Wetand News

When one thinks of the Northwest during the summer, the word monsoon is not the first thing that comes to mind.  But during the last day, Southwest Monsoon moisture has spread from the southwest U.S. into our region. It has already rained at Sea-Tac Airport and clouds have spread over western Washington.   The water vapor channel of the NOAA GOES satellite clearly shows the plume of moisture heading directly over the Northwest. And the visible satellite image this morning highlights the associated clouds over western Washington and northern Oregon The radar image around 7AM indicates some showers moving up into our region.   My newspaper was a bit soggy this morning. This moist air will be around this weekend and the air is unstable enough for more showers this afternoon, particularly over and east of the Cascade crest. Over the 24h ending 5 AM Sunday, most of the showers will be over eastern Oregon (see 24-h accumulated rainfall below.  And some of these showers will be associated w

My podcast today will review the major shift in our weather that will occur this week.   And in the second segment, I will talk about Northwest thunderstorms. We start with a minor heatwave today with temperatures zooming to around 90F in western Washington away from the water and into the upper 90s in the Willamette Valley. But at the same time, a major plume of moisture will move northward into eastern Washington and Oregon, bringing thunderstorms (the image below shows the predicted rainfall through 5 PM Sunday). Wildfire smoke will move in overhead during the weekend but not reach the surface in western Washington, so you can breathe easily.  But the plot of total smoke above us on Sunday night is scary: Finally, there is the BIG change at the end of the week.  Clouds, precipitation, cooler temperatures.  Way earlier than normal.  The 48h total rain ending at 5 PM Friday is shockingly wet. My podcast will not only describe this forecast but give you an essential background regardin

Many of you will need umbrellas during the next week.   And perhaps a lightning rod.   The cause?  A dramatic plume of moisture will be heading into the Northwest from the south.   Southwest Monsoon moisture will be entering our region, and our chances of breaking any dry spell records are dimming fast. The latest water vapor satellite image shows the impressive moisture plume over the Southwest--- and it is heading our way. Let me start by showing you the latest precipitation forecasts from the UW WRF model.  For the 72 hours ending 5 PM Tuesday, the interior gets wetted down well, with some favored locations enjoying over an inch of rain.  This precipitation is from the plume of moisture from the southwest U.S.   But our wet bounty is not over: during the next 48 h the first Pacific disturbance of the season moves in from the west and provides precipitation for western Washington and southwest BC. This system is a bit earlier than normal (normally the first wet system occurs during

One can make a pretty compelling argument that July 2021 will go down in the record books as the most perfect weather month in western Washington history. Perfect in every way Moderate, but warm temperatures.  Cool enough at night for sleep.  Lots of sun. No wildfire smoke.  Good air quality.  No rain. Picture today over Puget Sound, courtesy of Ben Slivka Temperature: Consider Boeing Field in Seattle .  Every day has had maximum temperatures between 69 and 84F.    Never too cool or too hot! And enough variation to keep it interesting.  But wonderful for outdoor recreation. Cool enough to sleep at night?  You bet!     Every day at Boeing Field had low temperatures below 65F and most days dropped to around 60F or the upper 50s.  And that is in the middle of the urban heat island .  Most folks enjoyed even cooler nighttime minimum.    You could sleep well without AC! What about sticky conditions?  Humidity that can make life so unpleasant in much of the U.S.? Not here in western Washing

Every summer starting around mid-June and ending by the beginning of September, moisture streams northward out of the Gulf of California into Arizona, Nevada, and the eastern portions of the Pacific Northwest. Known as the Southwest Monsoon or the North American Monsoon, this phenomenon is associated with the river of moist unstable air that brings thunderstorms into the southwest U.S. and occasionally into eastern Oregon and Washington. This moist current, with an origin over the warm Gulf of Mexico, is the result of high pressure that develops during the summer over the Southwest U.S. When this high shifts to near the Four Corners area of the SW (where AZ, NM, CO, and UT meet), the moisture can surge into the eastern portion of the Pacific Northwest.  This should happen later this week. To see an example, lightning moved into eastern Oregon on July 20th (see below) This was associated with the Southwest Monsoon and the Four Corners high, bringing moisture in from the south and sout

 We are now in wildfire season and the resulting smoke is on everyone's mind.  And the dramatic transcontinental movement of West Coast smoke has gotten national attention. What controls the movement of wildfire smoke?   What conditions produce dense smoke in western Washington and Oregon?   How can smoke pass above us aloft, but our air quality remains good? All of these questions will be answered in my new podcast. And I start the podcast with the weather forecast, with our weather being near perfection in western Washington if you like clean air, sunny skies, no rain, and temperatures around 80F. To hear the full story, listen to my podcast below or select your preferred streaming service    

Whether one calls it an artful statistical sleight of hand or poor scientific communication, several non-peer-reviewed climate attribution reports have provided misleading information that poorly informs society. > previous blog . In their problematic approach, they get HUGE, unrealistic changes in the odds of extreme events, with their identified events going from once in thousands of years to every year or every five years.  But their" findings" are the result of problematic models, careful selection and definition of extreme events, and deficient statistics. For the dam situation noted above, their model situations, even with their deficiencies, would indicate that global warming would produce a huge increase of probability of getting to 24 ft, but a far lesser influence on water getting to the critical 18 feet.   The selection of the threshold used for the analysis has a huge impact on the results. The bottom line Many of the climate attribution studies are resulting

 A remarkable situation is evident right now.   Fires over the western U.S. are producing a dense veil of smoke that moved across the continent and then descended over the East Coast. And there is a great irony in all this: most of the West Coast has excellent air quality while the air is unhealthy over the northeast U.S. To illustrate this strange situation, here is the latest AIRNOW air quality map showing the air quality based on PM2.5, small particles that can move deep into your lungs.  ( I want to acknowledge UW Bothell professor Dan Jaffe, who brought this to my attention) Green is good air quality while red is unhealthy.  Really bad air quality in parts of New York, New Jersey, and Pennsylvania.  But air quality is really good along the West Coast! You can visualize the movement of smoke by an image showing the smoke distribution at 11 AM this morning from the wonderful NOAA HRRR model.  Smoke generated over eastern Oregon, northern CA, and eastern WA moved northward around a r