Wednesday, March 30, 2016

Beautiful Week Ahead!

I had meant to get to this earlier, but then a funnel cloud occurred over Mill Creek and I had to write about that. Believe it or not, there are people who prefer stormy days with funnel clouds to beautiful, clear, warm sunny days, and I belong to that unique group. However, I'm a big fan of sun as well. In the words of John Ruskin, "there is no such thing as bad weather, only different kinds of good weather," so let's talk about the good weather ahead.

Well, on second thought, let's just talk about the good weather now. It is calm as can be on Lake Washington as I look outside my window, and the only clouds I see are some harmless cirrus clouds. Mt. St. Helens is always spectacular, but right now it is downright gorgeous. I'd love to hit the slopes of the Cascade volcanoes sometime.

Credit: US Forest Service

Right now, we have a HUGE ridge of high pressure over us. Those of you who read my blog regularly know how much I love the satellite images from the MODIS instruments aboard the AQUA and TERRA polar-orbiting satellites, so I'll post one here showing how clear it is over the West Coast. Even if you have no idea what the last sentence just meant, I'm sure you'll understand the picture.

High pressure over our area as seen from NASA's TERRA Satellite. Credit: NASA

Yeah, it's clear. By the way, that diagonal line you see simply shows the boundary of one passage around the pole of this satellite. The satellites that we usually use for meteorology are called "geostationary" satellites and are very useful because they orbit the Earth at the same velocity that the Earth is rotating, so they always stay above a single point on the equator. This allows them to get continuous shots of nearly every place on the globe. However, in order to be geostationary, they must be about 22,326 miles above sea level. Polar orbiting satellites do not have the advantage of remaining stationary over a single point, but they are only several hundred miles above the planet and can thus get much higher-resolution images.

The weather models show this too - the current UW flagship WRF-GFS model shows a massive ridge of high pressure over the Eastern Pacific.

Valid 05:00 pm PDT, Wed 30 Mar 2016 - 12hr Fcst
Credit: University of Washington Atmospheric Sciences
Also, notice how there are areas of low pressure on either side of the high - this pattern is known as an "omega block" because the flow resembles the Greek Letter omega - and it is a very hard pattern to break.

Idealized Omega Block
Credit: University Corporation for Atmospheric Research

This omega block will live up to its reputation, and won't go anywhere for the remainder of the week. 24 hours from now, the omega block has hardly moved at all.

Valid 05:00 pm PDT, Thu 31 Mar 2016 - 36hr Fcst
Credit: University of Washington Atmospheric Sciences

I don't think we'll be breaking any records, but highs on Thursday and Friday have a good chance of breaking the 70-degree mark for many areas in Western Washington, especially Friday. We "cool down" to the low 60s for the weekend, still well above our average high of 56, and turn rainy by next week. Still, we do not look stormy by any means. Spring arrived a little late this year, but I think it's safe to say that it is finally here.

Get outside, and don't forget to wear sunscreen!


Tuesday, March 29, 2016

Funnel Cloud Over Mill Creek!

Credit: NASA AQUA Satellite, ~2pm on Easter Sunday, March 27, 2016

Yesterday was definitely a crazy day for weather! For much of the day, a pretty strong Puget Sound Convergence Zone set up shop in the Northern and Central Puget Sound regions, waxing and waning in intensity and shifting northward and southward as the day went on. The convergence zone ventured further south than usual, actually making it south of Seattle at times. The above satellite picture not only shows a well-defined convergence zone but also shows clearing to the north and south of the zone due to sinking air on either side of it, and lots of scattered clouds (popcorn) offshore denoting little showers and indicating an unstable atmosphere. An unstable atmosphere means there is a large decrease in temperature with height, and as Mother Nature would have it, Sea-Tac had a high of 55 yesterday while Snoqualmie Pass has picked up 8 inches of snow in the last 24 hours. There's still a ton of snow up there, go and get it before it all melts away by the end of this week (but that's for another blog).

Credit: Travis Miller

In addition to bringing gobs of snow to Stevens and Snoqualmie Passes, yesterday's convergence zone actually brought a funnel cloud to Mill Creek! Interestingly enough, funnel clouds are not all that uncommon with strong convergence zones. However, these are called "cold core" funnel clouds and are due to localized areas of circulation due to wind shear within the convergence zone. They are NOT like the funnel clouds and tornadoes common in the Great Plains, which are formed from supercell thunderstorms and are much larger and stronger. For comparison, take a look at the F5 tornado below from Manitoba. Yup, even Canadians get tornadoes!

