Radar Displays

Product Menus for Radar Products

The menu bar at the top of the D-2D perspective contains numerous menus to load radar products and associated tools. This section focuses on the menus for loading the main suite of radar products for dedicated radars where all radar products are available.

Menus for Specific Dedicated Radars

At a WFO, each dedicated radar for your CWA appears as a separate product menu. If you have any Terminal Doppler Weather Radar (TDWR) sites in your CWA, then you will see menus for each of those radars as well. All base and most derived radar products from a given radar will be listed under a menu labeled with that site’s four-letter identifier (e.g., kabr, pahb, tmco). CONUS radars start with k. OCONUS radars start with p. TDWR radars start with t. NOTE: Additional non-dedicated radars may appear next to your dedicated radar menus depending on your local office’s D-2D perspective menu configuration.

The “Radar” Menu: Non-dedicated Radars and Mosaic Products

The Radar menu contains menus for radar mosaics and two different types of non-dedicated radars (radars with no local RPG access). The top section of the Radar menu contains submenus for the few FAA ASR-11 and ARSR-4 radars the NWS has access to (only relevant for a few CWAs).

The second section of the Radar menu contains the national and regional mosaics. The national and regional mosaics assemble a mosaic radar display on the fly using existing individual radar files stored locally in EDEX, though they have access to a different set of products. The regional mosaics use all the regional radar "NIDS" ingest, which includes the lowest four tilts of Legacy and Dual-Pol data. The national mosaics use only a limited set of radar products ingested locally for all radars nationwide (WSR-88D CZ, STI, Z&V 0.5 and 1.3/1.5 degrees; TDWR 0.6 degree long-range Z and 1.0 degree Z and V). The Canadian radars (data distribution on hold) and TDWR radars are also available under the Regional and National Mosaics.

The Radar menu mosaics use the maximum value at a point from any radar, so it is not uncommon for some of the Dual-Pol mosaics to be strange where a higher values of ZDRs are plotted from a farther radar (higher height) can be plotted over a nearby radar that is sampling lower values of ZDRs in lower-levels. The main benefit of the mosaics in the Radar menu is that they cover the whole US (good for tracking precip across the whole US), and they contain some other radar products (Dual Pol variables, Echo Tops, etc.) not found in more sophisticated AWIPS radar mosaics like Multi-Radar Multi-Sensor (MRMS) in the MRMS menu next to the Radar menu. 

The third section under the Radar menu contains products from non-dedicated radars under the Radar->Dial Radars menu. These menus look like the dedicated radar menus, but only a limited set of radar products are available in the dial radar menus. As stated above your regional dial radars will have more products than the national radar ingest for radar outside your region.

Typically, if a radar product is available, the latest day and time are listed in the menu (e.g. 24.2154). If a radar product is missing, the menu usually displays --.---- (unless there is a problem with the menu updates). To verify no radar data exists, it is usually a good idea to attempt to load the product and watch for an error message.

Typically, forecasters want to load the highest resolution raw radar data in polar coordinates for warning decision making over localized areas. The dedicated radars have the greatest amount of high-resolution data, and the dial radars have a smaller subset of the dedicated radar stream. Mosaics are useful for tracking features that cross multiple radars over time. The MRMS mosaics cover WFO's local region, have higher temporal resolution (2 min), have some unique products (Maximum Expected Hail Size), and use a better mosaic approach than the Radar menu mosaics. The regional mosaics under the Radar menu will contain more radar products, including Dual Pol products. The national mosaics under the Radar menu mosaics are the only ones to cover the whole U.S., but they have the most limited set of products (mainly low-level Z, V, CZ, and STI).

The “MRMS” Menu: Multi-Radar Multi-Sensor Mosaic Products

The MRMS menu contains a unique suite of mosaic products that are created outside of AWIPS differently from the mosaics in the Radar menu. While the mosaics under the Radar menu read in radar products and mosaic them on the fly, the MRMS mosaics are created outside of AWIPS using sophisticated techniques. There is a course on MRMS that is included in the Convective Storms Structure and Evolution topic in RAC that will go into more detail of these products. For AWIPS Fundamentals, you should be comfortable loading radar products from the individual radar menu as well as simple mosaics from both the Radar and MRMS menus.

