October 15, 2016

Today's Major Storm: A Difficult Forecast

Storm day is here for the Northwest.  A strong midlatitude cyclone is now rapidly developing off the Oregon coast, but the forecast is not an easy one:

  • This storm is relatively small, unlike the huge storm suggested by the models earlier this week.    Thus, a small error in the track, say 25 miles,  can produce a very different wind forecast for locations on the periphery of the storm (like Seattle).  
  • The storm is rapidly intensifying right now, which produces uncertainty on exactly the strength at landfall.

The satellite imagery shows impressive development.  Here is the 8:30AM infrared image.  Nice comma structure and a clearly a single low center with strong sinking behind (denoted by the black notch or slot behind it).


A very wet rain shield leads the low center, as indicated by this morning's radar imagery at the same time.

The storm center nearly went over the NOAA/NWS weather buoy 46002, nearly due west of Coos Bay on the southern Oregon Coast.  The pressure dropped to roughly 983.5 hPa and it is clear that the low passed around 1200 UTC (GMT).  We will use that in a second.  The wind sensor was unfortunately broken on the buoy.


We now have the latest model forecasts.  At the start of the forecast (5 AM, 12 GMT/UTC), it shows a 985 hPa low near 130W off southern Oregon.  From the buoy observations we know that the model is not quite deep enough by a few hPa.


 By 11 AM PDT (18 UTC), the storm has intensified to 972 hPa (13 hPa in 6 hr, which is very rapid), with a huge pressure gradient on the south side.   Very windy along the Oregon coast at that time.


By 2 PM PDT (2100 UTC), the storm deeps to 969 hPa is is right off the Columbia.  Intense winds over the northern Oregon and southern WA coasts.

At 5 PM, the low (967 hPa) is near landfall on the northern WA coast, with very large pressure differences (and powerful winds) along the south/central WA coast.  At this point winds should be accelerating over the Puget Sound interior.

Finally, at 8 PM, the low is over southern Vancouver Island, with a large pressure gradient (and winds) from Seattle northward.  After 9 PM, the low will move out and winds will subside.

I will show you the predicted winds in a second, but the key point is that the large pressure gradients will be over the coast and NW Washington and thus the winds will be more modest south of Seattle over the interior.

And now what you really want to see: the predicted wind gusts.
At 11 AM, some gusts of 50-70 knots along the Oregon coast.

 By 2  PM, the strong winds cover the coastal zone from northern Oregon to central WA.

But now lets zoom in over WA.  At 5 PM (000 UTC), with the low just offshore, crazy winds along the central WA coast (gusts over 70 knots)


8 PM?   Very high winds (60-70 knots) over NW Washington, over the western Strait, and the northern WA coast.  Seattle winds will max out around then to roughly 50 knots (57 mph).   Sustained winds will be much less (perhaps around 30 mph).  Less over Tacoma and Olympia.

 By 11 PM, winds are far less over the entire region.  We are done.

There will be some major wave action with the storm along the coast and localized coastal flooding.   The NOAA/NWS WaveWatch III forecast shows 8-9 meter (about 28 ft) waves on top of an elevated sea surface due to low pressure.


So what the key take aways?  This is going to be bad along the coast and I expect lots of power outages there.  Same for NW Washington, with the San Juans, northern Whidbey, and the Bellingham area to have gusts to 60-70 mph and plenty of power outages.    Much less over the south Sound.

1015 AM Visible Satellite Image of the Storm

Seattle is the difficult forecast...it is at the edge of the stronger winds and a small error in the storm track will make a huge difference.  At this point, gusts to 40-50 mph seem reasonable, roughly 10 mph more than yesterday, with greater winds over the northern side of the side and near the water (where gusts to 50-60 mph could well be observed).  With trees leaves and being early season, power outages over Seattle are expected.

And the most difficult question:  what do we call this storm?  The October Ides Storm?  Sukkot Eve Storm.  Songda Storm.  Someone wanted to call it the Chicken Cacciatore Day Storm (October 15 is Chicken Cacciatore Day).  No.....

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96 comments:

  1. Thanks Cliff. Battening down the hatches here in Bellingham. I was really hoping it would fall apart, but it's not looking like it.

    Just to clarify, the wind strength maps are gusts, not sustained, right? So in the blobs of red, I'm looking at gusts up to 50 knots, sustained winds somewhat less, correct?

    There's a lot of information in the various colors and glyphs, I just want to make sure I'm reading it right.

    Thanks again!

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  2. Thank you for these terrific updates sir!

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  3. Does this storm have a name? What does a storm have to be in order to have a name? (just wondering. I know a name doesn't make a difference, but this storm has intrigued me and I'm trying to learn.)