Category F5 tornado approaching Elie, Manitoba on June 22, 2007
Retrieved from Wikipedia

Huge difference. Even so, even our little cold-core funnel clouds can become tornadoes, and when they do, they can cause quite a bit of destruction.

Supercells are large, severe thunderstorms with a rotating updraft, or mesocyclone. The mesocyclone forms when wind shear caused by relatively light winds at the surface and strong winds aloft creates a spinning vortex of air, and then strong updrafts tilt this updraft so that it is vertical. Both these pictures were taken from a powerpoint presentation I saved from my atmospheric sciences 452 (advanced synoptic meteorology and forecasting lab) class at the UW, and the credit goes to Nick Bond.

The difference in wind strength in the vertical can be quite high, especially in areas near the surface that are sheltered from the wind. I remember one time in December 2007 (the "Great Coastal Gale," to be exact), when winds around a mile up were an astounding 100 knots, while winds away from the immediate coast weren't even at advisory levels. The coast was a different story, and this was arguably the strongest storm on record for some parts of northwest Oregon and southwest Washington - even surpassing the Columbus Day storm!

While supercells get their rotation from differences in wind strength in the vertical, our tiny cold-core funnel clouds and tornadoes are formed from differences in wind strength in the horizontal. With convergence zones, you have winds coming from the south and winds coming from the north, and this can spin up small, localized vortices that manifest themselves as cold-core funnel clouds. I couldn't find a picture of this online, so I drew one myself. This is a picture of the convergence zone around the time that the funnel cloud was sighted, and the pinwheel represents a vortex formed by wind shear from the converging air streams. In this case, the pinwheel is over Mill Creek, which is where people spotted the funnel cloud.

In case you want to learn more about supercell thunderstorms, I have a much more detailed post here. I must of had a lot of time on my hands when I wrote it!!!

Thanks for reading!!!

Saturday, March 26, 2016

Should Seattle Close Its Parks During Windstorms?

There's nothing a Pacific Northwest meteorologist likes more than a big windstorm. Flooding rains are interesting, but they make for terrible skiing (something many meteorologists like to do!) and are not nearly as vicious and intense as a windstorm. Snowstorms are awesome because they are so rare, and there's nothing more beautiful than Seattle with a fresh coat of snow on it, but they still lack the intense cyclogenesis that weather geeks rave about. I personally prefer snowstorms to windstorms (skiing down a hill is more fun than living without power), but when it comes to weather events that meteorologists go ga-ga over, windstorms generally take the cake.

However, I'm beginning to feel a little apprehensive about wishing for these big windstorms. It seems like every windstorm that hits us results in at least one tragic fatality. Recently, most of these have been due to falling trees, but I recall back during the Hanukkah Eve Storm that the majority of deaths were actually due to carbon monoxide poisoning in the days after the storm, as people left their generators running inside their homes and carbon monoxide built up throughout the house. Regardless, I am no fan of any windstorm when it results in loss of life. Damage is inevitable, but loss of life can usually be avoided.

The windstorm on March 13th killed somebody in Seward Park when they were crushed by a falling Douglas Fir, and this has sparked concerns over whether Seattle should close its parks during these windstorms. One of my friends actually went to Seward Park to go storm chasing, and although he planned to get there well ahead of the storm and set up in an area clear of trees, the storm moved faster than expected and he got there right about the time that this fatality occurred. Many trees were down throughout the park, and based on the damage, he estimated that gusts were reaching 55-60 mph. He recorded a gust to 49 mph, so winds above the surface impacting the trees were likely higher.

Credit: Seattle Times

On Thursday, I read an interesting article in the Seattle Times. The article stated that while many other parks and cities close their parks when severe weather strikes, Seattle does not. Seward Park remained open throughout the storm, while other parks like Olympic National Park closed well before the storm hit and others like Point Defiance Park in Tacoma closed as soon as the winds picked up. This begs the question: does it make sense to close parks in Seattle like Seward Park when the winds get too high? Or is this not necessary, and should we let people decide on their own if they want to go to parks during a storm?

