RPS List Decision Aid - VCP 121, 221, and 21

Overview

VCPs 121, 221 and 21 have identical elevation angles, thus RPS lists for one will work with the others. VCPs 121, 221, and 21 are useful for widespread non-severe convection or an approaching tropical cyclone, or for non-severe precipitation events, including snowfall. The ROC-issued WSR-88D Tropical Cyclone Operations Plan (TCOP) provides detailed information about VCP selection in Section 4 of the plan. Click the link above for the full PDF document. With vast differences between tropical and winter stratiform environments, it may be a good idea to set up 2 RPS lists for 121 (which then could be used for 221 and 21): one that would be for tropical cyclones/deep non-severe convection and another for stratiform non-severe events. Guidance will cover both types of RPS lists.

Products NOT included in the convective/tropical RPS list: Snowfall products are left off this guidance, although there is room to add them if you like. SRM is not included because with a LAN-LAN connection there is no reason not to use SRM after receiving the 8-bit Velocity products. 8-bit SRM generated on AWIPS is in every way superior to RPG SRM products. Nevertheless, the lowest 4 tilts of SRM in VCP 121 ( 0.5, 1.5, 2.4, and 3.4) will still be available since they are added via the National RPS list.

The RPS list for 121, 221, and 21 in expected wide-spread convective/tropical storm situations contains 73 products and added to the 74 national products, there is space for 153 more local products. You could easily add the snowfall products here, although the 2nd list for VCP 121 is a much better choice for stratiform cool season precipitation because it does not contain any of the rotational products.

 

Sample Local RPS List for Widespread Convective/Tropical Events Using VCP 121, 221, & 21

ID Code Elevation Angles Product Description Reason to Include
33 HSR Hybrid Scan Product 16 Level, 1 km (0.54 nm) Hybrid Scan Reflectivity Consistency check to see what's getting into precip products.
79 THP Hybrid Scan Product 16 Level, 1 km (0.54 nm) Surface Rainfall Accumulation, 3 Hour Duration Longer duration product.
99 DV 4.3, 6.0, 9.9, 14.6, 19.5 256 Level, 0.25 km (0.13 nm) Base Velocity No substitute for 8-bit base data products, especially for the proper interpretation of deep, moist convection.
143 TRU 0.5, 1.5, 2.4, 3.4, 4.3, 6.0, 9.9, 14.6, 19.5 Tornado Detection Rapid Update Product (Graphic Output) Available every elevation angle. Small product so it won't hurt having every elevation angle, especially if severe convection exists very close to the radar.
149 DMD 0.5, 1.5, 2.4, 3.4, 4.3, 6.0, 9.9, 14.6, 19.5 Mesocyclone Detection Data Array Product (Graphic Output) The newest version of the MDA that is available at the completion of each elevation angle scan. Also, SCAN DMD uses these products.
153 HZ 0.5, 1.5, 2.4, 3.4, 4.3, 6.0, 9.9, 14.6, 19.5 Super Resolution Reflectivity You want the highest resolution base data you can get during severe weather operations.
154 HV 0.5, 1.5, 2.4 Super Resolution Velocity You want the highest resolution base data you can get during severe weather operations.
155 SW 0.5, 1.5, 2.4, 3.4, 4.3, 6.0, 9.9, 14.6, 19.5 Super Resolution Spectrum Width You want the highest resolution base data you can get during severe weather operations.
159 ZDR 4.3, 6.0, 9.9, 14.6, 19.5 256 Level, 0.25 km (0.13 nm) Differential Reflectivity Supplements the dual-pol base data from the national RPS list.
161 CC 4.3, 6.0, 9.9, 14.6, 19.5 256 Level, 0.25 km (0.13 nm) Correlation Coefficient Supplements the dual-pol base data from the national RPS list.
163 KDP 4.3, 6.0, 9.9, 14.6, 19.5 256 Level, 0.25 km (0.13 nm) Specific Differential Phase Supplements the dual-pol base data from the national RPS list.
165 HC 4.3, 6.0, 9.9, 14.6, 19.5 256 Level, 0.25 km (0.13 nm) Hydrometeor Classification Supplements the dual-pol base data from the national RPS list.
166 ML 4.3, 6.0, 9.9, 14.6, 19.5 Melting Layer (Graphic Output) Supplements the dual-pol base data from the national RPS list.
167 Raw CC 0.5 256 Level Non-Filtered Correlation Coefficient May help some forecasters spot a TDS more quickly, but the data is VERY noisy.

