November 30, 2009

A very different pattern: Dry, sun, and fog

We are now about to experience very different weather from the wet, blustery conditions of most of November. The last precipitation for quite a while just passed through tonight..the remnants of a weakening frontal system. High amplitude ridging, associated with building high pressure over the eastern Pacific, will leave us high and dry for the remainder of the work week. The only risk...you guessed it...FOG, particularly tomorrow and Wednesday morning in the lowlands. But we should see plenty of sun later this week, and the mountains will be in sun nearly every day.

Our long range computer models..which have notorious problems with cold wave situations....are not agreeing over the weekend and beyond. Right now the US model..the GFS..shows a major arctic front passage with strong NE winds into Bellingham early Saturday and cold air streaming into our region. (see graphic) But no snow. The European Center Model..normally superior...has a different, warmer, solution. Anyway, I never get excited by snow and cold more than 5 days out...so lets wait until the models are all on the same page. But it is clear we will be dry for days with little or no wind. Normal temperatures. Exceptional weather for raking leaves.

Jim Forman of KING 5 should start preheating his wool hat and gloves, and Seattle DOT...well, you know.

Remember last year. We transitioned to cold and snow about a week later.

Special Lecture: I will be giving a noon-time weather lecture ("Is Rainfall Getting More Extreme?") and a book signing at Elliot Bay Books, December 2 at 12 PM. Downtown in Pioneer Square

KIRO TV WEATHER SPECIAL: Wednesday, Dec 2 at 7 PM. For more info check out: http://www.kirotv.com/station/21774954/detail.html

November 29, 2009

An Amazing Lightning Story


The lightning stuck the antenna on the upper side of the car

Once in a while, I hear some amazing weather stories. Imagine being hit by lightning while driving. Instant destruction of the car's electronics, with the a window blowing out due the blast? Here is a true story shared by Judy Lew--she described it so well, I thought I would leave her own words, slightly abridged. And some pictures she shared. She sounds like the kind of person you would like to have around in an emergency! This lightning hit occurred on the 520 bridge in Seattle during commute time.

This story illustrates how safe it is to be in a car during an electrical storm, since the current will pass around you.

Her story:

On Friday November 6th 2009, I picked up my two daughters in Redmond around 5:50pm and started heading home (west-bound) on SR-520 back into Seattle at the height of rush hour in very heavy traffic. It was dark and rainy, and I was driving a 2003 VW Passat wagon. My girls and I didn’t get to the 520 bridge over Lake Washington until just after 6:15pm (and that was after merging and maneuvering around many cars just to get into the HOV lane before we got to the bridge).

The girls and I were just chit-chatting in the car when all of the sudden – BOOM! We heard a loud explosion and I saw a flash of red light outside of the corner of my eye and all of the sudden my driver side window dropped down and a rush of cold air and rain came in. I screamed (as did the girls) but I had no idea what had just happened. I then realized that the brakes were no longer working. We were moving but I couldn’t slow or stop the car. I then realized that there was something wrong with the car as I couldn’t go faster either and something smelled funny – like there was something burning.You can see where the current passed through the tire.

A blown out window...with some enhancements
by the Bellevue Fire Dept.

I immediately realized that the explosion I heard was related to what was going on with the car (yes, you would think that was obvious at this point but everything was happening faster than I could process). I then realized I needed to turn off the car and stop it as I was worried it was going to explode (the burning smell freaked me out). I immediately used the emergency break, stopped, and turned off the car. It was only at this moment that I got a chance to turn around and see if the girls were okay. Everything happened so fast. Fortunately they were both fine and surprisingly weren’t screaming though my older one looked kind of wigged out. My youngest was just confused.
I immediately called 911 while anxiously looking over my shoulder as I was worried about cars hitting us. We were stopped in the middle of rush hour traffic in heavy rain on the bridge. (For the record, no passing motorists stopped to assist us. No one!) Basically my worst nightmare on the road. The 911 operator had to ask me twice for my name as I had immediately gone into what happened. She surprisingly asked me to move off the bridge. I told her my car stopped working and I was worried about trying to start it up again for fear it would explode. She told me I had to try as it was dangerous to be stalled on the bridge. I tried again but to no avail. Given this she said she would send help.