My opinions are mixed. I identify as a liberal who likes small government. I am not a libertarian by any means, but in my opinion, government and public agencies should be as streamlined and efficient as possible while still fulfilling certain basic needs. I don't consider deciding whether to keep parks open or not a basic need. On the other hand, organizations like the Washington State Department of Transportation close roads when they are deemed unsafe (ex: the 520 bridge, which was closed during the height of this storm). The Coast Guard can close certain ports to prevent ships from going out if there are rough ocean conditions. The Forest Service can close certain trails, like they did last summer with the Big Four trail near Mt. Baker due to people illegally venturing into the ice caves there and being killed by collapsing ice. So, why shouldn't Seattle Parks and Recreation close certain parks during severe weather?

Credit: Washington Trails Association

It would be hard to enforce these closures, especially on places like the Burke-Gilman trail, which according to UW professor Cliff Mass is one of the most hazardous places to be in a windstorm. So I don't think that closing the parks is the most efficient way to go about solving this problem.

Cliff Mass actually got to this topic before I did, and he suggested that Seattle develop a "Seattle Environmental Hazard App" that would warn you of any threats of severe weather based on your exact location. I think this would be a good idea, and if it is done I'd definitely check it out.

However, at this point, I think the main thing we should be doing is educating people about what to do during severe weather. People should know not to drive or walk in areas with lots of trees when there is high wind, and they should not be out in small boats. For example, last spring, a group of kayakers were caught unaware by strong westerly winds coming down the Strait of Juan de Fuca, even though models predicted the winds perfectly. And that's another thing - we need to be better at communicating what the weather forecast is to the public (I could write a dozen blogs about this).

The number one weather-related killer in the Pacific Northwest is roadway ice, and it is how I almost died while traveling near Blewett Pass when I was 5 years old. But with our large, shallow-rooted trees and often-saturated soils, falling trees are a real danger to lives and property, and we must be better at limiting the frequency of these tragic deaths, because we have had far too many over the past year.

Rest in peace.

Wednesday, March 23, 2016

Sneezing Up A Storm

Wednesday, March 23, 2016
2:28 pm

Every year, around the first week of March, springtime allergies hit me harder than a bottle of caffeine pills. For the majority of the winter, I'm totally fine, and then suddenly, my eyes are the wettest they've been since stupidly eating some absurdly hot chili pepper in Indonesia. Ten to thirty percent of the world has seasonal allergies, and I am one of those people. In fact, I almost sneezed as I was just typing that sentence. Now, I'll be yearning for a sneeze for the rest of the day.

I'm allergic to cats (though we still had one) and mildly allergic to dogs (though I love my dog and wouldn't give him up for the world), but I'm incredibly allergic to horses. Put me on a horse, and I'll sneeze, cry, and punch my nose like you wouldn't believe. I love riding horses too - I just need to take a ton of allergy medicine well beforehand - it takes weeks for the medicine to fully get into my system and have a noticeable effect on my horse allergies.

Luckily for me, my allergies are just an inconvenience. I do not have life-threatening allergic reactions to peanuts or bee stings. But even though those allergies are much more severe, the basic mechanism behind all allergic reactions is the same. So before we get specifically into hay fever, let's talk about how allergic reactions work.

Allergic reactions occur when the body's immune system identifies a normally harmless substance as a hazard to the body's health. When a person is exposed to an allergen for the very first time, they generally do not experience a severe allergic reaction. However, some individuals develop antibodies to these allergens, and the next time an allergen enters the body, the antibodies produce "histamines," which then act on various areas of the body and create different types of allergic reactions. Some allergies, like hay fever, are relatively harmless in the grand scheme of things, while others, like nut allergies, can cause the body to experience a rapid drop in blood pressure and go into anaphylactic shock. In these cases, a shot of epinephrine (an Epi-Pen) must be administered immediately, as the sufferer could die in as little as 15 minutes after being exposed to the allergen. Allergies are not just found in humans; even man's best friend can go into anaphylactic shock if they are exposed to a particular allergen.

A scanning electron microscope image of pollen grains from sunflower, morning glory, prairie hollyhock, oriental lily, evening primrose, and castor bean. Credit: Dartmouth College

Hay fever is caused by the body's immune response to pollen. The severity of hay fever symptoms varies among different people, but it is extremely rare for a person to go into anaphylactic shock because they have been exposed to pollen. That's a good thing, because pollen is pretty much everywhere!

