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January Forecast Discussion


REDMK6GLI

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Ice box is coming thru the 10th followed by some moderation thru the 14th then finally a thaw from the 15th thru the 21st it appears. Then we settle back into a cold regime with the re-emergence of the epo ridge which reintroduces the cold back into the east.

Anything is on the table for the end of the month into february. Let's get some blocking in place across Canada to go along with our cold air so we can increase our storm chances.

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I think the ECMWF is dead wrong, as the +PNA rebuilds and the MJO weakens, or gets to favorable phases later in the period.  I think the -EPO and PNA keep the northeast seasonable cold during this moderation with snow to mess, or cold rain for the coastline. 1/11-1/22 time period. LI probably sees 35-40 degrees at warmest 1/11-1/22, that's all.  The GFS old has blizzard around 1/17 weekend, so it is not zero chance of snow for mid January.  Mets chime in please.  This will be interesting case if the ECMWF lost it completely.  I do not trust it this year.  The GFS has not been complete crap all the time either.  The cold shot 1/5-1/11 is severe and similar to the 1/2014 stuff.  Will match the 5-11 F lows and the mid to upper teens highs for several days.... That is for sure.

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The models and esp euro have sucked at times lately. The EC has had a slow improvement from a couple of days ago In the 11-15 day. It's important not to dry hump one set of data. There will be a moderation near day 10 give or take but it may improve after.

 

I agree. None of the long range ensembles picked up amount of cold Jan 6-10th. The Euro ensembles, like the GEFS also show a +PNA spike around the 16th. The Euro ensembles like to lower the heights over Alaska too much.

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The Euro ensemble means and weeklies have done well long range. It nailed the switch to the -EPO from the

run at the start of December. But it has been missing the strength of the WAR/SE Ridge and has been playing

catch up the closer in we get. That's not the kind of bias you want for sustained cold especially when

it's going mild after the Arctic shot this week through the end of the run.

It did pretty bad this week going back. GEFS did better, but not by much. Obviously The further north you are the better, but if you take a compromise with guidance (usually the better thing to do) it's not that bad. The EC already improved from two days ago. The EC trended better again in the 11-15 day compared to 12z.

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But the bias was too cold for tomorrow since it missed the strength of the SE/Ridge WAR. The first week of December

will end up above normal and we ran +3 in December. We get a brief Arctic shot late this week but the ridge returns

shortly after.

 

They always had the cutter potential. Whether the ridge was too strong or weak, it was there, so that's all the matters to me. Have cutter, have temps near 60 no matter what the heights are. Monday or monday night into at least this weekend should be well below. Then probably getting milder after for a time. It tries to pop ridging out west, and the ensembles diverge quite a bit so good luck on an ensemble mean trying to figure out what will happen. I'll take my chances with ridging out west up here. It may be good, it may not..but it's serviceable as long as the black hole over AK doesn't show up.

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FWIW, despite the 500 mb pattern depicted on the ECMWF ensembles, the warmest anomalies are located in central Canada while much of the East Coast is still near normal. That's still 10 days away and the 10-day forecasts have not been very impressive lately.

 

Right, we lose the ridge as a more El Nino pattern develops. Heights actually trend lower along the Gulf coast and near FL.

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Well the weeklies haven't been that bad at times. They did pick up on the December warmth. If you understand how to treat them, this has been an ok winter for them. 

 

I also wouldn't ride the GEFS either because they could ease back on the PNA too. With the forcing west of the dateline and into the maritime continent..models probably will struggle with the EPO and PNA.

 

Cohen called for a SSW, but I do not see it. The vortex is not going anywhere and if anything, consolidates again. So IMHO, we won't see much of a -NAO this month. Maybe I'll be wrong.

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Up there you guys always have more leeway than we do down here in NYC and Long Island. But the big story

is that regardless of what the EPO ridge out west does, the SE Ridge/WAR is going to be a player for at least

the majority of this month. The cold coming in later this week may very well stand as the coldest reading for

the whole month in NYC.

If NYC can get into the single digits, I agree. Such cold has not been very common lately, Last winter was an exception with 7 single digit readings. Also, if NYC gets into the single digits, it will be the first case of consecutive winters with single digit readings since 2003-04 and 2004-05.

 

After the moderation, it will be interesting to see what happens. If the EPO ridge rebuilds, as it has done repeatedly since November, and if the PNA is largely positive (likely given the PDO+) and if the AO goes negative for a sustained period (the most speculative aspect right now) late January into early or mid February could be fun. If the AO stays largely positive, then the pattern will be a more challenging one. If the EPO ridge does not rebuild then odds of a warmer outcome would increase markedly. I suspect by mid-January, we'll begin to get some better ideas concerning the likelihood of various scenarios.

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A neg WPO combined with a POS PNA still keeps Canada cold . By day 12 we develop a trough in the SE .

The higher heights are bring pushed north. You still allow troughs to get forced through the lakes.

It's the same look we saw for the 1st 15 days I'm December ( when everyone was yelling torch ) it didn't happen because what s1 SD below normal in Manitoba is colder than normal in NYC .

Take a look at the Euro s 850s day 12 thru 15. It's bringing high pressure and the trough back the lakes.

There's no more ridge so there is no resistance.

Not a cold pattern but not above. And with 38 28 splits at KNYC if you are 1 below like in December at this time. That's not a torch.

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The Euro painted an entire December torch. Day 1 thru 20 were .3 below normal Dec 2 thru the 15 much colder than that ( with almost the same look at 500 mb ) keep in mind the splits are colder a month later.

