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May 13, 2008 Question: What is the difference between a hurricane, a cyclone, a typhoon and a tornado? Tornadoes have diameters on the scale of 100s of meters (1 meter = 39.37 Click here to cancel reply. Name (required)
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After tonight's spectacular waterspout roped out, I called the NWS Ruskin, FL to report the storm. It turns out that 40 people reported it. The funnel developed and touched down over Estero Bay and crossed over the island with the resorts and hotels. And there was definitely sand being lifted into the vortex, but the NWS will not call it a tornado due to the lack of damage and the only ground truth was the rapidly rotating sand cloud underneath the funnel cloud. Dewpoints had mixed out heavily today and it was about 95/60 at the time of touchdown. The condensation funnel didn't become whole until it was over the water due to the high dewpoint depression in the area. That's not important, just interesting. The question is: with ground truth of a debris cloud over land, it is by definition, a tornado, right? NWS Ruskin, FL doesn't seem to think so.
Correct, because waterspouts come on cool days. So that is not related to this particular discussion -- if it's connected to a supercell and/or lightning, it's not a Great Lakes waterspout.
That was a tornado by any definition used in the meteorological world.
Huh? Waterspouts from non-convective clouds? Explain.
Joking?
Waterspouts by their definition form under basically fair-weather cumulous and although I guess its technically still convection, waterspouts and tornadoes are very different. It peeves me to hear meteorologists call tornadoes moving over water 'waterspouts' when they are very different than waterspouts, and should be referred to as 'tornadoes over water' IMO.
Most of the time I here the term "cold air funnel" it is being used to describe a funnel/tornado from a small (mini and/or low-topped) supercell. Is this what you a talking about or something else? I guess I just don't know what a cold air funnel is.
A cold-air funnel is CLEARLY not from a supercell of any variety... It's from a light shower at most, usually just a few sprinkles on a fall day with a very cold-core low and usually northwest flow.
Thanks for the info Greg - I wasn't aware. I can't recall ever dealing with precip during a Toledo area waterspout, and no way was there ever any lightning.
I think that in this case, the NWS in Ruskin, FL, are going by what the funnel was in contact with, blast, before disspiating, which in this case was water, and so, in that sense, it wwould be called in as a Waterspout, but at the same time, it should've been noted, that it started off as a tornado and so, the finial cassiciation should have been TORNADO - WATERSPOUT, TORRO here in the UK, classifies waterspouts that make landfall or vice verse, in this same manner, and to me, it makes more sense to do so in this way :)
Willie
By the definition on Chuck's essay (not Chuck's definition, though), a gustnado is actually a tornado... It's violently rotating, and it's under a cumuliform cloud. I guess a dust devil that also occurs with a puffy cloud over head is a tornado as well.
By CADIII's definition, the vortex has to be embedded into and driven by the deep moist convection's bouyant processes.
A pure gustnado is not embedded in the convection, and is caused by mechanical forces along the shear zone at the leading edge of a gust front. These gust fronts can move very far away from the parent convection, but still cause gustnadoes.
A dust devil is driven primarily by dry convective processes.
But, there are hybrids. A gustnado could become stretched and ingested into an updraft. Even a dust devil, under unusual circumstances, could find itself under a developing updraft.
Thus, I must quibble with the standard definition for its exclusion of convective vortices that happen with clouds not meeting the criteria to be cumulonimbi (e.g., those without glaciation at the cloud top). I am proposing the following definition:Tornado -- A vortex extending upward from the surface at least as far as cloud base (with that cloud base associated with deep moist convection), that is intense enough at the surface to do damage should be considered a tornado.
Types of Tornadoes - <center></center>::
Mar 10, 2005 that are not connected to the cloud base, and by definition are not tornadoes. Get your questions answered here! WBKO Hometown Hero
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Dumbest question ever, page 1::
16 posts - 9 authors - Last post: May 9, 2005By the way, here is a link to the book: The $5 Billion It appears to be a question of definition. By your definition of a strategic bomber, or at least the one you used, the Tornado GR.4 would qualify as a
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If we use that definition, a fair weather waterspout still isn't a tornado :)
Tornado -- 1. A violently rotating column of air, in contact with the ground, either pendant from a cumuliform cloud or underneath a cumuliform cloud, and often (but not always) visible as a funnel cloud.That definition would mean any funnel connecting with the ground, beneath a cumuliform cloud, would be classified as a tornado. That would probably include the puffy innocent cumulus clouds that contain a brief spout...
I'd like to think of a TOR as coming from a Cb mesocyclone, versus pure temperature variation beneath a innocent puffy cumulus.
Unfortunately I can't find the source, but I remember reading a description of a "huge waterspout" over Lake Ontario sometime back in the late 1800's.