Pollen itself is a powdery substance composed of individual pollen grains, or microgametophytes. Though we usually don't think of plants as having a certain sex, pollen grains produce sperm cells, and therefore are the "male" part of the plant as a whole. This is why bees are so important... they allow plants to reproduce by depositing the pollen grains on the female receptacles, or megagametophytes. In a flower, the microgametophytes are found on the stamen, while the megagametophytes are found on the stigma. So ladies, next time you get ambushed by hay fever, find one of your guy friends and blame him and all his microgametophyte friends for making you sneeze!

Credit: American Museum of Natural History

In the springtime, trees are the most common source of pollen. Particularly notorious trees in my neck of the woods include Cedar and Maple, especially Maple. In summer, grasses are the most prevalent source of pollen, and by autumn, weeds are the main offenders. Although pollen decreases in the winter, some people are still allergic to mold and dust, and indoor air is generally dirtier than outdoor air. Allergies are generally worst on breezy days when lots of pollen has been knocked off of plants, but if it is too windy, cleaner air from the upper atmosphere will get mixed down and pollen concentrations will decrease. Pollen concentrations are usually lowest if it is raining cats and dogs, as raindrops capture pollen and other aerosols and remove them from the atmosphere.

There are a variety of medications you can use to mitigate hay fever. Many are "antihistamines," which reduce the amount of histamines your body produces so you don't have as much of an allergic reaction. Some, like Benadryl, cause drowsiness, while others, like Claritin, keep you perfectly awake. However, in recent years, prescription nasal sprays such as Flonase have become available over-the-counter, and I've had better success with these. These are steroids instead of antihistamines, and are stronger and longer lasting than most antihistamines. If springtime has got you feeling under the weather, get a nasal spray, and you'll be back to feeling better in no time.

Thanks for reading!

Monday, March 14, 2016

Sunday Windstorm Review

Pi Day 2016
4:55 pm

I apologize for not being in the blogosphere yesterday - I was up at Alpental introducing 5-year-olds to poles. I taught lessons up there this year on the weekends and had a spectacular time, and I'd highly recommend anybody who loves kids and skiing to consider teaching ski lessons up there. The kids are so fun, kind, and carefree, and they don't judge me for being a complete goofball weirdo around them. It seems like we let go of these qualities as we grow older, which is too bad because I think they make us special. I hope the kids learned from me, because I know I learned a lot from them.

Yesterday was stormy throughout Western Washington. There were blizzard conditions at times up on some of the ridgetops at Alpental, and I believe ~250,000 people lost power here in Western Washington. Many of the kids were crying because the fierce winds were very scary! I'd estimate that there were gusts 40-50 mph affecting us at times... it was intense. The NWAC site at Dodge Ridge at Summit West clocked multiple gusts to 68 mph yesterday afternoon, and they are significantly lower in elevation than where we were at Alpental.

Sunday's storm was not very well predicted. Early forecasts showed the potential for a major windstorm across the Puget Sound region, with sustained winds of 30-45 mph and gusts up to 70 mph. Storm warnings (sustained winds of 48-63 knots or 55-73 mph) were issued for Puget Sound, something that happens very rarely. Even late Saturday night/Sunday morning, these storm warnings were still up.

Credit: National Weather Service

However, Saturday night's model runs significantly cut back on the predicted strength of the windstorm, and by early Sunday morning, the National Weather Service had replaced the storm warnings in Puget Sound with lesser gale warnings. However, these models didn't have a good handle on the storm either, and neither did Sunday morning's runs, which were initialized approximately 6 hours before the storm was forecast to make landfall. UW's flagship WRF-GFS model had the low making landfall just to the north of the mouth of the Columbia River around 11 am as a rather elongated 984 mb cyclone.

Valid 11:00 am PDT, Sun 13 Mar 2016 - 6hr Fcst
Credit: University of Washington

Instead, the storm made landfall significantly further north on the northern Olympic Peninsula and deepened to ~978 mb. This caused forecasters to increase the forecast strength of the winds for the coast and North Interior, but tone down their forecasts for the Puget Sound area due to the low traveling further north. Although high wind warnings were still up at this time, some forecasts from various outlets were calling for gusts below 45 mph for most of Puget Sound.

Instead, winds ended up being stronger than forecast, even for the Seattle area. Sea-Tac hit 56, and West Point in Magnolia hit 66! Here are some peak gusts from around the region that I retrieved from the National Weather Service... I bolded gusts from major stations or ones that were particularly high.

