I haven't been biking very long but there's a piece of gear that I have that is valuable with two of my long time hobbies (very long range competition shooting and flying) that may be of significant use in biking. That would be a Kestral 4000 weather tracker. It will measure altitude, wind speed, humidity, barometric pressure, density altitude, dew point, wind chill, heat index and several other even more esoteric things. More importantly it will take and store the data at intervals and either show the raw data or graph it. It's about the size of a pre-flip cell phone, weighs a couple of oz and cost around $250. For all the altitude/density data, you'll need to do an initial calibration on it from a point of known altitude or barometric pressure.

I know it's not needed by everyone but there may be someone who will benefit. I turned it on this am and got freaked out since the heat index was 112 F at 10:30 AM here in Florida. Lord, give me a break.

Interesting - I can see why sailors/windsurfers/climbers would like it. But I think for cycling we mainly need to know the forecast before we set out on a ride.

I like "Weatherbug" ; it's free; runs on my cellphone. Only problem is you have to run it before you get out of cellphone range if you're on a long ride.

Dude, I hear what you are saying. I'm a victim of cheap cell phone Internet web pages. I use the "radar" function on my itty-bitty screen to try and figure my chances of making it through a thundershower.

I doubt you gizmo would give me much useful info, but i wish i could have a few more square inched of screen for radar weather maps.