 

Products NOT Included in the stratiform RPS list: None of the rotational products are included because, by choice, the following RPS list should be used for widespread stratiform non-convective precipitation, and rotational products would actually be distractors. For example, say the MDA is showing numerous false mesos along an arctic cold front. This list leaves all MDA products off so you would not see any annoying alarms or false detections. As with the other list, SRM is not included since you have access to 8-bit SRM.

The following list contains 57 products, and when combined with the 74 national products, there is still room to add an additional 169 products.

 

Sample Local RPS List for Stratiform Non-Convective Events Using VCP 121, 221, & 21

ID Code Elevation Angles Product Description Reason to Include
33 HSR Hybrid Scan Product 16 Level, 1 km (0.54 nm) Hybrid Scan Reflectivity Consistency check to see what's getting into precip products.
79 THP Hybrid Scan Product 16 Level, 1 km (0.54 nm) Surface Rainfall Accumulation, 3 Hour Duration Longer duration product.
99 DV 4.3, 6.0, 9.9, 14.6, 19.5 256 Level, 0.25 km (0.13 nm) Base Velocity No substitute for 8-bit base data products, especially for the proper interpretation of deep, moist convection.
144 OSW Hybrid Scan Product 16 Level, 1 km (0.54 nm) One-hour Snow Accumulation (Water Equivalent) In case it snows, be sure to reset accumulation at the RPG, it is not done automatically.
145 OSD Hybrid Scan Product 16 Level, 1 km (0.54 nm) One-hour Snow Accumulation (Depth) In case it snows, be sure to reset accumulation at the RPG, it is not done automatically.
146 SSW Hybrid Scan Product 16 Level, 1 km (0.54 nm) Storm Total Snow Accumulation (Water Equivalent) In case it snows, be sure to reset accumulation at the RPG, it is not done automatically.
147 SSD Hybrid Scan Product 16 Level, 1 km (0.54 nm) Storm Total Snow Accumulation (Depth) In case it snows, be sure to reset accumulation at the RPG, it is not done automatically.
153 HZ 0.5, 1.5, 2.4, 3.4, 4.3, 6.0, 9.9, 14.6, 19.5 Super Resolution Reflectivity You want the highest resolution base data you can get during severe weather operations.
154 HV 0.5, 0.9, 1.3 Super Resolution Velocity You want the highest resolution base data you can get during severe weather operations.
155 SW 0.5, 1.5, 2.4, 3.4, 4.3, 6.0, 9.9, 14.6, 19.5 Super Resolution Spectrum Width You want the highest resolution base data you can get during severe weather operations.
159 ZDR 4.3, 6.0, 9.9, 14.6, 19.5 256 Level, 0.25 km (0.13 nm) Differential Reflectivity Supplements the dual-pol base data from the national RPS list.
161 CC 4.3, 6.0, 9.9, 14.6, 19.5 256 Level, 0.25 km (0.13 nm) Correlation Coefficient Supplements the dual-pol base data from the national RPS list.
163 KDP 4.3, 6.0, 9.9, 14.6, 19.5 256 Level, 1 km (0.54 nm) Specific Differential Phase Supplements the dual-pol base data from the national RPS list.
165 HC 4.3, 6.0, 9.9, 14.6, 19.5 256 Level, 1 km (0.54 nm) Hydrometeor Classification

Supplements the dual-pol base data from the national RPS list.
166 ML 4.3, 6.0, 9.9, 14.6, 19.5 Melting Layer (Graphic Output) Supplements the dual-pol base data from the national RPS list.