Configuring WARN Products

In the main menu bar, select Menus > Product Configuration.

In the main menu bar, select Type > WARN.

The WARN Product Configuration menu opens.

In Warning Symbol, specify the text used in the warning messages and the text displayed at the centroid position on the situation display.

For example, the text may be, HAIL or MBW, S++, or TRW+.

Enter the minimum size of a thresholded region in the Area in Sq Km field.

Areas that do not meet or exceed this size are discarded. Enter the desired value in square km.

For example, for a 3 km by 3 km (1.9 × 1.9 mi) size area, enter 9.

Select the button next to Product Type and Product Name, select up to 3 products to be examined by the WARN product.

Products must have the same maximum product range per the respective Product Configuration menus.
Products must have the same resolution per the respective Product Configuration menus.
Products must be of a supported data type: dBT, dBZ, dBZc, Height, Kdp, LDRH, LDRV, R, Rain, RhoH, RhoV, RhoHV, Shear, SQI, Time, VIL, Width, and ZDR.

Errors are reported at run time in the Radar Status menu.

Select the product type.

The Product Name information is filled in automatically. You can also edit the name.

Select the product name.

The list of product names shows products currently in your system. If the product you want does not show, run your system until it does show.

Alternatively, chose a different product of the desired type and override the product name.

For each product, use Time values to use products from different tasks or different runs of the same task.

Use the plus and minus buttons to increase or decrease the hours, minutes, or seconds or type a time value in the window.

This field applies only when there is more than one criterion. For example, if the second criterion has a time of 00:10:00, when the first product becomes available, the scheduling algorithm searches back in time as far as 10 minutes to find a version of the second product.

You must know your task schedule. If you use products based on different tasks, you must set the Time field to some nonzero number or the product does not run. In general, if all of your product criteria are based on the same task, set all the times to 00:00:00 so that only data from the same run are used.
For each product, enter the warning threshold in Threshold.
The WARN product considers only those values that meet or exceed the threshold. The units of measure depend on the selected product. For example
- TOPS thresholds are specified in km
- VIL thresholds are specified in mm.
Check the appropriate Product Configuration menu if you are uncertain about the units of measure.

The WARN product operates on the color bands in the product image and the threshold is set accordingly.

For example, to set up a reflectivity warning based on a CAPPI product.
- Display an example of the product.
- Choose your threshold to match the number displayed with the color band that you want to use as your threshold.
If 45 dBZ is the number displayed with the red color, and you set your threshold to 45 dBZ, then all of the regions displayed as red (or "greater") are included in the warning algorithm. This is convenient for verifying the algorithm. If you display the reflectivity product along with the situation display (warning overlay), the centroid labels are positioned precisely in the red-colored regions.

For the VVP product, the threshold refers to the divergence in units of m/s per km (10^-3 s^-1). When the WARN product is run for the VVP, a warning is generated if the divergence exceeds this value at any height in the VVP. Strong low-level divergence over the radar could be an indicator of a microburst. To properly set for microburst alerts, you must know the local characteristics of the phenomena.

Under Protected Areas for Warning Alert, select Protected Areas to see a list of areas.

The protected areas are configured in the setup utility. They are constrained to be rectangles with arbitrary size and orientation angle. There is a limit of 16 areas. (If you make a change to Setup, you must restart IRIS for the change to take effect.)

It is a good idea to make a large area (for example, 500 by 500 km (310.7 × 310.7 mi)) named ALL. When ALL is selected, the entire radar area out to 250 km (155.3 mi) range is a protected area.

Select TDWR Style to use the TDWR warning message format.

In TDWR format, only the strongest centroid in the highest priority area is reported along with its strength. For example: MBA 3MF 30K–, in spoken language: Microburst Alert, Three Mile Final, 30 Knot loss.

The older IRIS format reports all centroids in all protected areas, for example: 3 MBA warnings at 11:30 in: 3MF, 2MF. These messages are displayed at the bottom of the display screen and optionally spoken.

Select Say/Beep Warning to have the product generator to audibly signal the warning message in addition to displaying it as a message.

You must also select Enable Speech from the IRIS Setup menu.

Select Make Diagnostic for the product generator to create additional diagnostic output.

The diagnostic is a USER product type, with a USER data type, and the same name as the WARN product, except for a MSK.

You can display this product in the IRIS Radar Quick-Look Window.

This product contains the output of the initial thresholded input data. The LSB is the first input, bit 1 is the second, and bit 2 is the third. For a WARN of only one input, expect a binary file. You can use this to see the regions being processed.