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Fall 2017 Model Mehham

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1 hour ago, ORH_wxman said:

There's a lot of uncertainty in the blocking...and I say this in a relative sense compared to the normal amount of uncertainty involved in a D8-14 forecast. You have one model suite (the GEFS) that goes gangbusters with the NAO blocking and western ridging...it's a deep winter pattern here for most of the final 10 days of November in that scenario. You have another model suite that only has less robust NAO blocking and a less amped PNA ridge out west....and the blocking doesn't last as long on the EPS. This scenario would be much much more toned down for any winter threats and also likely introduce a period of milder wx near the end of the month as the block breaks down and we get a flatter flow across the CONUS.

 

I would say at 12z, the Canadian ensembles were a blend between the two but skewed more toward the 00z Euro.

The Euro always seems to crush the dreams of anyone who wants a white Christmas. I am going with the GEFS on this one. Euro finds it difficult to predict robust -NAO. After it was saying just a few days there was going to be one. 

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26 minutes ago, dendrite said:

This snow is vaporizing just as fast as March...the subsurface soils are still warm and eat away at the pack from the bottom-up. Ginxy will be curious to know that my 6" soil temp is 42F. It'll be pushing freezing by mid Dec.

That's odd... the 0.8" I got following the Arctic front sat here for 3-4 days and just started really disappearing yesterday afternoon from Friday morning. 

But we were also well below freezing all weekend.

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1 minute ago, powderfreak said:

That's odd... the 0.8" I got following the Arctic front sat here for 3-4 days and just started really disappearing yesterday afternoon from Friday morning. 

Prob helped that it was frigid right behind the front. The airmass behind yesterday's snow isn't like that one. It's like mid to upper 30s.

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2 minutes ago, ORH_wxman said:

Prob helped that it was frigid right behind the front. The airmass behind yesterday's snow isn't like that one. It's like mid to upper 30s.

Yeah definitely, but it wasn't like the ground warmth was doing anything.

Though we were also 24/13 type days.

I would think then it has more to do with the ambient temp than the ground temp.  As soon as we went to 35F yesterday it started melting.

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3 minutes ago, leo2000 said:

The Euro always seems to crush the dreams of anyone who wants a white Christmas. I am going with the GEFS on this one. Euro finds it difficult to predict robust -NAO. After it was saying just a few days there was going to be one. 

 

There is going to be a good -NAO...the question is how long it gets entrenched...the Euro has been more transient with this in recent days....though today it trended longer and more robust, so we'll see if that continues.

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6 minutes ago, ORH_wxman said:

 

There is going to be a good -NAO...the question is how long it gets entrenched...the Euro has been more transient with this in recent days....though today it trended longer and more robust, so we'll see if that continues.

Oh do you have today's Euro EPS showing the more robust -NAO?. Because I recall just yesterday it was showing pacific air taking over. 

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6 minutes ago, leo2000 said:

Oh do you have today's Euro EPS showing the more robust -NAO?. Because I recall just yesterday it was showing pacific air taking over. 

It does show a more robust NAO in the D8-9 time range...it still has pacific air taking over in the 11-15, but a stronger -NAO early on may take longer to break down than models want to, so it's a trend to keep an eye on. I'm still counting on a relaxation though the week after T-day.

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14 minutes ago, powderfreak said:

That's odd... the 0.8" I got following the Arctic front sat here for 3-4 days and just started really disappearing yesterday afternoon from Friday morning. 

But we were also well below freezing all weekend.

They don’t get it 

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4 minutes ago, Damage In Tolland said:

They don’t get it 

I don't want to get in an arguement over snow preservation but there are a lot of factors that go into it.  It was just weird to see a full sunny day on Saturday do absolutely nothing to a coating of white.  Temps were cold but that's where sun angle comes in. Sunny day with a high of 25F in March will still bake away snow.  Sunny day at 25F in November and the snow is laughing at the sun lol.

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Definitely a little better in the NAO region  on the EPS. However, I expect that area to relax anyways. I am more concerned about the Pacific during this relaxation time. And that's what  everyone else should be  concerned about too. 

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7 minutes ago, CoastalWx said:

Definitely a little better in the NAO region  on the EPS. However, I expect that area to relax anyways. I am more concerned about the Pacific during this relaxation time. And that's what  everyone else should be  concerned about too. 

