August 12, 2002: Weak line of cells and Biological Scatterers Author: Pam Heinselman, CIMMS/OU Last Updated: 17 April 2003

Forecast/Weather:

On 12 August, a line of weak cells is observed north of KOUN. There is also a small area of stratiform precipitation just northeast of KOUN. These precipitation areas form ahead of a shortwave trough in the westerlies, move southeastward, and begin to dissipate. Interference from another radar is apparent, along with an area of biological scatterers just southeast of KOUN for the duration of the dataset. A gust front is produced by one of the stronger cells between 17:18-18:25.

Radar Operations:

Start time: 14:50 8/12/02 UTC (09:50 8/12/02 local time)
Stop time: 18:41 8/12/02 UTC (13:41 8/12/02 local time)

Radar/Operational Status:

Radar: Calibration appears high. Hydrometeor Classification Algorithm: Warm season

Operational Delivery:

Not applicable.

Snapshots:

Polarimetric data at 15:21 UTC 12 August 2002 shows a short line of convective cells with trailing stratiform north of KOUN, stratiform precipitation northeast of KOUN, biological scatterers southeast of KOUN, and interference northwest of KOUN (Figs. 1-4). Snapshots of the gust front produced by one of the stronger cells is also shown (Figs. 5-8)

Figure 1: Radar reflectivity data at 15:21 UTC 12 August 2002.	Figure 2: Differential reflectivity data at 15:21 UTC 12 August 2002.
Figure 3: Correlation coefficient at 15:21 UTC 12 August 2002.	Figure 4: Output from the hydrometeor classification algorithm at 15:21 UTC 12 August 2002.

Figure 5: Radar reflectivity data at 17:18 UTC 12 August 2002.	Figure 6: Differential reflectivity data at 17:18 UTC 12 August 2002.
Figure 7: Specific differential phase at 17:18 UTC 12 August 2002.	Figure 8: Output from the hydrometeor classification algorithm at 17:18 UTC 12 August 2002.