RPS List Decision Aid - VCP 11, 12, 211, & 212

Overview

In theory, you would be using VCP 12/212 and 11/211 for similar situations: convective events. In practice, VCPs 12/212 will normally be your go-to during convective weather because of its better sampling of the lower-levels of the atmosphere. VCPs 11/211 can still be useful at sampling deep convection because of its slightly better sampling of the midlevels at certain ranges. RPS lists between the two will be similar since they are used in similar situations. Besides their different elevation angles, the most important difference between these VCPs is 12/212 incorporates SAILS tilts. For simplicity, only a sample list for VCP 12/212 angles are provided as an example below. A VCP 11 RPS list would look similar to the one below, but the corresponding elevation angles would be different, and there is no need for the duplicate base product entries for the SAILS tilts.

Because these VCPs are generally run during severe convective events, offices must balance two concerns. Forecasters normally want every product they can get to meet their needs during the worst, high-end convective events. However, some narrowband connections (e.g., FAA primary, supplemental, and temporary backup) may not be suitable to meet this approach. The list below represents the "everything and the kitchen sink" list that should work for most NWS and DoD primary AWIPS connections. RPS lists for other connections will need to prioritize based on your needs.

We provide a detailed list below of recommend products. This list may not work for everyone. Here are some important details to keep in mind when looking over this list:

  • Extra Entries for SAILS Tilts: Remember that requesting all elevation angles (i.e., "All") will not request the SAILS tilts for that product. To ensure you receive all the SAILS tilts, when requested, you need a second entry in the RPS list for each base product. This entry requests just the 0.5 degree tilt, but for all of the cuts (i.e., "Cuts All"). Most of the base products have this extra entry already included in the national RPS list. However, you will need to add these entries for Super-Res Z (153), Super Res V (154), Super Res SW (155), and Raw CC (167).
  • No 8-bit Z (94): The RPG generates Super-Res Z (153) products now for every elevation scan even though only the split cuts technically have super resolution data. The resolution from Z(153) is preferrable to Z(94), and downloading two versions of the same data could result in loadshedding on a slow connection. So, the exmaple below doesn't include Z(94).. If you find that you are still running into loadshedding issues after implementing this solution, consider swapping out some of the higher tilt Z(153) products, maybe tilts above 10 degrees, for Z(94). That will still allow you to perform a full volume analysis, but free up a little more bandwidth.
  • Super-Res Spectrum Width (155): WDTD has long been a proponent of using Spectrum Width as part of your base data analysis. We also want forecasters to look at the highest resolution data possible. However, we must be pragmatic, too. SW (155) products can be very large (i.e., up to 20 times the size of the lower resolution Spectrum Width products). If you have issues with loadshedding, you will want to stick with the combo suite of SW(28)-SW(30) at all tilts.
  • Raw CC or SDC (167): In most cases, forecasters will want to look at CC(161) to analyze the Correlation Coefficient data. The primary benefit of using Raw CC (167) is that forecasters might be able to identify a TDS more quickly. These files can be up to twice as large as the standard CC products, so include Raw CC (167) judiciously in your RPS list. There is a definitely a benefit to including the product for the lowest tilt. If you have the bandwidth, you may want to include more tilts. However, don't foresake the standard CC products just so you can get all of the Raw CC tilts.

 

Products NOT included: 4-bit (16 level) SRM is not included because with a LAN-LAN connection there is no reason not to use 8-bit SRM after receiving the 8-bit Velocity products. 8-bit SRM is in every way superior to 4-bit SRM. Nevertheless, the lowest 4 tilts in VCP 11/211 and the 0.5, 1.3, 2.4, and 3.1 tilts (and 6 tilts in VCP 12/212: 0.5, 0.9, 1.3, 1.8, 2.4, and 3.1) will still be available since they are added via the National RPS list. Snowfall products are not included but could be if needed.

The list below contains 138 Products, and combined with the national set a total of 212 products would be requested.

Sample VCP 12/212 Local RPS List

NOTE: This sample list could also be used to produce a local list for VCP 11 and 211 by changing the elevation angles

ID Code Elevation Angles Product Description Reason to Include
28 SW 1.8, 2.4, 3.1, 4.0, 5.1, 6.4, 8.0, 10.0, 12.5, 16.8, 19.5 8 Level 0.25 km (0.13 nm) Base Spectrum Width (range to 32 nm) More base data. Included all elevation angles since the products are small and you never know when you may need a SW product close to the radar but at a high altitude.
30 SW 1.8, 2.4, 3.1, 4.0, 5.1 8 Level 1 km (0.54 nm) Base Spectrum Width (range to 124 nm) Included these for further range capabilities. Dropped off a few more elevation angles because they would be very high at 64 nm. As with product 28, 0.5 is already included in the National RPS list.
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 V All Tilts 256 Level, 0.25 km (0.13 nm) Base Velocity  
143 TRU 0.5, 0.9, 1.3, 1.8, 2.4, 3.1, 4.0, 5.1, 6.4, 8.0, 10.0, 12.5, 16.8, 19.5 Tornado Detection Rapid Update Product (Graphic Output) Available every elevation angle. Small products so won't hurt having every elevation angle, especially if severe convection exists very close to the radar.
149 DMD 0.5, 0.9, 1.3, 1.8, 2.4, 3.1, 4.0, 5.1, 6.4, 8.0, 10.0, 12.5, 16.8, 19.5 Mesocyclone Detection Data Array Product (Graphic Output) The newest version of the MDA that is available at the complete of each elevation angle scan. Also, SCAN DMD uses these products.
153 HZ All Tilts Super Resolution Reflectivity You want the highest resolution base data you can get during severe weather operations.
153 HZ 0.5 for SAILS 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.
154 HV 0.5 for SAILS Super Resolution Velocity You want the highest resolution base data you can get during severe weather operations.
155 SW All Tilts Super Resolution Spectrum Width You want the highest resolution base data you can get during severe weather operations.
155 SW 0.5 for SAILS Super Resolution Spectrum Width You want the highest resolution base data you can get during severe weather operations.
159 ZDR 4.0, 5.1, 6.4, 8.0, 10.0, 12.5, 16.8, 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 4.0, 5.1, 6.4, 8.0, 10.0, 12.5, 16.8, 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 4.0, 5.1, 6.4, 8.0, 10.0, 12.5, 16.8, 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 4.0, 5.1, 6.4, 8.0, 10.0, 12.5, 16.8, 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 4.0, 5.1, 6.4, 8.0, 10.0, 12.5, 16.8, 19.5 Melting Layer (Graphic Output) Supplements the dual-pol base data from the national RPS list.
167 SDC (Raw CC) 0.5, 0.9, 1.3, 1.8 256 Level Non-Filtered Correlation Coefficient May help some forecasters spot a TDS more quickly, but the data is VERY noisy
167 SDC (Raw CC) 0.5 for SAILS 256 Level Non-Filtered Correlation Coefficient May help some forecasters spot a TDS more quickly, but the data is VERY noisy