It was only after I hung up with the operator did I notice that my front passenger window was completely blown out. It was shattered all over my front seat. I couldn’t believe it. I had no idea what happened. Plus the lights in the car were flashing on and off erratically and the car horn started going off. I called my husband and told him the car was going bonkers. We were both befuddled as we had just taken the car in for a 70,000 mile tune-up earlier that week. And now the car had apparently had a catastrophic failure. What was happening?!

After what seemed like an eternity (though was really around 20 minutes), I finally saw flashing lights behind us. The tow truck arrived and soon after a fire truck. My husband called again at the same time and wondered if it was possible that lightning had struck us. He didn’t know of any other explanation. When I saw my blown out window I had actually wondered if we had been shot somehow. I hadn’t even thought about lightning but it made perfect sense as we had the worst thunderstorms the night before and tonight looked just as bad. I told the firemen this and they thought it was conceivable. They had me try to start the car again and confirmed that there was an electrical malfunction. They ended up severing the car’s battery to turn off the horn (which by this time was constantly blaring). After some more investigation, they told me that it indeed looked like lightning had struck the car and had done so through the antenna.

One of the firefighters was a woman. She and everyone else was very nice and reassuring to my girls. When everything appeared to be safe, she reached in and shook my hand and said that I should buy a lottery ticket the next day. She said the car apparently did what it was supposed to and absorbed the impact of the lightning and that we were very lucky. I couldn’t believe it myself. What are the odds of a moving car being struck by lightning?! I couldn’t find the answer online although NOAA says that the odds of being struck by lightning in general is 1 in 3000. When the firewoman walked away, I only then realized that she was the captain of the fire department (it was emblazoned on the back of her jacket).

So how did we finally get home? After the fire truck left, the WDOT tow truck lifted the car up and pulled us in it across the bridge to the first exit until we got to a flat shoulder on the exit ramp where we could safely wait for another (AAA) tow truck and ride to get us home. I was hoping the ride could be fun for the girls but unfortunately it was quite cold as the rain came blowing in through the front windows. It was 7:30pm and the girls were cold and very ready to go home. Fortunately, they did amazingly well given the circumstances and went to bed that evening very happy like nothing had even happened. We were very lucky…

The next day, the University VW dealership was quite accommodating – where we became minor celebrities (for a couple of days). The service manager and garage foreman but said everyone in the VW and Audi dealership had come by to see the car – no one had ever seen anything like it. We’ve also just confirmed with the insurance company that they are “totaling” the car due to the extensive damage to the various electrical systems….so now we’re in the market for another vehicle.

I would like to thanks Judy Lew for providing this amazing story and pictures.


Special Lecture: I will be giving a noon-time weather lecture ("Is Rainfall Getting More Extreme?") and a book signing at Elliot Bay Books, December 2 at 12 PM. Downtown in Pioneer Square.

November 27, 2009

Sun, Fog, and Rain Takes a Holiday

Yes, it is true. The weather stretching into the middle of next week is going to be very different from the rain and wind of November. We are talking DRY now. But with dry this time of year comes the potential for fog.


Take today. Yesterday's front and moderate rain has pushed through western Washington and sunny skies have spread over the lowlands (see satellite picture), including much of the WA coast. There are some low clouds on the western slopes of the Cascades and the coastal mountains--extending to the mountain crests. Temps will be in the upper 40s. Perfect raking and walking weather.

Tomorrow a weak disturbance will bring increasing clouds and rain for the northwest portion of the state, but the computer models suggest the lowlands will be mainly rainshadowed by the Olympics and coastal mountains. Want dry? Go south!

On Sunday the ridge builds up again and rain will end. In fact, for much of next week a very high amplitude ridge aloft will provide dry conditions. Little wind.

The only problem with all this is that when high pressure and clearing skies are parked over us, with weak low-level winds, there is a real chance for fog this time of the year.

