March 18, 2021

Will the Incoming Storm Take Out the Little Saildrone?

 As I mentioned in an earlier blog, NOAA is working with a young company, Saildrone, to test the capabilities of autonomous sailboats (saildrones) for gathering weather and ocean data remotely.

Of particular interest is whether such craft can survive the wave and wind conditions near tropical storms and hurricanes.    A hardened saildrone with a stubby sail is now directly off the Washington coast (see map and picture below) in the hope of experiencing strong storms.

And it is about to get a big test.

A vigorous spring Pacific cyclone is offshore and approaching our region, with the visible satellite image showing the swirl of clouds around the low center.

The forecast for sea level pressure and winds (dark blue indicates gusts of 50 knots and more) at 11 PM tonight shows a decent storm for March and very windy conditions offshore.  With a large ocean fetch and a slow-moving low center, substantial waves are possible.

The threat will increase overnight: let me show you some fancy graphics from the Saildrone website.

At midnight tonight, the little boat will be hit by strong southerly winds as the low center approaches from the southwest (dark red/black are the strongest with sustained winds of 40 knots and more)

But with the low center moving slowly, the poor saildrone is battered for hours by gale-force winds.  For example, here is the same plot for 8 AM Friday, showing the continuation of strong southerly flow

And let's not forgot the waves, which are the real threat to the saildrone.   Strong winds and a slow-moving system can lead to substantial wave heights.  The latest forecast of the NOAA Wave Watch 3 system predicts up to 10-meter waves (significant wave heights) reaching the boat (see the forecast for 4 AM Friday morning).

It will an exciting night at the saildrone offshore.  This will not be the equivalent to a direct hit of a hurricane but should serve as a useful test, since similar conditions disabled the earlier generation of saildrones with tall sails.  I will let you know what happens.



The Northwest Weather Workshop will be held on May 1, 2021 and everyone is invited.

Each year, local meteorologists and weather lovers get together to review the weather of the past year and to talk about Northwest weather.  This year the meeting will be held virtually and everyone can attend.

Information is here:

If you would like to give a talk, the deadline for titles and abstracts is April 10th.



  1. I've always wanted to photograph big storms/waves on the Olympic Coast, doubt I'll be able to make this one but would it be a good opportunity? How large will the waves actually be at, say, Third Beach?

  2. Tornado warning in Washington state I hear?

  3. So did 1054 survive the storm? Inquiring minds want to know...

  4. Did the saildrone survive the storm?

  5. Count me in as an inquiring mind also ... what was the fate of the little saildrone?

  6. Bonnie and others: the Saildrone has survived! Thanks for asking....cliff


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