Weather HD is one of those applications that you want on your iPhone, iPad or touch purely for the high-def eye candy, and it's too bad you can't use this app in place of your lock or home screen. The forecasts come from weatherunderground.com, and the app dooesn't do much more than tell you current and forecast weather--no fancy maps, satellite or radar views--but the sky condition animations that accompany the reports are downright cool.
When you first install the app (get it here on the app store), you have to specify a location to monitor, and it asks to use your current location automatically. At first I waited at a black screen for several minutes (without anything happening), so finally killed the app and restarted it again. The second time, I went back in and configured it manually (making sure my network connection was stable) and finally the display came up, so not sure if some error-checking routine in the program fell short, or it was just a glitch on my 4G touch (running 4.1 version). The app is pretty large at 155MB, so you might want to wait until you get a wifi connection to grab this one. It should work on iPhone, iPod touch and iPad running OS version 3.2 and up.
The main screen indicates pretty standard current conditions information for your locale along the bottom of the display. The sky condition, visibility, temperature, humidity and pressure, etc. A nice touch would be to add some kind of trend indicator. One thing weather geeks love--having been one myself, I should know--is to be able to quickly tell how the weather is trending, especially pressure, temperature and humidity. You can turn on/off a few features in the settings, and set your unit of measure for temp. The application also has a "night viewing" mode that can be enabled. A double-tap when the app is running dims the screen.
You can quickly swipe back and forth along the top to change between different cities. The time can be turned on/off or enlarged in the settings, and you can quickly view forecast information by tapping the forecast selector at the bottom. You can also drill into hourly or daily forecast information.
As I said from the outset, the coolest thing about this app really isn't the weather aspect, but the weather animations that accompany each station condition. Setting up a bunch of stations all over the world (in different timezones) will gurantee you get a good mix of animated scenes. A nice enhancement of this would be to be able to set it up to automatically shuttle through your stations randomly. Anyway, I like Weather HD sufficiently to recommend grabbing it at least for the HD scenes, and hope to see more weather geek features in future versions. Check it out at the app store link below, and it's only 99 cents!