Are We in a Drought?

The answer to the title of today’s blog is the dreaded “it depends”.  Depends on what?  On your definition of a drought. Let me explain. 

In the West, we receive the vast majority of our precipitation in the winter and spring, with very little rainfall in the summer. Thus, nearly all agriculture in the West depends on irrigation, which is largely dependent on mountain snowpack. It doesn’t really matter when the snow falls in the mountains. As such, the West typically focuses on the amount of precipitation that falls over the entire wet season of November through May. 

Below is a graph of the precipitation at Deer Park for this year (green) compared to normal (brown). 


Starting in November, Deer Park airport has had above normal precipitation (green line is above the brown line).  At some points during the winter we’ve been 2 or more inches above normal.  But our recent dry streak has brought the green and brown lines together, meaning we’re right at normal for the water year.

Taking a look at at the entire Northwest, we can see that most areas are below normal for the year (red-ish colors), but some areas are above normal (blue and green colors)  


In the eastern and central US, where many crops are watered by rain, not irrigation, they look at drought differently.  A few weeks of dry weather in the summer can severely damage if not kill crops.  This is referred to as short-term drought, or in some cases, flash drought.

The US Department of Agriculture (USDA) updates their Drought Monitor weekly, with input from hydrologists and meteorologists from each state.  Here’s the current drought assessment for Washington state.


You can see that their assessment D0 (Abnormally Dry) over much of the state, with D1 (Moderate Drought) only in the Cascades and Blue Mountains.  So based on the USDA, the Inland Northwest is not currently in a drought.  Notice how this map closely mimics the Percentage of Normal precipitation for Washington that I showed above.

But we also know that not all crops in Washington are irrigated, including hay and grain.  Timely spring rains are crucial for these crops.  So let’s take a look at how things have been since April 1st.  First, we’ll generate the same graph for Deer Park as before.


Wow!  That paints a much bleaker picture than looking at the entire water year.  Yes, the winter moisture is important.  But the lack of spring rains is also crucial.

Here’s how the entire Northwest looks for this same period.



Large areas have received less than 50% of the normal rainfall this spring!

The USDA also monitors selected crops on a county-by-county basis and publishes their results  week.  Here is the latest analysis for Washington state.




According to this analysis for pasture across the state, conditions are largely Good to Excellent, although that number is trending downward. Note that we are far from this disastrous 2021 year.

So the answer to the original question is that we are possibly entering the beginning of a short-term or flash drought for non-irrigated crops.  This may be mitigated if we get the expected rain this weekend  






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