April has been a record warm month here in the lowlands; as of tonight it’s the warmest April on record in Portland. That, plus a warm end to March, means the snowpack is melting earlier/faster than normal again this spring. Take a look at the numbers from the SNOTEL sites operated by the NRCS:
The faster melt means reservoirs fill quickly of course, but it also means less water in the streams in the late spring and early summer. A warm/dry May would definitely cause a few issues, but even just a few weeks of cool/wet would be extremely helpful. We’ll see how things go. Speaking of snowpack, I love this pic sent in by an anonymous photographer:
It’s the Cascade Lakes Scenic Byway just beyond Mt. Bachelor a few weeks before it opened LAST spring.
We have warm spell #3 of this spring coming up starting on Sunday. You can see it on the GFS meteogram from this 00z run this evening:
Also note the very dry weather for late April and early May. I love this chart that shows the last 3.5 days of GFS runs and their respective precipitation forecasts:
The latest run is on the bottom, from left to right. The run 6 hours ago is the 2nd line up, and you continue back in time through previous runs as you go up. Notice how dry the model is showing us for the next 10 days. Almost time to start watering this year already!
Chief Meteorologist Mark Nelsen