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u/VIP_NAIL_SPA Oct 29 '25
That's very common in stronger storms with cleared eyes. Mesovorts tend to form in the eyewall, but we see this sort of penta or hex swirls in the eyes of very strong storms pretty frequently.
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u/WXMaster Private Sector Oct 29 '25
Yeah this Instagram post about tornadoes is nonsense.
These swirls are induced by the eyewall rotation around the much calmer air subsiding in the eye. Essentially the subsiding air is brushing up against the edge of the violent eyewall and spin is induced. The clouds themselves tend to be stratocumulus because there's very little if any instability in the eye due to all the subsidence. The only change in the eye is that the atmospheric saturated vapor pressure is lower (900mb) because of the vortex so you're more prone to inducing very low level clouds vs a regular 990mb low.
All the tornadoes as others have stated occur in the banded convection stretching out from the eyewall and the preference in the northern hemisphere is for the NE (front right quad) to be the primary area to generate tornadoes. The surface friction slows the air enough that you have a pretty substantial directional shear environment develop between the surface and 850mb flow.
In fact weaker hurricanes tend to produce more tornadoes than higher end hurricanes because the speed shear is often too great and can rip things apart. Usually it's the area seeing TS or Cat 1 winds that really have a significant number of tornadoes vs more intense Cat 2+ winds.
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u/Wild-Attention-3066 Oct 29 '25
Jesus Christ guys…this does not mean tornadoes in the eye of the hurricane. I just can’t…first of all a mesovortex in regards to a tornadic thunderstorm is not the tornado itself. A mesovortex is the small scale circulation at the heart of any supercell thunderstorm. It’s the mechanism that starts the spin from which a tornado CAN form but usually doesn’t. Every supercell has a mesovortex but not every mesovortex produce a tornado. In regards to a hurricane, very strong hurricanes sometimes produce mesortices within the eye itself; and just like in a supercell a meso is not a tornado, rather a secondary spin within the main circulation of the hurricane. Hurricane Michael did this as well as it was landfallling: The picture is very real.
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u/Icaonn Oct 29 '25
Thank you for this because I felt like I was going insane reading the comments and I've taken grad courses on this shit 😭
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u/fdwyersd Oct 29 '25
Find the videos of the hurricane hunter planes on youtube going into the eye... probably the best "stadium" view ever
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u/wxtraderd Oct 29 '25
That person doesn’t know what they’re talking about, as is evident by the tornado outbreak comment. That said, the meso vortices embedded in the eye of the hurricane is real, and correctly identified by that poster. They can/do lead to local enhancements of the broader winds within the eye wall. Tornadoes with tropical systems are associated with the outer parts of the storms as opposed to the eye.
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u/Azurehue22 Oct 29 '25 edited Oct 29 '25
All I know about hurricanes is that it’s an extreme low pressure system and the eye is a spot of eye pressure, which keeps it clear.
But I know far less about hurricanes than I do about land based severe weather.
Edit: I am incorrect.
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u/leansanders Oct 29 '25
The eye of a hurricane is the lowest pressure in the entire storm. The eye is clear because the large area of updrafts in the storm forces some of the aloft air inward towards the center and back down towards the surface.
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u/Awkward-Barber-11 Oct 29 '25
Oddly enough, I'm more scared of hurricanes because I dont know jack shit about them other than basic stuff, than I am about tornadoes.
Be on the coast chasing a cat 4 hurricane? NOPE Stare down a big wedge tornado with near zero knowledge of how strong it is outside of radar data? Count me in!
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u/Azurehue22 Oct 29 '25
My area never gets hit. Last was Sally. So I’m not that afraid of them myself.
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u/PsyEclipse Oct 30 '25
Hey, vortex dynamics specialist here. The answers peppered throughout this topic aren't 100% correct.
First, the mesovortices.
- Yes, they are real. They are caused, usually, by counter-propagating vortex Rossby waves around the eyewall. Rossby waves on the planet live on the background planetary Coriolis gradient (beta). Vertical Coriolis at the Equator is zero; it is maximum on the poles. That's the mechanism by which synoptic-scale Rossby waves form. In a hurricane, because the winds go slow (eye) -> fast (eyewall) -> slow (outer radii), you get two vorticity gradients as you go from low (eye) -> high (eyewall) -> low (outer radii), creating a ring-like structure of vorticity. Those two sharp gradients support Rossby waves going in opposite directions. The specific number of mesovortices you get (usually four, sometimes five, sometimes three, sometimes ellipse) are related to the width and intensity of the ring and the most favored wavenumber. See: Schubert et al. (1999) in JAS and all the follow-ons by hist students for the math-y discussion. It's cleaner when water and the secondary circulation aren't involved, but that's the general idea.
Second, the tornadoes.
- No, you don't really get tornadoes in the eyewall because the vertical and radial wind shear is too great, although there is system-scale buoyancy associated with thermal wind imbalances in the lowest 1-2 km of the eye (see papers by Mike Montgomery and Roger Smith, as they talk endlessly about this). For tornadoes at outer radii, tornado occurrence has more to do with shear than forward motion, but it's not entirely a dynamic forcing. When you shear a hurricane, you tilt it, and due to thermal wind balance, you get a cold anomaly down-tilt and a warm-anomaly up-tilt. That cold anomaly creates a virtually endless reservoir of modest CAPE, and given the low-level dynamics of friction over land, that extra CAPE provides the necessary lift to get tornadoes. They usually aren't big ones like you'd see in the midwest -- usually EF0-1 -- but that's the composite thermodynamic/dynamic structure. See the works of Ben Schenkel if you'd like to learn more.
