The Navy Center for Interdisciplinary Remotely Piloted Aircraft Studies (CIRPAS) is collaborating with ProSensing Inc. to add a weather mode to a rapid scanning X-band phased array military radar system. The MPQ-64 radar is jointly operated by CIRPAS and the Naval Post Graduate School in Monterey, CA for the purpose of education and research, and will be equipped with a state-of-the-art FPGA-based radar control and data acquisition system for 3-D weather radar measurements. The radar can detect a 0 dBZ target from a range of 30 km with a single pulse at unity SNR with its 25 kW peak (250 W average) power TWTA based transmitter and 1.2 m diameter antenna. The radar beam is electronically (phase) scanned in elevation over a 24 deg range and over 360 deg in azimuth using a combination of mechanical and electronic (frequency) scanning. This 360x24 degree volume can be uniformly sampled in a few seconds at a resolution of 2 deg (elevation) x 1.8 deg (azimuth) x 150 m. Data products will include radar reflectivity factor and Doppler velocity mean and spectrum width from pulse pair measurements. The upgraded radar system is planned to be tested on severe storms during the 2004 spring tornado season in the US Central Plains.