The description indicated that this so called "waterspout" occurring during a September night, in relatively warm weather, and was accompanied by frequent intense lightning and large hail. The "waterspout" came ashore in NY, and continued across land for many miles and did major damage. I feel pretty sure that this particular event must have been a supercell tornado that first touched down over the Lake.
Well, not all waterspouts. Just the ones from convective clouds, Lake Erie spouts are not tornadoes.
Do we consider dust devils to be tornadoes? Dust devils are closer to the thermodynamics of a fair weather waterspout than a mesocyclone-induced tornado.
...but in the end, just like our discussion in the OUN Survey thread, DOES IT MATTER? No. Doesn't matter in the slightest. If you are a researcher doing a survey of Michigan tornadoes, and found that 2 of the recorded tornadoes last year were from landfalling waterspouts - you would not go back into the archives and pull the radar data from that. If you want Florida waterspouts, you know how to differentiate them from Florida supercell tornadoes.
I will never go wall-to-wall for a waterspout over Lake Erie, regardless of Chuck's essay. The public does not consider them a tornado, but if you want to -- go right ahead. Once you've actually seen one, you'll know why.
If we use that definition, a fair weather waterspout still isn't a tornado :)
Based on which part, deep moist convection or strong enough to do damage? Ask Greg :: WRAL.com::
A drawback here is the need for uninterrupted power and internet services. Question: Thanks for your recent definition of "dew point," but what is its Question: Is there a place I can see historical tornado tracks for our area?
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TORNADO SAFETY::
Although waterspouts are always tornadoes by definition; The Storm Prediction Center issues tornado and severe thunderstorm watches; here is an example. . Excellent question -- and a very, very disturbing one to many
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Not only that, but there are many tornado LSRs on record that are described as landfalling waterspouts.
Doing a quick search reveals myriad LSRs where landfalling waterspouts were recorded as tornadoes. The most recent I can find was June 18, 2007 at Miami Beach, FL.
MIAMI BEACH FL (9 E MIA) 18/0720 WATERSPOUT MOVED ONSHORE MIAMI BEACH NEAR 10TH STREET
And another on June 1:
2 NE SUGARLOAF KEY FL (16 ENE EYW) 1/1112
WATERSPOUT MOVED ONSHORE SUGARLOAF KEY
By the definition on Chuck's essay (not Chuck's definition, though), a gustnado is actually a tornado... It's violently rotating, and it's under a cumuliform cloud. I guess a dust devil that also occurs with a puffy cloud over head is a tornado as well.
Interesting.
The same thermodynamics (sustained updraft) and a convergence zone over land can result in the same non-supercell tornado process.
I passed over that the first time... If that were the case, then is it just a coincidence that days with waterspouts never have anything even closely related to that over land? Often there aren't even any clouds over land. The water temp is the sole cause of the updraft. Tornado Chase 2000May 4, 2000 - 7:00 p.m. ETWhere do tornadoes ::
The Tornado Team: Basically, the short answer to this question is: No, . The definition of a tornado is "a violently rotating column of air in . Fort Worth, TX: Recently, a tornado devestated some high rise office buildings here.
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LOL, that is pretty funny. Word has it Greg has see a waterspout or two.;) But most of them were on Lake Ontario so I am sure they were nothing like the ones you see. I think he even has a picture of one during a LES event.
Yep - 4 years at SUNY Oswego will do that to you. Now that I finally have a photo scanner at home, I should post that winter-time spout pic.
I've also seen Florida Keys spouts. BTW - be aware that photogrammetry studies of H20spouts have founds winds of up to 140 mph! I wouldn't call that "fair weather".
I guess there's no point in arguing semantics... My personal opinion is that if the same funnel wouldn't have developed over land simply because of the absents of water, then I would consider that a waterspout. In other words, if water at the surface is the motivating factor in the development and sustenance of the funnel, I consider that a waterspout.
But the same process that produces a waterspout also produces a landspout. It has nothing to do with the underlying surface. Where there are waterspouts, the water provides a source of instability. Where there are landspouts, the land provides a source of instability.
Where there are supercell tornadoes, the earth's surface provides instability (could be either land or water). So by the same argument, these should be called different things, which they are not.
We are confident that the process which produces supercell tornadoes and non-supercell tornadoes of the "stretching a vortex on a pre-existing boundary" kind are different, but why call the latter different things based on the surface the vortex is connected to?
They are all tornadoes.
I'm no landspout expert - but aren't they connected with some sort of precip? GL waterspouts are dry.
Only in that the convective process that under the right circumstnces produces a non-mesocyclone tornado, may or may not be producing precipitation concurrently in and near the same updraft.
Dan Chaffee
Both, but primarily deep moist convection.