Now, I can be pretty sure about this forecast...using a technology I often don't talk about, but use all the time--ensemble predictions. The National Weather Service runs a forecast ensemble--many forecasts all starting slightly differently. If the atmosphere is sensitive and the forecasts uncertain, the slight changes in the initial state will cause the predictions to vary greatly. If there are all on the same page...we can have more confidence in the predictions. Take a look at the ensemble predictions for Sunday (this is called a spaghetti diagram for obvious reasons). Virtually all the predictions are going for the ridging!
Look at the spaghetti diagram for Tuesday afternoon....amazing agreement that far out. Ridging is in!
And remember, we are now finishing the historically wettest period of the year. We have ascended the meteorological peak...we now move slowly (very slowly at first) towards summer. The worst may well be over...especially considering this is an El Nino year.

November 24, 2009

The Thanksgiving Day Forecast


Thanksgiving is coming and with lots of people on the road starting tomorrow, so the forecast is important. Bottom line: a benign weather situation...but not entirely dry.


A front is now offshore and it will move slowly towards us during the day tomorrow, with rain reaching the western lowlands around dinner time (see graphics above). No big deal for us, but the rain will be heavy tomorrow on the western side of Vancouver Island. So travel should be fine for most of the day with no issues crossing the Cascades.

Thursday looks like a wet day as a warm front moves up the coast (graphics). Thi
s warm front is associated with low moving NEward to our south. It will be quite wet on the SW side of the Olympics and the Skokomish could flood (AGAIN!). The low will bring moderate to strong winds (30-40 mph) along the central Oregon Coast and will open up and weaken as it moves inland late Thursday.Behind the system the temperatures will cool and showers will continue on Friday...but mainly over the mountains. Snow level will come down and the snow level will hit the passes. So be ready for some white stuff if you crossing the mountains on Friday. Good day for shopping on Black Friday.

Right now it looks like we might have a big, big treat next week with a ridge from heaven....but we will wait to talk about that.

Special Lecture: I will be giving a noon-time weather lecture ("Is Rainfall Getting More Extreme?") and a book signing at Elliot Bay Books, December 2 at 12 PM. Downtown in Pioneer Square.


Address:
101 South Main Street
Seattle WA 98104

November 22, 2009

The Wettest, Stormiest Two Weeks of the Year!

During Thanksgiving 1983 this was the only way to cook a turkey in western Washington. This particular turkey looks a tad overdone.

Yes, its right now. On average the last two weeks of November are the wettest, windiest, stormiest time of the year here in the Northwest...by any measure. Take a look at the average daily rainfall (see graphic). There is a rapid ramp up in daily average precipitation in October, with the end of November being ground zero weatherwise. It is almost a tradition here in the NW for power outages during Thanksgiving weekend....sometimes with turkey cooked

on the barbecue. Strangely, December is generally much better...less storms and heavy rains.

Our weather changes around here are really strange...very rapid turn on in fall, followed by a slow improvement starting in early December.

Currently, the central Puget Sound region is roughly 2-3 inches ahead of normal November rainfall. But fortunately, this week the situation is far more benign than last ...with some extended dry periods mixed in. High pressure will maintain a hold through much of the week, with only a few weak weather systems passing through. Thanksgiving travel looks very good.

Special Lecture: I will be giving a noon-time weather lecture ("Is Rainfall Getting More Extreme?") and a book signing at Elliot Bay Books, December 2 at 12 PM. Downtown in Pioneer Square.

Address:
101 South Main Street
Seattle WA 98104

The low is here


10:50 AM update...here is the latest Doppler velocity image. I normally don't show you this. Blue is incoming westerly winds of 36 kts. A convergence zone has formed with heavy rain in the central Sound.



The low pressure system moved in a little south of the last model forecast, but strong winds are now hitting the central and southern WA coast . For example, the above image shows the surge to 45 knots at Tokeland at the north end of Willapa Bay. And Astoria and Westport have done the same.

And here is an official spotter report on the southern coast...85 mph.

0430 AM NON-TSTM WND GST 1 SW OYSTERVILLE 46.54N 124.05W
11/22/2009 M85.00 MPH PACIFIC WA TRAINED SPOTTER

DUAL ANENOMETERS...BOTH READ 84 AND 85 MPH PEAK GUSTS.