 935 PM PDT SUN MAR 13 2016



 LOCATION                       SPEED     TIME/DATE       LAT/LON             

 MARROWSTONE POINT LIGHT      67 MPH    0406 PM 03/13   48.10N/122.69W      
 WHIDBEY ISLAND NAS           66 MPH    0359 PM 03/13   48.35N/122.67W      
 COUPEVILLE                   45 MPH    0410 PM 03/13   48.22N/122.69W      
 PORT TOWNSEND                45 MPH    0333 PM 03/13   48.11N/122.77W      
 2 W OAK HARBOR               44 MPH    0404 PM 03/13   48.29N/122.69W      
 2 W FREELAND                 40 MPH    0340 PM 03/13   48.01N/122.58W      

 1 S EASTGATE                 57 MPH    0246 PM 03/13   47.55N/122.13W      
 1 WNW KIRKLAND               46 MPH    0403 PM 03/13   47.69N/122.22W      
 1 NNW BOTHELL                44 MPH    0403 PM 03/13   47.78N/122.21W      
 KENMORE                      44 MPH    0310 PM 03/13   47.76N/122.25W      
 ISSAQUAH                     40 MPH    0340 PM 03/13   47.53N/122.03W      

 INDIANOLA                    51 MPH    0139 PM 03/13   47.74N/122.51W      
 BREMERTON AIRPORT            40 MPH    0155 PM 03/13   47.50N/122.75W      

 HOQUIAM BOWERMAN AP          63 MPH    0122 PM 03/13   46.97N/123.93W      
 1 WNW ABERDEEN               52 MPH    0146 PM 03/13   46.98N/123.84W      

 LAKE STEVENS                 45 MPH    0333 PM 03/13   48.03N/122.06W      
 2 W SNOQUALMIE               44 MPH    1044 AM 03/13   47.52N/121.88W      
 ENUMCLAW                     41 MPH    0252 PM 03/13   47.21N/122.00W      

 EDIZ HOOK CG                 45 MPH    1255 PM 03/13   48.14N/123.41W      

 PAINE FIELD AP               60 MPH    0316 PM 03/13   47.91N/122.28W      
 ARLINGTON AP                 52 MPH    0355 PM 03/13   48.16N/122.16W      
 HARBOUR POINTE               49 MPH    0300 PM 03/13   47.89N/122.32W      
 ALDERWOOD MANOR              41 MPH    0415 PM 03/13   47.82N/122.28W      

 1 WSW BRINNON                56 MPH    0312 PM 03/13   47.67N/122.93W      
 SHELTON AIRPORT              52 MPH    0305 PM 03/13   47.24N/123.14W      
 4 E PORT LUDLOW              47 MPH    0425 PM 03/13   47.92N/122.58W      

 MINOT PEAK                   43 MPH    1100 AM 03/13   46.89N/123.42W      

 QUILLAYUTE AIRPORT           47 MPH    0355 PM 03/13   47.94N/124.56W      
 LA PUSH NOS TIDE GAUGE       42 MPH    0336 PM 03/13   47.91N/124.64W      

 HUMPTULLIPS                  63 MPH    0308 PM 03/13   47.38N/123.76W      
 JEFFERSON CREEK              42 MPH    0536 PM 03/13   47.55N/123.22W      

 LOPEZ ISLAND                 66 MPH    0351 PM 03/13   48.53N/122.87W      
 4 SSW ROCHE HARBOR           58 MPH    0549 PM 03/13   48.55N/123.16W      
 NW DECATUR IS. BEACH         51 MPH    0403 PM 03/13   48.51N/122.83W      
 FRIDAY HARBOR AIRPORT        51 MPH    0315 PM 03/13   48.52N/123.02W      
 2 SE EASTSOUND               48 MPH    0445 PM 03/13   48.67N/122.87W      
 ORCAS ISLAND AP              45 MPH    0615 PM 03/13   48.71N/122.91W      

