NZUS96 KSGX 111332 LLLSGX CAZ043-048-050-055>058-060>062-065-552-554-120132- Public Information Statement National Weather Service San Diego CA 632 AM PDT Thu Apr 11 2024 To: Subscribers: -NOAA Weather Wire Service -Emergency Managers Weather Information Network -NOAAPort Other NWS Partners and NWS Employees From: Greg Schoor, Chief Marine, Tropical and Tsunami Services Branch Subject: Hurricane Threats and Impacts (HTI) Mosaic Testing on April 11, 2024 and April 25, 2024 The National Weather Service (NWS) Weather Forecast Offices (WFOs) in Honolulu, San Juan, San Diego, and Los Angeles along with WFOs in the NWS Southern Region west of the Mississippi River will commence with Hurricane Threats and Impacts (HTI) threat grid mosaic testing on Thursday, April 11. A second test that will include WFOs east of the Mississippi River is planned for April 25. Testing will begin at approximately 1500 UTC. Test activities will take approximately 1 hour; however, NWS dissemination systems may take up to an hour and a half to purge all test data. All test data is expected to be cleared by 1730 UTC. For the test, HTI grids will be created for hurricane Wind Threat, Storm Surge Threat, Flooding Rain Threat, and Tornado Threat at each participating WFO. Those grids are stitched together into storm-scale HTI graphics. The HTI Mosaic graphics are available in Keyhole Markup Language (KML) format on the following webpage: https://www.weather.gov/hti The mosaics are also available through the National Digital Forecast Database and on web pages hosted by the Weather Forecast Offices (WFOs) affected by the tropical cyclone. These webpages use the following URL format, where “wfo” should be replaced with the 3 digit identifier for the WFO of interest: NWS Southern and Western Region (San Diego and Los Angeles) WFOs: https://www.weather.gov/srh/tropical?office=wfo#hti WFO Honolulu: https://www.weather.gov/hfo/hti More details on HTI can be found in the Product Description Document: https://www.weather.gov/media/srh/tropical/PDD_HTI.pdf Periodic software and hardware testing in preparation for tropical cyclone events will continue during the remainder of 2024. For more information, please contact: Jessica Schauer National Tropical Services Program Manager Miami, FL Tropical.Program@noaa.gov National Public Information Statements are online at: https://www.weather.gov/notification/ NNNN