NOAA Hi-Def Radar 1.0

the author of this app says:

Simple yet powerful app for viewing real-time animated weather radar images in vivid color on a highly responsive interactive map, with higher resolution images than any other radar app in the appstore. Jaggies begone!

Plus this is the only NOAA radar app that shows snowfall on the map!

Plus get weather forecast from the same screen!

Plus this is the only app that automatically augments land-based radar images with latest images from NOAA satellites covering the Atlantic/Pacific oceans into one single screen. This lets you track and follow the upcoming hurricanes and storms all from the same map.

Works flawlessly on iOS5!

Install and go, no complex setup
Sharp images even on retina displays (when zoomed upto a certain point)
Fast Loading
Real-time. Shows the latest Radar images within minutes of being gathered.
Check the current weather + forecast for any point on the map
Intuitive Play/pause/manual modes for moving between frames.
Always shows both time-stamp and "minutes ago" with each frame to prevent any confusion while viewing the loop.
Select opacity of radar images to your taste
Check your local radar site's hardware operational status from within the app
Portrait/Landscape
Get fast support from within the app

Coverage Notes: If you live in a very-high-altitude town in Colorado (e.g. Fraser, Vail), it is highly likely this app will not meet your needs since radar beams get blocked by the tall mountains. Also Alaska coverage includes only the coastal areas, and does not include the Aleutian Chain.

Notes:
This app is only useful for users in the US, including all 50 states and territories including Puerto Rico and Guam.