January 2014 pattern discussion

[Ginx snewx]

I was just looking at the stratosphere products and look out! Big warm column over eastern Siberia, extends through the entire depth from 10hPa to the 100hPa levels, indicating a massive block and cross polar flow would evolve from N Asia into N Canada. That's beginning D7+ --> until further notice. That is NOT was warm first 10 days of January by any stretch.

I also believe the NAO is neutralizing, and that could be an early signal for actually going negative. The AO is tanking in all members ... but I am almost thinking it is that insane AA/-EPO strength just encroaching upon and stressing the AO domain.

its coming

[donsutherland1]

One other note:

 

The forecast might well be updated. In any case, such forecasts are challenging, so we'll see how things come out.

[CoastalWx]

I'm pretty sure it will be updated. The nrm tier east of the Rockies is most vulnerable to cold. The west and SE could be mild, especially west.it wasn't based on one CFS run.

[donsutherland1]

I'm pretty sure it will be updated. The nrm tier east of the Rockies is most vulnerable to cold. The west and SE could be mild, especially west.it wasn't based on one CFS run.

I agree. I noted that it appeared to closely resemble the CFSv2. IMO, there was rational basis for such a forecast at the time e.g., the CFSv2 idea. It's still very difficult to verify from that far out.  I also agree at the West's and Southeast's possibly being mild.

[CoastalWx]

I agree. I noted that it appeared to closely resemble the CFSv2. IMO, there was rational basis for such a forecast at the time e.g., the CFSv2 idea. It's still very difficult to verify from that far out. I also agree at the West's and Southeast's possibly being mild.

You can't see it, but the discussion noted the possible colder trends north of 40N. I probably would have been colder myself, but that's just me. For my own reasons I'm just happy to see what looks to be a nice wintry period coming up.

[Ginx snewx]

New CFS is very cold

[donsutherland1]

You can't see it, but the discussion noted the possible colder trends north of 40N. I probably would have been colder myself, but that's just me. For my own reasons I'm just happy to see what looks to be a nice wintry period coming up.

I'm happy about the upcoming wintry period, as well. Hopefully at least one of the possible precipitation threats after the New Year will pan out.

[Whineminster]

How accurate are these long term forecasts, if they say "cold" three weeks from now, does it usually pan out that way?

[donsutherland1]

How accurate are these long term forecasts, if they say "cold" three weeks from now, does it usually pan out that way?

Verification at Weeks 3 and 4 is challenging to say the least. Here's a poster from the ECMWF. Notice how verification scores fall off as one moves out in time (4 maps in brown, red, and pink). Red indicates scores that beat climatology. Pink is about equivalent to climatology.

 

http://www.ecmwf.int/newsevents/meetings/forecast_products_user/Presentations2013/Posters/Vitart.pdf

 

Those who try to make such long range forecasts deserve a lot of credit for taking on an exceptionally difficult task.

[ORH_wxman]

Verification at Weeks 3 and 4 is challenging to say the least. Here's a poster from the ECMWF. Notice how verification scores fall off as one moves out in time (4 maps in brown, red, and pink). Red indicates scores that beat climatology. Pink is about equivalent to climatology.

 

http://www.ecmwf.int/newsevents/meetings/forecast_products_user/Presentations2013/Posters/Vitart.pdf

 

Those who try to make such long range forecasts deserve a lot of credit for taking on an exceptionally difficult task.

 

 

I've preached it many times...but sometimes it falls on deaf on ears (not you Don despite me replying to your post)...a 55% success rate at week 4 and beyond will make you a lot of money and is a rare skill to have.

 

 

That stat alone says it all. I have always been uncomfortable with this pattern of -EPO and +AO because the sample size is small because of doman sharing. But I believe when you remove the co-variance of the EPO and AO, you still get a robust negative anomaly for the northern tier. It's amazing when the stats paint a different picture when you tweak and filter them...which is always why I am skeptical of small sample sizes. On first hack, it doesn't look impressive, but then if you filter the co-variance and then regress it at the 95% level, you get like a 0.45 r value on a fairly small sample which says the EPO dominates....but if you take a mean, the AO dominates....who knew?

[OceanStWx]

I've preached it many times...but sometimes it falls on deaf on ears (not you Don despite me replying to your post)...a 55% success rate at week 4 and beyond will make you a lot of money and is a rare skill to have.

 

 

That stat alone says it all. I have always been uncomfortable with this pattern of -EPO and +AO because the sample size is small because of doman sharing. But I believe when you remove the co-variance of the EPO and AO, you still get a robust negative anomaly for the northern tier. It's amazing when the stats paint a different picture when you tweak and filter them...which is always why I am skeptical of small sample sizes. On first hack, it doesn't look impressive, but then if you filter the co-variance and then regress it at the 95% level, you get like a 0.45 r value on a fairly small sample which says the EPO dominates....but if you take a mean, the AO dominates....who knew?

 

What did they serve you at this GTG? Wilks would be proud of confidence levels and r values at 1:40 AM.

[ORH_wxman]

What did they serve you at this GTG? Wilks would be proud of confidence levels and r values at 1:40 AM.

 

It was a drink called "Laminar Layer"...couldn't get enough of it.

[ORH_wxman]

And make sure you get the wind chill warnings out before Ekster....don't let him get credit for this pattern. Bullish on the cold...if I'm wrong, then the next golf outing for you guys is on me.

