After review of various surface observing system available on the GSA Schedule, a decision was made to procure systems from Coastal Environmental Systems, Inc.  for use at radiosonde observing stations based on the specific needs of this program.

The system will consist of the following sensors:

	Temperature (YSI, model 1074)
	Relative Humidity (Vaisala, model 45D)
	Wind Sensor (Vaisala / Handar Heated Ultra Sonic, model 425AHW)

The temperature and relative humidity sensors will be contained in a forced-air (motor) aspirated radiation shelter (model 1075).

A precision digital barometer  was purchased separately and is already in operation at radiosonde observing stations.

The system will transmit information back to the computer system via a one-way radio link.   The system will include a Zeno-3200 Data Logger, with 24-hour battery backup.  The electronic components will be located in a stainless steel enclosure.