Gloomy Friday

November 28, 2008

Snapshot Quite a gloomy day today with low clouds and occasional drizzle/sprinkles all day long.  Pretty mild though.  I stood outside with just a fleece jacket at the KMart in Beaverton for 1 hour collecting toys for kids (via FOX-12).  I never got cold, so that's pretty good for the end of November.  I see we are still sitting at 50 degrees at the 9pm hour.  Without much clearing it'll be a mild night too.

Dead weather this weekend with surface high pressure almost directly overhead tomorrow, then shifting to our east for Sunday.  Upper level heights go nuts the next 48 hours…peaking above 580dm on the 500mb chart by Sunday AM.  A very warm atmosphere on the way with 850mb temps peaking around +15 to +16 Sunday PM.  Normally I'd totally ignore this for the last day of November due to inversions, but we just START with an east wind Sunday morning and skies may not clear out until that time.  If we get left with no fog in the morning, some mixing from the east midday, and then plenty of sunshine, we could get surprisingly warm.  So I went down the middle and went with a high of 55.  That's as opposed to an "inversiony" 50 or well-mixed lower 60s.

I have a big beef with the 00z GFS rainfall totals for next week.  Heights are awfully high for rain after Tuesday and each run it seems to gradually be giving us more and more longwave ridging through the end of the week.  That's much more like the 12z ECMWF.  In fact 1/2 of the 12z GFS ensembles showed strong upper-level ridging bouncing back midweek like the ECMWF.   So I've ignored the constant rain that the 00z GFS shows from Monday night through Friday.

As for the graphic, I noticed the record low maximum for today is 27 degrees at PDX.  I remember sledding on Thanksgiving Day back in 1985 (in Chehalis).  Today was the date.  I just looked at the maps from the 2nd half of November that year…brrr!  Ah, the good old days!  Mark Nelsen

Thanksgiving Eve

November 26, 2008

Snapshot Nice looking turkey isn't it?

A brief post this evening since we're in the middle of the 10pm show and I need to be on again in a few minutes.

Models handled the sudden increase in easterly flow today really well.  PDX-DLS gradient peaked out quite close to 10 millibars around 8pm but has weakened to around 8 millibars at this hour.  Clearly some downsloping wind mixed in with the Gorge wind, but it'll become more of a plain old Gorge wind by daybreak.  That makes forecasting low temps very difficult.  Peak gusts have made it to right around 50 mph at the west end of the Gorge and will probably stay below 60 mph the rest of the night.  You folks in Troutdale are sure getting the wind tonight with gusts to 44 mph last hour.  The east wind should be completely gone by early afternoon tomorrow, even in the Gorge.

Another sad looking front moves inland tomorrow…maybe some light rain, maybe not.  Same thing Friday night and Saturday morning.

Long range maps have changed around a few times in the last 24 hours.  The BIG picture shows a long wave ridge anchored quite close to the West Coast through at least the end of next week.  There have been hints of wetter (warm or cool, depending on the model) conditions at the end of next week, but nothing too impressive.

That's about it.  I have tomorrow off, but I'll be back Friday.  Enjoy dinner!  Mark Nelsen

Cold and Wet

November 25, 2008

610day.03  An early post tonight.  We are doing a food drive here at FOX-12 all day/evening long.  I'm headed out the the Fred Meyer at Highway 217 & Canyon Road in Beaverton from 7-11pm.  Any of you are welcome to stop by and say hi (and bring food if you can!).  I'll probably be off/on busy from 8-9pm and 10-11pm during our shows, so if I act rude, scowl, and shove you out of the camera view don't take it personally…the show must go on!  Seriously though, feel free to stop by and chat weather.

Once again I've posted the 6-10 day 500mb heights and deviation from normal.  The big red circles tell the story.  A strong 500mb ridge or at least well above normal heights will continue just to our northwest through the next week and a half.  In fact I noticed the most recent models don't have any chance for decent snow in the mountains until about 10 days from now (NEXT Friday or Saturday!).  Gotta go!  Mark Nelsen

A Slow Monday

November 24, 2008

Weather Get Together 2008 Now that's a rough-looking crowd.  I hope there were no fist-fights on Saturday!  Bobby Corser took this picture of many of you folks getting together for pizza Saturday afternoon.  The turnout was definitely larger than last year's get-together.  If you go back in the archive to the December 31st post last winter, you'll see the picture from that one.

Sorry I couldn't make it…my kids were lost (kind of) in the woods.  A neighbor and I spent 30 minutes wandering around looking for them when they had actually just gone over to a friends house down the road.  Long story, but the point is that I didn't make it to the big event.  For those of you that couldn't make it, you can click on the picture to see the names…that way you can put names with faces as you read the comments.

Not much has changed in the maps since I left Friday.  The general trend is for an upper-level ridge to continue quite close to the western coast of Canada and the USA through at least the middle of NEXT week.  Forget about ski season for now.  That's not going to begin until at least the 6th or 7th of December.  If you look at the very end of the GFS the last few runs, you can find some sort of arctic air over us (12z) or quite close (00z).  Of course you have to go out 2+ weeks to find that!  So for now the slow weather continues.

