Stormy Weekend Ahead; 3 Storms

Is it November or is it the last weekend of September?  The weather maps say November!   We have one wet front coming through the Pacific Northwest tomorrow, then a much stronger (wetter and windier) storm forecast to move through the Pacific Northwest Saturday afternoon through Sunday morning.  A possible 3rd system could arrive Sunday evening.

Forecast models have come into very good agreement on what the ECMWF model started showing 2 or 3 days ago…an unusually wet and windy system for the last few days of September.

The Highlights

  1. Rain arrives by noon at the latest Friday…then it’ll be wet from that point through the weekend.  It’s an “indoor weekend”.
  2. Heaviest rain falls overnight Saturday night into Sunday morning.  There may be localized flooding (roads and creeks) during that time.  I expect 1.5 to 3″ of rain in the lowlands and 4-6″ in the foothills/mountains.  A few of the usual wet spots will likely see 6-10″!
  3. Large rivers probably won’t flood since the heaviest rain will last less than 24 hours and they are starting at their early Fall low levels.  Ground is also still (somewhat) dry and can absorb the first couple inches of rain.
  4. Strongest wind is Saturday evening and overnight Saturday night
  5. Wind gusts will be STRONGER than what we saw last weekend…60-70 mph on the Coast and 40-50 mph here in the valley.
  6. That is unusually strong for this time of year, especially since leaves are still on the trees to catch the wind; there will definitely be more power outages this weekend.
  7. No snow in Cascades, this is a warm fall system with snow levels up around 8-9,000′.

 

The Details:

Good to see all the models coming into nice agreement on timing and intensity of frontal features this evening.  I’m not too wound up about flooding for the reasons mentioned above and that this isn’t a perfect “atmospheric river” or “pineapple express” event.  Most of those go on for 2 days or so.  The real heavy rain really appears to be later Saturday through very early Sunday.  Check out our RPM for 1am Sunday.  The peak of the rain and wind action appears to be around midnight Saturday night on most models:

Cloud_Rain_1amSunday

What an intense line of rainfall with the front!  This will move down into the Albany-Roseburg area Sunday morning.    Now here is the wind gust forecast:

RPM_Wind9pm

Also surprisingly strong.  If it was December I’d think it was a very impressive wind field.  But it’s only September 28th.  Wow.  Note the 60+ mph gusts just ahead of frontal passage Saturday evening.  The strong wind will back off dramatically after the front moves to the south later in the night.  So if you want to see strong wind at the Coast…try 5pm-Midnight.  Here in the valley, we had some gusts in the 35-40 mph range with the system early this week with just a 7 millibar OLM-EUG gradient.  This time it looks more like 11 millibars.  With such a warm air mass it’s easier for the stronger wind to mix down this time of year, thus 40+ mph gusts are likely Saturday evening/night.  Get your generators ready if you live in an outlying area and have another 10 episodes of The Walking Dead to get through over the weekend (me).

After adding more rain during the day Sunday (not as intense), this is what our RPM shows for accumulation.  It includes Friday’s rain too…a 72 hour total:

RPM_12KM_Precip_NWOR

Note the 10″ spots showing up in the Cascades…the WRF-GFS shows the same thing.  I think 3″ might be a little high here in the valleys, maybe 2″ or so.  So far we’ve seen 2.24″ rain in Portland this month…if we add another 2″, that’ll put us up to 4.24″.  The all-time September record is 4.30″ in Portland.  Even at the wetter downtown location, where records go back to into the 1800s, we’ve never seen 6″.  But let’s not count the “rain eggs” before they hatch.  It will definitely be the wettest September in years here.  Look at the last 10 years:

MarkRain_September

It’s make up time!  The title refers to when I used the graphic LAST September.

 

What happens after Sunday morning?  An interesting wrinkle provided by both the 12z ECMWF and now the 00z GFS.  They both are strongly hinting that another low pressure area develops and moves somewhere into Cascadia (BC to S. Oregon) later Sunday or Sunday night.  The 12z ECMWF looks like this with a 988 low moving into the Olympic Mtns:

ecmwf_apcp_f90_nw

The 00z GFS goes nuts with a 985mb low moving right onto the Long Beach Peninsula!

slp.72.0000

That could be a big windstorm for September 29th; one should assume that solution will change though.  More fun ahead…

Chief Meteorologist Mark Nelsen

 

 

100 Responses to Stormy Weekend Ahead; 3 Storms

  1. Marcustheweathernut says:

    Wow walked outside very blustery and warm crazy!!

