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Weather Systems
Quick Links
NEXRAD RADAR
The NEXRAD frequency shift of the RADAR signal can measure: precipitation, wind,
wind shear, tornadoes, mesocyclones, thunder storms, turbulence, hail, and clean
air. Maximum measurement range for reflectivity (moisture) is 248 miles and
70,000'. Maximum velocity measurement range is 124 miles and 55,000'. System
has the capability to dial up another RADAR dish and get near real-time data
for use in long range weather forecasting.
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PUP |
Open architecture Principle User Position (OPUP) is currently being tested to modify the NEXRAD weather radar system
FMQ-13 Digital Winds
Uses 4 heated wires to measure wind direction and speed. Wires are heated to
100 deg. Celsius above ambient temp. Computes wind data by measuring current
required to keep wires at reference. Each sensor samples data 4 times a second
for 5 seconds, creating a 5 second average (20 samples). The master indicator
polls each sensor (4 max) every 5 seconds and uses this data to display direction
and speed, and to compute gusts, variability and spread. System can measure
direction from 0-360 +/- 3 degrees and speed up to 150 knots.
FMQ-8 Temp/Dew point
Sensor uses one of two methods to compute temperature and dew point. First method
uses chilled mirror theory, where a small metal mirror is heated/cooled to find
the temp at which moisture condenses on the mirror (dew point temp). The other
method uses a variable capacitive sensor to compute dew point. Both systems use
a temperature sensitive resistor to measure ambient temps. Either system is
capable of measuring temp/dew point from -100 to +100 deg C.
GMQ-32 Transmissometer
System has a projector and receiver located 250'-500' apart (base line). Projector emits a calibrated beam of light to the receiver. The receiver measures the amount of light remaining as it crosses the base line (losses due to fog, smoke, dust, etc). Data is converted to voltage pulses from 0-4000 pulses per minute , (which equates to 0-100% visibility (or 0 - > 25 miles)) and sent to the indicators.
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FMN-1A Runway Visual Range
An indicator that is used in conjunction with the GMQ-32's to provide a digital visibility reading. The system computes visibility every minute and displays both current and 10 minute average readouts from 600 to 6000'. Observers can manually select airfield lighting steps as a visibility offset, or the system can be made fully automatic by connecting it to the airfield lighting system and a light intensity detector.
CT-12K Laser Ceilometer
System
emits an infrared laser beam straight up into the sky and measures echo return
time. Time of echo delay is used to compute lower two cloud layers from 0-12,600'
in 50' increments. Cloud heights are checked every 12 seconds, and will only
identify clouds directly over the sensor.
ASOS (Automated Surface Observing System)
A
stand alone weather observation system that monitors: quantity and type of precipitation,
temperature/dew point, visibility, cloud height, wind direction/speed, and barometric
pressure. The system takes measurements automatically and transmits the data
every hour for use in forecasting. In addition, it has the capability of direct
radio broadcast (ATIS) to local aircraft via a computer generated voice.
| More Info | NWS ASOS News/Info | Implementation schedule |
New Technologies
The National Weather Service has been working on a major modernization /restructuring program since the late 1980's. This program incorporates many elements with the major goal of increasing the accuracy and timeliness of its weather forecasts. NWS meteorological development
To increase the timeliness, the agency has increased its use of GOES (Geostationary Operational Environmental Satellites) and has been working to establish a vastly improved inter-active communications link, called AWIPS (Advanced Weather Interactive Processing System).
To increase accuracy, the agency has incorporated new instruments to include: WSR-88D NEXRAD weather RADAR, and ASOS (Automated Surface Observation System).
Open architecture Principle User Position (OPUP) is currently being tested to modify the NEXRAD weather radar system
NOAA's Systems Acquisitions Office
National Aviation Weather Initiatives