Definition of tornado in question here.

[rdale]

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.

 

[Glenn Rivers]

Lake Ontario "waterspout"

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.

 

[rdale]

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.

 

[Robert Dewey]

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.

 

[Patrick Marsh]

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.

 

[Angie Norris]

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.

 

[rdale]

Angie: To avoid confusion - that would not have been a waterspout, it would have been a tornado over water.

 

[Scott Lincoln]

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.

 

[Greg Stumpf]

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

 

[rdale]

...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.

 

[scott r currens]

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.

 

[rdale]

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 ;>

 

[Robert Dewey]

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.

 

[Robert Dewey]

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.​

If we use that definition, a fair weather waterspout still isn't a tornado

 

[scott r currens]

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?