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Everything posted by tombo82685

  1. This is how you can possibly get it done for something next weekend. GFS illustrates how it can work So first off, we have an expansive block across the top. We can see the low heights into Alaska which is bringing in pac puke underneath the block. We have a split flow out west with a big closed low sitting off the Baja. Downstream this will try and pop a se ridge ahead of any shortwave ejecting out. Underneath the block and north of the great lakes we have a legit, albeit brief, cold airmass that originates from the nw territories. So there is our fresh cold airmass. We then have a strong piece of energy that came off the big closed low off the baja, this piece of energy is over new mexico. We also have a large 50/50 low that is helping to suppress height rises from the diggign energy in the southwest and off the baja Next time period, we still have our alaskan trough which is bringing the pac puke in. We have are expansive block across the top holding in 50/50 lows. We still have out closed low trough sitting off baja trying to initiate a se ridge. The brief cold shot from the nw territories is swinging through the northeast with a good cold airmass. This is helping to fight off any height rises trying to occur in response to the strong piece of energy in the sourthern plains. You can see if the -nao wasn't there this storm would be a cutter all the way as the heights out ahead of this want to rise. The closed low swinging acrss the northeast is supressing the heights along the east coast and that will act as our new 50/50 low caught under the block. We also have a decent ridge spike along the west coast. It's not in a good spot for a snow track as it would argue for a storm to cut. With the 50/50 low caught underneath the block it will force the low to the south of it and not allow it to cut to the north. We can see the main players now, block across the top. Big 50/50 low caught underneath the block suppressing heights preventing the low ejecting out of the southern plains from cutting to the lakes. Key is timing the energy ejecting out with the low swinging through the lakes. Closer together they are, better chance the storm ejecting out stays underneath us. If the 50/50 low gets way out ahead of this, we will lose our cold airmass as pac puke is waiting to eject in. It will also give a pathway for the low ejecting out of the plains to come west too. In general, it's a period of interest. Chances aren't great right now, but it's not a 0%. If we had a more expansive area of cold and not pac puke waiting to eject in, I would be a bit more optimistic. The chance is there, and this is how you can get it done.
  2. Yup, -nao is good for some monsters. Best tandem is -nao and +pna. But if I had one or the other I’d take +pna. With that you know the cold is there. You can get some good miller A’s with it too. You can also get dry and cold too. With -nao you can still be warm if the pacific pattern doesn’t cooperate. So while you may get big storms, it may not be cold enough for snow. Also you can get cold and dry with -nao too
  3. Also, I'm selling hard on both these RMM forecasts of the curl back. I can see the tropical wave weakening a bit as it comes into the IO due to the cold waters there, but it should restrengthen again in phase 3. This wave should progress through warmer phases IMO despite what these RMM plots show with the noise associated within them
  4. Also remember, just because you have blue on the map over you, doesn't guarantee its below normal temps. It could just be signally areas where low pressure/storminess may be. Same goes for the warmer colors. Like for instance, the last map i posted abaove, the yellow colors near the davis straits. One would think, ridging there. Thats actually incorrect, there is a trough there, but the heights within the trough are just higher than normal so it gives the warmer colors
  5. Now we look at the eps around same period. Has the -epo look as well which is why I can see that airmass around Thanksgiving trending a bit colder. But they then disapate that ridge and swing the trough back into Alaska, which would then jump start the pac invasion again
  6. GEFS are certainly better. After the pac puke late next weekend into early following week with the below normal hgts over AK. They build a decent -epo look which cools down western Canada and starts sending some legit airmasses south. Ridge out west is to far west for my liking and supports se ridge, but with the -nao look we keep it in check. Thats why I saiud last night, if we lose the -nao you can see where we go with where the ridging is out west.
