Meteorological Fall starts today.  As stated previously, it looks like the 1st half of September will be mostly dry & relatively warm.  That said, a short heat-up is targeted for this week.  Grab your Mug - it’s time.

A morning marine cloud deck is well established across much of the west side of the Cascades, as Labor Day gets started.  The sun will burn the layer off, for a pleasant afternoon.  Tomorrow & Wed are going to be HOT, with temps in the 90s in many locations; upper 80s around the Puget Sound.  Temps should cool down a few degrees late week, as an onshore flow begins to return, so too will be a few thunderstorms along the OR Cascades. Fire risk will jump up.

This weekend - Sep 6,7 - is looking so so.  No consistent pattern on the charts.  The computers haven’t solved for the position of a Low off the coast AND just how much moisture may train north from a Pacific tropical storm charting to move near to or over portions of ’The Baja”.   An upper air flow pattern may drive monsoonal moisture northward, impacting the eastern basins of the PNW and setting off thunderstorms this weekend.  West side locations should not be damp, but we would not rule that out just yet.  Temps will be comfortable.

Week of Sep 8-12 continues to trend partly cloudy by Tue or Wed, with chance for a shower - primarily over the Sound - from a weak trough (Low) dropping in from the BC coast.  Warming late week, offering a decent pattern during the 4 day run of the 60th Mt Angel Oktoberfest. then warming up late week on into the weekend of Sep 13,14.

Week of Sep 15-19:  Dry with temps in the 80s in most locations; warmer in southern OR / eastern basins.  

Ponder Point - early indications of a general pattern shift late that week, with a strong ‘jet stream’ developing to drive Pacific storms into the PNW after the 20th or 21st.  Again, just a consideration.

Let the last Summer holiday begin.  Here’s the holiday outlook and what may happen through early September 2025.  ☕️ Ready?

Labor Day Holiday:  Delightful conditions!  An organized Low pressure ‘cell’ is off the PNW coast and is modeled to essentially ‘park’ there through the long weekend.  This helps to cool down afternoon highs into the 80s in most locations, along with holding off any rain or showers.  Excellent conditions for all outdoor activities.

Next week will yield another HEAT UP around the region, with Tue being the cooler day of the week.  Temps will broadly pop back up into the 90s Wed & Thu, Sep 2,3. Fri the 4th should be a few degrees cooler with an onshore flow increasing.  

Sep 5,6 weekend is trending dry & mild, with temps holding in a pleasant range, given an onshore flow.  Late Sunday afternoon, Sep 7, a weak cold front is charting to drop south along the BC coast, bringing with it clouds, chance for showers and notably cooler temps for a couple of days.  Most of the risk for precip should remain over the Puget Sound region; some cloudiness is likely on Monday the 8th elsewhere.  Note that this system will spark quite a decent “fall storm” over ID, MT & WY.

Week of Sep 8-12 is trending dry & warmer for Tue & Wed, then another cold front is charting to drop in, much like the previous one, threatening some rain & showers overnight Wed the 10th & Thu over Vancouver Is and the Sound; lots of clouds elsewhere south to Portland, maybe Salem.  The Mt Angel Oktoberfest starts on 9/11. 

Weekend of Sep 13,14 looks dry and mild, with an onshore flow that may be strong enough to keep a morning marine cloud deck overhead during the morning hours. The Mt Angel Oktoberfest continues through Sunday the 14th.

Bottom line: the first half of September is likely to remain dry - other than a few showers over the far NW area of WA and southern BC - with seasonally mild temperatures.  Nationally, there are no hurricanes threats indicated on long-range wx charts through mid-month.

Wow, it’s already the last week of the month and, for some, the final week of summer vacation.  HOT conditions will slowly cool as this week progresses.  We may have caught a “wx break” during the upcoming US holiday weekend; read on for details.  

Wrap around moisture from a Low centered over the CA-OR-NV border is training cloudiness over portions of the PNW this morning.  The are some thunderstorms associated with this pattern, so stay alert (east Eugene/Springfield getting hit as this is written).  Similar to the past few days, clouds may clear away somewhat by the afternoon, allowing the heat to build rapidly.  For all regions, temps in the upper 80s to 90s are possible for many locations today & Tue.  Somewhat cooler on Wed and another drop in temps by Thu/Fri.  Think low 80s.