  2. MasterNate says:

    Laying my money down on a BUST!!! Maybe a couple of inches of rain through this weekend and no wind gusts higher than 45 mph in the north valley. Just a typical fall storm. But the first in a long time, so it will still be fun.

    • Rob - Southeast Portland says:

      Well, you can’t call it a bust when only 40-45(maybe 50mph) is forecast. No Wind Storm is forecast as of yet. I get what you’re saying though.

    • Rob - Southeast Portland says:

      I have a hunch mixing may lead to some surprises.

    • MasterNate says:

      Hey, I’m always wanting more but this is usually how it goes down. The possibility is there and we get all exited only to be let down at the last model run. I would rather be surprised at the last minute than to have my expectations crushed by normal weather, again.

    • Rob - Southeast Portland says:

      It’s just amazing we’re even discussing any kind of weather event for the end of September. I cannot recall ever in my life seeing a system like this before October has arrived.

    • Ryan says:

      I remember about 10 years ago, this weekend had highs in the mid 90’s! Last weekend of September in 2003. Crazy!

  3. Jesse-Stevenson says:

    I think it’s time for Mark to cool down that 7-day a little. Looks like highs in the 50s to low 60s through next Wednesday. He already busted seven degrees too high on today’s forecast of 63.

  4. Tina * Ridgefield * says:

    Quick question for Rob or W7. Can you tell me if this is a bust where I am or should I get candles and flashlights ready?

    Thank you in advance!

    • WX NINJA says:

      Technically you should never use candles when the power goes out due to the possibility of a gas leak but I tend to forget that when the power goes out sometimes as well. The chances for power outages this go around will be much greater due to the time of year. Many trees still have their leaves on them thus making them more prone to falling on a power line. The extra leaves not only make them heavier but they “catch” the wind easier. Never hurts to have things in place before hand as even if this storm doesn’t knock out your power, one day this fall and winter a storm may.

    • Tina * Ridgefield * says:

      Thank you WX. I do not have gas so I think we are safe. As for the power; it went out with last little wind we had on Sunday so I guess better safe than sorry. I love this weather, that is why I left Los Angeles and moved here 9 years ago! :). Thanks again.

    • Rob - Southeast Portland says:

      I do. I have more gas than a Citgo Truck. Darn chicken nuggets n rice. BUT yes, no candles. What he said.

    • Tina * Ridgefield * says:

      Lol Rob, thanks and nice to have you back. 🙂

  5. runrain says:

    Interesting how it just shoves that circulation down by Hawaii out of the way!

  6. Sifton says:

    LOL!! Boy this weather sure is awesome!!

  7. Lurkyloo says:

    Wowww. My son heads to Outdoor School this weekend. It figures that it looks to POUR rain. Oh well …

  8. Rob - Southeast Portland says:

    18z GFS develops the wave of low pressure both too far offshore, and too far north in latitude(probably 46-47 N)

    980mb heading for central Vancouver Island

    Peaks around 976mb swinging north towards norther Vancouver Island.

    Won’t be a big windstorm for anyone but the Coast with that track. A Wind Event maybe for Willamette Valley G40-50mph.

    ….And now we await the more critical 00z runs tonight. Probably a safe bet though that the model solutions keep this more northerly track.

  9. Timmy_Supercell (Klamath Falls @ 4200') says:

    Think the southern OR cascades could see a lot of this rainfall too? I’ve been longing for a decent soaking for quite some time in Klamath Falls! Just hoping my location doesn’t skip 90% of the action like it typically does…

  10. Kent Estep says:

    I think this weekend alone will be more exciting than all of last winter…

  11. runrain says:

    Excellent graphics, by the way, Mark.

    Yes, the water vapor loop gives the impression that we’ll soon feel like we’re standing underneath Niagara Falls!

  12. pappoose in scappoose says:

    Hahaah!

