It's been an unusually stormy May across the West with constant storms, but it looks like the pattern will start to change as we enter the final days of May.

In the meantime, though, there will continue to be a couple of storms moving around a deep trough that will be in place across the West through the Memorial Day weekend.

The first of the two storms will move through on Thursday with showers across much of the interior Southwest. The most widespread impact will be how cool it is.

Las Vegas will likely struggle once again to get out of the 60s, while Phoenix could be stuck in the 70s again.

The deep trough will continue to keep things on the cooler side through the weekend as another upper low moves in for Sunday and Monday.

The European model has been a little beefier with precipitation along the California coast from Sunday into Memorial Day, likely because it's showing a slower and stronger upper-level low. The GFS is a little faster and weaker, with not as much rain along the immediate coast.

Given how readily showers and thunderstorms have popped up over the last several storms, we expect showers to develop over at least the Sierra on Sunday. Depending on the strength and position of the upper low, a few showers and thunderstorms could develop over the Central Valley. There may even be some steadier rain for a time near the coast if the European solution verifies.

Rainfall amounts through the weekend will generally be under a half inch across the Central Valley and along much of the California coast. There will be higher amounts in the higher terrain, where some downpours and more persistent rain will set up.

Snow levels in the Sierra do seem a bit higher this time around, more toward 7,500 feet. There will be some snow on the ridges and perhaps even into a few of the highest passes, but there should be fewer travel issues than during other recent storms.

Once that Monday system scoots off to the east toward the Plains by the middle of next week, a ridge in the jet stream may finally be able to set up shop over the West.

Temperatures will start to bounce back closer to average as the ridge moves in. That will be most noticeable over the Desert Southwest, where afternoon highs will jump from the 70s and 80s through the Memorial Day weekend to the 90s by the final few days of May.

The Drought Monitor valid Thursday, May 16th, showing an area of moderate drought across western and northern Washington.

As this drier pattern gradually starts to take hold, we'll have to watch the Pacific Northwest. Wildfire season is fast approaching, and with an area of moderate drought showing up on the drought monitor across western Washington, this is going to become more of a concern.

Most fires in the Pacific Northwest are started by lightning, so we'll have to be on alert when thunderstorms develop (especially dry thunderstorms) in the high terrain of the Cascades and northern Washington as we get later into June and especially into July and August.

The drought and lack of rain recently could allow things to ramp up a little more quickly. I'll delve more into the Pacific Northwest wildfire threat in a future post in the next couple of weeks.

In the meantime, have a safe Memorial Day weekend!

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