Is This a Dry April?

In a previous blog I mentioned that April is sort of between the two wet seasons in the Inland Northwest.  So on average, April is drier than March and May. But this April seems a bit drier than normal. Is that true?

Well, the short answer is yes. Here’s a look at the percent of average precipitation across the lower 48 states for April thus far. Easy to see how the entire West has been drier than normal this month.


A closer view of the Northwest shows that only a small area from Tri Cities to Ritzville is running wetter than normal, thanks to our big rain event around the 7th. 




But memories are typically short. So most of us have probably forgotten the wet events in early April. Here’s the daily precipitation at Deer Park for April. The green line is the actual precipitation, while the brown line is the normal.  You can clearly see the wet event we had on the 7th, which took us briefly above normal. But since then, we’ve seen very little rainfall and we’re now more than 1/2” below normal. 


In Spokane, the situation is even drier. 


So how does this compare to historical Aprils? In the graph below, you can see that April of 2024 was drier than this April. And we’ll likely add to our total a bit on Tuesday (more on that in a minute). 2020 and 2021 were both drier still. So this isn’t a record dry April by any stretch.




What about April temperatures?  For daytime high temperatures, the Northwest has been warmer than normal. 



But our nighttime low temperatures have been cooler than normal. These are due to the dry air we’ve had in place most of the month. It gives us sunny warm days, but chilly nights. 


So, I mentioned rain on Tuesday. This isn’t a very wet storm, but the computers have been trending a bit wetter. The wetter computer forecast comes from the European model. As you know, it’s typically the most accurate, but it’s a little out on a limb by itself with this forecast. 


The US model is quite a bit drier. The Canadian and UK models are somewhere in between. 


Rain should start in the late night hours and end around noon on Tuesday. 

You can also see on the above graphic that there’s additional chances of rain as we turn the calendar to May.  The storm on Friday night and Saturday will approach us from the southwest. This means a better chance of rain in the Basin.  It also means a very warm day on Friday before the rain begins. Highs around 80. 

Lastly, if you’re looking for light winds this week, Wednesday and Thursday are your best bets. 



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