Monday, July 15, 2019

A wet week during the driest time of the year

We are now entering the climatologically driest time of the year for our region, a period when it is not unusual to get no precipitation for weeks.

But not this year.  It is now raining in parts of our region and that is just a preamble to the rainy period in front of us. 

To put it a different way, more JAWS (July Abnormally Wet Systems) will be making landfall on our coast.

Just to give you some perspective, here is the annual climatology of precipitation at Sea Tac Airport--specifically, the probability of getting .01 inches in a day.  During the next few days it will drop to around 10% ..or even a bit lower.  July 29th is typically  the driest day of the year, so if you are planning an outdoor activity (like a wedding or barbecue), THAT is best day to do so. (I know this is short notice if you were planning to tie the knot)


But our golden end of July won't be so golden this  year.    Rain moved in this morning, mainly south of Seattle, as evident from the weather radar, and some of it is heavy.

Weather radar image at 7:30AM Monday

And this is just the start.  Let me show you the predicted 24-h precipitation total during the next week.

The 24-h ending ending 5 PM today (Monday)-- rain over the coast, with light stuff from Seattle south.


The next 24h (ending 5 PM Tuesday) shows light stuff over western WA, but more  more over Idaho and Alberta.


Now you need the JAWS music.  Below is the 24-h ending 5 PM Wednesday, showing moderate rain hitting BC and northwest Washington.   Nice wetting over the Olympics and north Cascades.


And on Thursday, the heavier stuff moved down the Cascades to Portland.


And even more rain over BC and NW Washington on Friday.


 Now you really want to be impressed?  Here is the total accumulation through 5 PM Saturday. British Columbia will be soggy with substantial rainfall in the mountains, and western WA, particularly in the mountains, will get enough to wet things down.  Puget Sound will be a bit rainshadowed by the Olympics.


The implications of all this?   The wildfire threat in British Columbia has been low and will remain low.   There is a good chance we will escape the BC smoke this summer, which was the main source of our smoke last year.  The clouds and rain will make our wildfire season shorter and of less intensity.  It will reduce our water use and help bring up our streams, particularly in areas in which they have been low (like the Olympic Peninsula).   With this precipitation, our July totals will much higher than normal for virtually the whole region.

The latest extended forecasts (e.g., the NOAA/NWS CFSv2) do NOT indicate an unusually dry August (see below).  The bottom line:  after all the scary talk about a dry summer with catastrophic wildfires, it is becoming clear that such an apocalyptic scenario is becoming highly unlikely and you can enjoy the sunny days ahead without worry or concern.



24 comments:

  1. So, Cliff...is the solar marauder minimum going to affect our weather at some point? Will we move into a cooler period overall? I'm a little confused about this - other than the suns low solar activity.

    thank you

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    1. Fun trolling. You realize it was 90 in Anchorage last week right? Or do they use a different sun?

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    2. I too would very much like to hear your take on the effects of solar minimums on global temperatures and weather patterns. If its something that your up to taking on in a future blog, I'd very much appreciate your insight and scientific perspective and opinion. Thank you in advance

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  2. Hi Cliff, what is your thoughts on the weather.com model? Its showing a solid ridge moving into place by 7/21 with our infamous sun, no cloud everyday post 7/21. Before that only 60% of showers on Wed but nothing significant. I know you have spoken highly of this proprietary model in past blog posts.

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  3. Cliff, I really enjoyed your video with commentary. The NWS text forecast discussions which I've been reading for years are okay but lack your simplified and more detailed model explanation for lay people. For example I did not know that "cin" on precip maps means hundredths of an inch.

    Here's to more JAWS weather the rest of this month and into August/September. I don't care for the recent trend of drier, warmer summers.

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  4. wildfire in Mattawa WA, Grant Co. https://www.krem.com/mobile/article/news/local/wildfire/motorcycle-likely-sparked-5000-acre-powerline-fire-near-mattawa/293-f9a894b9-a15a-4378-8995-0d1e1f1d5feb
    Guess they don't read Cliff's blog about how astonishingly wet it is this summer.

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    1. A 5,000 acre wildlife is almost not worth mentioning. Last year there were hundreds of thousands of acres burning in the PNW in June! As a paint contractor and former student of Cliff's I am eternally grateful for his insights and honesty when discussing the forecast or unpopular issues such as ethics and the politicization of climate science.

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    2. Wet is a relative term and as you can see on Cliff's maps, not the same everywhere. Here in E. WA we are having a "wetter" July but in most places - except for brief deluges in thunderstorms - we get a sprinkling or at the most a hundredth of an inch. Fuels, especially cheat grass which has spread all over the intermountain west, still dry out. And with the winds, a spark causes a fast spreading fire. Due to the wetter conditions, especially in the higher elevations and BC we are in better shape than we were last year with regard to catastrophic wildfires, but fire still happens.

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  5. Nice to see our dangers from a warm and dry spring might be washed away with a wet July.

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  6. Wildfire right now on Grant county. Let's hope Cliff's prediction of major rain is right. PS Please send some to Whatcom County. We've just dug a 3' deep trench and it's bone dry despite all the rain that's fallen... Somewhere else.

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  7. I've got a multi-day driving trip planned the first week in August that will take me to Bend, OR and then on to Crater Lake and then farther south to Lassen Volcanic Nat'l Park in northern California. Was planning on doing this trip last summer but cancelled it on account of choking smoke. At this point, would you say southern Oregon and extreme northern California look like safe bets for minimal smoke in August?

    By the way, loved the chart of probability of .01" of precipitation for each day of the year.

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  8. I am SO tired of this rainy weather. Cliff, is there any chance we'll get some sun soon? Please? I usually barely survive January and February based on the hope that July and August will be warm and sunny with our normal, long, warm evenings. But now? Might be time to consider relocating! I almost miss the smoke....

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  9. WHAT sunny days ahead? All 3 or 4 of them? Ghawdz, I loathe this weather pattern. Not your (or any weather persons' fault, I know. *punches this stinkin' pattern in its center* UUUGH.

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  10. ". . . and you can enjoy the sunny days ahead without worry or concern."

    Cliff, your closing line is my favorite! Thanks so much for including it. I want to feel that I've had a good summer before fall arrives.

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  11. Sorry if this is a dumb question, but what unit is being used in the precipitation charts? What is c in? Cubic inches? How does one convert this to inches of rain?

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    1. The unit is hundredths of an inch. To convert, you will need a basic understanding of fractions. Godspeed.

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  12. Want some sun, go to eastern Washington. Two friends and I went and climbed in the Entiat mountains, and both Saturday and Sunday were mostly sunny.

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  13. Where can I find accurate monthly & year-to-date rain fall totals for various places around our area?

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    1. Here is an easy to view set of graphical pages from the NWS:

      https://www.wrh.noaa.gov/climate/yeardisp.php?wfo=sew&stn=KSEA&submit=Yearly+Charts

      If you play around, you will find monthly charts and more detail temp and precip charts.

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  14. Loving, loving this weather! After so many hot, hot summers finally a cooler, wetter one! And I'm already counting down the weeks until we pass out of scorcher territory (about another 8 weeks). I'm not letting my guard down though. Last year the misery cranked up in August.

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  15. Begreen - "cin" is an abbreviation for "centiinch", ie, 1/100th of an inch.

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  16. anybody what to lay odds on the switch coming on monday?

    http://wxmaps.org/fcst.php

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  17. The 29.78" barometric pressure I measured in NW Bellingham today is one of the lowest such July measurements I've observed in years.

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