Inland Northwest Hay Weather

In my last blog I mentioned a couple of things worth repeating: 1) there was no guarantee that we would see cooling by the weekend, and 2) there’s never been a 100F reading at Spokane Airport in September. Well, the computers are coming into better agreement on #1, and that could have implications on #2. First, let’s revisit the current weather map. Strong high pressure dominates the western coast of North America while a deep cool low pressure is giving the eastern US early fall weather.  What isn’t so obvious is that there’s actually a very minor low pressure disturbance over Oregon that will affect our weather.  Let’s look at a satellite image to see what I’m talking about. It’s actually made up of three circulations.  Rather complex, but also rather weak. They will very slowly move northward over the next few days, bringing with them a lot of clouds and moisture.  This is going to affect our weather in several ways.  The first is that we will see some gradua...

As I said in an earlier blog, on average the hottest time of the year in the Inland Northwest is the last week of July and the first week of August. But of course, averages are just that: averages.  A month ago it looked like this summer would hold true to form, with Deer Park airport hitting 99F on July 30th.  But it now looks like the traditional end of summer may be the hottest week.  The computers initially were focused on a hot weekend, with a gradual cooling after Monday (the 25th). But it now looks like 90s may prevail all next week. The culprit is of course, strong high pressure. Here’s the forecast weather map for Friday, courtesy of Tropical Tidbits.  I won’t bore you, but the weather maps for all next week look pretty similar. It’s not until the end of next week that we may see some relief from the heat, just in time for Labor Day weekend. But that’s not guaranteed.  With this kind of hot pattern, afternoon mountain thunderstorms will be a possibility...

If you woke up this (Thursday) morning, feeling like it was fall, you weren’t alone. Having fog and low clouds in early August is a rare treat. But don’t despair. Summer will make a reappearance by this weekend. But first, we have one last round of showers and thunderstorms this afternoon. Here is what one computer model thinks the radar will look like at 2pm this afternoon.  These showers and storms should move to the southeast, affecting the Spokane area by late in the day.  The next couple of mornings will be rather chilly, with lows in the lower to mid 40s.  Open the windows in the evening and see how cold you can get the indoor temperature. On today’s weather map below you can see the culprit of this latest rain, with a decent low pressure system over the  Northwest moving into the northern Rockies. But you can also see an area of high pressure developing off the coast of the PacNW. This trend will continue, so that by the end of the weekend, the weather map sho...

We have another potential opportunity for some rain later this week. But this will be very different from the rain last week. In that situation, the moisture was coming at us from the south, resulting in very muggy weather and heavy thunderstorms. In the case coming up, the storm is coming at us from the west. Typically this pattern in the summer yields very little if any rainfall for our side of the Cascades. But in this instance, the computer models beg to differ.  This is also not a good pattern for thunderstorms like we saw last week. First I’ll start off with the National Blend of Models (NBM). Remember, this is a blend of over 100 computer forecasts plus bias adjustment. It expects the rain to start Wednesday night and continue through Thursday. This pattern of rain looks pretty standard for this kind of storm and will probably verify the best.  But there are a few other ideas that the computers are throwing out, as usual.  First I’ll show you the US GFS model, zoom...