Looks like PAC is trying to begin a reload a bit more than last night's run. You can see the plains heights lower and the heights near and N of AK higher at the end of the run vs the 00z run. It would probably look better if we had a few more frames out to about day 17 or 18.

 

That kind of agrees with yesterdays weeklies where we saw the reload happening in week 3 and then week 4 was looking pretty good. So hopefully we continue to see that progression....that would be good timing as climo would be a lot more favorable by that point.

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2 minutes ago, ORH_wxman said:

Looks like PAC is trying to begin a reload a bit more than last night's run. You can see the plains heights lower and the heights near and N of AK higher at the end of the run vs the 00z run. It would probably look better if we had a few more frames out to about day 17 or 18.

 

That kind of agrees with yesterdays weeklies where we saw the reload happening in week 3 and then week 4 was looking pretty good. So hopefully we continue to see that progression....that would be good timing as climo would be a lot more favorable by that point.

Hoping for this!!

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1 minute ago, ORH_wxman said:

Looks like PAC is trying to reload a bit more than last night's run. You can see the plains heights lower and the heights near and N of AK higher at the end of the run.

 

That kind of agrees with yesterdays weeklies where we saw the reload happening in week 3 and then week 4 was looking pretty good. So hopefully we continue to see that progression....that would be good timing as climo would be a lot more favorable by that point.

 I noticed that too. My guess is we see some sort of a compromise, hopefully more towards the GEFS…but I'm not so sure about that.  When looking at the height changes, they were sort of all over the place…which  leads me to believe there is some changing going on with that model (EPS).  That probably means, members were all over the place. 

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5 minutes ago, CoastalWx said:

 I noticed that too. My guess is we see some sort of a compromise, hopefully more towards the GEFS…but I'm not so sure about that.  When looking at the height changes, they were sort of all over the place…which  leads me to believe there is some changing going on with that model (EPS).  That probably means, members were all over the place. 

I'm hoping the more robust NAO trend on the EPS for day 8-9 is real...because that would prob take an extra day or 3 to break down vs the model's prog and we would "steal" some more cold days (and hopefully an event, even if minor) before we wait for the PAC reload.

 

 

 

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57 minutes ago, Damage In Tolland said:

They don’t get it 

 Certainly an occasion where i agree with you. Powder freak Knows his snow better than anyone. Low sun angle and arctic airmass Laughs at soil temp Fetish

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14 minutes ago, ORH_wxman said:

I'm hoping the more robust NAO trend on the EPS for day 8-9 is real...because that would prob take an extra day or 3 to break down vs the model's prog and we would "steal" some more cold days (and hopefully an event, even if minor) before we wait for the PAC reload.

 

 

 

Hopefully because if the atl block doesn’t hold that looks furnance like D9+ with AK area digging a vortex in.

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3 minutes ago, STILL N OF PIKE said:

 Certainly an occasion where i agree with you. Powder freak Knows his snow better than anyone. Low sun angle and arctic airmass Laughs at soil temp Fetish

Any snowlover knows this. You just shake your head and move on 

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2 minutes ago, RUNNAWAYICEBERG said:

Hopefully because if the atl block doesn’t hold that looks furnance like D9+ with AK area digging a vortex in.

Yeah...and we shouldn't be surprised if we do get a bout of milder wx for a few days or even a week. But this next 10 days I think will end up ensuring that November does not go into the books as a furnace. We will be pretty solidly below normal for the month by the end of T-day weekend with only about 5 days to go in the month.

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4 minutes ago, STILL N OF PIKE said:

 Certainly an occasion where i agree with you. Powder freak Knows his snow better than anyone. Low sun angle and arctic airmass Laughs at soil temp Fetish

 

1 minute ago, Damage In Tolland said:

Any snowlover knows this. You just shake your head and move on 

 

The key phrase is "Arctic airmass"....which I bolded.

 

Surface temps of 19F will offset soil warmth this early. But when you have a day of 35F or 37F like today, that soil warmth is screaming from below without anything on the surface to offset it. That's why dendrite's snow goes poof.

 

And since it is November, you are getting tons of days above freezing...even in a below average airmass like today.

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