Welcome to http://madis-data.noaa.gov/cap
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Cooperative Agency Profilers (CAP) is a cooperative venture between GSD (formerly FSL) and many participating agencies enabling GSD to; acquire profiler and RASS data in near real-time, apply GSD's data quality control algorithms, and make these value-added data available on the web and to the National Weather Service. At this time, data from approximately 100 CAP sites from over 35 different agencies from around the world are being acquired by GSD. The majority of CAP systems are 915 MHz Boundary Layer Profilers, there are also several 449 MHz and 50 MHz profilers in the CAP network.

The current status of CAP sites in the continental US are shown on the map below. Stars represent sites that produce both wind and RASS data. Circles represent sites that only produce wind data. The colors of symbols represent how recently data from a site has been acquired (refer to legend above map).

Current  1-3 Hour  4-24 Hour  25-72 Hour  >72 Hour
Map of CONUS showing locations of operational CAP stations
Current Operational CAP Stations in the Continental US.
(Mouse-over site locations for information about the site)

Boundary Layer Profilers also referred to as BLPs are small, relatively low-cost UHF Doppler radars used primarily to measure vertical profiles of horizontal winds. The BLPs have a minimum range of about 100 m above ground level (AGL), with range resolutions selectable from 60 m to 400 m. Depending on the configuration of the radar, and the atmospheric conditions, BLPs are capable of measuring wind up to about 3-5 km AGL. With the addition of an optional Radio Acoustic Sounding System (RASS), virtual temperature profiles up to about 1 km can also be obtained.

Unlike the radars used in the NOAA Profiler Network, the CAPs sites are operated in many different ways, are owned by about 30 different agencies, and are optimized for different applications. Most BLPs report hourly winds, although some may generate wind profiles as often as every 10 minutes. The radars may be in fixed locations and operated continuously, or they may be portable, and operated only during field campaigns. Therefore, the list of profilers available via our Web displays will be dynamically updated.

Normally, raw CAP data files are time-stamped using the starting time of their acquisition period. Data time-stamps used for data displays on this site are always the end-time of the acquisition period. The winds displayed at each height are averaged over the preceding hour (in the case of hourly winds), e.g., sub-hourly data processed between 1600-1700 UTC would be averaged and displayed with the time stamp of 1700 UTC. The displayed winds have all "passed" our single-station quality control requirements (continuity in height and time, and a requirement that good vertical beam data is present) and typically represent high quality data. RASS temperatures follow the same time stamp convention and have also passed single-station quality control. BLP Web products are created based on the reporting periods of a radars ranging from 1-hour to 10-minute cycles. Generally hourly resolution data are available by 30 minutes past the hour, and 30-minute resolution data are available 20 minutes past the end of their cycle.

Typical Boundary Layer Profiler with RASS
Typical 915 MHz Boundary Layer Profiler with RASS
(Photo Courtesy of Argonne National Laboratory)

449 MHz 1/4 Scale BLP
449 MHz Profiler at TARS Site in FT. Huachuca, AZ
(Photo Courtesy of ESRL/PSD)

50 MHz Profiler
50 MHz Profiler at Lamont, OK
with RASS in foreground
(Photo Courtesy of ARM)