November 2018 Weather in the Pacific Northwest

[Jesse]

Fairly strong cell near I-5 between Salem and Corvallis atm. I’ve heard that area is experiencing the longest active tornado drought in the region. Ugh.

[Jbolin]

Fairly strong cell near I-5 between Salem and Corvallis atm. I’ve heard that area is experiencing the longest active tornado drought in the region.

Indeed 

[Kayla]

Wow that is some incredibly cold air on the 12z ECMWF about to dump into the Central US. Looks like it's trying to creep into the PNW as well at the end of the run.

 

Will be interesting to see what the EPS shows.

[Jesse]

Strong line of storms near Kelso/Longview as well.

[TT-SEA]

ECMWF surface maps for the 12Z run and WB are only updated through 30 hours and not moving forward now.   

[MossMan]

ECMWF surface maps for the 12Z run and WB are only updated through 30 hours and not moving forward now.

The massive cold air to our north froze the run.

[Kayla]

Looks like the EPS mean is a notch further west with the block... Control run looks to be fun one.

[Brian_in_Leavenworth]

Looks like we go back to a wet pattern more quickly on the Euro.

Canadian ensemble mean looks active too, fairly wet and seasonably cool (slightly below normal) in the long run.

[Kayla]

Ridge is a lot more stationary on this run which is great to see. That low is still messing with things though.

[Jesse]

Parts of the Portland metro area could hit 60 today. Might aid with convection, I suppose.

[Omegaraptor]

How much rain did PDX get last night? Wunderground doesn’t seem to have the most accurate readings, as it said 0.03” fell yesterday. Maybe it was just counted in today’s readings. What’s a reliable source?

[TT-SEA]

How much rain did PDX get last night? Wunderground doesn’t seem to have the most accurate readings, as it said 0.03” fell yesterday. Maybe it was just counted in today’s readings. What’s a reliable source?

Total of .62 so far since yesterday.

[TT-SEA]

12Z EPS:

 

5-10 day period...

 

 

10-15 day period...

 

[Esquimalt]

12Z EPS:

 

5-10 day period...

 

 

10-15 day period...

 

Not much improvement there.  

[Jesse]

Not much improvement there.

I don’t think there has been an EPS run where the 10-15 day map wasn’t warm for quite some time.

[MossMan]

12Z EPS:

 

5-10 day period...

 

 

10-15 day period...

 

Should I put the boat back in the water?

[Jbolin]

Should I put the boat back in the water?

Did it snow soon after the last time you did?

 

 

[BLI snowman]

I don’t think there has been an EPS run where the 10-15 day map wasn’t warm for quite some time.

It's also an 850mb anomaly map, which means less and less at this point in the year.

[MR.SNOWMIZER]

Just seen lightening on tiger summit

[TT-SEA]

It's also an 850mb anomaly map, which means less and less at this point in the year.

 

Warm usually means wet actually.  

[Jesse]

It's also an 850mb anomaly map, which means less and less at this point in the year.

No doubt.

[Front Ranger]

Until this changes, major PNW cold is unlikely.

 

[Phil]

Been awhile since we’ve seen a true Alaskan vortex pattern.

 

This is a good reminder. It’s catastrophically terrible, despite the 500mb deception.

 

[Front Ranger]

I don’t think there has been an EPS run where the 10-15 day map wasn’t warm for quite some time.

 

I think Tim has been posting the exact same map over and over for weeks now.

[Brian_in_Leavenworth]

12Z EPS:

 

5-10 day period...

 

 

10-15 day period...

 

Interesting the CPC is still calling for temps slightly below normal, with above normal precipitation for the 8-14 day period.  And in their discussions, they don't seem to talk at all about the 850's.  I have read there are a lot of limitations using the 850's to predict temperature, especially during the cool season, maybe that is why.  And if you look at the raw data for the other models that show surface temperatures, which I wouldn't take that seriously anyway, it actually shows what would be below normal temperatures during the same time period.  That might have something to do with the low resolution.

[TT-SEA]

I think Tim has been posting the exact same map over and over for weeks now.

 

I am just posting what it shows for the 5-10 day and 10-15 day mean... I have been making no comments and posting the same blended periods each time which is what I was instructed to do previously.

 

I can stop posting WB maps if that is better.   

[MossMan]

Until this changes, major PNW cold is unlikely.

 

Screenshot_2.png

It does change on December 4th...for a day or two!

[Brian_in_Leavenworth]

It's also an 850mb anomaly map, which means less and less at this point in the year.

 

This is what I have read, you probably know a bit more, is this what you are thinking?

 

http://www.theweatherprediction.com/habyhints/278/

 

LIMITATIONS

 

Forecasting the surface high using the 850-mb temperature has been a popular forecasting technique. First I will go over the limitations of using this method:

 

1. Method does not work on cloudy days or days with afternoon precipitation

 

2. There is a tendency that temperature will be higher than predicted on days the wind is light and will be lower than predicted on days the wind is strong. This is because the low level wind effects the depth of mixing.

 

3. Method assumes air is mixed only between the surface and 850 mb. If the air mixes to a height significantly above or below 850 mb the technique will not work accurately.

 

4. Method does not account for elevation. High elevation regions have a greater chance of mixing air that is above 850 mb.

 

5. Daylight hours effect accuracy. There is a significant difference in daylight hours between the warm and cool season.

 

6. Method only works in a barotropic atmosphere. Fronts or differential advection will contaminate technique.

 

7. Method does not work well in regions with complex topography or near mesoscale temperature gradients such as coastal areas, very hilly areas, and areas near large lakes.

 

The method works best in locations near sea level, in the warm season, on barotropic days, with flat topography, on moderate windy cloud-free days. If any of these conditions are not met then take that into account on the temperature prediction.

[BLI snowman]

Warm usually means wet actually.  

 

At the surface. If we have clear skies and offshore flow, cold anomalies and/or an inversion are now almost a given as we end November.

[TT-SEA]

It's also an 850mb anomaly map, which means less and less at this point in the year.

 

 

You can tell when lowland snow is unlikely with warm 850mb temps... and when the potential is there with cold 850mb temps.  

[Deweydog]

Maps. Ugh.

[Front Ranger]

I am just posting what it shows for the 5-10 day and 10-15 day mean... I have been making no comments and posting the same blended periods each time which is what I was instructed to do previously.

 

I can stop posting WB maps if that is better.   

 

Joke, dude. 

[TT-SEA]

At the surface. If we have clear skies and offshore flow, cold anomalies and/or an inversion are now almost a given as we end November.

 

 

Obviously.  

[Deweydog]

Heads up, Salmon Creek!

[Timmy Supercell]

I wouldn't be surprised if I manage around a half inch of rain today. It's been raining quite a bit here since 2-3am. 

[Jesse]

[Jesse]

Maybe K12 was right, .61” so far is pretty underwhelming considering the forecasts for this storm. Thought today would have more activity to beef the totals up a bit, but pretty quiet thus far.

[Phil]

God d*mn. Ugliest euro weeklies I’ve ever seen. Not even gonna bother posting it.

 

I think the model might be mishandling upstream wavetrains following the Siberian high descent, but still not a pleasant thing to look at.

[Jesse]

Heads up, Salmon Creek!

That’s the location where I am at!

[Front Ranger]

It does change on December 4th...for a day or two!

 

It will take more than that.