You can see the wind transition in the vertical looking at the Westport "atmospheric river" observatory information:You can see the wind switch around 12 UTC (4 AM) to the NW, with winds just above the surface reaching 40-50 kts sustained.


As noted last night, this is NOT a general western WA windstorm. Moderate winds will be limited to the area south of Puget Sound.

The next issue is the Strait of Juan de Fuca. Considering the track of the low the westerly surge will probably be weaker...but it still will happen. But the low has to get past us first. Watch the pressure down the Strait....you want to see the pressure at Quillayute rise significantly against Bellingham. It should all start happening during the next few hours...but again, this won't be one of the major westerly surges that cause major damage. Just a garden variety one. Rain should decrease substantially over the next few hours.

Finally, if anyone is interested KCTS TV is repeating my weather program at 1 PM.

November 21, 2009

Update


The forecasting is changing a bit...and getting more serious. Moderate rain has overspread our area and winds in NW Washington have picked up substantially...take a look at Smith Island...getting near 50 kts. That is serious wind.
But the big issue is the small, but significant, low center out there right now. A critical forecast question is its track across the State. New runs suggest it will move a bit further north...crossing the central WA coast and tracking over the south Sound. With this track there will stronger winds along the central WA coast and SW WA (see graphic)...sustained 40-50 mph, with gusts to 70 mph, in some places. Even more serious is that the westerly surge through the Strait of Juan de Fuca looks stronger than suggested earlier...with powerful winds gusting 60 60-70 mph (see graphic).

I am working on research about these Strait surges and writing a paper about them. A particularly strong one hit in October 2003 and destroyed Ivar's Mukilteo Landing Restaurant (my book has a whole section on this. Ivar's rebuilt the restaurant on a weather theme--I love this place and food is very good. The best thing is the weather instrument panel.....if the winds get above a certain level you are supposed to push this red knob and go back to your table and order dessert. ) Another surge in 1990 half destroyed the WSDOT Ferry Elwha where it was being repaired in Everett Harbor. This surge should occur sometime between 4 AM and 9 AM so be aware about it. Northern Whidbey Island could get hit very hard.

PS: Nights like this illustrate why we need the coastal radar. In the NWS discussion the forecaster admits he doesn't know exactly where the low is or its strength. But it is close enough now that a coastal radar would have provided a definitive answer..right now..when we need it....

NW Washington Gets Hit Again...and an Unusual Low

This is a November that just keeps giving meteorologically. And a low with an unusual track is on the horizon.

Today is somewhat of a break. Some sun, some clouds, a few light showers. Good enough to rake some leaves, as I will do soon.

Tonight it will get much more interesting...and Jim Forman from KING TV should be gassing up his van for a trip back north! (By the way, I have been encouraging KING TV to create a DVD with a collection of his weather segments--it would be a hot seller!) A low goes north of us (AGAIN!) produces conditions that will increase winds AGAIN over NW Washington (check out the latest WRF model forecasts). Winds will also increase along the coast, with both regions seeing sustained 30-40 mph with gusts above 50 mph. And of course rain will return.

But that is not the unusual item. Take a look at the sea level pressure forecast for the same time (graphic above). A moderately intense and small-scale low is approaching the southern portion of Washington and will cross SW Washington south of Seattle. There is an intense pressure gradient behind the low, which could produce strong coastal winds (see graphic below), and as the low moves eastward there may be a good eastward surge of westerly flow into the Strait of Juan de Fuca (see graphic). The central Puget Sound area won't see any real wind from this.

And as the low moves through and cool, westerly flow becomes established there will be a LOT of snow in the Cascades tonight through Sunday--at least a foot will fall. Thanksgiving skiing is in the bag now. If our forecasts are wrong and the low goes north of Seattle, the weather would be very different.

It appears that there will be a major pattern shift next week and our intense weather will be over for a while. We will even have a large scale ridge of high pressure in our neighborhood.

November 19, 2009

Why is Northwest Washington getting hit so hard? +Defending Randy Dorn

Its back..... No, not some ghostly apparition...the winds. Here in Seattle the trees are moving again and once in a while I can hear the roar of an approaching gust. (aside...gusts are associated with the downward movement of high speed air from aloft associated with turbulence in the lower atmosphere).