As for the 140 MPH claim, that's pretty interesting. Was this in fact a "fair weather waterspout" or was it associated with a thunderstorm and/or mesocyclone? I guess I can imaging a fair weather waterspout getting that strong, just as I've seen some pretty "violent" dust devils that are also "fair weather" occurences.
Can you locate for us a definition of a "fair weather waterspout"?
Every waterspout that I've observed has been connected to deep moist convection.
I'm no landspout expert - but aren't they connected with some sort of precip? GL waterspouts are dry.
If you push the envelope too far - we'll classify the rare cold air funnel touchdown as a tornado too...
This was a non-supercell tornado/waterspout I witnessed. The funnel dropped from the forward flank of a thunderstorm that was severe-warned for 65mph straight-line winds. It likely developed along a pseudo mini-"triple-point" that developed from the convergence of a southbound OFB, a northbound OFB and the eastbound sea-breeze. This convergence was evident on the KTBW radar shortly before the event. I've never heard of a "fair-weather" waterspout. I have heard of fair weather whirlwinds (water-devils) that can occur over water as well as over land which are NOT pendant from a cumuliform cloud.
About the 6/25 event:
1. This was pendant from a cumuliform cloud with severe weather occuring and numerous CG lightning strikes.
2. A ground circulation was evident on the barrier island as the vortex tracked from Estero Bay over to the GoM. Waterspout, to landspout then back to waterspout again.
With that, it seems that this would be without question, a tornado.
GL waterspouts are dry.
Perhaps you found the difference between Erie and Ontario spouts! :D
All of the spouts I witnessed on Lake Ontario were in association with deep moist convection (electrified and not electrified), with rain/snow, and certainly not "dry".
It's unfortunate that all waterspouts are not recorded by the NWS as tornadoes, because this is what they are.
Can you locate for us a definition of a "fair weather waterspout"?
Every waterspout that I've observed has been connected to deep moist convection.
NWS: http://www.srh.noaa.gov/mfl/hazards/info/waterspouts.php
Fair weather waterspouts usually form along dark flat bases of a line of developing cumulus clouds. This type of waterspout is generally not associated with thunderstorms whereas tornadic waterspouts develop in severe thunderstorms.
Can you locate for us a definition of a "fair weather waterspout"?
Nevermind, I just found one here (http://www.srh.noaa.gov/mfl/hazards/info/waterspouts.php):
"Fair Weather waterspouts are usually a less dangerous phenomena, but common over South Florida’s coastal waters from late spring to early fall. The term fair weather comes from the fact that this type of waterspout forms during fair and relatively calm weather, often during the early to mid morning and sometimes during the late afternoon. Fair weather waterspouts usually form along dark flat bases of a line of developing cumulus clouds. This type of waterspout is generally not associated with thunderstorms whereas tornadic waterspouts develop in severe thunderstorms. Tornadic waterspouts develop downward in a thunderstorm while a fair weather waterspout begins to develop on the surface of the water and works its way upward. By the time the funnel is visible, a fair weather waterspout is near maturity."
And it is partially incorrect and misleading.
"dark flat bases of a line of developing cumulus clouds" - no, a developing line of cumulonumbis clouds (towering Cu), which is deep moist convection.
"generally not associated with thunderstorms" - deep moist convection does not require lightning. In fact, some tornadic supercells associated with landfalling tropical systems don't contain lightning.
"Tornadic waterspouts develop downward" - uhhhh....no.
I don't think there's much question, Robert, that "cold-air" vorticies are tornados if they otherwise meet the tests, i.e. severe-level circulation at ground-level and driven by cloud-level convection. The western states get a pretty good share of these.
Great Lakes waterspouts should not be considered tornadoes.
Why should the name of a particular section of the earth’s surface have anything to do with what we classify a tornado?
Well, not all waterspouts. Just the ones from convective clouds, Lake Erie spouts are not tornadoes.
Huh? Waterspouts from non-convective clouds? Explain.
Joking?
Great Lakes waterspouts should not be considered tornadoes.
Based on which part, deep moist convection or strong enough to do damage?
Both, but primarily deep moist convection.
As for the 140 MPH claim, that's pretty interesting. Was this in fact a "fair weather waterspout" or was it associated with a thunderstorm and/or mesocyclone? I guess I can imaging a fair weather waterspout getting that strong, just as I've seen some pretty "violent" dust devils that are also "fair weather" occurences.
I'm no landspout expert - but aren't they connected with some sort of precip? GL waterspouts are dry.
If you push the envelope too far - we'll classify the rare cold air funnel touchdown as a tornado too...
Many of the tornado warnings (for landspouts) you get in eastern Colorado occur when there is no precip on radar. Like waterspouts they are most common in a cooler post-frontal environment. I seem to have zero ability forecast them so I have givenup on targeting that kind of setup. The non-mesocyclone tornadoes I have observed most often occured on the flanking line of a supercell but not in association with the meso.
