ASOS vs AWOS

[just farmin]

Can't seem to find a good answer on this one anywhere. Can anybody tell me what the fundamental difference is between AWOS-3 and ASOS? Thanks

 

[A Squared]

Just off the top of my head, I can't think of any substantial difference in the information provided to the pilot by the AWOS-3 vs ASOS. The AWOS-1 and AWOS-2 have fewer sensors and provide less information. ALL ASOS's have the same set of sensors

The main difference is that the ASOS is NOAA/FAA program whereas AWOS's are usually installed by State DOTs' and other non-federal agencies (or even private entities, I suppose)

The equipment is different, and I beleive is provided by different contractors. The ASOS is is an array of seperate sensors which may be installed on ground level foundations, or may be installed on a raised platform (I've seen both) the AWOS's I've seen are a modularized unit which looks like a large aluminum teepee with sensors sticking out of the top. Those may just be the type installed by the DOT in my state, your results may vary.


regards

 

[Flymach2]

Hi...

In addition to the above post, there are a few other points.

ASOS equipment provides minute-by-minute observations of the parameters necessary to generate METARS. Although ASOS derived data you get from ATIS or from a METAR can be up to an hour old, the ASOS software is designed to transmit a SPECI report whenever it determines a significant change in conditions has occurred.

Typically , an AWOS that is connected to an FAA or NWS network transmits three reports per hour at fixed intervals. Unlike an ASOS, AWOS cannot issue a SPECI report as needed. If a major change in weather occurs between AWOS reports, you may have no way of knowing about it unless you are listening to up-to-the-minute data by radio or telephone.

AWOS-A - Reports the altimeter setting.

AWOS-1 -Also measures and reports wind speed, direction and gusts, temperature and dewpoint.

AWOS-2 -Adds visibility information.

AWOS-3 -Includes clouds and ceiling data, which essentially makes it equivalent to ASOS.

Good luck