Major Hurricane Maria Report 20 September, 2017 (1700Z)

This information is marked TLP White; Subject to standard copyright laws. TLP: White information may be distributed without restriction.

*Any reproduction or reposting of this content requires proper credit/attribution to NH-ISAC.

Meteorological Quick Look

      • Last radar image from the San Juan WSR-88D was received at 0950 UTC when Maria’s eye was located only about 5 n mi off the southeastern coast of Puerto Rico.
      • Subsequent 1-minute imagery from the GOES-16 satellite, as well as surface observations, indicate that the eye made landfall a little south of Yabucoa Harbor, Puerto Rico, around 1015 UTC.
      • Without radar velocity data, initial intensity is incredibly uncertain, best guess is 120 kts based on a typical inland decay rate.
      • Maria’s center is expected to move off the northern coast of Puerto Rico soon, and an Air Force Reserve reconnaissance aircraft is scheduled to intercept the center early this afternoon and provide a better estimate of how much Maria has weakened.
      • Initial motion is northwestward, or 305/10 kt. This northwestward motion is forecast to continue for the next 48 hours, followed by a turn toward the north by days 4 and 5.
      • The track guidance is tightly clustered and there were no significant changes made to the NHC forecast track.
      • Once Maria moves off the coast of Puerto Rico, it will take some time for the structure to reorganize over the warm waters of the Atlantic Ocean.
      • However, shear is expected to be less than 10 kts for the next 24-36 hours, and Maria has an opportunity to restrengthen a bit over that time-period. The NHC intensity forecast lies just above the intensity consensus through much of the forecast period.
      • Since we don’t have radar imagery from San Juan, and the eye has become cloud filled in satellite imagery, the hourly position updates are being discontinued.

 

Healthcare and Public Health Status

 

 Key Messaging

        • Maria’s core is moving over Puerto Rico, with life-threatening wind, storm surge, and rainfall impacts continuing over the island. Everyone in Puerto Rico should follow advice from local officials to avoid life-threatening flooding from storm surge and rainfall. A Hurricane Warning remains in effect for the Virgin Islands, but conditions should gradually improve there later today.
        • Wind speeds atop and on the windward sides of hills and mountains and on high-rise buildings could be much stronger than the near-surface winds indicated in this advisory.
        • A Hurricane Warning is also in effect for the northern coast of the Dominican Republic, the Turks and Caicos Islands and the southeastern Bahamas, where Maria is expected to bring dangerous wind, storm surge, and heavy rainfall.
        • Widespread damage is expected. Healthcare and Public Health needs are expected to be great. Government Agency and NGO’s are staging and ready to assist.