How to make a simple spiral w/ arrow like the Weatherman I'm making a YouTube video about a tornado in a campfire I videorecorded. I want to show my viewers the mechanics of the tornado. 

Here's a screen shot of what I'm after:


I'm not looking to be a Blender expert (although it looks like a neat program to learn.) I just want to render a 2 turn spiral that I can rotate. 

I tried making a spiral from the add curves. I made it taper as it got higher. I extruded the curve in the Z direction and hacked my way thru disconnecting a segment and connecting two, to complete a mesh. It's exactly what I want, but Blender doesn't see it as a solid. (No faces.)

When I made a "flat" spiral (that is, no taper in Z), I can extrude it in Properties and Blender sees that as a solid. But I can't figure out how to taper it in Z after the fact.
None of the suggestions already on StackExchange specifically addressed what I wanted to do. Here's what I finally came up with:

my weatherman-type rendered spiral http://s1.postimg.org/hewpl3ym5/rendered_spiral.jpg

I created a spiral; in Geometry, I used a custom bevel and taper. I assigned it a material. I used hemi light in Blender Render. (So no shadow where one part of the ribbon crosses the other.) I added a 3 point mesh triangle for the arrow and made that a child of the spiral so that it would rotate with the spiral during animation. I added a black border in BR post processing. (Whew! Took 3 days with lots of reading and watching youtube tutorials.)