this back east?

Craig

[MGC]

Katrina like shift in the forecast track by the NHC....GFS looks to be correct with the low forming in the Florida Straights. Looks like I'll start getting the yard stuff put away.....MGC

[LarryWx]

8:00 AM EDT Thu Oct 5
Location: 13.9°N 83.4°W
Moving: NW at 8 mph
Min pressure: 999 mb
Max sustained: 40 mph

Contrast this to 5 AM with it at 13.3N, 83.3W and 1004 mb. So, 5 mb stronger in just 3 hours and movement of only 0.1 W while moving 0.6 N. Comments?

[tolakram]

I did not see the GFS solution of 5 or 6 separate areas of vorticity, either with Sixteen or the low near Florida. It may have been sniffing out the issues with a system being embedded in a larger gyre, but the solution still can't be trusted IMO. It also may have a more accurate track, but the way it arrived at that track cannot be called correct IMO. The GFS did pick out the voriticity (well, one of them anyway) in the Florida straits, something the euro now shows. This may be the feature that prevents this system from getting very strong.

[ronjon]

While the tracks are reasonable, I still find the strength forecasts from both models to be an utter mess

Given the current look of the system and its trek towards Nic/Hon I feel there is a distinct possibility the would-be Nate never recovers enough to take advantage of the conditions ahead of it. Frankly,are the condidtions going to be that ideal. Models have done a poor job in every aspect to this storm. Fluctuating between a weak storm with hostile environment, to a strong storm with almost ideal conditions aloft. We all hang our hats on the newest run of almost every model, like the newest suite of runs is now right and the last ones that we though were right are now wrong. That is why this is so fun. I can guarantee this...Nate will form or not form and go to LA or FL as a wave,TS or H. I'm quite sure of this. No matter what comes of Nate, he will not change his track or intensity based on 0z,6z,12z,18z changes in model runs.

I wouldn't jump for joy yet - 06z HWRF has a 970 mb cane into NO.

https://www.tropicaltidbits.com/analysis/models/?model=hwrf&region=16L&pkg=mslp_pcpn_frzn&runtime=2017100506&fh=6&xpos=0&ypos=0

[stormreader]

How about that, the Euro now looks more like the crazy GFS runs.

[im g]https://i.imgur.com/WoPD61a.gif[/img]

Yes indeed. Part of what made the GFS less believable, I think, is that many automatically assume a strong NE move in the Gulf in October. But it's just not always how this plays out. Same thing last year with Mathew. Many assumed ( along with early model runs) that Mathew (in early October) just couldn't make enough of a west move to actually approach the East coast of the U.S. But early October, storms can still have significant west (or lack of east components) for longer than many think. Sort of a prevailing east bias that many have for October storms.

[gatorcane]

Kudos to the GFS. This may end up being nothing significant. On the other hand the model is showing something potentially significant in the same area in 12 to 14 days that has my interest.

[ronjon]

Katrina like shift in the forecast track by the NHC....GFS looks to be correct with the low forming in the Florida Straights. Looks like I'll start getting the yard stuff put away.....MGC

06z HWRF, usually on the strong side of guidance, has a 970 mb cane landfalling just east of NO.