Watering In March

Yesterday, as temperatures surged into the lower 70s, I observed someone in my neighborhood watering their lawn.   So even with all the warm weather, should we be worried that our soil is already drying out?

But first, take a look at the amazingly warm temperatures on Thursday and keep in mind the average high on that date in Seattle is 55F!

 

Lots of 70s in western Washington and Oregon and 60s to the coast.

Although we have been MUCH warmer than normal, the precipitation has been close to normal for much of the winter.  Here is the % of normal for the last 30 days over Washington.  Wetter than normal over Puget Sound and MUCH wetter than normal over the NE Olympics and around Yakima.  A bit drier than normal in some other locations...but not by much.  No drought in Washington State.

So water is reaching the ground.  Warmer temperatures and more sun could mean more evaporation, but that is probably a small effect this time of the year.  But what does the U.S. drought center say?  

For example, they have a Crop Moisture Index (see below)...and that suggests that soils west of the Cascade crest are relatively moist (dark green).

The Palmer Drought Inde, which is more of a measure of long-term drought, is also wet over western Washington, but California is quite dry.

And it looks like we will receive enough moisture to keep the ground wet for a while.  Here is the forecast precipitation total for the next 72 hrs.  The Olympics and north Cascades will get plenty of water and southern BC will get hit fairly hard.

 My own personal experience is that here in Seattle one doesn't have to start watering until late May in dry years and late June in wet years.

So if you want dry, head to Yakima, eastern Oregon, or south.   And don't water your grass now....it doesn't need it.