Public Information Statement
Issued by NWS Wilmington, NC

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NOUS42 KILM 081123

National Weather Service Wilmington NC
723 AM EDT Thu Apr 8 2021

To: Subscribers:
         -NOAA Weather Wire Service
         -Emergency Managers Weather Information Network
          Other NWS Partners and NWS Employees

From:    Allison Allen, Chief
Marine,  Tropical and Tsunami Services Branch

Subject: Hurricane Threats and Impacts (HTI) Mosaic Testing on
         April 8, 2021 (Backup April 22, 2021)

The NWS Weather Forecast Office (WFO) in Wilmington, NC and WFOs in
the NWS Eastern and in the Southern Region will commence with Hurricane
Threats and Impacts (HTI) threat grid mosaic testing on Thursday,
April 8.  Thursday, April 22 has been designated as the backup test
date in the event that testing cannot be conducted on April 8.

Testing will begin at approximately 1100 AM (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 130 PM (1730 UTC).

For the test, HTI grids will be created for Hurricane Wind Threat,
Hurricane Storm Surge Threat, Hurricane Flooding Rain Threat, and
Hurricane Tornado Threat.  These grids are sent to the National
Digital Forecast Database (NDFD) and can be seen on the NDFD web
viewer at:

The Product Description Document for these threat grids can be found

HTI grids are created by WFOs for their county warning area and
mosaicked together to form a more geographically consistent
depiction of the threat posed by hurricane hazards.  The HTI mosaics
can be found in kml format at:


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