    “THIS STORM WILL ALSO HAVE TROPICAL MOISTURE WITH IT AND MAY HAVE SOME OF THE REMNANT CIRCULATION OF THE FORMER TYPHOON IN IT.”

    http://forecast.weather.gov/wwamap/wwatxtget.php?cwa=pqr&wwa=special%20weather%20statement

  13. paulbeugene says:

    Looking at the 12Z model output (Euro, GFS, UKMET, Canadian, etc), it appears the most likely scenario is a pretty decent low (for November/December) tracking NE into mid to north Vancouver Island with central pressure in 970-980mb range, with strongest winds limited to OR/WA Coast, NW WA interior. PDX would likely not see gusts above 45mph. Will see if 18Z, 00z model runs agree or change.

    • Rob - Southeast Portland says:

      Probably a safe bet. With this kind of track you don’t want that wave of low pressure developing too soon outside of 130 W, but that is often the case, isn’t it.

  14. WEATHERDAN says:

    AREA FORECAST DISCUSSION
    NATIONAL WEATHER SERVICE PORTLAND OR
    910 AM PDT FRI SEP 27 2013

    .SYNOPSIS…AUTUMN IS WASTING NO TIME GETTING STARTED IN THE PACIFIC
    NORTHWEST. A VERY VERY WET PATTERN IS BEGINNING…WITH THE FIRST
    SYSTEM IN A SERIES SPREADING IN TODAY WITH DECENT RAINS. THE NEXT
    STRONGER AND WETTER FRONT IS FORECAST TO RAMP UP THE RAIN AND COASTAL
    WIND ON SATURDAY CONTINUING INTO SATURDAY NIGHT. THE NEXT EVEN
    POSSIBLY STRONGER SYSTEM IS FORECAST TO BRING MORE HEAVY RAIN AND
    WIND TO THE FORECAST AREA LATER SUNDAY AND SUNDAY NIGHT. LOOK FOR
    RECORD RAINS THIS WEEKEND INTO MONDAY. COOL AND SHOWERY WEATHER
    SHOULD THEN LINGER WELL INTO NEXT WEEK.
    &&

    .SHORT TERM…TODAY THROUGH MONDAY…THE MODELS ARE GETTING MORE
    CONSISTENT WITH THE DETAILS OF OUR HEAVY RAIN EPISODE THROUGH THIS
    WEEKEND INTO EARLY NEXT WEEK. THESE STORMS WILL HAVE TROPICAL
    MOISTURE WITH THEM…SOME FROM FORMER WESTERN TYPHOON PABUK. THESE
    SERIES OF STORMS WILL PRODUCE RECORD RAINFALLS IN OUR AREA…AS WELL
    AS STRONG WINDS AT THE COAST AND LOCALLY INLAND…AND HIGH SEAS NEAR
    THE COAST.

    THE FIRST SYSTEM WAS ALREADY SPREADING ONSHORE THIS MORNING. THE
    RAIN WILL REACH THE PORTLAND AREA LATER THIS MORNING…AND SPREAD
    SOUTH THROUGH THE DAY. THIS SYSTEM HAS 1.5 PWS FEEDING IT…AND
    SHOULD PRODUCE MODERATE RAINS MUCH OF THE AREA INTO THE EVENING.

    THE NEXT STRONGER FRONTAL SYSTEM AS MOISTURE FROM PABUK IN IT. THE
    RAINS WILL INCREASE ON SATURDAY IN THE WARM ADVECTION AHEAD OF THE
    SYSTEM ALONG THE FRONTAL BOUNDARY LEFT OVER FROM THE SYSTEM TODAY.
    HEAVY RAIN WILL INCREASE THROUGH THE DAY ON SATURDAY ACROSS MOST OF
    THE FORECAST AREA. THE GFS AND ECMWF MODELS BOTH SHOW THE ASSOCIATED
    COLD FRONT APPROACHING THE COAST IN THE AFTERNOON…AND MOVING
    ONSHORE SATURDAY NIGHT. THIS WILL BRING MORE HEAVY RAIN…WITH STRONG
    WINDS AT THE COAST AND LOCALLY INLAND. THE RAIN WILL LIKELY BRING
    AREAS OF URBAN AND SMALL STREAM FLOODING. THE WINDS COULD CAUSE TREE
    DAMAGE AND POWER DISRUPTIONS ESPECIALLY AT THE COAST AND OVER THE
    COAST RANGE BUT POSSIBLY IN THE VALLEYS AS WELL.