But what is happening here in Seattle is NOTHING compared to the strong winds hitting NW Washington, from Whidbey Island to Bellingham to the San Juans. The power was taken out over large portions of the San Juan's in last nights blow and another wind event is back tonight. Jim Forman from KING-5 TV appears to be camping out in Mt. Vernon, providing dramatic descriptions of the perils of the winds. Be scared, be very scared. Winds gusted to around 70 mph in exposed locations of the San Juan's last night and the rest of the area was close behind.

The wind observations from Smith Island...right off of Whidbey Is....tells the story. Winds gusting to 50 kts day after day! And the winds are coming back up now as we speak! (although it probably won't be quite as bad as last night). Look at a recent wind plot:Strong southeasterlies hitting the San Juans and N Whidbey, but nearly calm in Sequim and Port Angeles. Why this pattern night after night? Can't it give Jim Foreman a break?

The reason for all this is that we have had a sequence of lows or troughs moving across Northern Vancouver Island. This has done two things--created a strong pressure change along the axis of the Strait of Georgia AND sent strong southerlies against the Olympics. When strong southerlies approach that mountain barrier we get enhance high pressure on the windward (southern) side and a lee trough (low pressure) on the northern side near Sequim and Port Angeles. Between the two is an enhanced pressure difference. The superposition of both influences creates a large pressure difference that really accelerates the air moving in NW Washington.
You can see this effect in the forecast pressure and wind pattern for last night (see graphic)Comments on Randy Dorn's Statement

Today Randy Dorn made a courageous, but absolutely correct, announcement. The state will delay the math graduation requirements and will have a two tiered system--students who don't pass the end of course exams at "proficient" level will be able to graduate at a "basic" level if they take more coursework. The Seattle Times has gone after him...accusing him of "blinking" under pressure. But they are quite wrong.

No one wants a more rapid transition to better math instruction and student skills than I and others at the UW. We see firsthand the impact of poor math skills and preparation. But it is absolutely unfair to threaten and deny graduation to our high school seniors when we have provided them with an inferior math education.

The math standards have just recently been changed..they are improved but really not good enough. Many of our districts are using terrible textbooks--long on talk and short on real math. Seattle has extraordinarily poor "discovery" math books at all three levels, and major districts like Issaquah are determined to use books found to be unsound by state mathematicians. Many teachers, and particularly elementary school teachers, don't have sufficient math backgrounds. Fixing these problems and changing the attitudes in our problematic Ed schools will take time.

But some well-meaning, but confused, individuals, such as the editorial writer of the Seattle Times and some business types, believe that pushing a high-stakes exam will somehow fix all the problems. That is complete nonsense. We have lots of exams at the state universities and colleges...entrance exams that test real math needed for real world problems. And you know something? Many of our entering students..the creme of the crop..are failing (more than 50% in community colleges). We had the WASL for years and math capabilities sunk to amazing lows. Randy Dorn believes we need time to fix a failed system left to him by Terry Bergeson and others and he is right. Are we ready to deny graduation to 20, 30 or 40% of our seniors? I really doubt it. And it is not a good idea.

November 18, 2009

Windy Night


Lots of wind tonight....not a major windstorm...but...take a look at the latest observations (see graphic). Sustained winds of 40-50 mph on the coast, with gusts to 60-70 mph at some locations. Also strong winds over NW Washington, with gusts to 40-55 mph. NW WA has really gotten it the last week--as described in my book, a major causes is the lower pressure in the lee (NE) of the Olympics. Winds hitting 30-40 mph over the lowlands...particularly over water. Should quiet down later tonight.

Very substantial precipitation during the next two days, particularly over the mountains: 2-6 inches probable there. And the Cascades should get a few additional feet. It is looking very good for skiing over Thanksgiving...a great gift to the ski resorts. Turns out this is a wonderful year for ski resorts all over the U.S. One reason...we had one of the coldest Octobers on record across the U.S. (see map). But skiers beware....this is an El Nino year and the El Nino effects don't hit until after the new year--low snowpack is a major feature of El Nino late winters. So get your runs in now!

