With all the chat about snow levels on the AZT route I thought I’d offer some insights on how those snow models transfer to actual on-ground conditions. Click for the bigger version…
The red line was my planned route, the blue was as far as I was able to go due to conditions. Where I was forced to turn back (just E of the blue ball) the trail transitioned from south facing, dry trail to north facing, 2+ feet of snow trail. Exposure is everything. That was at an elevation of `5800.
If you’ve got a GPX track of your route, TopoFusion, and a web browser this is pretty easy to do for your own route:
1. Start here: www.nohrsc.nws.gov/ then select the interactive maps on the top left. Zoom into your region of interest.
2. Copy and save the image of your region of interest. Make sure you’ve got a couple of well spaced “anchor” points. I used Enterprise and New Harmony and it looked like this:
3. In TopoFusion, have your area of interest in view, then go to window->user map library. Add the image from step 2 above. You “calibrate” the image to the TF maps by a few different methods, my preferred is to do it manually, dragging the image handles until your anchor points from your image overlay the same points on the TF maps.
4. Click the hand top left in TF and now you’ve got a superimposed snow model over your GPX track. Pretty slick, eh? Hit the 3D button and you can get a good idea where the trouble spots will be. North facing = lingering snow.
Here’s one I’ll be watching closely the next couple of months!
Cool stuff, Dave. So even the light blue pixels are bad if north facing. Makes some sense.
Nice use of TF — I dig it. I usually use the click method to calibrate, but for something like this you are right that it’s not hard to get it lined up just by resizing.
So right now about 5% of the 311 is ready to go. Sweet.
Very nice – thanks for the knowledge! Just plugged in the Paradox and it looks like it’s on for the weekend! Tab? – yeah, that’s still purple…