This Small Business Innovation Research Phase I project addresses the need for improved accuracy in the observation of atmospheric water vapor, temperature, and pressure profiles to permit better modeling of the atmosphere for weather forecasting. This can be accomplished using Differential Absorption LIDAR (DIAL) of water molecules at 1.9 »m with a narrow bandwidth (ca. 50 MHz), tunable infrared diode laser as an injection seed to a Q-switched, solid state laser. As the first step in the development of this laser instrumentation, pulse amplification of a tunable DFB diode laser over the range from 1.85 »m to 1.95 »m using a solid state amplifier will be investigated. In addition, overlap of the solid state laser gain profile with water absorption rotational lines suitable for accurate temperature measurements will be investigated. In addition to use for obtaining atmospheric water vapor, temperature, and pressure profile measurements using the 1.9 »m water absorption band, the diode laser seeding will be an improvement over the current laser technology for use in Doppler LIDAR wind measurements operating at 2.01 »m, which are not tunable and require an intricate ring laser as the injection s