  7. Part of the issue too, look at the pacific jet, aimed right at Canada. Also has a bit of a jet extension in extended range on eps. This keeps western canada warmer than normal, so the airmass coming from there aren't as cold as one would think because of Pacific influence. Again, this is just what the eps show
  8. The cold shot next weekend is a decent airmass that comes down from the nw territories. It's brief, but a good cold shot. After that, atleast on the eps, it's below normal temps but nothing earth shattering like we had this week. I could see the day before Thanksgiving and Thanksgiving itself trending a bit colder. Decent cold look at 850.
  9. Also, euro starting to show the big time warming from wave 1 hit starting to work over pole by day 10
  10. Just going off the image you posted, but the eps are slightly below normal. Not that cold at all really. You can thank the pacific slop everywhere prior to this period with the low hgts over Alaska. Can see the flow is straight off the Pacific, then that comes east and is blocked in from the -nao
  11. All I see are pre 6pm sunsets as far as the eye can see
  12. If we could just get that pacific ridge further east, man that would be a pattern and a half on the WEFS
  13. If you had a +pna you wouldn’t have a se ridge. So since we don’t have a legit pos pna the nao is helping to keep se ridge at bay.
  14. Yes it is certainly helping, but we need some improvement in the pacific if we want to start looking for wintry precip events. The airmass is just not going to cut it this time of year outside elevation areas. Unless we can time something just right with a fresh airmass. In general though, for big storms I agree -nao is key, but overall pacific trumps the atlantic. Our weather doesn't flow north to south, it goes West to east . There have been numerous times where we have had a -nao and we were above normal temp wise because the pacific didn't cooperate.
  15. people will debate this with me but I’ll take a +pna over -nao anyday. For big storms -nao is good but outside of that, meh
  16. Problem I'm seeing is even though we have a -nao what are we blocking here? Looks like all pacific slop
  17. if we can pop a -nao and have a decent looking pacific that can transport a legit airmass instead of pac puke, next weekend has a bit of a chance. If we don't get the pacific help, I don't see much in the next 15 days.
  18. Just looking at the ensembles here, They all agree on the split flow. The pacific h5 look on the geps and eps support a trough in the plains/rockies with some se ridging into the east. The main ridge axis on those models is off the west coast, not good for the east. This is a direct result of where the trough is in the north pacific, it's not over the Aleutians but it's more dateline centered and not that amplified. So the trough into the southwest makes sense from an h5 look plus with the flatter trough look in the north pacific it creates more zonal flow. The gefs are the coldest looking, with a bit more favorable pacific look. The trough in the pacific is a bit further east and more amplified than the other two. This really pumps the ridge up into northern canada and into Alaska, so we get a solid cold air source. What it really comes down to is the -nao. The gefs and geps are bullish on this which is probably the main reason for the lower hgts in the east. Combine the -nao and +pna look on the gefs and yea that would be a cold stormy extended look. The geps are below normal, but they aren't as good with the pacific, flatter flow. So airmass is more pacific oriented and most of the cold air would dump to our west. The eps are the warmest of the guidance, no torch but not cold. They have no -nao, pacific pattern is very flat and zonal. IMO, the -nao is the wild card here, I'm not good enough to determine whether that is legit or not. ONce we get inside 7 days and it's there on all ensembles then we can say yea this happening. The nao is what holds the cards, if we get that then we get a cross between the geps and gefs. If the -nao isn't it's eps all the way. They make the most sense mjo wise. Just like last night I discounted them because of the deep trough they had and well they went towards my thoughts. By Thanksgiving we should be getting close to phase 2 of the mjo. Since we are like 3 days from December it would probably be best to use the December composites. Both phase 2 and 3 for December support are trough in the west, more so 3 than 2. So if the -nao fails to materializes the eps pattern would be my opinion where we go from Thanksgiving into December.
  19. The gefs are the only model grouping that goes ham with it. Euro is slower with it. Still has wave 1, but not to the magnitude of gefs. Also looks like a bottom up warming on euro
  20. Maybe best to apply westerly qbo-> easterly qbo effects to nino type background state. Because like 95 is not a good enso fit, not sure what 78 was. 02 isn't terrible but that was a much stronger nino
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