East wind dies down late tonight and tomorrow, then returns quite strong Wednesday and Thanksgiving Morning behind tomorrow's very weak front.  Another very weak system moves in Thanksgiving Night.  Other than that I don't see any rain until the middle of next week?  Whew…that's some slow weather!  Good time to get some work done around the Weather Center…Mark Nelsen

Rex Block and Pizza

November 21, 2008

610day  Nice cold front moving through the west side of the state (OR or WA, pick yours) right now.  It's not going to stick around long and doesn't have a whole lot of moisture associated with it.  Once again models have done really well on timing and intensity of precipitation.  Now we move on to weak onshore flow and a few mainly mountain showers tomorrow.  Easterly low level flow develops Sunday and Monday for dry weather and more sunshine (away from the usual morning fog locations).  A weak Pacific system shears apart with the remains moving overhead sometime late Monday or Tuesday.  Some models say we'll get some light rain, others are dry.  I lean more towards dry with this sort of a split flow seen in the maps, although I do have one sad looking shower sitting on Tuesday morning's forecast.

Forecast is very messy beyond that…models all show some sort of ridging, Omega Block, or Rex Block developing over the West Coast and Eastern Pacific later next week.  The image I've included clearly shows the 6-10 pattern.  Upper level heights are way above average to our north and northwest, and well below normal over California.  A Rex Block is an upper level high centered over an upper level low…similar to the 12z GFS.  As I mentioned last night though, one thing is certain.  No model shows a rainy weather pattern through the end of this month or even the first few days of December.


Steve Pierce would like to remind everyone of the big event tomorrow:

The 2nd Annual "Weather Get-Together" will be Saturday, November 22nd at 2pm in N.E. Portland at the very same location as last year, Stark Street Pizza Company, 9234 SE Stark St, just west of I-205! Bring yourself, a friend, kids, spouses, etc… to talk weather and eat some pizza. It was a great turnout last year and we hope to see everyone again this year!

Here is a driving map:…SE+Stark+Street

I'm not sure if I'm going to make it…depends on what the family is up to.

Mountain Snow

November 20, 2008

Snapshot A bit of snow in the Cascades…enough to make the top of the newscast in this very slow weather month.  Looks like maybe 1" at Government Camp to 5" up at Timberline and Meadows.  Radar shows things really dying off rain-wise at this hour, so this big "snowstorm" is over.

Pretty quiet tomorrow before a weaker system drags it's sorry end through here tomorrow evening.  Our RPM model shows all of .15" with this system and then nothing on Saturday.  Looks like another dry weekend on the way!

Some serious issues in long range forecasts the last 48 hours, and this evening is the worst of all.  00z GFS has Omega Blocking developing a few days earlier than it showed at 00z last night, soon after Thanksgiving.  The GENERAL idea seems to be some sort of ridging SOMEWHERE within 500 miles of the West Coast.  Placement is everything…some model runs have the ridge right over us, some have it offshore which allows cold air to move south from Western Canada.  Drew and I were discussing one thing that ALL models keep showing;  no significant westerly flow.  No model shows significant rainfall.  Looks like November will probably end up being a drier than normal month here…Mark Nelsen

World Toilet Day

November 19, 2008

Snapshot  Tonight John Rinier (a regular contributor)clued me in to the important fact that somebody is trying to get November 19th declared World Toilet Day.  Seems appropriate for our current and forecast weather pattern.  The information can be found here.

I'll do a short post tonight because I'm a bit behind.  It sure is a mild night.  It's still 53 degrees at PDX…we haven't even made it down to our average high temperature yet!  Easterly gradient continues pretty strong this evening.  It seems to have peaked at 7 millibars PDX-DLS around 1z.  Models handled that really well last night.

We just had our RPM model upgraded here at the station…WSI runs the model and then we get the output every 6 hours.  It now goes out to 72 hours instead of 48, which will be useful for small-scale details with winter weather systems.  I'll work on getting some sort of text output from it that weather nuts can view online.

It's been a warm Fall so far, which clearly means our winter will be:  wait, one isn't related to the other so I don't want to hear someone claiming a warm November leads to a warm winter.  In fact I was on ANOTHER weather forum this afternoon and noticed someone had done a comparison of Seattle's November weather versus the following winter's snow potential.  Warm Novembers didn't dent future winter snow totals in La Nina and La Nada years…like we have now.

Well, it just happened.  The first of the season.  Steve Pierce just pointed out the Omega-Block looking setup around 300 hours of the 00z GFS.  That's the first official "cold air warning, send out the Alert Vipers" email that I've received this Fall.  That cold air is pretty close…could be exciting.  Too bad it's at 300 hours away!  Mark Nelsen

AND, we have an Oregon Chapter AMS meeting tomorrow with our own SP talking about the Vancouver Tornado here is the official notice:


The Oregon Chapter of the AMS will hold its November meeting this Thursday, November 20th.  It will feature speakers Steve Pierce and Dave Elson, who will both share interesting information about this past January’s Vancouver Tornado.


The meeting will be held at the Columbia River Inter-Tribal Fish Commission (CRITFC) office at 729 NE Oregon Street in Portland (near the Lloyd Center), in the Celilo (basement) Room.  Signs will be posted at the front entrance directing you.


Start time is 7:00 p.m., and come with a dessert for others to taste.  The Chapter will provide soda and water.


For parking, finding a spot on a nearby street is the best idea.  There are some parking garages nearby as well.  The surface lot immediately adjacent to the building will not be available.


Here is the formal meeting announcement that contains additional information:


I hope you can make it!


Drew Jackson

Secretary, Oregon Chapter of the AMS