[OceanStWx]

And make sure you get the wind chill warnings out before Ekster....don't let him get credit for this pattern. Bullish on the cold...if I'm wrong, then the next golf outing for you guys is on me.

 

Somebody thought it was a good idea to pair us up on evening shifts after the new year into the summer. Some weenie forecasts on the way for NNE.

[ORH_wxman]

Somebody thought it was a good idea to pair us up on evening shifts after the new year into the summer. Some weenie forecasts on the way for NNE.

 

 

Ridge bridge over the Beaufort and Chuchki seas with a robust +NAO....not so warm for NNE. I think the chances for an above average month (January) at GYX is about 1 in 1,000,000. That could get ugly on the evening shift. Ekster was always more conservative on the early shift...but he liked to go balls to wall on late and mid-shift.

[OceanStWx]

Ridge bridge over the Beaufort and Chuchki seas with a robust +NAO....not so warm for NNE. I think the chances for an above average month (January) at GYX is about 1 in 1,000,000. That could get ugly on the evening shift. Ekster was always more conservative on the early shift...but he liked to go balls to wall on late and mid-shift.

 

New Euro is saying happy New Year, with a lobe of the PV sending -35 C towards the picnic tables at 4 kft.

 

In fact heights are so low by 00z on the 2nd that flow over the Whites is creating a downslope warming signal around IZG in the 850 mb temps.

[ORH_wxman]

New Euro is saying happy New Year, with a lobe of the PV sending -35 C towards the picnic tables at 4 kft.

 

 

Maybe a pre-welcome to Jan 1994. Your 8 year-old days back then are gonna be tested...maybe. Sans Pinatubo.

[OceanStWx]

I whipped up a little image to illustrate what I mentioned in the previous post. As that PV lobe brushes New England the NW flow will actively be disrupted by the high terrain. So the Euro actually shows the cold air damming up on the windward side, and downslope warming occurring downstream. The reds in this image are -20s, orange -28, and yellows -30 or cooler. That pockets of "warmer" air near IZG is about -23 C, compared to the -33 C over VT.

 

[CoastalWx]

Man, first night FTL in BOS. Ballz cold.

[CoastalWx]

The overall pattern to start January looks cold. I do think we may see somewhat of a relaxation as the PV adjusts, but then another shot of cold perhaps to end the first week. That relaxation period may also be accompanied with a storm.  I like what I see so far. Looks like we have the chance of some real bitter cold.

[CoastalWx]

EPO going nowhere fast.

 

[weathafella]

It would be nice to get a bit of fresh snow for the incoming cold. It's possible we will but no big signal now. But we've had these clippers sneak up on us.

[CoastalWx]

It would be nice to get a bit of fresh snow for the incoming cold. It's possible we will but no big signal now. But we've had these clippers sneak up on us.

 

Only hope is anafrontal NYE kind of deal I think.

[weathafella]

Only hope is anafrontal NYE kind of deal I think.

This is the year for that. 12/6-7, 12/23, 12/31?

[CoastalWx]

Notice that plot I posted. Those blues are OLR or outgoing longwave radiation. Basically where you have outgoing longwave radiation you have convection in that area. Convection means latent heat release which is the product of MJO forcing. Look where that is..just west of the dateline. Extrapolate that heat release poleward and eastward. Result, -EPO.

[weathafella]

I saw Leon working out in the park this morning. A lot of fun on the way friends.

[toronto blizzard]

Notice that plot I posted. Those blues are OLR or outgoing longwave radiation. Basically where you have outgoing longwave radiation you have convection in that area. Convection means latent heat release which is the product of MJO forcing. Look where that is..just west of the dateline. Extrapolate that heat release poleward and eastward. Result, -EPO.

Would you say that the warm water west of the dateline is is helping this pattern. Also do you see this pattern lasting for awhile?

[CoastalWx]

Would you say that the warm water west of the dateline is is helping this pattern. Also do you see this pattern lasting for awhile?

 

I think it will last awhile. I know long range guys want the idea of breaking down the EPO..but I'm not sure it does it in a hurry. To me, if there were to be a concern, it would be the PV being displaced and moving towards Greenland. If that were to happen, then despite the -EPO or +PNA..you will allow the country to warm up considerably. However, the models have been too biased to lift it on out so I would go with the status quo until evidence becomes overwhelming otherwise.  I don't see this breaking down at least through mid January.

 

Now will it mean epic snow? I don't know...the details like that simply cannot be determined. But, I do know a pattern like this is highly conducive to snow.

 

The warmer waters certainly help. It may not drive the tropical forcing, but it helps.

[CT Rain]

Notice that plot I posted. Those blues are OLR or outgoing longwave radiation. Basically where you have outgoing longwave radiation you have convection in that area. Convection means latent heat release which is the product of MJO forcing. Look where that is..just west of the dateline. Extrapolate that heat release poleward and eastward. Result, -EPO.

 

Negative OLR anomalies are a proxy for convection... less OLR bc of more cloud cover/active convection.

 

Obviously all of that is a good sign getting some good forcing toward the Dateline and helping pump up some ridging poleward. 

 

Great look continues!!!

[CoastalWx]

Negative OLR anomalies are a proxy for convection... less OLR bc of more cloud cover/active convection.

 

Obviously all of that is a good sign getting some good forcing toward the Dateline and helping pump up some ridging poleward. 

 

Great look continues!!!

 

Yeah oops. Negative OLR means colder cloud (higher) tops which obviously means less IR radiated back. Was thinking more of a reflectivity standpoint. Obviously more clouds means less OLR from the surface.