 SEATTLE TACOMA  ARPT         56 MPH    0138 PM 03/13   47.44N/122.31W       
 BOEING FIELD/KING COUNTY INT 54 MPH    0130 PM 03/13   47.53N/122.30W      
 POINT ROBINSON               53 MPH    0400 PM 03/13   47.39N/122.37W      
 NORMANDY PARK                52 MPH    0149 PM 03/13   47.44N/122.34W      
 3 NW WHITE CENTER            49 MPH    0213 PM 03/13   47.56N/122.39W      
 UNIV. OF WASHINGTON          49 MPH    0403 PM 03/13   47.65N/122.31W      
 3 SW SEATTLE                 48 MPH    0507 PM 03/13   47.58N/122.40W      
 RENTON MUNICIPAL AIRPORT     48 MPH    0220 PM 03/13   47.49N/122.21W      
 1 NNW FEDERAL WAY            45 MPH    0438 PM 03/13   47.34N/122.35W      
 2 NW WHITE CENTER            44 MPH    0415 PM 03/13   47.55N/122.38W      
 3 NW WHITE CENTER            43 MPH    0320 PM 03/13   47.56N/122.39W      
 4 NW SEATTLE                 43 MPH    0506 PM 03/13   47.67N/122.41W      
 1 SE SEATTLE                 42 MPH    0242 PM 03/13   47.59N/122.32W      
 3 WNW SEATTLE                42 MPH    0455 PM 03/13   47.65N/122.41W      
 1 NE SEATTLE                 42 MPH    0159 PM 03/13   47.62N/122.32W      
 1 NE SEATTLE                 41 MPH    0317 PM 03/13   47.64N/122.33W      
 2 W KIRKLAND                 41 MPH    0330 PM 03/13   47.69N/122.26W      

 OLYMPIA AIRPORT              46 MPH    0239 PM 03/13   46.97N/122.90W      
 YELM                         43 MPH    1250 PM 03/13   46.94N/122.61W      
 1 WNW NISQUALLY              41 MPH    0210 PM 03/13   47.07N/122.72W      
 5 S LACEY                    40 MPH    0202 PM 03/13   46.96N/122.80W      

 JBLM-FT LEWIS                58 MPH    1258 PM 03/13   47.08N/122.58W      
 JBLM-MCCHORD                 55 MPH    0119 PM 03/13   47.13N/122.48W      
 3 NNE FREDERICKSON           46 MPH    0330 PM 03/13   47.13N/122.34W      
 TACOMA NARROWS AIRPORT       44 MPH    0255 PM 03/13   47.27N/122.58W      
 1 NW FIRCREST                43 MPH    0150 PM 03/13   47.25N/122.53W      
 RUSTON                       41 MPH    0225 PM 03/13   47.30N/122.52W      
 2 NW ARTONDALE               40 MPH    0327 PM 03/13   47.34N/122.67W      
 2 SW FEDERAL WAY             40 MPH    0143 PM 03/13   47.29N/122.38W      
 SOUTH HILL                   40 MPH    0302 PM 03/13   47.14N/122.27W      

 DESTRUCTION ISLAND           79 MPH    0300 PM 03/13   47.68N/124.49W      
 1 SW KBLI                    68 MPH    0510 PM 03/13   48.78N/122.56W      
 WESTPORT TIDE GAUGE          68 MPH    0200 PM 03/13   46.90N/124.11W      
 CHERRY POINT                 66 MPH    0436 PM 03/13   48.86N/122.76W      
 WEST POINT                   66 MPH    0400 PM 03/13   47.66N/122.44W      
 SMITH ISLAND                 60 MPH    0300 PM 03/13   48.32N/122.84W      
 POSSESSION SOUND             59 MPH    0413 PM 03/13   48.02N/122.27W      
 CAPE ELIZABETH BUOY          58 MPH    0250 PM 03/13   47.30N/124.70W      
 S. LOPEZ ISLAND              56 MPH    0304 PM 03/13   48.40N/122.90W      
 HOOD CANAL BRIDGE            56 MPH    0420 PM 03/13   47.86N/122.62W      
 PORT TOWNSEND NOS TIDE GAUGE 55 MPH    0336 PM 03/13   48.12N/122.75W      
 RICHMOND BEACH               55 MPH    0405 PM 03/13   47.77N/122.39W      
 BLANCHARD                    54 MPH    0350 PM 03/13   48.59N/122.43W      
 SEATTLE                      52 MPH    0306 PM 03/13   47.60N/122.34W      
 HEIN BANK BUOY               49 MPH    0550 PM 03/13   48.30N/123.20W      
 GOLDEN GARDENS SEATTLE       48 MPH    0305 PM 03/13   47.69N/122.40W      
 HENDERSON BAY                48 MPH    0330 PM 03/13   47.38N/122.63W      
 WINSLOW FERRY DOCK           44 MPH    0310 PM 03/13   47.62N/122.51W      
 POINT WELLS                  43 MPH    0410 PM 03/13   47.80N/122.40W      
 KEYSTONE FERRY DOCK          43 MPH    0415 PM 03/13   48.16N/122.67W      
 PORT OF TACOMA #1            42 MPH    0230 PM 03/13   47.28N/122.42W      
 4 ESE PORT LUDLOW            40 MPH    0327 PM 03/13   47.90N/122.60W      