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  4. Easterly gusts to 36mph on east side of Bell Hill in Sequim so far this morning, along with filtered sunlight and rainbows in the west. Blue Hole is holding up so far, but its early. Rain all around us, with the walls of the hole moving really fast a couple of miles away. Not a drop so far.

    Hope the winds change to westerly before the biggest blow (as predicted). We're tucked just below the summit on the east side. Westerlies blow right over us leaving us in the eddy below the summit. Could handle a hurricane from that direction.

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  5. This storm seems to be as difficult to predict as an earthquake. Thanks for your updates, Cliff.

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  6. Let's call it "stormy mcstorm face 2016" in honor of non-traditional naming approaches.

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  7. Add my thanks to those of others - much appreciated.

    Do you anticipate another update this afternoon?

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  8. The Sukkot Eve Eve storm? (The first night of Sukkot, a minor Jewish holiday is October 16)

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    1. That will piss the Gentiles off...2 storms named after Jewish holidays.

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  9. We were thinking of a few names - our favorite is "SWAN SONGDA STORM" because this is the last we will hear from the typhoon Songda.

    If you must tie the name to a date, we suggest "Mid-October Maelstrom".

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  10. Portland NWS is calling it the Ides of October storm.

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  11. Keep it simple and just call it Mid-October Day Storm

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  12. Never fails, always a big storm prediction for greater seattle area and it always ends up less and less of an impact the closer we get to the storm time. I'm getting a strong 'cry wolf' feeling from all these windstorm predictions over the past few years. Anyone seattle and south misses out on what's originally predicted.

    I understand these predictions are good for the NW interior and the coast, but it sounds like a broken record for each windstorm prediction. Always ending up only an event for NW interior and the coast.

    I'm mainly upset at the constant hype in the media including NWS and NOAA.

    Are these forecast models ever considering the tracks of past recent storms? I often wonder the accuracy of the past few years worth of windstorms. The reason I call it a 'cry wolf' feeling is that it seems we could conclude based on recent history that there's a much higher chance of these storms not producing early predicted wind speeds anywhere seattle and southward.

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    1. I feel the same way. This was going to be a storm that was stronger than the Columbus Day storm, now? a friggin breeze...

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  13. @Redmond mom: Songda swan song storm

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  14. My preference is Saint Victoria Strata's Storm it is her feast day ... 15 October

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  15. I hope we can name this storm "No Show."

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  16. It is called “Post-Tropical Cyclone Songda” by the Ocean Prediction Center.

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  17. Sitting in South Bend right now. Light drizzle, overcast, little or no wind. Kinda' scary knowing that this thing is looming just south of us right now and we're seeing the proverbial "calm before the storm".

    As an aside, getting multiple tornado warnings for the last two days has been one of the most bizarre experiences of my life. I've lived here 47 years and never had a tornado warning ... but the last 48 hours ... they've been constant and very real. The lightening and thunder has been constant and surreal.

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  18. I like Songda Storm. Connect it to the origin. Thanks for the weather forecast updates!

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  19. How about calling it the "October Surprise" in honor of the destructive and turbulent election season, which is intensifying at the moment but will soon blow past, leaving us to pick up the pieces and repair the damage.

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  20. 11:45 am in South Bend. By Cliff's calculations, we're about 2 hours out from the start of the "fun".

    Right now it is overcast and calm with a slight drizzle. The proverbial "calm before the storm".

    The last 48 hours here have been intense. Almost constant tornado warnings (the first I've heard in the 47 years I've lived here) and relentless lightening and thunder. One of the creepiest and most unsettling weather related experiences I've ever had.

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  21. How about we call the storm Teresa? Today is the feast of the Spanish mystic Saint Teresa of Ávila.

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  22. Sitting here in at noon in Bellingham with the NWS point forecasts (2 pages) showing maximum gusts of 40 mph and the wind warning indicating 75 mph. Confusing, poor communication, and dangerous.

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  23. Today is I Love Lucy Day. How about the I Love Lucy Storm? Seems especially appropriate as much of Lucy's humor was overreacting, which appears to be many of the forecasts for this storm. I'd say odds are higher that this storm won't warrant a name at all. We've gone from "nearly as intense as Columbus Day" to "Hanukkah Even Part 2" to "lower winds than expected due to the storm's size". Next phase is "phew...we sure dodged a bullet there". ;)

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  24. I vote for Songda Storm. It is how I will always refer to it, anyway. Thanks.

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  25. If it comes in even a little less than advertised, it won't matter what we call it, no one will remember it.
    If it does turn out to be on the scale of the others, I would vote for a sort of portmanteau of "Songda" and our "day" storms and call it Song-day storm.

