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Midpoint Summary of Real-time PAR Experiment

The six-week 2008 Spring Real-time Phased Array Radar Demonstration in Norman, Oklahoma has reached its midpoint. The National Weather Radar Testbed Phased Array Radar (NWRT PAR) captured three severe weather events so far during forecaster operations (1 pm to 9 pm CDT, Mon-Thur).

Each week during the demonstration, up to four visiting forecasters have an opportunity to evaluate the utility of PAR data in the analysis of severe weather events. During the three real-time events earlier this month, forecasters used the PAR data to evaluate the threats of large hail, high winds, and tornadoes, and provided feedback on the operational utility of this high-temporal resolution data (1-minute volumetric scans; 24-second 0.5 degree updates). A short summary of each weather event follows.

1 May 2008: We had several tornadic supercells in Central Oklahoma today. The first storm developed just west of Norman and moved over the eastern side of the Oklahoma City metro, producing a weak tornado. Two other storms developed farther north, and at least one of these produced a signficant tornado near Ralston.

7 May 2008: In central Oklahoma several nonmesocyclonic tornadoes formed including two in northern Oklahoma City, one just 2 miles south of the National Weather Center, and one near Paoli.

13 May 2008: Storms initiated along the cold front to the NE of the Oklahoma City area and the PAR remained focused on those storms during the duration of the evening. These storms moved very slowly - remaining anchored to the front. The Norman NWS issued a number of severe warnings; one storm near Prague had some broad low-level rotation (which tightened up from time-to-time) but never drew a warning.

Significance: This evaluation of the potential operational utility of PAR is crucial to determine its suitability as a replacement technology for the WSR-88D.