November 17, 2009

Watch Out Olympics!


Today was a fairly quiet day...the front passed through this morning and with the low going north of us, winds relaxed substantially this morning.

Classic post-frontal showers and sunbreaks (see latest infrared picture)....and using the radar one is able to time outdoors activities, such as biking, to stay dry. Weather radar can change your life!

An enhanced band of convection should arrive later tonight...just in time to dampen the views of the Leonids. I would head to Vantage if I really wanted to see them...or hope for a short break in the shower clouds.

Tomorrow another low will approach (see forecast graphic), but it will head far north of us...thus, no windstorm in the lowlands...with one MAJOR exception. Strong southeasterlies will again develop over NW Washington from Whidbey Island north to Bellingham and east to the San Juans (see graphic of forecast wind speed). There will be several days of moderate to heavy rain on the Olympics and the mountains of SW Washington (see graphic for 24-h precipitation ending 4 am on Thursday). Flooding will probably return to the Skokomish.

By the way, I have noted a few media outlets and environmental groups have suggested that yesterdays heavy rains are some indication of global warming's effects. That is simply not true. I gave a talk on this subject today at the UW. There is NO evidence that we have been getting heavier rains lately in the Northwest. There is no trend over the last half-century. Global warming due to mankind's ejection of greenhouse gases MAY change the amount and intensity of rain later this century, but you can't blame our pineapple expresses on human intervention. Check the chapter in my NW weather book on local climate change to get more information on this subject.

November 16, 2009

Winds Surging on the Coast


Very strong winds have hit the coast as the first trough moves its way northward immediately offshore (see weather map for 7 PM). Extremely strong pressure gradient over the offshore waters.

Winds at Hoquiam gusted to 61 knots (70 mph). And the second low is still out there...and starkly beautiful in the latest infrared satellite picture (see below). The new forecast models suggest that the second low will be too far north to give the Puget Sound lowlands a heavy dose of winds...so it appears the next few hours through 1 AM will be the main event.

Heavy rain continues over the Olympic Peninsula, the Willapa Hills, and parts of the Cascades. The latest values from the UW/SPU Rainwatch system are shown below...remember much of the mountains and SW of the Olympics is blocked (why we need a coastal radar!). Really, a coastal radar would have been a big help for this storm, with all the uncertainties in the complex pattern offshore that the models are getting only partially right!


Monday Update


Lots happening. As the satellite image shows a band of moisture, associated with strong southerly and southwesterly winds and warm temperatures is streaming right into us. Complicating the picture have been a progression of low pressure centers that are riding northeastward on the cold side. One low pressure area moved by this morning, producing strong winds on the coast and the NW interior (50-60 mph gusts). Other areas gusted to 30-35 mph. A weak disturbance will move offshore tonight and a strong one will be here tomorrow morning. So expect the winds to increase later today and tomorrow am at least as high as this morning. But this is not a major windstorm like the one in Dec 2006.

Yesterday there were reasons to suspect that the major windstorm suggested by the American models was not in the cards...the UKMET and ECMWF models...as good as and better than ours--had a weaker solution with the low more to the north. The current solution is somewhere in between. The low center is also divided in two...always bad for a big storm.

Heavy precipitation is falling in the Olympics right now and more is expected today....both there, the Willapa Hills and the N. Cascades.

A few graphics of interest:

Here is the predicted sea level pressure at 7 AM tomorrow morning--strong low over Vancouver Island and intense pressure difference on the N. Washington coast and Strait of Georgia. Windy but not exceptional (30-40 mph gusts ) in Seattle, but NW WA and the coast could see 60-70 mph.


Here are the winds tonight as the first weak disturbance moves by. Very strong winds on the coast.
The 24-h rainfall ending 4 AM tomorrow morning--up to 5-10 inches (red colors) over the Olympics, Willapa Hills, and N Cascades. Seattle will get an inch or two before this is over. So rake up those leaves near drains!

High resolution view of precipitation

A Major Cyclone Will Approach Our Coast But Not a Repeat of November 19

A very strong, rapidly developing, midlatitude cyclone will approach the Northwest coast on Friday and move through on Saturday. Fortunately...