ATL: CRISTOBAL - Post-Tropical - Discussion

[Stormcenter]

But didn’t the NHC themselves state that was
a real possibility earlier in the week?

Sat pic with obs. Circulation fairly weak over the Yucatan. Pressure fairly high in the squalls near the northern Yucatan. I'm not sure how long the weak LLC inland will survive. For the past week, models have predicted the center to move inland yesterday then possibly dissipate inland, followed by a new low forming near the NW Yucatan on Friday. Won't change the eventual impact much. Note that on the NHC track you shouldn't draw a straight line between the 72 hrs and 84 hrs track points (across Morgan City or east Vermilion Bay). The center may get almost to the coast before it jogs NW. Good news is that there may not be any real strong wind near the center (no core). TS winds may reach all the way to the AL coast Sunday.

http://wxman57.com/images/Cristobal1.JPG

I think you could make the argument that models are showing a second storm developing and the storm that hits the Gulf Coast could actually be Dolly.

That's what I was arguing early this week. Cristobal dies over MX and Dolly forms by NW Yucatan. Thought it would be simpler to follow the NHC's lead and indicate only 1 storm. I don't think there's any way the NHC will declare Cristobal dissipated and begin advisories on Dolly, even though, technically, that might be more correct.

[Aric Dunn]

I’m seeing a lot more “chatter” on the interwebs about the possibility of Cristobal’s core dissipating and a new low, possilbility “Dolly” forming in the Gulf of Honduras.

Yeah the possibilty is being discussed...

[psyclone]

Right and weak usually cashes a ticket in the early season. Cristobal had a good chance to buck that trend until it departed the sea.

[Craters]

Sat pic with obs. Circulation fairly weak over the Yucatan. Pressure fairly high in the squalls near the northern Yucatan. I'm not sure how long the weak LLC inland will survive. For the past week, models have predicted the center to move inland yesterday then possibly dissipate inland, followed by a new low forming near the NW Yucatan on Friday. Won't change the eventual impact much. Note that on the NHC track you shouldn't draw a straight line between the 72 hrs and 84 hrs track points (across Morgan City or east Vermilion Bay). The center may get almost to the coast before it jogs NW. Good news is that there may not be any real strong wind near the center (no core). TS winds may reach all the way to the AL coast Sunday.

http://wxman57.com/images/Cristobal1.JPG

I think you could make the argument that models are showing a second storm developing and the storm that hits the Gulf Coast could actually be Dolly.

That's what I was arguing early this week. Cristobal dies over MX and Dolly forms by NW Yucatan. Thought it would be simpler to follow the NHC's lead and indicate only 1 storm. I don't think there's any way the NHC will declare Cristobal dissipated and begin advisories on Dolly, even though, technically, that might be more correct.

Would it be more correct, though, Wxman? If, after all of this, a different low formed from some outer region of convection that was obviously part of TS Cristobal, it would still be part of the system whose name until recently was Ni -- I mean Cristobal. Would it be all that different from a storm moving across, say, Hispaniola and having its LLC reform in a different location as a result? I mean, granted that the distance between the two lows could be larger in the hypotheticcal Cristobal scenario than it would in the imaginary Hispaniola case, but it seems that the general idea would be the same.

Of course, it's obvious that I'm far from comfortable with the nuances of storm-naming, and this is admittedly getting down in the weeds...

[wxman57]

But didn’t the NHC themselves state that was
a real possibility earlier in the week?

I think you could make the argument that models are showing a second storm developing and the storm that hits the Gulf Coast could actually be Dolly.

That's what I was arguing early this week. Cristobal dies over MX and Dolly forms by NW Yucatan. Thought it would be simpler to follow the NHC's lead and indicate only 1 storm. I don't think there's any way the NHC will declare Cristobal dissipated and begin advisories on Dolly, even though, technically, that might be more correct.

Yeah, the NHC saw the same thing, but it would be quite confusing to split it into two storms. I agree.

[Stormcenter]

Something definitely happening off NW Yucatán not sure
what though.

[Aric Dunn]

Something definitely happening off NW Yucatán not sure
what though.

sustained convection will inevitably start increasing vorticity. as the circ dies over land. watch anywhere from the NW carrib up through the southern gulf and to the NW Yucatan for something to try to organize..

[wxman57]

Something definitely happening off NW Yucatán not sure
what though.

Trof extends from Cristobal up central Yucatan to the squalls. Pressure up there about 1010mb.

[Steve]

Something definitely happening off NW Yucatán not sure
what though.

sustained convection will inevitably start increasing vorticity. as the circ dies over land. watch anywhere from the NW carrib up through the southern gulf and to the NW Yucatan for something to try to organize..

I agree though it's hard to say if that energy will be a circulation or will wrap into it near the northern tip of the Yucatan. Some of the depiction models have been indicating this for a while.

Anyway, I like the NHC's track at this point. What's different is the timing as the northward movement is pretty fast from the Yucatan to the LA Coast in a hair over 2 days. As I pointed out Tuesday night in the model discussion (CMC I think), there was a ridge pushing in off the Atlantic from the East and another one pushing into W TX forcing the squeeze play North. However, there is likely to be a ridge centered north of Cristobal as well which is why several of the models have shown a westward jog or slide close to the coast. That's standard clockwise flow and makes sense depending on that ridge's alignment.

[tailgater]

Something definitely happening off NW Yucatán not sure
what though.

Check out what the HWRF does with the convection on the NW tip of the Yucatán

[Hypercane_Kyle]

Looking increasingly likely Cristobal will dissipate over Central America.

[Craters]

Something definitely happening off NW Yucatán not sure
what though.

Could that convection be dry-line related? The low-and mid-WV channels are really showing a sharp WV boundary: e.g., https://weather.cod.edu/satrad/?parms=s ... =undefined

Sorry, can't post the image.

[bella_may]

https://twitter.com/ashleyruizwx/status ... 59845?s=21

Much needed rain on the way for some people

[wxman57]

Something definitely happening off NW Yucatán not sure
what though.

Check out what the HWRF does with the convection on the NW tip of the Yucatán

Let me get the latest HWRF run out of my trash can. It's not still taking the storm into the East Pac?

[wxman57]

Something definitely happening off NW Yucatán not sure
what though.

Could that convection be dry-line related? The low-and mid-WV channels are really showing a sharp WV boundary: e.g., https://weather.cod.edu/satrad/?parms=s ... =undefined

Sorry, can't post the image.

That's a good bit of yellow air out there in the Gulf. There is a trof axis extending NNE from Cristobal along the moisture boundary.

[GCANE]

OSCAT is showing 40 knt surface winds north of Cancun.

[MississippiWx]

As of now, the low level vort is still very much intact. For a new storm to develop, this one is going to have spin down a lot.

[wxman57]

OSCAT is showing 40 knt surface winds north of Cancun.

https://i.imgur.com/Y7SsNG5.jpg

Actual surface obs indicate 15-20 kts there. In fact, if you divide those wind speeds by 2 all across the map, then that would produce a map very close to current surface obs.

[chaser1]

OSCAT is showing 40 knt surface winds north of Cancun.

https://i.imgur.com/Y7SsNG5.jpg

I see that too. Looks to be essentially gradient related reflective of the higher pressures at that latitude. Same wind speeds extend well to the west. Now if those winds just north of Cancun were hinting of a directional change, that would get me attention

[Jonny]

Dolly cannot form yet.

I need a category 5 storm that we can nickname “Dolly Dearest” (movie reference). lol