NOAA's 2021 Saildrone Observations of Atlantic Hurricanes for Improvement of Intensity Forecasts

Improving the accuracy and ultimate value of  NOAA's operational hurricane forecasts requires more complete real-time knowledge of atmospheric and oceanic conditions and more realistic representation of key physical processes in hurricane forecast models. To meet these needs, a research team from NOAA's Pacific Marine Environmental Laboratory (PMEL) and Atlantic Oceanographic and Meteorological Laboratory (AOML) deployed five saildrones (see picture below) to observe conditions near the ocean surface during the 2021 Atlantic hurricane season.

Saildrone on the water

Saildrones are uncrewed surface vehicles powered by wind and solar energy and remotely piloted via satellite telecommunication. They measure solar irradiance, barometric pressure, air temperature, humidity, wind, waves, water temperature, salinity, chlorophyll, dissolved oxygen and ocean current. They can also measure surface short- and long-wave radiation. The five saildrone of this deployment are specially designed for hurricane observations.


(1) Measure near-surface atmospheric and upper-ocean parameters to calculate energy and momentum fluxes between the atmosphere and ocean outside and within hurricanes.

(2) Synchronize the deployments of saildrone and ocean gliders (see picture below) to measure the coupling between the surface atmosphere and upper ocean.

(3) Transmit data in real-time to operational weather prediction centers to improve atmosphere-ocean initial conditions in forecast models.

(4) Apply the observations to understand how air-sea interaction affects hurricane intensity and to advance hurricane prediction models.

Ocean glider taking measurements in the water

Ocean gliders are uncrewed underwater vehicles powered by batteries. They measure water temperature, salinity, and currents from the surface down to 1000 m. They send their observations to satellites when they are at the ocean surface. There will be approximately 20 glider missions operating during the 2021 hurricane season, several of them operating in areas where the saildrones will take observations in order to provide quasi-collocated simultaneous observations of the ocean and atmosphere.


Saildrone observations cover August 1-October 31, 2021 in five areas (highlighted by gray boxes in the map below) where chances of hurricane occurrence are high. Observations are sent to worldwide weather prediction centers in real time to assist their operational forecasts. 

Saildrone real-time positions and data can be viewed at any of the following three web pages: 
OceanViewer at AOML
Saildrone+Glider Time Series at AOML
Saildrone Data Access at PMEL 
Saildrone data visualization dashboard

This project also involves partnerships with NOAA's Environmental Modeling Center (EMC) of the National Weather Service and the CoastWatch of NOAA's National Environmental Satellite and Data Information Service (NESDIS).

Hurricane and tropical storm tracks and regions saildrone will take measurements in the Atlantic

The dark and light gray boxes highlight the areas where saildrones will operate during August-October 2021. Dark gray boxes are where saildrones will additionally coordinate with ocean gliders. Lines are tracks of past category 5 hurricanes (black), other hurricanes (grey), and tropical storms (white). The background colors represent the probability of tropical storm force winds during August-October, based on data from 2000-2019.

NOAA Mission Team:

Gregory Foltz, AOML (Co-Lead)
Chidong Zhang, PMEL (Co-Lead)
Andy Chiodi, PMEL/University of Washington
Calvin Mordy, PMEL/University of Washington
Christian Meinig, PMEL
Dongxiao Zhang, PMEL/University of Washington
Edward (Ned) Cokelet, PMEL
Eugene Burger, PMEL
Francis Bringas, AOML
Gostavo Goni, AOML
Kevin O'Brien, PMEL/University of Washington
Noah Lawrence-Slavas, PMEL
Joaquin Trinanes, AOML/University of Santiago, Spain
Jun Zhang, AOML/University of Miami


Catherine Edwards, University of Georgia
Shuyi Chen, Edoardo Mazza and Brandon Kerns, University of Washington
Xingchao Chen, The Penn State University

With support of

Maria Morales Caez, The Penn State University

This mission is supported by NOAA Ocean and Atmospheric Research (OAR) and Office of Marine and Aviation Operations (OMAO) in collaboration with Saildrone, Inc.  

Photos & Videos

2021 Saildrone Atlantic Hurricanes Mission (credit: Dr. Gregory Foltz, NOAA/AOML) on PMEL's SmugMug