    IF THE MODELS ARE TO BE BELIEVED…THERE MIGHT BE A BRIEF REPRIEVE OR
    DECREASE IN THE RAIN LATE SATURDAY NIGHT AND EARLY SUNDAY…BUT NOW
    THE MODELS ARE FOCUSING ON ANOTHER STRONG LOW APPROACHING THE COAST
    SUNDAY AFTERNOON AND SWINGING THROUGH SUNDAY NIGHT AND EARLY MONDAY.
    THIS WILL BRING MORE VERY HEAVY RAIN TO OUR AREA…AS WELL AS
    POSSIBLY STRONG WINDS AT THE COAST AS WELL AS INLAND. THE WINDS WITH
    THIS SYSTEM MAY BE STRONGER THAN THE SATURDAY STORM…WITH GUSTS NEAR
    THE COAST UP NEAR 80 MPH POSSIBLE IF THE CURRENT MODELS ARE CORRECT.

    PRECIPITATION AMOUNTS THROUGH MONDAY STILL LOOK TO BE 7 TO 10 INCHES
    IN THE CASCADES AND THE COAST RANGE…WITH 2.5 TO 3.5 INCHES OR MORE
    IN THE VALLEYS. THIS IS A VERY SIGNIFICANT RAIN EVENT FOR OUR AREA…
    VERY UNUSUAL FOR LATE SEPTEMBER AND MORE LIKE A LATE OCTOBER OR
    NOVEMBER OR LATER EVENT. TOLLESON

    .LONG TERM…NO CHANGES. PREVIOUS DISCUSSION FOLLOWS…
    THE EXTENDED MODELS CURRENTLY INDICATE THE HEAVIER RAIN WILL BE
    WINDING DOWN SUN NIGHT. HOWEVER…EXPECT PERIODIC SHOWERS…SOMETIMES
    HEAVY…TO CONTINUE THROUGH THE MIDDLE OF NEXT WEEK AS THE GULF OF
    ALASKA LOW PUSHES TOWARD THE PAC NW. THE TIMING OF THE INDIVIDUAL
    SHORTWAVES THAT WILL DRIVE THE MORE ORGANIZED SHOWERS IS SOMEWHAT
    UNCERTAIN…BUT THE CONFIDENCE IN THE SHOWERY PATTERN IS HIGH. THERE
    IS SOME INDICATION THAT A SHORTWAVE RIDGE WILL PROVIDE A BRIEF BREAK
    FROM THE RAIN SOMETIME DURING THE SECOND HALF OF THE WEEK…BUT THE
    DETAILS AND TIMING OF THIS FEATURE ARE VERY MUCH UP IN THE AIR AT
    THIS POINT. TEMPERATURES ARE EXPECTED TO RUN A GOOD 5 TO 10 DEG BELOW
    NORMAL THROUGH MUCH OF NEXT WEEK. PYLE
    &&
    Latest area forecast discussion from the NWS Portland office.

  15. WEATHERDAN says:

    All that has been missing from the weather this year has been a big snowstorm and a windstorm. We have already had an epic summer here in Salem with lots of very warm days and record warm nights. Four convective (including two major ones) events, and a major inversion induced cold snap in January. Now possibly a major windstorm and even possibly a flood in September. Given that all this happening so far we might even have hope of a big snowstorm happening before the end of December. I can’t ever remember this much being packed into one year. The closest for a year with so many events like this was 1978. There was a large flood in January of 1978. That summer was very warm, with very warm nights for the 1970,s. Then we had a early and very harsh winter. I’m not saying things are repeating themselves only that this is the closest match to what has already occurred. As far as what may be coming up this weekend I am getting quite concerned. Every time a weather update occurs it seems to predict a worsening scenario. Just how bad it gets only time will tell. Oh by the way in 1967 we had a very hot summer followed by a very strong windstorm with gusts to around 80mph in the Willamette valley on October 4th. Nice to see you back Rob. Peace.

  16. archangelmichael2 says:

    For the rain deflect we have had the past 2 years it is now mother nature’s make up time!

    Last fall we were all watching every front literally fall apart.

    • W7ENK says:

      We were? That’s funny… my records indicate a really wet second half of October, and November, and December.

      So does KPDX.

