2021 Atlantic Hurricane Season Tracking Thread

[mappy]

1 minute ago, WxWatcher007 said:

Thinking this is a late next week/weekend deal so you should be fine. 

But…you DON’T want to see tropical? That’s how I spend all my vacation time  

That's fine. Late next week looks rainy anyways, but thankfully only a day of it. 

I dont mind seeing it if it stays off the coast. When we went last time Humberto passed by one day, was still sunny on the beach, but waves were up. Otherwise, it was great.

[frd]

4 hours ago, SnowenOutThere said:

Will not verify but fun to look at.

 

Fits the pattern of the Euro weeklies which shows a robust WAR into early October. 

You just need the correct timing, but that is an odds thing. Overall, the potential is there. 

 

 

[Weather Will]

Larry will bring 2-4 ft of snow to Greenland! WB 12Z EURO…

[WxWatcher007]

GFS (and the guidance more broadly) shows nicely what I was talking about when I highlighted those three areas of interest. For the BoC/Gulf disturbance, the GFS keeps it further east as it rounds the periphery of a ridge and that gives it just enough space to develop pretty quickly into a hurricane that threatens the TX/LA coast in a few days. Still an outlier for now but can't be discounted at all. 

GFS and the 12z Euro also continues the signal for some sort of broad mess to develop off the SE US at the end of next week that would be drawn into the SE US as a ridge flexes or up the coastline as a trough advances from the midwest. Right now I'd favor some weak tropical or subtropical system, but a more focused area of vorticity would be able (I think) to modestly develop if shear continues to back off. 

With today being the official peak of the season I plan to write up a basin overview tonight. 

[AdamHLG]

Larry will bring 2-4 ft of snow to Greenland! WB 12Z EURO…

How much for Phili?


.

[Cobalt]

57 minutes ago, AdamHLG said:

How much for Phili?


.

About as much as Short Pump is getting.

[WxWatcher007]

Atlantic Basin Overview 9/10/21

The peak is here! 

It has been a very active season so far, with 7 US landfalls including the historic Category 4 landfall by Ida. There were also two additional hurricane strikes, with Grace making landfall as a Category 3 and Larry making a landfall as I type in Maritime Canada. These won't be the last landfalls of the season...

Overview
I don't really need to go into the environment. It's peak season lol and we have a cool neutral ENSO state, slightly above normal SSTs in the MDR, and while not as expansive as the extraordinary 2020 season, TCHP/OHC and D26 is very strong, especially close to home where I anticipate significant activity in the coming weeks as climo shifts from the MDR to Caribbean, Gulf, and SW Atlantic. 

 

 

Steering Pattern
After an extraordinarily busy late August and early September in the US, as expected, the pattern reshuffled, partially driven by climo IMO, to bring less risk to the US. We saw more frequent troughs and a weaker WAR, causing some quick recurves out in the MDR. The exception was Mindy, which developed quickly close to the northern Gulf coast a few days ago. 

That pattern is coming to an end. As I stated in my last outlook, I expected the pattern to return to a ridge dominant Atlantic toward the end of September. We're about a third through the month of September and we're starting to see the ensemble guidance bring back ridging in SE Canada and over the central Atlantic.

It's unclear how long that holds, but it opens the door to a return to the active landfall pattern we had just a few weeks ago if systems can track under the ridge. Let's go to the threats. 

Atlantic Areas of Interest
1) Invest 93L/Eastern MDR Wave--The wave coming off the coast of Africa has 70% development odds from the NHC. This one is not going to impact the US, but its evolution could have significant implications on another area of interest.

2) Bay of Campeche--It's a little baffling to me that this isn't an invest yet, but the NHC has odds of development at 80% within 5 days. The signal for this one continues to be a little complicated, chiefly because of proximity to land. It looks clear to me that there will be a level of development as the disturbance takes advantage of a favorable environment, including the concave nature of the BoC that should help focus vorticity.

As I said in my last update, this is a great space for disturbances to develop and I think the environment brings potential for significant intensification should development happen further east, away from the western Gulf coast. The 18z GFS showed this well and to a lesser extent the 12z Euro. This is one to watch closely, as it could be a US landfall along the TX/LA coast as the disturbance slides around the edge of a ridge. The rain signal for the region looks substantial. 

3) Bahamas/SE US--The signal here is growing too IMO. A broad disturbance from either a weak wave or upper low may find itself in an marginally favorable environment for development next week. The changing steering pattern continues to favor the disturbance being pushed into the SE or pulled up the coast. This is worth watching as things come into better focus. 

