Current direction info needed in Tidal Forecast display
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In exploring the Tide Forecast display option—where it shows tide AND current station information across all layers (note this is NOT the Currents or Tidal Currents layers)—I found that the current information lacks critical information for marine users: It does not include current direction—either ebb or flood—not does it provide the depth of the reading. (Or, if that information is there it is not easy or intuitive to find.)
I am a sea kayaker who paddles frequently in Puget Sound and this information is critical because it helps me determine whether conditions are safe for paddling (winds against a current build big steep waves quickly) as well as being able to plan trips and estimate the speed of travel, etc. Really, this information is important to all boaters.
The example I will use in in Dana Passage in the south end of Puget Sound.
As you can see, once I chose to display the Tide Forecast, tide and current stations are shown on the layers. Here they are showing the general status for the stations: Tide=L (low tide) and Current=S (slack) or E (ebbing) or F (flooding).
Looking at the information for Dana Passage we see the times the current hits peak flood and ebb as well as slack, along with the current speeds, but it doesn’t tell you what direction the current is flowing during either the ebb or the flood. And, in Puget Sound, as in many other coastal areas, this information is often counterintuitive as it is affected by a variety of local factors. It is critical a boater—especially those in hand-powered or sailing craft—understand what direction the current is flowing.
Next you will see the information in Windy mirrors the information included in NOAA’s page for the Dana Passage Current Station but doesn’t show the current directions. NOAA’s page does, using True North compass values (red oval).
But, you’ll also see that the information for both Windy and NOAA are drawn from readings made at a depth of 50 feet. Few boaters are concerned about current at these depths (although divers certainly would be).
The next NOAA image shows the current information for a depth of 16 feet—the shallowest provided for the station—and you’ll see that that times of the max flood and ebb have changed while the direction of the currents have changed slightly—so slightly as to be negligible for most boaters.
The timing changes are important to kayakers like me: It often means the difference of being able to paddle easily through a channel on the slack or fight an opposing current.
In sum, Windy needs to update the Tide Forecast display information to include information about current direction (critical) and, when given a choice on depth readings, choose the shallowest (less critical but it would be great).
Thank you
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The Tidal currents layer and the tide graph in the point forecast panel are both computed by global models with quite a large resolution. They are not able to do a precise calculation in some areas with bays, river mouths, estuaries or straits because the data resolution cannot take into account the shape of seashore and seabed.
In the area you mention, this data is probably wrong in some places.At Tide forecast POIs data comes from local tide gauge stations, and are probably more accurate.
In deep estuaries it is recommended to rely on local tide charts. For example if an inlet is constricted by a narrow pass, the maximum current in the pass may be offset relative to the tidal times within the pass and coincide with low tide in the pass.