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  26. Silly me, I wait and hope for a blustery Songda to be played today!
    VHG in Joyce,WA

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  27. Songda's Song...
    Silly me, I hope to hear it and turn up the volume!

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  28. And the most difficult question: what do we call this storm?

    Well there is an obscure name associated with this day Sweetest Day but i don't believe that can be strongly recommended.

    "It is a day to share romantic deeds or expressions. 11 states and parts of two states observe Sweetest Day: Texas Illinois, Indiana, Kentucky, Michigan, Minnesota, Missouri, North Dakota, Ohio, South Dakota, Wisconsin, West Virginia, Washington"

    Mostly we (the great unwashed) really appreciate your updates, Prof Mass.

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  29. Another thanks from Bellingham. I like Sukkot Storm! Sukkotda?

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  30. We are halfway up Vancouver Island, BC on the inland side at Courtenay. Really appreciate your comments and explanations! Any more info you can shed on our area? We've got lots of rivers/lakes/reservoirs that are close to flooding already . . . Thanks

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  31. Stormtober! (Or in Spanish "Tormentobre!")

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  32. 1:15 in South Bend. Getting a few brief gusts, but nothing substantial yet. No sustained winds at ground level, but the sky is much "higher" now and pace of the clouds moving over us has certainly quickened.

    No rain at all right now.

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  33. I was thinking we might remember it as "Trump's Depression" or "The Bad Hair Day"....

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  34. Regarding the "poisonous tail", I noted that the overnight forecaster discussions at NWS talked about worries about a "bent-back occlusion" Not sure if that's the same thing.

    The comment was that the forecast felt good except if we got a bent-back occlusion, and then it could be much worse than forecasted.

    Mention of that was not in the mid-morning forecaster discussion.

    Can anyone talk to this issue?

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  35. @Joseph Ratliff

    I can understand the complexity of storm forecasts for this area. I was born and raised in Washington State and am use to it by now.

    However, I disagree with the overall playbook for this one. Originally this storm was predicted to pass to the north of us, making it a non-event. The closer we got to today the more the media hyped the 'chance' that it could be a historic storm. And now that the day is here, we are back to original prediction of the storm passing to the north and west making it mostly a non-event for seattle and south (definitely not historic), yet the hype in the media, including NWS and NOAA continues.

    I really do appreciate Cliff Mass' blog though, it's generally factual and uses sources to backup the stuff in the blog.

    I think at this point I am having a really hard time trusting any forecast for stormy weather in the great seattle area.

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  36. My name suggestion: Oktoberfest Storm. Our local brewery in Langley, WA (Double Bluff Brewing) rescheduled its Oktoberfest to next weekend due to this storm.

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  37. Clouds are all coming out of the south, but surface winds, or at least the flag on the Turner Joy, are showing winds from the north. I'm sure that will change. From Bremerton.

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  38. Thanks for the forecast and explanations, Cliff. Now we have an idea how they feel in Florida when they are predicting the path and intensity of a hurricane but can't say exactly where it will hit. The WA coast will feel the storm the most and we will get some strong winds north of the Seattle area. But it brings home the point that we should always be prepared for power outages. BTW I vote for the simpler Songda Storm.

    Bob G

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  39. As usual, the predictions from just a few days out were vastly overblown and more suitable for TV News spectacle. So it's difficult to forecast a single storm, but you and "leading scientists" are absolutely certain of doom 50 years out. Call me skeptical.

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  40. Am I being optimistic, or is this thing tracking further offshore than the models suggested? And if so, is that even a good thing?

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  41. Tax Day Storm (for those of us who are slackers and filed an extension on April 15th)

    Thanks for the postings, Cliff. I'd rather be over-prepared -- some may say disappointed -- than to be caught off guard.

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  42. You can always call it White Cane Day storm...
    https://en.m.wikipedia.org/wiki/White_Cane_Safety_Day

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  43. Winds started here in Yelm. Going pretty good. Stores are FULL and packed. Gonna be a long day

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  44. Gotta love the Internet... people will complain about anything.

    From the first day of this developing storm, Cliff and the other weather guys have talked about uncertainties, how differing storm tracks make a huge difference in local experience, etc. So it's here, it seems to be turning into as strong a storm as they predicted back when it was freaking 3000 miles across the Pacific - and yet some people are talking about "crying wolf" and "false alarms" because their specific locality may not get hit with quite as much wind.

