Collecting Meteorological Data by Automated Surface Observing System (ASOS)

Heavy Rain From the Central Plains to the Mid-Atlantic; Heat Wave Begins This Weekend

Strong to severe thunderstorms and heavy rain will impact portions of the central Plains into the Upper Midwest and the Mid-Atlantic through the weekend. A stretch of unusually hot and humid weather is expected across portions of the central U.S. and the Southeast beginning this weekend and continuing through next week. The heat may reach dangerous levels, particularly mid to late next week. Read More >

Collecting Meteorological Data by Automated Surface Observing System (ASOS)

The Automated Surface Observing System (ASOS) program is a joint effort between the National Weather Service (NWS), the Federal Aviation Administration (FAA), and the Department of Defense (DOD). The ASOS system serves as the nation's primary surface weather observing network. ASOS is designed to support weather forecast activities and aviation operations and, at the same time, support the needs of the meteorological, hydrological, and climatological research communities. For complete details on the ASOS program, click here.

In the NWS Raleigh County Warning Area, there are 7 ASOS units, including: Raleigh-Durham (KRDU), Piedmont Triad (KGSO), Fayetteville (KFAY), Laurinburg-Maxton (KMEB), Burlington (KBUY), Rocky Mount-Wilson (KRWI), and Winston Salem (KINT).

With the largest and most modern complement of weather sensors, the ASOS system has significantly expanded the information available to forecasters and the aviation community. ASOS works non-stop, updating observations every minute, 24 hours a day, every day of the year. Getting more information on the atmosphere, more frequently and from more locations is the key to improving forecasts and warnings. Thus, ASOS information helps the NWS increase the accuracy and timeliness of its forecasts and warnings.

ASOS reports the following basic weather elements:

Sky conditions such as cloud height and cloud amount up to 12,000 feet,

Surface visibility up to at least 10 statute miles,

Basic present weather information such as the type and intensity for rain, snow, and freezing rain,

Obstructions to vision like fog, haze, and/or dust,

Sea-level pressure and altimeter settings,

Air and dew point temperatures,

Wind direction, speed and character (gusts, squalls),

Precipitation accumulation, and

Selected significant remarks including variable cloud height, variable visibility, precipitation beginning/ending times, rapid pressure changes, pressure change tendency, wind shift, peak wind.