      4.71″ last half of Oct, 1.58″ above average. (Avg is 3.13″)
      8.13″ in November, 2.75″ above average. (Avg is 5.38″)
      7.56″ in December, 2.09″ above average. (Avg is 5.47″)

      20.40″ last fall at PDX, 6.42″ above average. (Avg is 13.98″)

      I guess it must have been a dry rain? o_O

    • archangelmichael2 says:

      Odd. I recall Jan-March being the 5th to 2nd driest on record depending on what weather station you refer too.

      Then March was somewhat wet but April was literally bone dry but luckly no fire danger.

    • archangelmichael2 says:

      And all those rainfall totals you posted were from weak fronts except a brief period in November we saw some moderate systems slide thru.

      Literally there was not ONE single clear night to allow a true winter like feel until the cold inversion in January.

  17. Hal In Aims says:

    Has the dome noticed the approaching rain??

    • W7ENK says:

      I’m sure it has. Been raining downtown since 9:30am. I was hoping to get out of the office at noon today, but that became impossible with the flood of last minute work that keeps sweeping into my office. Looks instead like I may have to stay late again today, and another cold, wet ride home. So much for getting out of town before sunset! Central Oregon may have to wait until next year at this point. Not a happy camper! 😦

    • W7ENK says:

      Oh goodie, and now the wind is picking up in downtown.

      CDS v.2013.1 is upon us!

      Nothing like riding a bike in the rain AND wind! Think we can hold over ’til after dark, too? A trifecta of annoying… how lovely.

      I need a beer.

    • “until next year”? Nope, just wait for the first inversion event in November and make sure you pick a spot that’s above the CB cold pool!

  18. Rob - Southeast Portland says:

    Just put this graphic together.

    I highlighted 3 things that stood out to me on the 12z GFS Extracted Data.
    1) 70+mph winds 2000′ to 2500′ above the surface!
    2) Barometers peaks at 993mb over PDX.
    3) 6hr Pressure rise of 8mb.

  19. Rob - Southeast Portland says:

    12z NCEP/NWS Pacific Surface Analysis

    Deep, cold, 972mb low cross the Aleutians moves southeast into the Gulf of Alaska intensifying a bit further to 969mb. This will be the anchor low west of the Queen Charlotte Islands and exactly how far southeast it moves in proximity to the 50 N line will be critical as the trough it digs to the south will mean everything in terms of where the southern wave development takes place and its track most importantly. That wave of low pressure will swing around the bottom of the trough. This could means things become a bit more favorable for a big wind storm pattern if things come together just right.

  20. Timmy_Supercell (Klamath Falls @ 4200') says:

    Well I certainly do hope for a windstorm! Years since any significant winter weather has occurred other than snow. At least not since 1995… We’re overdue.

  21. W7ENK says:

    All this hype coming from all angles. NWS Curse?

    First bust of the season… I can feel it!

  22. Rob - Southeast Portland says:

    12z WRF
    As I briefly mentioned earlier, a much deeper low develops on the WRF.

    11:00 AM Sunday
    Key differences already seen compared to previous WRF runs or the NAM. Wave develops much sooner probably inside 140 W. It’s what I would call a closed wave transitioning to a surface low about over 130 W. By this point it is deepening rapidly. The fact is does intensify sooner or further offshore near 45-46 N typically lowers the odds for a windstorm for the Willamette Valley due to the re-curving of the storm to the north as it strengthens. With this track more east-northeast we’d really want to see things organize down near 40-42 N or development delayed a bit further inside 130 W.

    2:00 PM Sunday
    Now a strong, compact surface low 981mb(28.97 in) and in response a tight gradient couplet develops.

    5:00 – 8:00 PM Sunday
    Now down to an impressive 976mb(28.82 in) and approaching Vancouver Island. Gradient couplet starting to sweep north-northwest placing the Willamette Valley out of imminent harm of a big wind storm.

    4km Wind Gust Model shows winds peaking Sunday 5:00 PM – 9:00 PM with 30-40kts(40-50mph) gusts fairly common across Willamette Valley(pocket or two of 45kt gusts). The wildcard could be stronger winds mixing towards the surface due to somewhat mild atmosphere, if so, some gusts could maybe reach Warning criteria.

    A Wind Storm probably is likely for the central-northern Oregon Coast, north interior of Washington, and maybe the Puget Sound area. PDX metro probably a Wind Advisory unless the mixing I mentioned is a bigger factor. Gradient peaks somewhere from 5-9 PM with OLM-EUG around 10-12mb and PDX-EUG 5-7mb, not enough to cause alarm. I wouldn’t bite on the WRF solution just yet, awaiting 12z EURO and 00z runs tonight. Cautiously optimistic.