Most of the time I here the term "cold air funnel" it is being used to describe a funnel/tornado from a small (mini and/or low-topped) supercell. Is this what you a talking about or something else? I guess I just don't know what a cold air funnel is.
Thanks guys, I knew that all along. But NWS Ruskin, FL is not going to call it one at this time.
Unfortunately I can't find the source, but I remember reading a description of a "huge waterspout" over Lake Ontario sometime back in the late 1800's.
The description indicated that this so called "waterspout" occurring during a September night, in relatively warm weather, and was accompanied by frequent intense lightning and large hail. The "waterspout" came ashore in NY, and continued across land for many miles and did major damage. I feel pretty sure that this particular event must have been a supercell tornado that first touched down over the Lake.
Possibly September 26, 1898...page 685 Significant Tornadoes has a family of tornadoes from St. Catherines, Ontario to Alden, New York that crossed the Niagara River from Ontario into New York. Doesn't specifically mention a waterspout, but if it crossed a body of water, would have briefly been a waterspout.
Once you've actually seen one, you'll know why.
LOL, that is pretty funny. Word has it Greg has see a waterspout or two.;) But most of them were on Lake Ontario so I am sure they were nothing like the ones you see. I think he even has a picture of one during a LES event.
Why should the name of a particular section of the earth’s surface have anything to do with what we classify a tornado?
Probably for the same reason that snow coming off of a lake is classified as LES. Sure it's still snow, but the process is entirely different.
Most waterspouts on the Great Lakes occur in the late fall, when the temperatures are in the 40's or 50's, with strong delta-T's over the lake. Hell, you can navigate a boat right through most of them without much more than a puff of wind and some spray... it's not a tornado in the classic sense.
In my book, tornadoes come from a mesocyclone process... anything else (over land) is a spin-up and a result of the terrain.
All Great Lakes waterspouts are similar. Erie gets the most as I recall, Superior the least. Can't remember the guys name from Environment Canada, but he speaks at the GLOM workshop every year and has the most impressive collection of pictures in existance, and even developed a flow chart to aid in the forecasting of waterspouts.
And not to give it all away - but CAPE doesn't need to be more than 1000 ;>
No. I use terms that the viewers understand and not wanting them to think it's the same thing as a tornado. When compiling the list of tornadoes at the end of the year - I would not want it in the database.
I call it a waterspout that moved onshore and caused some damage.
Angie: To avoid confusion - that would not have been a waterspout, it would have been a tornado over water.
I guess there's no point in arguing semantics... My personal opinion is that if the same funnel wouldn't have developed over land simply because of the absents of water, then I would consider that a waterspout. In other words, if water at the surface is the motivating factor in the development and sustenance of the funnel, I consider that a waterspout.
If we have a tornadic thunderstorm that is capable of producing a funnel regardless of terrain (water, vegetation, dust, etc), then I consider that a tornado.
That's my personal thought, as I can't keep up with a semantic argument. ;)
Waterspouts by their definition form under basically fair-weather cumulous and although I guess its technically still convection, waterspouts and tornadoes are very different. It peeves me to hear meteorologists call tornadoes moving over water 'waterspouts' when they are very different than waterspouts, and should be referred to as 'tornadoes over water' IMO.
I guess it is time to once again share this:
http://www.cimms.ou.edu/~doswell/a_tornado/atornado.html
Take away the water, and there's no waterspout (or tornado as you refer to.) Put the exact same environment over land (which happens) and there's no waterspout or tornado.
I disagree. The same thermodynamics (sustained updraft) and a convergence zone over land can result in the same non-supercell tornado process.
So, what do you call a Great Lakes vortex that moves on shore and causes damage? Is that not a tornado?
Hell, you can navigate a boat right through most of them without much more than a puff of wind and some spray... it's not a tornado in the classic sense.
I know of at least one occasion where F15s (or F16s can't remember exactly which) from McDill Air Force Base near Tampa have flown threw waterspouts down there as well.
If you aren't going to classify Great Lake waterspouts as tornadoes, then you can't classify Florida waterspouts as tornadoes either. However, I would aruge that they both should be counted as a tornado. Do people count landspouts as tornadoes? IF so, a waterspout is formed by very similar process (vorticity stretching) and should also be counted.
Just my opinion.
Scott - it's not the name of the particular section of Earth underneath. It's because the waterspout is caused BY the particular section of Earth underneath. Take away the water, and there's no waterspout (or tornado as you refer to.) Put the exact same environment over land (which happens) and there's no waterspout or tornado.
I realize you've never seen one to be able to tell the difference - but you can hunt down some video and/or stop up here in the fall and you'll KNOW there is a difference between a Lake Erie waterspout and a tornado.
Sometimes the formal definition can be modified by common sense.
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Definition of tornado in question here.