Yes December was plus 3 but that's a little misleading. That was ALL accomplished the last 10 days of the month with 5 days of plus 15 as we a huge cut off pulled the trough west for a week.

Now I am not saying we don't moderate from the 10 thru 15th it just may not be as warm as it looks at 500mb

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Who cares what the GEFS show long range when their cold bias has been terrible since this winter began.

I guess  you missed that December ran +3 and blew past expectations with the first week of January

running warmer than expected. I can remember you also arguing that some of the fantasy long range

snows showing up over the last month had a chance when the 500 mb pattern said otherwise.

Even if you take a Euro GFS compromise after day 10, the temps will still be a some level

of above normal.

That's how I feel about both models and how any objective forecaster would feel as well. The Euro had us torching all of December and blew it. It was also days late on this cold shot, and when it finally showed it, overdid it. Then you spin these failures into positives and I expect more from you as one of the better posters. The GFS had us getting a sustained -NAO and moving the MJO through phases 7 and 8 for weeks in it's LR forecast and blew it. Forecasting this winter is about much more than cherry-picking which models show your forecast and riding indeces into the ground. It's also about more than SSTs and QBO values and SSWEs. Some combination of these features has determined our weather and no one person or model has it figured out yet.

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I mean think about it. I'd rather my height anomalies in srn Canada then off the SE Coast. Higher anomalies off the SE coast where it is already warm, is the killer. It's not a cold and snowy pattern, but it's a 2011 AK block hole either.

Right..the SE ridge is gone after this week. Kaput. Not sure what folks are talking about having it there all month?

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The whole month on average of December did torch across the US so I am not sure how you keep missing this point

attachicon.gifDec14TDeptUS.png

Yes Dec 1 thru 20 was warm over most of the CONUS but not KNYC . Dec was 1 was 62 45 and still the 1st 20 days were BN.

The reason there was a SE trough that saved us. Now that's not a snowy pattern on the Euro post day 10. It's not a cold pattern day 12 thru 15 but without a SE ridge you will get troughs through the lakes. So that is not a torch.

Check out Dec 2 thru 20. Look at those pos height anomalies west of the MISS and all over Canada they never made it east.

The torch came last 10 days of the month when the SE ridge finally popped and no question we ended up plus 3. But if you are looking at that pattern at 500 it is important you see what that just yielded you the first 20 days a month earlier and keep in mind your splits are now 10 degrees colder.

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The first 20 days were still above normal in NYC averaging +1.2. It really doesn't matter that there were some cold

pockets in there as the warmth came on strong enough to win out. There were some very cold days in January

2013, but the warmth won out. Last January was different as there were enough frigid readings in the single

digits to cancel out the brief thaw's influence in the middle of the month.

The 62 on Dec 1 put a full degree on that 20 day average. As it was I saw KNYC plus .05. LG minus .01. My fight isn't 1 degree . But plus 1 with that same look at 500 w splits of 38 28 means we don't torch .

I know everyone cares about snow. But any shortening of the wave lengths in Jan with normal temps sometimes gets it done albeit not In a big way.

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When doing a monthly, you have to go with the mean since the dailies can be very variable at times.

 

The way I see the day 10 and beyond means is if you go 50% ECMWF 25% GFS 25% GEM we still end up

above normal. I really don't know if the pattern will verify as warm as the Euro ensembles, but the GFS cold bias 

is still there. So a compromise will still tip the scales to above normal with the ridge near the East Coast and

the +AO continuing.

 

I was only using the 1st 20 days in Dec to draw similarities to the maps at 500 . Since those positive height anomalies showed up during the 1st 2 weeks in Dec with the MJO going through 4-5-6 and we still did not torch .

So I am just saying those 500mb forecasts on the Euro does not scare me as we  lose that ridge in the east day 11- 15 on both the Euro and GFS .

 

 

 

Yes the GFS is much colder . 

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There is no source for fresh cold air after day 10 as a big chunk of the -EPO ridge splits back into Siberia.

More PNA ridging like the Euro is showing at day 10 is warm in a Nino pattern as Canada loses the cold

air supply. There will also be just enough ridging near the east coast to keep the temps above average.

 

attachicon.gifecmwf-ens_z500a_nhem_11.png

Look at the 850`s . There is ZERO WARMTH in Canada here .  That looks Normal and not above to me .

post-7472-0-96486100-1420302730_thumb.pn

post-7472-0-14299700-1420302743_thumb.pn

post-7472-0-09399200-1420302756_thumb.pn

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Thank you it seems we may have at least a shot at single digits. It's a plus that the coldest anomalies of this arctic shot are further east rather than over the Midwest but at the same time the lack of snow cover means temps could only drop so low.

In 2008 it occurred in February which ended up fairly normal with a good storm on the 22nd

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Those 850's are warm for January. You have to use the Euro ensemble temperature departures chart to get the right idea.

 

attachicon.gifecmwf-ens_T850a_namer_11.png

Yes but you have to realize " warm departures " in Canada with a POS PNA is not above normal at KNYC .

Minus 10 air at 850 in Manitoba may be plus 5 C from Normal but you slide that south with a POS PNA and no SE ridge ( the euro sticks a trough in the SE ) day 12 the 15 those HPs slip through the lakes and keep you normal.

You saw that Dec 2 thru 20.

Splits are 38 28 now. A degree either side of that will not feel warm

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