HOW TO PREDICT THE TIDES
While you can view some of the low tide critters during tides as high as +2 feet, it is best to go during a negative tide, or a tide that is lower than 0 feet.
There are a few resources to help you determine when a low tide will occur.
For long term forecasting, the National Oceanic and Atmospheric Administration is best. Visit their tide prediction website, input your desired location and it will provide a downloadable PDF document of tide predictions for the year. The more accurate you can be with location the better.
The tide tables are fairly simple to decipher. They provide a calendar that details the time and depth for high and low tide for every day of the year. Look for anything below 0 feet for a sufficiently low tide.
If your low tide walk is coming up within the next week, apps such as Tides App by Tides Chart are very useful. They provide more accurate timing and depth information closer to the date but do not provide data for further away dates. Tides Appis also handy if you happen to find yourself near a beach and want to know when might be best for tide pool viewing.
It is best to arrive at least an hour before the lowest tide of the day occurs. The lower the tide, the earlier you can arrive and see exposed organisms. Depending on your location, tides can return rapidly after reaching their lowest point. Be aware of the rising tide and ensure you have a route to safety for when the tide returns.
There are many places in the Seattle area where tide pools and marine organisms are exposed during low tide. If you wish to have a guided experience, check out the Seattle Aquarium Beach Naturalist program which places trained volunteers at locations throughout the city during low tides.
If you a different coastal area, check your local aquarium to see if there is a similar program. Sometimes nearby education institutions, state parks and natural areas will host similar events or classes. Be mindful that the activity of tide pooling may be called something different in your area. In the United Kingdom it is referred to as rockpooling!
This is an example of a tide prediction chart for Bowman Bay, located in Deception Pass State Park in Washington State.
Looking at the chart I would determine that March 14 & 15th were my only good opportunities for a low tide adventure in the daylight.
There are also substantial low tides January 8th- Jan 13th and February 6th- 10th. While the low tides all occur in the dark, with proper preparation and the appropriate site I would be able to come up with a good low tide adventure.
On Tides App you can get a view of the day and it also interprets it in plain text "The tide is currently rising in White Center. As you can see on the tide chart, the highest tide of 10.83ft will be at 8:19pm and the lowest tide of 1.97ft was at 2:26am."