All Tilts

This lesson provides information on All Tilts radar products. Besides explaining the steps for loading this product and interrogating storms, this lesson also incorporates some best practices for using All Tilts products during warning operations.

What Are All Tilts Products?

All Tilts products are loops of radar base data in AWIPS where every available elevation angle for each volume scan is loaded in a frame sequence. The operator uses the arrow keys on the keyboard to step through the products for either a constant elevation angle or volume scan.

Important Points to Remember When Using All Tilts Products

Avoid using WarnGen with all tilts products

In general, WarnGen should be loaded on a display panel with single elevation angle product, not an All-Tilts product. All-Tilts products offer a limited number of volume scans in the frame loop to determine storm motion. Loops of single elevation angle products are better suited for that purpose. Use All Tilts products to interrogate storm structure instead.

For non-dedicated radars, use Radar Multiple Requests to have access to all 8-bit base data

When interrogating storms that are best covered by a non-dedicated radar, remember to use Radar Multiple Requests (RMRs) to download the 8-bit base data from those radars. This process ensures having the best quality data from those radars for storm interrogation.

Set the frame count to 64+

To maximize the effectiveness of All Tilts products for interrogating storms or other deep phenomena, set the frame count to 64 frames or larger. This change provides at least 3-4 full volume scans of base data available for storm interrogation.

If lost, go to the last frame

Because of the nature of the product, users can get confused to which volume scan is the latest, etc. If you find yourself in this situation, click on the last frame button (or use Ctrl + right arrow) in the CAVE toolbar to move to the last frame in the loop. This process ensures you’re viewing data from the latest volume scan.

Pay attention to SAILS and MRLE tilts

SAILS provides an extra 0.5 degree scan, while MRLE allows the user to re-scan the lowest "N" elevations (where N can be either 1, 2, 3, or 4). The extra 0.5 degree SAILS and MRLE tilts do not have full volume scans available with the same time step, so it is good to pay attention to the SAILS and MRLE labels in the text legends in the upper part of the display. If you navigate up from an extra SAILS or MRLE tilt, you will go to the next higher tilt from the original volume scan (just like GR2 Analyst). While previous versions of AWIPS had different behavior managing the SAILS and MRLE tilts, the latest version is just like GR2 Analyst and is easy to get used to (unless you revert back to the old behavior by deselecting the default Enable SAILS Frame Coordinator in the Radar Display Controls loaded from the Tools menu).

Four-Panel All Tilts Displays

AWIPS supports the use of all tilts products being displayed in a single-panel and four-panel layout. There is one issue to remember with the four-panel All Tilts displays. If you manually load radar products into the four-panel, you have the ability to combine All Tilts products with other products that are generated only once per volume scan. CAVE time matches all products to the time listed in the first product loaded (unless the user changes that). To avoid any problems with All Tilts and volumetric products in the same display, it is recommended to load All Tilts products first. However, in the event you load a less frequently updating product first, recall that you can always change which product is used for Time Matching.

Radar Products In Volume Browser

Vertical Wind Profile hodographs and radar cross-sections can be displayed using the Volume Browser. The Volume Browser has no radar selector, so it uses the cursor home tool available from the Tools menu to identify the nearest radar to use.

Vertical Wind Profile (VWP) Hodographs

VWP hodographs are generated using the Volume Browser. The hodograph is displayed next to a windspeed vs pressure plot. In addition to moving the cursor home to a location near the radar, a Tools menu point must be moved to the location of the radar to be able to select the location to the load the VWP for.

Reflectivity and Velocity Cross-Section

While the FSI Tool is best suited for creating dynamic vertical or horizontal cross sections, the Volume Browser can be used to create vertical and horizontal cross sections as well as radar mapped to user-defined temperature coordinates (e.g. Z on -20C). The Volume Browser cross-sections will include topography and can be combined with other AWIPS data in more flexible ways than in FSI which is outside of CAVE.