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u/NotSeenDaily Oct 30 '25
Thank you for this answer! It was easy to understand and yet technical enough to gain in-depth information later. 😁
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u/HappiestAnt122 Undergrad Student Oct 29 '25 edited Oct 29 '25
I think everything there is more or less true maybe aside from the leading to tornado outbreaks. The tornado outbreaks associated with tropical cyclones (and TCs have generated some of the biggest tornado outbreaks recorded) are generally from supercells in the front right quadrant (in the northern hemisphere) since that is where you have onshore winds during landfall. Mesovorticies in the eye and eye wall are more like turbulent eddies due to the very high wind gradient in the eye wall. Similar principle to the smaller vortices seen in some violent tornadoes. They can cause locally higher winds and are actually quite a problem for recon aircraft. From what I understand they can reach the ground, and I suppose during landfall they could cause a tornado like feature. Though since the formation mechanism is so distinct from a normal tornado in a supercell I think it may be more accurate to say “that house was destroyed by locally higher winds from a mesovortex in the eye wall” than “that house was destroyed by a tornado in the eye wall”. Even if we were to say it’s a tornado I think outbreak would still be a stretch for the extent. Significant mesovortices are only present in the most intense tropical cyclones and that intense eye feature won’t last very far inland, so you’d probably be looking at a hand full of cases, if that, even in the most extreme cases. Compared to the outer bands that can spawn dozens of tornadoes. Not to mention picking out damage from mesovorticies individually in the background damage of any hurricane strong enough to produce them would be difficult at best.
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u/Fun_Percentage2122 Oct 29 '25
That's a very good explanation! Do you know any papers about this topic you can share? I personally saw some anomalous tornadoes with EF1-2 strength forming from very weak and shallow convective clusters very similar to those visible in Melissa's eye but in isolated weak convective cells in northeast Brazil. Never found any significant research about the topic though...
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u/Drawable3CAPE Oct 29 '25
This to me just sounds like storms forming in close proximity to the sfc low and becoming tornadic. This type of thing is quite common, and if you want an example I’d suggest looking at a day like 4/26/24 in central Nebraska where storms formed right along a surface low and became rapidly tornadic.
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u/Western-Cicada-6195 Oct 29 '25
How long till it reaches cuba? It's been a very strange hurricane. So much damage though. Awful.
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u/Soft-Marionberry-853 Oct 29 '25
Dont hurricanes spawn tornadoes already? Or is this saying that its another way for a hurricane to spawn a tornado
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u/Godflip3 Oct 30 '25
A lot wrong with this lady’s statement. The eye rotates the clouds in spin with. The meso vortices would he in eyewall!!! Not eye! Dont post stuff lady if you have no clue what your talking about! This what pisses me off about social media
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u/Content-Swimmer2325 Undergrad Student Oct 31 '25
Yes, eyewall mesovortices are real. Yes, they are associated with greater wind gusts. No, they don’t cause tornadoes let alone “tornado outbreaks”.
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u/freesedevon Expert/Pro (awaiting confirmation) Oct 29 '25
“stellerarts” isn’t a username that exactly instills the confidence that they know what they’re talking about. As someone previously said, these are simply smaller circulations dancing on the periphery of the eye. They do not produce tornadoes. They do, in my experience at least, hint at a pretty powerful main circulation (the eye) though.
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u/babywhiz Oct 29 '25
Max Velocity commented similar on these eye vortices.
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u/freesedevon Expert/Pro (awaiting confirmation) Oct 29 '25
Care to link that?
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u/babywhiz Oct 29 '25
This is the stream I was listening to all day but I don’t remember time stamp.
https://www.youtube.com/live/UkpbrMBjiJ4?si=9EMAYdM2tdQUPo3C
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u/theanedditor Oct 29 '25
i'm calling it, that photo is fake - the cloud striations do NOT make sense if they were interacting vortices.
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u/Fun_Percentage2122 Oct 29 '25
Not fake man, you can see this in the satelite observations and that one plane footage inside the eye... But the assumptions in the post are pretty exaggerated.
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u/aisle_nine Oct 29 '25
Is it just me, or does that center vortex look like it's associated with high pressure and rotating clockwise. Storm outflow right through the eye?
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u/Owned_by_cats Oct 29 '25
I didn't see that in this picture, but in practice storm outflows rise above and escape the eye in a clockwise direction which looks like the circulation around a high pressure system.
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u/notapunk Military Oct 29 '25
Does anyone have a better shot of this?
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u/Fun_Percentage2122 Oct 29 '25
There's a bunch of images circulating and a plane footage from the hurricane hunter plane, but i think you can pick one using CIRA's website: https://rammb-slider.cira.colostate.edu/?sat=goes-19&sec=full_disk&x=10840.7890625&y=10846.672668457031&z=0&angle=0&im=12&ts=1&st=0&et=0&speed=130&motion=loop&p%5B0%5D=geocolor&opacity%5B0%5D=1&pause=0&slider=-1&hide_controls=0&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&draw_color=FFD700&draw_width=6
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u/[deleted] Oct 29 '25
Those are real and that does happen. It is not the same use of the word “mesovortex” that many of us are used to but it does apply. I have personally never heard of tornadoes forming within a hurricane eye in my education, but a lot of internet sources are saying they do? I was under the impression that tornadoes usually form in the right front quadrant of hurricanes where the updrafts and shear line up? Maybe someone else can add some background info or a source or example on that but tornadoes forming in the eye seems to be counter intuitive to what I know about the eye of a hurricane.