The NWS gets current conditions from 2 places.
As far as I know they never use model data for current conditions.
The first one is AWOS or Automated Weather Observing System.
Just click on the map and it will show you the identifier for each station.
https://www.faa.gov/air_traffic/weather/asos/The second one is COOP or Cooperative Observer Program.
After reading about it click on Current Conditions. This will take you to a national map
where you can get down to your local area where it will show you what type of station is used for your current condition.
http://www.weather.gov/rah/coopYou have to be careful about what station is used for your condition. You may be 5 or 10 miles from the reporting station so things could be different in your back yard. This is called a micro climate. The geography of the land and other factors dictates what your current weather will be. That is the reason we all have weather stations. Because we want to know what the weather is at our location.
There are several other non official weather station sites such as Weather Underground and CWOP which use personal weather station data. While most owners of these stations try to get the best readings they can they are limited by not having the best siting conditions and not all owners are vigilant enough to maintain their sites properly so you have to use this data carefully.