 KIDNEY CREEK                 41 MPH    0128 PM 03/13   48.92N/121.94W      
 SUMAS-RAWS                   40 MPH    0509 PM 03/13   48.91N/122.22W      

 SNOQUALMIE PASS              68 MPH    0500 PM 03/13   47.42N/121.43W      

 PARADISE                     45 MPH    0400 PM 03/13   46.78N/121.74W      

 SEDRO WOOLLEY-RAWS           47 MPH    0642 PM 03/13   48.52N/122.22W      
 BURLINGTON/MOUNT VERNON      46 MPH    0355 PM 03/13   48.47N/122.42W      

 SANDY PT. SHORES             68 MPH    0354 PM 03/13   48.80N/122.71W      
 BELLINGHAM INTL AP           64 MPH    0510 PM 03/13   48.79N/122.54W      
 LYNDEN                       52 MPH    0535 PM 03/13   48.96N/122.41W      
 3 N FERNDALE                 50 MPH    0532 PM 03/13   48.90N/122.58W      
 LUMMI ISLAND                 47 MPH    0435 PM 03/13   48.73N/122.70W      
 3 W FERNDALE                 47 MPH    0427 PM 03/13   48.85N/122.67W      
 4 SSW LYNDEN                 47 MPH    0505 PM 03/13   48.89N/122.49W      
 BLAINE                       46 MPH    0515 PM 03/13   49.00N/122.74W       
 4 ENE FERNDALE               44 MPH    0534 PM 03/13   48.88N/122.51W      
 3 WSW SUDDEN VALLEY          44 MPH    0415 PM 03/13   48.69N/122.40W      
 BLAINE                       42 MPH    0523 PM 03/13   49.00N/122.75W      
 BELLINGHAM                   41 MPH    0504 PM 03/13   48.74N/122.45W      
 1 WNW LYNDEN                 41 MPH    0505 PM 03/13   48.96N/122.48W

These gusts are strong, but they aren't anything we've ever seen before. Still, it's pretty impressive to have a 66 mph gust at West Point in mid-March! The Seattle NWS office dubbed this storm the "Pre-St. Patty's Day Punch," which is pretty awesome. When it comes to naming notable weather events, alliteration counts.

Retrieved from Cliff Mass Weather Blog

Here's a picture I took from Cliff Mass' blog of max gusts recorded during the windstorm. As you can see, higher winds were located over the coast and North Interior. There are quite a few low gusts (10s and 20s), and these are from stations that are not well-exposed to the wind. Over water, gusts were in the 45-60 mph range across the region, and coastal headlands (like Destruction Island) accelerated these winds. Camp Muir at 10,110 feet on Mt. Rainier was the wind winner with a gust to 95 mph.

The most amazing thing about this storm, however, was simply how it appeared on radar and satellite. This was a compact storm, and had a very distinctive bent-back occlusion (the swirl of clouds that spirals counterclockwise to the center of the low). Take a look!

09:15 am PDT, Sun 13 Mar 2016
Credit: University of Washington

As this visible satellite image shows, the storm was off the mouth of the Columbia around 9:15 am, and was heading to the NNE. You can see the tight circulation around the low and the intense cold front along the Oregon Coast. Strong winds are occurring along the coast and mountain ridgetops at this time, but winds in the lowlands are relatively low.

I've seen some cool shots from our coastal radar, but this may very well be the coolest one yet. Take a look at the low! It almost looks like a hurricane. You can really see the movement of the storm with the animated gif below. Moreover, you can see how the reflectivity in the vicinity of the radar increases as time (and wind speed) goes on, and this is due to "sea clutter," or the radar beam reflecting off the top of wave crests. More wind, bigger waves, and thus more sea clutter.

Created with NOAA Weather and Climate Toolkit

Here's the view at 12:10 pm. Compare it to the image from the NASA TERRA polar-orbiting satellite below, which was also taken around 12:10 pm.

Image taken ~12:10 pm by NASA's TERRA satellite
Credit: NASA

There were strong winds over 520, and the bridge was closed for a while. I can't remember the last time that happened, but it has been a long time!