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  45. @Scott K, I disagree that this was an instance of "crying wolf", though without question, mainstream media loves to hype just about anything. Weather events are tricky to pin down because, well, it's nature. Cliff on Tuesday forewarned that, "A true monster storm, potentially as strong as the most powerful storm in NW history (the Columbus Day Storm of 1962) will be approaching our area on Saturday." Clearly that isn't going to be the case, and in fact, while it ain't over 'til the fat lady sings, it would seem for those in the Seattle & south Sound region today's weather isn't even remembered as a "storm". (I'm in Whatcom County, and am anticipating more action up here.) I don't generally think of Cliff''s work as hype, and I don't think he and other respected local meteorologists are guilty of crying wolf on this one. Just working at an imprecise science.

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  46. The predicted 2006 storm was no joke, we live in the Cascade foothills, and it sounded like we were in the middle of a war zone from 1AM - 4AM, when all was said and done we lost 25 trees on our forested property, two of which would have hit the house if the wind had been coming from a slightly different direction. Happy to be forewarned even if it doesn't happen the way it was predicted.

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  47. The center of the low does seem to be tracking further offshore and heading in a more northerly direction to pass over Vancouver Island further to the NW than forecast.

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  48. 3:00pm in South Bend. Light breeze with an occasional gust of maybe 10-15 mph. Nothing sustained or serious.

    Rain has picked up and is intermittently heavy, but very sporadic. Rain falling vertically; none of that sideways stuff that we had earlier in the week.

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  49. 3:00 in BOW. Blowing hard.

    I say the Double Bluff storm. Especially if it does go all wussy on us.

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  50. Thank you for the updates. Here in Aberdeen, the yard is currently being flooded, the lights have flickered, and the ducks are tired of the storm. I hope we prepared adequately and don't end up wading out to rescue chickens from their coop.

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  51. Thanks
    Battening down the hatches in Shelter Bay La Conner WA. We could call it the Stevie's Birthday Storm 2016.

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  52. 3:00 in Bothell and it is calm with no wind. I feel like I fell for the hype of a storm and wish the forecasters would be honest and not feel the need to put out the 'worst case scenario'. I actually bought a generator, only because i could afford one. Been following the weather for 36 years and handle insurance claims that result from these events. Worked the 1993 and 2006 storms which were impressive. To think that this event was likened to the Columbus Day, 1993 or 2006 is seeming rather silly. My bad, that I fell for the fear factor that is today's media M.O. Just be honest and not cover your butt when predicting these events.

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  53. 3:00 in Bothell and it is calm with no wind. I feel like I fell for the hype of a storm and wish the forecasters would be honest and not feel the need to put out the 'worst case scenario'. I actually bought a generator, only because i could afford one. Been following the weather for 36 years and handle insurance claims that result from these events. Worked the 1993 and 2006 storms which were impressive. To think that this event was likened to the Columbus Day, 1993 or 2006 is seeming rather silly. My bad, that I fell for the fear factor that is today's media M.O. Just be honest and not cover your butt when predicting these events.

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  54. Weak forecasting. Why all the fear. Columbus Day storm analogy my ass.

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  55. As for storm names, I do find it amusingly interesting that "Gonads" is an anagram for Songda. And in a very palpable sense this storm has, at least the attention of, everyone by the gonads. Of course Dang So is also an anagram. As always thanks for the informative and detailed information: I never new weather could be so interesting until I moved to Seattle.

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  56. Actually, ScottK, the current track is the more southerly one. The first models showed the possibility it might track much further north and pass over the NW end of Vancouver. Instead it's on track now to move over the the NW tip of the Olympic Peninsula, much like the second model from early on. The big difference, as I understand it, is that the storm center is much smaller and so the extreme winds will still happen, just not be nearly as widespread as was initially thought. There are still plenty of people who are going to have an interesting time tonight!
    We are really lucky we can see these develop practically in real time. And don't forget, part of the problem we face right now is that the trees are still in full leaf and there hasn't been a few small storms to prune weak branches, plus days of heavy rain.

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  57. It looks like it is heading west. Looks like a bust for Puget Sound. Anyone else seeing the same thing?

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  59. Nothing happening in Issaquah. You couldn't fly a kite here. The hype since Wednesday has been ridiculous. I hope all the slackers who were "working" from home yesterday because of the storm are doing ok lol.

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  60. Pretty nice fall day, to be honest. No rain, light breeze. Occasional blue sky poking through the clouds.

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  61. Having grown up in Tornado Alley, where plenty of tornado watches and warnings don't manifest into tornadoes, I find it incredulous that people are disappointed or blame "poor forecasting/media hype" that the forecast didn't pan out.

    Forecasts are all probabilistic and they still provide tremendous value in knowing what could happen.