4) Trailing Eastern MDR Wave--This is a new one. There's a strong signal, especially on the EPS, that the wave after 93L rolls off of Africa and becomes a potential long track system. What happens here is closely tied to what 93L ends up doing. Some guidance has 93L hook north quickly, while other guidance, like the Euro is a bit slower with the turn.

The delay in the turn allows for 93L to moisten the environment ahead of this wave, which makes it more likely it can find a favorable environment early. In addition, this wave looks to come off of Africa much lower in latitude than 93L and travel westward as the central Atlantic ridge rebuilds, further pushing the wave west. This is the one I'm watching least, as it is still far out, but it could be something worth paying more attention to in the long term. 

 

Overall, there's no sign of the basin slowing down. After a bit of a break due to the reshuffling of the steering pattern, a combination of homebrew () focused development and a return to the ridge dominant upper level pattern increases the chances of US impacts for the foreseeable future. 

[yoda]

For our area... 00z GGEM looks mildly interesting late next week into the weekend... 00z GFS quite more so

00z Euro says meh 

[Vice-Regent]

The pattern advertised is more along the lines of "chaotic neutral" that is our pattern. Without going full on Chuck it's finally happening.

[WxWatcher007]

All four areas I referenced last night are now highlighted by the NHC. Happy peak!

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Sat Sep 11 2021

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center has issued the last advisory on 
Post-Tropical Cyclone Larry, located over the Labrador Sea. 

A tropical wave and an upper-level trough continue to produce a 
large area of disorganized showers and thunderstorms over portions 
of southeastern Mexico and the southern and central Gulf of Mexico. 
Although upper-level winds are not conducive for development 
currently, they are expected to become more favorable for the system 
during the next day or so. A tropical depression is likely to form 
on Sunday or Monday while the disturbance moves northwestward and 
then northward near the coast of northeastern Mexico.  Further 
development will be possible through the middle of next week if it 
remains over water, and interests along the western and northwestern 
Gulf coast should monitor the progress of this system.  An Air Force 
Hurricane Hunter aircraft is scheduled to investigate the system 
tomorrow.

1. Regardless of development, this disturbance is expected to produce 
heavy rain across portions of Central America and the Yucatan 
Peninsula through today which may lead to flash flooding and 
mudslides. By late this weekend, heavy rain will likely reach 
portions of the western Gulf coast, including coastal Texas and 
Louisiana through the middle of next week. Localized significant 
rainfall amounts will be possible, potentially resulting in areas of 
flash and urban flooding.
* Formation chance through 48 hours...high...80 percent.
* Formation chance through 5 days...high...90 percent.

2. Showers and thunderstorms have not become any better organized in 
association with a tropical wave located just southeast of the Cabo 
Verde Islands. Environmental conditions appear generally conducive 
for gradual development, and a tropical depression is likely to form 
late this weekend or early next week while the system moves westward 
over the far eastern Atlantic.  Regardless of development, this 
disturbance is likely to bring gusty winds and locally heavy rain 
across the Cabo Verde Islands later today and tonight.  
* Formation chance through 48 hours...medium...50 percent. 
* Formation chance through 5 days...high...70 percent.

3. Another tropical wave is expected to move off the west coast of 
Africa in a few days.  Some development of this system will be 
possible through the middle of next week while it moves westward 
across the eastern tropical Atlantic Ocean.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...20 percent.

4. An area of low pressure is expected to form near the southeastern 
Bahamas in a few days. Gradual development of this system is 
possible thereafter as it moves northwestward across the western 
Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...20 percent.

Forecaster Cangialosi

[H2O]

Two cherries and two lemons. Lots of tropical fruit 

[Weather Will]

WB 12Z Euro ensembles like the wave way out off the coast of Africa.

[WxUSAF]

D7-10 on the 18z GFS is incredibly entertaining. Fujiwara FTW

[toolsheds]

Heading to the beach next Fri-Sun.  :-)

[yoda]

00z Euro at the end of its run... hmmm... but looks like a recurve coming with that s/w in the Northern Plains?  Yes 10 days away and all too... it does look like there is decent ridging above though

[WxWatcher007]

5 hours ago, yoda said:

00z Euro at the end of its run... hmmm... but looks like a recurve coming with that s/w in the Northern Plains?  Yes 10 days away and all too... it does look like there is decent ridging above though

That looks like a recurve to me but like you said, 10 days away. If that weakness isn’t there that’s trouble. 