Credit: National Weather Service

But, of course, the day finished on a beautiful note. Take a look at this incredible photo out at Alki Point from Tim Durkan. That has to be one of the most brilliant double rainbows I've ever seen.

Credit: Tim Durkan

Thanks for reading! Things look much calmer this week, especially after Wednesday. Inclement weather returns for the weekend, but it won't be anything like what we saw this past week.

Thank you!

Saturday, March 12, 2016

Windstorm on Sunday?

Saturday, March 12, 2016
11:21 pm

Just a really quick post... I got back home really late tonight and have to wake up in six hours to go hit the ski slopes and teach some ski lessons! 

We've got the potential for a strong windstorm on Sunday. There is some uncertainty with the strength and track of this system, and even though those uncertainties are relatively small, a storm even a little bit weaker than forecast and further away from us could leave us with a few broken limbs here in Seattle, while a stronger storm closer to our region could result in widespread power outages.

Credit: National Weather Service

The National Weather Service currently has high wind warnings for Western Washington and Storm Warnings for all waters (excluding the western entrance to the Strait of Juan de Fuca). Any time there are Storm Warnings for Puget Sound, it's time to prepare for a major windstorm. 

The National Weather Service is calling for gusts up to 70 mph throughout much of the region, including the Seattle area. However, tonight's models are more bearish with the low. At this point, I'd expect gusts to top out around 50-55 mph for most folks. However, as previously stated, small changes in the track and strength of the low could result in huge differences in wind speeds.

Credit: National Weather Service

Right now, the low doesn't look all that threatening, but it is developing at a very fast clip right now. Take a look at the water vapor satellite pic below.

Image taken 11 pm 3/12/2016
Credit: National Weather Service

One thing's for sure - the mountains will a LOT of snow. Even the passes will likely get close to a foot of snow from noon Sunday to noon Monday, so bring chains if you are headed into the mountains. You might need them!


Thursday, March 10, 2016

Brief Southeast Sucker Review

Thursday, March 10, 2016
3:00 pm

That "Southeast Sucker" I blogged about last night stormed ashore early this morning, and delivered a sucker punch to a wider area of the region than I initially forecast. The system actually ended up coming a little closer to our region than the models showed, so the I-5 corridor got a good dose of wind as well. Here are some wind gusts from across the region as compiled by the Seattle National Weather Service.

The most impressive winds were at mountain sites. An anemometer at the top of Mission Ridge recorded a gust of 127 mph from the WSW this morning, and as you can see, both Mt. Baker and Crystal Mountain received gusts over 100 mph as well. Coastal headlands were the next windiest place, with Naselle Ridge on the southwestern Washington Coast hitting a staggering 104 mph and nearby Megler hitting 99 mph! Areas in the Northern Interior were quite windy as well, with many areas hitting 60 mph. Even the Central Sound got some action, with gusts approaching 50 at many locations around Seattle. Sea-Tac hit 44.

The map below shows some of the peak gusts recorded over the past 24 hours (from 5 pm Wednesday to now). As you can see, the mouth of the Columbia really got hit hard... Astoria had four separate gusts over 70 mph!

Credit: National Weather Service - Western Region Headquarters

You may have heard that there was a spectacular solar eclipse yesterday (an event worthy of its own blog). Although the eclipse itself did not affect us, it meant that there were abnormally high astronomical tides, since the sun and moon were in perfect alignment. Combine this with low pressure, strong winds, and high waves, and you've got a recipe for coastal flooding. Check out some of the flooding in downtown Vancouver yesterday!

Credit: Kirk Williams

There was plenty of coastal flooding in Washington as well. Check out some pictures of a road in Lummi Island being flooded this morning! Photos retrieved from the Bellingham Fire Department Twitter feed.

There was plenty of damage away from the water though. Take a look at what happened to this poor Home Depot in Bellingham! It's one thing to see trees down, but to see significant structural damage like this is pretty impressive.

Credit: KGMI Radio

With the North Interior and Coast taking the brunt of this storm, this was a classic Southeast Sucker event. It may have gotten breezy in Seattle, but there's no comparison to what we experienced here in the Seattle metropolitan area and what the Home Depot experienced in Bellingham.

It's hard for me to concentrate while writing this right now... I'm listening to the Donald talk about how he is a unifier. This debate is relatively boring compared to debates past.