Inland Northwest Hay Weather

Some may not have noticed, but it’s been a very dry July.  Officially at the Spokane Airport, they haven’t measured anything more than a sprinkle. Has there ever been a July with no rain at all?  Technically it’s happened only once in Spokane, and that was way back in 1883.  There’s been 15 Julys like this year where only a sprinkle fell the entire month. The same happened in 2017, 2013, 2008 and 2003. To be fair, other locations in the Inland Northwest did receive rain. But mostly it was less than 0.10”. The exception was in the Colville area. I showed this chart a couple of years ago at the Northeast Washington Hay Growers meeting. The blue line is the July rainfall each year at Spokane, while the green line sort of a moving average. Between 1975 and 2000 there were several wet Julys.  But since that time, July rainfall has really fallen off to the point where it’s pretty much nonexistent.  In case you’re wondering, August shows the same thing. You may have no...

We have a few more days of heat before cooler weather arrives this weekend. Here’s the current weather map.  High pressure over the central US is nosing into the Northwest, giving us our current heat.  Kind of a strange pattern. There are two low pressure area of note in the map above.  One is off the California coast, while the other is way up north, west of Alaska.  These two will combine for a broad area of low pressure off the northwest coast, pushing the heat to our east by the weekend. As usual, the transition from heat to cooler weather will come with some related weather. Wednesday: hottest day of the week with temperatures 95-100. Thursday: Showers and thunderstorms are predicted to move through the area Thursday morning.  More showers and thunderstorms could develop over the northern mountains in the afternoon.  Precipitation amounts should be very light. Less than 0.10”.  A bit of a breeze in the late afternoon and through the night which wi...

Our monsoonal moisture surge is just about over, and it played out pretty close to expected. Lots of clouds early in the week, ending with stronger thunderstorms and showers toward the end of the event.  Here’s a map of the lightning strikes over the past 48 hours.  That’s a lot of lightning. Numerous wildfires have undoubtedly started. Time will tell how much of an issue they become.  Smoke was already an issue this morning.  The HRRR model expects this to continue tonight. Here’s its forecast: But by tomorrow night, the smoke plume should be pointed more into Montana.  We will cool down a bit for the weekend, but then the heat will return.  However, the moisture is not expected to make a reappearance.  Earlier computer forecasts predicted another moisture surge, but have since backed off of this idea. The result will be cooler nighttime temperatures. Instead of the balmy 60s we’ve had the past couple of nights, our lows will drop into the 50s and eve...

Things are getting hot and a little humid out there thanks to our southerly monsoonal flow. And they’re about to get a little wet. In the previous blog I mentioned a small stationary low off the Washington coast that was predicted to move across northwest Washington on Thursday. That is still the plan. And when it does, it will draw monsoon moisture into it, creating rain and thunderstorms, but mainly west of the Cascades.  But on Thursday night and Friday morning there could be a second impulse that could bring showers and storms to northeast Washington. Here’s the predicted rainfall for this event from the European model: You can see mostly light amounts of rainfall (less than 0.10”) for northeast Washington.  There’s an equal chance that we will see no rainfall or just sprinkles. This will knock our temperatures back a bit from the near 100F on Thursday. But it looks like we’ll stay in the 90s through the end of the month. We’ll also see some drier air, allowing our low tem...

Depending on your preferred weather app, you’ve probably seen something like this forecast for the next 10 days in Spokane from Accuweather: Yes, summer heat has arrived.  The last two weeks of July and the first two weeks of August are on average the peak of the summer heat season.  Here’s the current weather map: The dominant weather feature is a large high pressure center over the central US.  It set all-time records in eastern Montana on Sunday including 115F at Miles City.   The high is just a little too far east to bring triple digits to the Northwest. But there’s also a small low just off the Washington coast. We talked in the last blog about monsoon moisture paying a visit to our area this week.  For the most part this will be mountain thunderstorms.  Tuesday afternoon could see some storms over northeast Washington mountains.  But that small low is forecasted to move across northwest Washington mid-week, and when it does, that will be our best...

For those who have lived in the desert Southwest, you know that there is a wet season there. And it’s not in the winter. Here’s the average monthly rainfall for Tucson AZ.  The months of July, August and even early September are the wettest months.  Meanwhile, in the Inland Northwest, these are the driest months. The cause of the summer rains in the Southwest is known as the Southwest Monsoon.  A monsoon is defined as a seasonal shift in winds that cause a distinct change in the precipitation pattern.  In the Southwest, this change in wind direction is the result of persistent high pressure during the summer near the Four Corners area.  Air rotates around a high pressure center in a clockwise direction.  This acts to draw moisture up from Mexico into Arizona and New Mexico. Typically this moisture then rotates across southern Utah and into Colorado.  This is the “Frequent” pattern in the image below (courtesy of  https://opensnow.com/ ) Occasional...