[WxWatcher007]

Nicholas adds to the count. 

Peak Season Forecast (Actual)
Named Storms:  13 (6)
Hurricanes: 9 (3) 
Major Hurricanes: 5 (2) 

[WxWatcher007]

Tropical Storm Odette coming at 5pm. System right off the Mid-Atlantic coast currently. Headed out to sea.

[yoda]

3 minutes ago, WxWatcher007 said:

Tropical Storm Odette coming at 5pm. System right off the Mid-Atlantic coast currently. Headed out to sea.

Into NF most likely

[WxWatcher007]

54 minutes ago, yoda said:

Into NF most likely

If it ain’t coming up the Bay, it’s OTS lol

[WxWatcher007]

On 9/14/2021 at 12:46 AM, WxWatcher007 said:

Nicholas adds to the count. 

Peak Season Forecast (Actual)
Named Storms:  13 (6)
Hurricanes: 9 (3) 
Major Hurricanes: 5 (2) 

Odette has arrived and Peter doesn’t look too far behind. 

Peak Season Forecast (Actual)
Named Storms:  13 (7)
Hurricanes: 9 (3) 
Major Hurricanes: 5 (2) 

[MN Transplant]

6 hours ago, WxWatcher007 said:

Odette has arrived and Peter doesn’t look too far behind. 

Peak Season Forecast (Actual)
Named Storms:  13 (7)
Hurricanes: 9 (3) 
Major Hurricanes: 5 (2) 

Ok, there are too many pages.  What are these numbers?  Is that a full-year forecast, or a forecast-to-date?  What does the () refer to?

[George BM]

41 minutes ago, MN Transplant said:

Ok, there are too many pages.  What are these numbers?  Is that a full-year forecast, or a forecast-to-date?  What does the () refer to?

13-9-5 is his peak season S/H/MH predictions (August 20th- October 20th). The numbers 7-3-2 in () to the right are the number of S/H/MHs so far during the August 20th to October 20th period.

[WxWatcher007]

3 minutes ago, George BM said:

13-9-5 is his peak season S/H/MH predictions (August 20th- October 20th). The numbers 7-3-2 in () to the right are the number of S/H/MHs so far during the August 20th to October 20th period.

This. Thanks. 

I update for each storm during that Aug 20-Oct 20 period once they’ve reached their peak intensity.

My forecast looks decent so far but there’s been more MDR slop than I expected. It’s really tough sledding out there.

There’s no real basin update right now, other than it looks harder to get any MDR system to get all the way west given how frequently troughs are showing up now. I think homebrew is going to be the best bet for US land impacts moving forward.

[MN Transplant]

8 hours ago, George BM said:

13-9-5 is his peak season S/H/MH predictions (August 20th- October 20th). The numbers 7-3-2 in () to the right are the number of S/H/MHs so far during the August 20th to October 20th period.

 

8 hours ago, WxWatcher007 said:

This. Thanks. 

I update for each storm during that Aug 20-Oct 20 period once they’ve reached their peak intensity.

My forecast looks decent so far but there’s been more MDR slop than I expected. It’s really tough sledding out there.

There’s no real basin update right now, other than it looks harder to get any MDR system to get all the way west given how frequently troughs are showing up now. I think homebrew is going to be the best bet for US land impacts moving forward.

Got it.  "Peak season" was throwing me off.

[PrinceFrederickWx]

On 6/2/2021 at 1:55 PM, PrinceFrederickWx said:

We're expecting another baby boy in early October, and just found out the name we had picked is actually on the hurricane names list this year. It's pretty far down the list so it's possible to be a hit here right around that time. 

 

Sam, first week of October. Get ready. 

[WxWatcher007]

 

[WxWatcher007]

I expected a somewhat active MDR, but like last season it’s been virtually all slop. Peter overperformed, but did not become a hurricane. Rose was low grade. 

98L is on the horizon with probably the best environment yet of the recent waves/systems and a much lower latitude.

Peak Season Forecast (Actual)
Named Storms:  13 (9)
Hurricanes: 9 (3) 
Major Hurricanes: 5 (2) 

[yoda]

00z Euro at 240 looked interesting 

[WxWatcher007]

6 hours ago, yoda said:

00z Euro at 240 looked interesting 

I think that one has a good shot to impact land, and the Antilles should definitely be watching. These low latitude lows generally have a much easier trek west. 

As for the US, still too far out..