[id10t]

Determine your true lat/long (instead of using the GeoLocationByIP function) and just plug it in as the RealLatitude and RealLongitude variables

private static void InitLocation()
{
AskGeoService askGeo = new AskGeoService();
weatherData = new WeatherUndergroundData("d0", RealLatitude, RealLongitude);

askGeo.queryLocation(RealLatitude, RealLongitude);

int minutes = (int)(askGeo.currentOffserMS / 1000 / 60);
Debug.Print("\tTimezone offset (+DST)=" + minutes + " minutes");
ntpService.SetTimeZoneOffset(minutes);
}

I'd also wrap the whole thing up in a check, first by using the GeolocationByIP function, prompting the user to either accept that location as "close enough" or entering a more correct location and then doing the query for the actual weather data.