Copy to New Event - SV.W to MA.W

Purpose:

This jobsheet will guide forecasters how to copy the Hazard Service event metadata for an issued Severe Thunderstorm Warning and use it to create a Special Marine Warning for valid water areas.

Tasks:

AT-A-GLANCE:

  • What? Special Marine Warnings (MA.W) are a type of marine product for short-fused and non-scheduled events. Severe Thunderstorm Warnings (SV.W) are similar to MA.W in that they are short-fused hazard events. SV.W are issued for a thunderstorm producing ≥ 50 kt winds and/or quarter-sized (≥ 1.00 inch) hail, while MA.W should be issued when a storm produces sustained or frequent gusts of ≥ 34 kt and/or hail ≥ 0.75 inches and/or waterspouts. Full technical details are available in NWS directives 10–313 for Special Marine Warnings and 10–511 for WFO Severe Weather Products.

  • Why? Hazard Services creates metadata for each hazard, which may be shared with other product types. As an example, this feature can be used to transfer metadata from a Severe Thunderstorm Warning to a Special Marine Warning. Instead of creating a new polygon from scratch, as was the case with WarnGen, the metadata can be used to create a polygon with information from the SV.W hazard event.

  • Considerations. While the Copy to New Event option is helpful in more expedient hazard creation, there are some things to be aware of. The fields that are copied over are the storm motion/bearing, storm track, and report sources/details. Most other fields will need to be adjusted after copying over the hazard metadata.

  • Required Coastal Extensions. The coastal geometries used in AWIPS and Hazard Services may present challenges or situations where invalid geometries prevent hazard product issuance. Coastal extension zones reduce the likelihood that complex coastal geometries interfere with Hazard Services performance. Coastal WFOs should have coastal extension area localizations already with WarnGen. These localizations will need to be transferred to the Hazard Services localizations by a Hazard Services focal point using this jobsheet.

 Follow the steps below for more detailed guidance.

  1. This exercise will use Hazard Services Storm Track Tool in the D2D Perspective. We will use this tool to first create a SV.W that intersects a water body boundary. Click on the icon with the red tornado and H to open Hazard Services and the Storm Track Tool.

  2. In this exercise we are going to use the One Storm option in the Storm Track Tool Dialog, though the same steps apply for the Line of Storms option. Make sure the Hazard Type is Severe Thunderstorm Warning – (SV.W) in the drop down menu.


     

  3. Drag the storm track dot to the location of the hazard and go through the procedure of tracking a storm with the Storm Track Tool. Ensure that the polygon extends out from land into a marine zone.

  4. Once satisfied with the polygon and details of the Severe Thunderstorm Warning, select the Update hazard hatched area checkbox in the Geometry section of the HID. Click Preview..., review the text of the warning, and select Issue (1) to issue the warning.
    NOTE: The Copy to New Event process also works with events in pending or proposed status.


     

  5. You will notice the SV.W polygon snapped to the extent of the coastal extension zone.


     

  6. Once the SV.W has been issued, go to the Console and right click on the hazard. A drop-down menu should appear with the option Copy to New Event.


     

  7. The HID will change to give you options to start a new Short Fuse event. In the Type menu select Special Marine Warning (MA.W).


     

  8. If you had modified the default polygon generated in step 4, you will not have a polygon extended area past the coastal extension zone. You will need to click Track under the Geometry widget. The tracking information from the SV.W should have carried over to this new event and a default polygon for the MA.W hazard type will be generated.


     

  9. Adjust the new MA.W polygon to match the SV.W polygon. Do note the duration time of the MA.W differs from that of the SV.W. You can adjust this to your desired duration.


     

  10. Fill out the Details section in the HID to match the expected hazards in the SV.W. When you select Update the hazard hatched area, you will notice an overlap of the two polygons at the coastal extension zone. Preview and issue the MA.W.

Congratulations, you've learned how to use the Copy to New Event functionality to generate a Special Marine Warning from a Severe Thunderstorm Warning!