Labor Day Holiday:  a favorable trend on the wx charts suggests the expected wet pattern may not develop - or be delayed enough for Patrons to sneak in a few pleasant days for outdoor activities.  Right now, some precip is possible, but quite spotty.  (Often model outlooks do shift back to earlier solutions, so keep that in mind.)  Overall, temperatures will moderate into ‘comfortable’ for most locations.  Higher humidity will help with fire fighting.

Next week - Sep 2-5 is trending rather pleasant in the temp department, as the ‘heat dome’ will shift over ID, with limited threat for precip.  Again, higher humidity will help with fire fighting.

The weekend of Sep 6,7 is looking WET for southern BC, as cold air to the north clashes with warm air over northern WA.  This is a new feature, so expect some modification going forward.  Warmer over the rest of the PNW (mid-to-upper 80s), as compared to the 'short week' after Labor Day.

HEAT may return again (not unusual for this time of year) in the Sep 9-10 period.  

Overall, we just don’t see any significant rainfall during the next 2 weeks, unless one gets caught under a thunderstorm.

The weather charts are showing a range of conditions over the next couple of weeks, with the timing of precipitation unfortunate.  ☕️ Mug time.

• ⚠️This weekend, Aug 23,24:  HOT.  Temps in the mid-to-upper 90s - even a few 100+ degree readings - in many locations around the PNW; NW WA & BC will be a bit cooler, however upper 90s remains probable away from the Sound shoreline.  Regionally, a DRY AIR MASS, so fire danger will be elevated.  Overnight low temps in the 60s, even 70s in a few locations.  Fan Up.
• ⚠️Next week, Aug 25-29:  HOT through at least Wed.  Some mid-level moisture may ‘ride north’ from the desert SW, setting off thunderstorms over the OR & eastern basins.  There are indications for an onshore flow to begin overnight Wed Aug 27, which would tap down the heat 7-10 degrees as the week ends.  It could be WET on Thu the 28th, esp north of Portland, as the first of a series of rain fields arrive.
• Labor Day Weekend, Aug 30-Sep 1:  While not totally resolved, models continue to suggest a cooler & DAMP holiday weekend, with systems moving onshore from the west.  We mentioned this last time and the solutions remain ‘wet’.  Not a total wash-out, but if verified, just about everywhere around the PNW will get cloudiness and moderate amounts of precipitation.  Labor Day itself may be the driest day of the holiday period.
• Post Labor Day week, Sep 2-5:  The short work & back-to-school week will likely start out cool and gradually warm throughout the 4 days.  
• Weekend of Sep 6,7: HOT again.  

🌀 Topical Tropical: Well, the latest tropical charts have dropped any hurricane threat for the US mainland through at least Sep 8.  FERNAND, if it develops, will spin out over the Atlantic as a fish storm.  Other tropical storm development is now being hindered by dry Saharan Dust.  Hopefully, this means we caught a break for now.  It is the peak of hurricane season, so we can expect future development.

For those that enjoy moderately hot, sunny August afternoons, this forecast will please.  Refill your morn’n Mug and get back here for the latest outlook for the rest of August.

Cool, onshore flow will keep afternoon highs a tad below normal for the next 2-3 days, then an extended warm period will develop, one that could hold through until Labor Day Weekend.

• This week, Aug 18-22: Afternoon sun after the morning marine cloud deck ‘burns off’.  Temps pleasantly in the 70s, maybe low 80s esp south & east regions. By Thu, the onshore will weaken & temps will begin to heat up into the 90s around western OR, SW WA; 80s around the Sound, north.
• The coming weekend, Aug 23,24: Mid 90s possible; high 80s north of Chehalis.  Morning sun.
• Week of Aug 25-29:  Onshore flow picks up, cooling the region down again, much like the current pattern.  This time, though, the pattern may shift to one that is like Fall, right in time for the extended US holiday.
• Labor Day Weekend, Aug 30-Sep 1:  The 'final holiday' of Summer.  Long-range charts hint of a Low pressure system drifting down the BC coast, ushering in clouds, cooler temps and showers throughout the entire holiday.  This is early, so don’t modify outdoor plans just yet.   Thunderstorms along the Cascades during Thu & Fri Aug 28,29.
• Post Labor Day week: trending cool, partly-to-mostly cloudy, but dry, as a Low centers itself right over the PNW.

It’s just about time for wine grape veraison - the important "coloring up” period for wine grapes — the transition from grape berry growth to berry ripening.  Veraison is often from late-Aug to early Sept, but timing can be quite variable because of summer weather conditions.  Any Patrons that are grape growers wishing to share whether or not veraison has started in your vineyard(s) — please post a note to rrufus@yahoo.com.