I think that Weather Report should pop open a small notification when hazardous weather alerts are issued for the user's locality. This literally has the possibility to save lives.

Specifically, a little notification would appear, similar to when new updates are available (e.g. in Ubuntu). It would display the hazardous weather warning, e.g. "A tornado watch has been issued for your area until 2 a.m."

In the U.S., this information is published in plaintext by the National Weather Service, the same source of information from which Weather Report currently pulls information. Upon viewing Details -> Forecast, the first line will display any alerts currently in effect (e.g. "FREEZE WARNING IN EFFECT UNTIL 8 AM EST THIS MORNING"). So this information is available and currently pulled by Weather Report, it's just not used in any way that is particularly useful to the user. But these alerts can be vitally important. (For instance, I thought of this issue when recently in my area, there were tornados which killed several people.)

It should be optional to turn on/off these notifications, if the user does not prefer them. (Especially if a user has multiple Weather Report applets for different locations -- they can only be physically in one of those places at the time, and likely do not want to see alerts for other locations.) In addition, it should be optional which notifications to display. For instance, I live in Florida -- it is quite common to be under "Thunderstorm Watch," and I am not particularly interested in seeing such notifications. However, I am extremely interested in being notified of a Tornado or Hurricane Warning. A list of such events published by the NWS is here:

http://www.weather.gov/alerts/product_list.txt

In addition, the NWS is experimentally publishing these alerts in XML:

http://www.weather.gov/alerts/

I think this would be an extremely valuable feature for users in those localities where it would be possible to implement. (This includes at least the U.S., which is a very large user base and influential market.)