Inland Northwest Hay Weather

We're getting November-like weather during this last week of September.  Decidedly unusual.  Autumn has definitely had an early start this year.  And if you're like me, you probably still have outdoor work you want to get done before it gets cold and wet.  So are there any dry days in the near future?  Actually, yes there are.  As we said in the previous blog, after a stormy week this week, the pattern should change to drier and warmer next week.  But things may be changing a bit in the forecast. For today, we have our wet Wednesday system that we were talking about.  The radar right now looks pretty wet this morning.  This will be followed by afternoon showers. Here's the weather pattern causing all of this wet weather.  A deep area of cold low pressure over the Pacific NW. Thursday will see mostly afternoon convective showers.  The morning should be dry, but with a low damp overcast cloud deck. Friday is a little more iffy.  ...

 As we've been talking about in recent blogs, the weather pattern is becoming rather fall-like in a hurry.  Suffice to say, while September can be rather sunny and warm in the Inland NW, the 2023 version is not one of those.  And we're looking at a rather stormy week next week.  Rainy fronts every 24 hours or so followed by breezy winds. Sunday: The first member of the parade will be rather weak, typical for this time of year.  Most folks will just get a sprinkle during the morning, although a few could get a decent short rain.  Here's what one computer thinks the radar will look like Sunday morning. The rain won't last long and Sunday afternoon should be mostly dry.  But the next storm will be quickly on its heels.  Again, a computer forecast of the radar for sunset Sunday. Monday: While the forecast above looks rather ominous, there's still a lot of disagreement on what happens to this storm.  About half of the computer forecasts bring rain...

After a couple of dry cold fronts over the past few days, we are going to get some rain from the next weather system.  The difference is that this storm will center itself right over eastern Washington on Wednesday.  You can see the center of the low on the anomaly chart below. Winds rotate around a low in a counter-clockwise direction.  So instead of the Cascades providing their usual rain shadow (if the wind was from the west), in this case they don't play that role because the wind will be coming from the east and north. A cold upper low like that should also create an unstable atmosphere.  Showers and a few thunderstorms will spiral around the low center on Wednesday.  Here's what one computer model thinks the radar will look like on Wednesday afternoon. All of this activity will slowly drift to the southeast, exiting the Inland NW on Thursday.  The computers all differ on the exact amounts of rainfall they expect, which is normal.  They generally ...

Of all the seasons, autumn is typically the quietest when it comes to weather.  Winter has lots of strong storms in the jet stream.  Spring and summer are more unstable, creating thunderstorms.  But autumn typically has none of that.  The atmosphere is stabilizing (surface is cooling while the levels aloft remain warm).  And the jet stream is just starting to strengthen again.  Also, the temperature contrasts over different areas aren't very extreme yet, so weather fronts tend to be weaker. We've seen a few weak fronts pass by our area recently.  Most just bring some clouds, maybe a sprinkle or light shower, and perhaps a little breeze.  But overall, the first half of September has been rather quiet.  The weather computer forecasts are indicating a trend towards cooler and wetter weather for the second half of the month. Here's what the weather pattern looked like last weekend.  Warm high pressure over the western US with cool weather sy...

Now that the calendar has turned to September, it's time to take a look back and assess the summer.  First, we'll start with temperatures.  For the June-August period (also known as meteorological summer), temperatures in the Northwest were actually Much Above normal.  This kinda surprised me a bit, because it didn't really seem like a "hot" summer (we did have a few triple-digit days in August).  Elsewhere in the lower 48, parts of New Mexico, south Texas, Louisiana, Mississippi and Florida had their hottest summer on record (going back to 1895).  You may recall that Arizona was also extremely hot in July.  But their June was actually cooler than normal, so that helped to balance out the average. So how did the folks at the Climate Prediction Center do with their summer outlook?  Here was what they were saying back in May for the Jun-Aug outlook.  Overall, they had the right idea, that the biggest anomalies would be found in New Mexico, stretchin...