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Showing posts from June, 2025

The Start of Summer

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If you’ve seen the forecast, you’re probably thinking that summer starts on Monday (or has already started).  As we’ve said before, summer starts on the Fourth of July in the Inland Northwest. Yes, we will see some 90s for the first few days of this week as high pressure moves in from the Pacific.  But most of the time, these hot spells that move in from the Pacific are short-lived, and this will be one of those.  By the evening of the 3rd, the high pressure is well east of us, with cooler air moving in from the west. This will cool us back down into the 80s starting Thursday and continuing through the weekend.   But then, we’ll see the true start of summer.  Our old friend the 4-corners high will develop around the 8th.  See the Big H in the desert southwest? That is the indication that we usually look for to start the hot summer days.  More 90s than 80s. How about rainfall?  The first chance of rain will be around the 2nd or 3rd of July.  B...

Uncertain Fourth

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In the previous blog I mentioned that there was too much uncertainty in the computer forecasts to look very far into the future. Unfortunately that’s still the case.  I’ve shown the graph below on a previous occasion, but it can be a little confusing so I try not to mention it. So I’ll try to explain. There are three computer centers that produce multiple computer forecasts.  The US, the Canadian, and the European. All together they produce 100 computer forecasts. You can easily average them all together, but this can hide possible scenarios. So another way is to look for clusters of solutions. Below shows four possible scenarios for July 2nd. It doesn’t take a meteorologist to figure out that each one is different.  Some have the hot high pressure (orange color) over the Northwest.  This would bring hot and dry weather.  But the other two have the high pressure to our east.  This would mean a cooler forecast for us, along with a threat of showers. And each...

Weather After the Rain

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It took some patience, but eventually the rain fell in most places. It doesn’t make up for our dry spell, but it sure helped.  Here’s how much rain fell from the weekend storm.  Here’s a different view of the rainfall over the weekend.  It’s actually pretty close to the forecast graphics I was showing you last week.   So what can we expect for the next 10 days?  Kind of a temperature roller coaster.  After a showery Monday, we’ll warm up quickly on Tuesday, back into the lower to mid 80s.  A mostly dry cool front on Wednesday will bring some mountain showers, breezy winds and cooler temperatures.  We’ll be back in the 70s for Thursday and Friday with more mountain showers over northeast Washington. High pressure from the west will build into our area for the weekend, quickly sending temperatures climbing into the 80s, with 90s by Monday of next week. Beyond this things get more iffy.  There isn’t any clear cut agreement among the compute...

Weekend Rain Update #2

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We usually try to avoid looking for climate extremes in random date ranges, preferring to stick with looking at entire months or years. But I thought I’d violate that unwritten rule just to see how this spring compares to past years. So I looked for the number of days that were dry or only had a sprinkle during the last 30 days. I looked at Spokane data since it has a much longer history. Below are the results.  So in the past 30 days, Spokane has only had measurable rain on 2 of them. That puts this year second on the all-time list, just behind 1918.  It’s worth noting that 2021 is also near the top of the list, and 2023 is also in the top 20. Oddly enough, 2022 is on the other end of the list (not shown), with only 13 dry days in this period.  Suffice to say, we could use some rain.  And we’ll get some this weekend, but probably not as much as we want.  The latest computer forecasts continue to back off a bit on our forecast rainfall amounts.  The track o...

Weekend Rain Update

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Typically at this time of year, most of us are looking for some dry days to put up hay. But this year, rain will be a welcome sight. And it still looks like we will be blessed with some rain this weekend. So let’s look at some details.  First, the timing. It still appears that the rain could start as early as Friday evening, but is a guaranteed done deal by Saturday afternoon. Here’s the rain probability for Deer Park.  93% of the computers agree that it will be raining at 2pm on Saturday. It’s rare to get that much agreement on a forecast of rain, especially at this time of year.   You can see decent chances of rain throughout Sunday and even Monday as well before we dry out and warm up. But the extended forecast doesn’t look hot yet and may provide another chance of rain late next week.  How much rain will we get this weekend?  That is typically the toughest part of the forecast. First I’ll show you the National Blend of Models (NBM).  It expects the bulk...