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    1. Aye. Agreed.

      And the consequences of a tornado with no warning are dire. I'd rather prepare for a storm that misses me than get suprised with 80mph winds. It's not like the storm didn't appear, it just did what storms do and meandered.

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  62. Judging by the rotation at 4:00 pm the center of the low is about 60-70 miles west of Cape Flattery and travelling almost due north. This is quite a bit west of the track forecast that had the center passing directly over Cape Flattery midway between 5 & 8 pm. For what it's worth, unless the low does a sudden swing to the east the winds in the Salish Sea area will likely not be as severe as forecast. Certainly no worse than Friday's event.

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  63. I sure hope it isn't heading west. Rainier has been blowing hard but nothing much else.

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  64. Call it the "St Teresa" storm. St. Teresa of Avila was one of the hardest-a** nuns there ever was, and today is her feast day.

    We are feeling the full effect.

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  65. Michael Kennedy, you do realize that the storm is still a few hours off, right?

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  66. I'm so disappointed. We are going to miss this. Radar shows its almost past us in Rainier.

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  67. I'm here in Nanaimo, central Vancouver Island. This storm was hyped big time. All ferry service to the mainland was preemptively canceled for the afternoon and evening. But . . . so far . . . just a little light rain and breezy. Not too impressive.

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  68. Seaview here, about 5 miles north of Cape D. I monitor local high point stations (Radar, Megler, Discovery Heights) and the Columbia River Entrance Buoy pretty closely during storms. Being close to the southern headlands messes with wind but typical trends are storms arriving from SE then filling to SW as they move north. My barometer dipped to 28.98 briefly. The winds were blustery, barely gusty. Overhead clouds were moving north at speed. A typical winter storm. The Idle of October? Snark aside...Having been through many coastal storms in my 60+ years..forewarned is four-armed. Storms/tsunami readiness has made many of our coastal community residents far more resilient than they were 20 years ago. That is a good thing. Good practice.

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  69. One other thing. The most dangerous aspect of the storm series were the tornado warnings yesterday. One came ashore at Manzinata Oregon and a second was seen off Cape D. We had three separate warnings for Seaview. The western skies were truly ominous.

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  70. I'm out in Friday Harbor for this one and walking a few blocks to dinner very soon. The windstorm is no joke out here-- that rumbling sound I hear is not a train, it's the wind!
    I'm not sure if the commentors above are aware of the dangers of mocking our storm gods-- they still have 5 more hours during which to do damage.
    Wondering how the trees near my house on the mainland are doing...

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  71. Second time Cliff Mass and the forecasters have cried wolf and been completely wrong. Are people going to buy it next time, when it could actually be a real threat?

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  72. I should point out that the storm IS here, for some folks it IS strong, and that this thing would arrive at all was predicted when it was still tropical and off the coast of Japan.

    Japan.

    It's a little off of the hype, but it was hardly a failed forecast overall....though personally I could stand it to fail a bit more as I hear the winds get real over Whidbey Island.

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  73. This comment has been removed by the author.

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  74. One day a real storm is going to hit and people won't be prepared because we got used to exaggerated predictions

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  75. Are you disappointed? I appreciate the warning even if it didn't pan out. Hey, our deck furniture is put away and it's not even Christmas!

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  76. Well with regard to, "What do we call this storm," how about 'sad trombone sound'? ;-)

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  77. i was a bike messenger during the inauguration day windstorm. 4x8 sheets of plywood were flying through belltown like huge, deadly playing cards. they blew from upper, incomplete stories of condos which were under construction. also, hundreds of thousands of people had no power. and it was cold.

    yeah, i would rather be given the chance to prepare for the worst, when the worst has the potential to be that bad. but please...post a meme with toppled lawn furniture. :)

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  78. Never fear, Cliff. There's still a chance for a 2006-Hanukkah-Day-like storm on Christmas Day, this year, 2016.

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    1. Ah the 2006 storm. That had serious power here in Seaview. In some ways, worse than '07.

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  79. You're a celebrity meteorologist. Pick your words very very carefully. As I noted before...the tornado warnings were like "Say what?" That was completely unexpected yet very real for some. The radar showed the convoluted bands of rain/thunderstorms and the strange low cloud formations...ominous. I'll never again look at an approaching remenant typhoon so casually with regards to that phenomena.

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  80. Hi Cliff - have you seen this, published today 17-October?

    http://www.nytimes.com/2016/10/23/magazine/why-isnt-the-us-better-at-predicting-extreme-weather.html

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  81. Will there be an iOS version of the uWx Weather App?

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Please make sure your comments are civil. Name calling and personal attacks are not appropriate.