  23. W7ENK says:

    UNUSUAL SEPTEMBER WARNING
    NATIONAL WEATHER SERVICE PORTLAND OR
    1012 AM PDT FRI SEP 27 2013

    http://inws.wrh.noaa.gov/weather/alertinfo/12476575

  24. Marcus the weather nut says:

    Mark… Or anyone what’s the precipitation look like between the hours of 8-11 tonight I have 2 softball games @ delta park just curious if we will be between systems??

  25. Joshua in Lake Oswego says:

    Rob and Paul, you guys are awesome! Thank you for your very well-informed analysis in this blog!

    • Rob - Southeast Portland says:

      No problem. Paul is the man. Mark will have more insight and more model data than I will. He might even post something new soon.

      Posting 12z WRF analysis soon as 4km finishes up.

  26. Rob - Southeast Portland says:

    Good morning,

    12z runs are coming in now….

    12z MM5-NAM handles the wave of low pressure a bit differently.
    2:00 PM Sunday
    994mb(29.35 in) wave of low pressure west of roughly Newport. This is 100-150 miles further south than yesterday’s 00z WRF/12z EURO.

    8:00 PM Sunday
    It then develops a bit slower moving northeast right over PDX which means the tightest gradient couplet would he shifted further south down the valley through Southern Oregon from Eugene southward to Red Bluff, California. This wouldn’t be a wind producer for the northern Willamette Valley or PDX/Metro.

    11:00 PM Sunday – 2:00 AM Monday
    Wave developing further intensifying into a closed, compact low over northeast Washington. It deepens to 985mb(29.09 in) You can see the gradient tightens in response with gusty southwest winds coming in behind the low.


    Again, not a wind storm. Probably very gusty across the Columbia Basin also.

    I do want to point out last runs have shown a strong exit jet of 130-140kts right up along the Coast, so that could fuel stronger development inside 128-129W right to the shoreline. MM5-NAM is a pretty good model, but I tend to favor the WRF a bit more. I’ll post analysis of it when it’s done.

    • Rob - Southeast Portland says:

      TEASER IMAGE.

      12z WRF. UH OH!!! LOW EXPLODES developing rapidly inside 130W 976mb tracking towards southern Vancouver Island.

    • Rob - Southeast Portland says:

      A bit north of where you’d want it for a wind storm, but we need to watch things very carefully now.

    • Rob - Southeast Portland says:

      I wouldn’t bite on the WRF solution just yet, awaiting 12z EURO and 00z runs tonight. Cautiously optimistic.

    • Punxsutawney (aka HIOPHIL) at work by Sunset High elev ~280 says:

      That 976mb low on the WRF could be a big wind producer for the Puget Sound region though. Agreed with your thoughts for us.

  27. Punxsutawney (aka HIOPHIL) at work by Sunset High elev ~280 says:

    Those afternoon showers yesterday dropped .13″ at KHIO and only .02″ at my place a couple miles away. (Thought I wasn’t going to have to worry about biking in the rain for one day!) KHIO will need to record .95″ over the weekend to break the all time September precip record for Hillsboro, currently 3.68″ in 1945.

    Even though I expect a fair amount of rainshadow effect out here with these storms, the GFS is showing 3.44″ through Sunday evening. Even though I’m sure that is overdone by a third at least, I’m still certain the record here is going down big time this weekend.

  28. MasterNate says:

    OH, and BTW, I might as well say it first. Could this be our first BUST of the season? The NWS says, “LATEST DATA INDICATES THE JET STREAM WILL SET UP SLIGHTLY FURTHER
    SOUTH THAN WAS EXPECTED THIS TIME YESTERDAY ” Looks like the southern Valley may see all the action. Just saying.

  29. MasterNate says:

    So is this storm worthy enough for Mark to work this weekend?

  30. Ryan says:

    Mark, what do you see for Eugene from 4-11pm Saturday? Looks like there might be a dry window there? Us Duck fans are curious!

  31. paulbeugene says:

    Not all models showing the low pressure center at hour 66 offshore of NW OR/SW WA. GFS and Euro (Pepsi and Coke of the medium range model world…sorry Pepsi)…both show the storm though. The 6z GFS operational has trended a bit S with the low which would increase the threat to much of Willamette Valley.