Rain Likely This Weekend

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In the last blog we talked about the low that stalled off shore, and that it would wait until this weekend before moving onshore. Confidence of this scenario is increasing. The rain could start as early as Friday afternoon, but more likely it will hold off until Saturday, possibly as late as Saturday evening. Rain by Sunday is almost a sure thing. Here’s the chances of rain for the next 10 days.  From late Saturday through Sunday, confidence is getting high that it will rain.  It is worth noting that with our previous forecast rain event (that didn’t pan out), the percentage only went up to about 20%.  At this point, confidence for rain this weekend is up to over 60%. How much rain are we talking about?  This too has been increasing. Originally it only looked like about 0.10” would fall. But now it’s looking more like 0.25” to 0.50”. Here’s the expected accumulation at Deer Park.  The map below shows the expected rain accumulation for the weekend.  Its wort...

Are We in a Drought?

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The answer to the title of today’s blog is the dreaded “it depends”.  Depends on what?  On your definition of a drought. Let me explain.  In the West, we receive the vast majority of our precipitation in the winter and spring, with very little rainfall in the summer. Thus, nearly all agriculture in the West depends on irrigation, which is largely dependent on mountain snowpack. It doesn’t really matter when the snow falls in the mountains. As such, the West typically focuses on the amount of precipitation that falls over the entire wet season of November through May.  Below is a graph of the precipitation at Deer Park for this year (green) compared to normal (brown).  Starting in November, Deer Park airport has had above normal precipitation (green line is above the brown line).  At some points during the winter we’ve been 2 or more inches above normal.  But our recent dry streak has brought the green and brown lines together, meaning we’re right at no...

When Will it Rain?

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  Our transition from hot and dry to cool and wet sort of panned out. We got the cool, just not the wet. The much anticipated low pressure system stallled off the coast. Close enough to knock 20 degrees off our temperature from early in the week, but too far away to give us any rainfall.  Unfortunately, the low is going to sit offshore for about a week. It will wait for another Pacific low to “kick” it onshore around next Friday.   Until then, we’re going to see temperatures warm back into the lower 80s early next week, followed by a cool down with a chance of mountain showers on Wednesday.  Here’s what the European computers think the odds of rain are for Wednesday. Next week will also see continued breezy daytime winds along with dew points in the 40s.  Good for drying hay, but dew may be hard to come by, especially in the middle of next week. Here’s a summary of rain chances for the next 10 days.

Heat then Cool and Wet - Update 2

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The upcoming pattern change is still pretty much still on track with the forecast the computers have been advertising.  Monday will be the hottest day with daytime temperatures in the mid-90s.  Then we'll cool 4-5 degrees each day through the rest of the work week. One nice element this week for curing hay will be the breezy winds.  Each day should feature winds of about 10 mph (green shading in the image below) with gusts to 15 mph (yellow shading).  Nighttime winds should go calm for the next few nights which will allow humidities to climb high enough to form a light dew.  But by Wednesday night and Thursday night, there could be a light breeze all night in some locations which could hinder dew formation. The chances for rain are still hard to pin down.  This is in large part because this isn't a large frontal band of rain we're talking about.  It's more showery, and as such, hit or miss. The European models still point to Friday as the best day of w...

Heat then Cool and Wet - Update 1

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Not a lot of change in the forecast during the past 24 hours. First, the heat is still expected this weekend and early next week. Here is the probability (black line) of a high of 90F or higher for the next 10 days. Monday should be the hottest day with a nearly 100% chance of breaking 90F.  Then a gradual cool down over the rest of next week. The rain chances for Tuesday and Wednesday are looking even smaller than yesterday’s forecast.  The European computer puts the odds at less than 1 in 10. However, the US computer forecast actually has a 30% chance of rain during this period   The Canadian computer is somewhere in between the others.  But even the wetter US model says that any rainfall should be light , less than 0.10”. Chances for rain continue to slowly increase for the rest of the week and weekend. The graph below shows the chance of receiving specific amounts of rain in 24 hours. So for example, on Friday, there is a 23% chance of getting at least 0.01”...

Heat Followed by Cool and Wet

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In the last blog we discussed a gradual warm up this week followed by a cool down next week. That still looks like it will happen, pretty much on schedule. Let’s talk about some of the details.  Currently, high pressure is located to our west. This has caused our temperatures to warm a bit, but it also allows weak weather systems to pass by to the north of the high pressure and then drop down into our area.  We saw this the past two days, with clouds and a few sprinkles. But now the high pressure is on the move, and will be squarely over the Northwest this weekend and early next week. This will bring us our first 90 degree days on Sunday and Monday, and probably Tuesday.  But on the weather map above there is a small area of low pressure near Anchorage, Alaska.  This is going to develop into a much larger storm and head for the Pacific Northwest. Here’s the expected weather map for next Friday.  This is a cool and wet pattern for our area. And the computers expe...