    Given that it is early in the fall season and temps will be mild, there won’t be that sludgy layer of cool air at surface to protect us from winds a thousand feet above us.

    A deepening low in low-mid 980s tracking to SW WA would easily deliver gusts 45-55mph in N Willamette Valley. Bigleaf Maples beware.

  32. W7ENK says:

    FWIW, NWS just upped their rainfall estimates for this weekend. Now they’re calling for 3-5 inches PDX metro and valley locations, 6-8 inches Coast, Coast Range, Cascades and Willapa Hills (SW Washington), with some areas in higher terrain seeing “Over 8 inches”.

    Incredible, especially so early in the season!

  33. W7ENK says:

    EARLY SEASON FALL STORM PANIC ADVISORY
    NATIONAL WEATHER SERVICE PORTLAND OR
    515 AM PDT FRI SEP 27 2013

    http://inws.wrh.noaa.gov/weather/alertinfo/12475971

  34. runrain says:

    Mild weather, rapidly deepening lows, highly unusual storms, a Typhoon… I’m sorry. Can’t help thinking back to about this time 51 years ago…

    • Rob - Southeast Portland says:

      Yeah, it does, doesn’t it. But, actually, not one just Typhoon is involved in the whole scheme of things, but two. Appears the long stream of tropical moisture near the date line is remnants from old Typhoon Usagi and the western extent of this Pabuk is being entrained into it. Double whammy of tropical moisture, some energy, and then the strong cold trough over the Aleutians right now. If models showed the 500mb trough digging more sharply offshore that could makes things far more interesting.

    • alohabb says:

      Thanks for coming back and posting Rob! I enjoy the reading and appreciate the time you put in…Keep posting…I got your back!

    • SW says:

      Rob,
      In the past, it seems like when we get these early storms, winter is generally mild. Any thought’s?

      Thank you,
      SW

    • Rob - Southeast Portland says:

      No problem. Besides, Mark chimes in on my group sometimes, so why not return the favor.

  35. Rob - Southeast Portland says:

    00z EURO
    http://www.cascadeaccess.com/~mnelsen/Models/ecmwf500mb_ecmwf.html
    I notice a difference in this run right off the bat. Note on Sunday and Monday how the flow shows a more abrupt turn up from the southwest. Could be an ideal pattern for a fast moving, rapidly developing wave exactly as the 00z WRF shows.

  36. This is the windstorm equivalent of hitting 90 degrees in early October or having a big lowland snow event in mid-March. WAY out of season…

  37. Mike(Orchards 255') says:

    It’s a gonna be windy upstairs!…….Pretty impressive at any time of year…..

    http://www.atmos.washington.edu/~ovens/loops/wxloop.cgi?mm5d2_850t+//72/3

  38. Rob - Southeast Portland says:

    To add further to Mark’s post I see a few other developments worth noting.

    2:00 PM Sunday
    A 990mb open wave of low pressure is seen west of Astoria.

    5:00 PM Sunday
    It then rapidly develops moving northeast into a closed, compact low as it nears the Washington Coast somewhere near Ocean Shores tracking towards Forks at 985mb(29.09 in).

    8:00 PM – 11:00 PM Sunday
    It is still intensifying as it treks northeast across the northern Puget Sound deepening to 982mb, and 980mb(28.94 in) as it moves into British Columbia.

    Why is that important? A fast moving, rapidly developing surface low that is still deepening well after it is inland maintaining its strength and forward motion is a key ingredient for a possible Wind Storm. Plus you have a somewhat mild atmosphere which helps transfer winds mixing them towards the surface more efficiently. Yep, we need to keep an eye on future model runs closely.

  39. nick says:

    If that low verifies on the gfs we would see gust of 70 to 80 mph here in pdx, lets hope not because it will look like a hurricane ripped through town.

  40. BoringOregon says:

    Well we wanted to know what happen with the rain this summer here we go !! is it time to start building a noah’s ark yet !?!?

  41. PhilinForestGrove says:

    Bring it 00z GFS!

  42. Windstorm in September? Now that would be anomalous.

  43. momof2kiddos says:

    Oh geez the beach clean up is on Saturday…I see myself sitting in the car and watching the wind clean the beach.

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