February Pattern and Storm Discussion

[WilkesboroDude]

Well it as obvious as seeing your hand in front of your face. The last ditch effort to get winter weather is upon us now. With overwhelming confidence there is almost zero chance of winter weather east of the apps until valentines day. The hope for a valentines day SE snowstorm are being dashed by models as what's in all likelihood going to be a apps runner. Climo wise that leaves most of us with about 3 good weeks left outside of the mountains or a freak March 1960 redux. Right now it looks like model wise the best bet is to keep hope alive because after the apps runner on valentines day , the cold will be coming gangbusters. The question is will it be able to hang around long enough to hook up with some moisture and/or will there be some moisture ( southern stream) available. The entire winter has been dominated by one stream ( i.e. no split flow) and no blocking setup to keep the cold locked in. Will folks who have seen nada for going on 2 years be able to break out of the slump? Will wow be able to show back up and post the phrase made famous in early December " GLORY " and see it actually unfold. Will GAWX who warned us for the past 2 months to watch out for Lucy, see a much below normal March unfold only to deliver 35 degree rainstorms because climo will have won out? Stay tuned and look at the bright side. We just got through 2 of the warmest winters in the last 118 years ( see wx south write up today), next year has to get better because it can't get any worse, right?

 

Still far from a last ditch effort in our area. There is nothing freak at all to get winter weather east of the mountains in March. The recent crappy winters have produced the March tokens we are wanting...for some at least. Something to watch.

[GaWx]

are these the same weeklies that about 3 weeks ago showed  a 4 week cold spell coming to the Southeast? I think Euro has been horrible this year. GFS not that great, but it did sniff out a big western ridge first and that worked out (which ended up producing the Upper low/thundersnow and the clipper regime).

edit to add :  but the cold hasn't really penetrated much past TN/NC line all season thus far. I've noticed each of the 3 last cold spells have shunted more east than south in the preceding few days, so we'll see if the deep south finally can turn cold, or if the current pattern holds sway all Winter.

 

Robert,

 Clearly, the Euro weeklies have not been consistently good overall although they did pretty well for Dec. with their warm forecasts. They were pretty bad in early Jan. when they were predicting a below normal (though not severely cold) late Jan/early Feb. to which you alluded. Also, the Euro does have at least a slight warm bias. Yeah, the GFS also hasn't been good and it has rushed colder changes many times this winter. I'm leaning toward it rushing the colder pattern eastward too quickly. I'm basing this on a combo of the cold GFS bias, especially during the 11-15, as well as Dec./Jan. analogs that were quite warm in Atlanta and had warmth dominate much of the SE US. These warm analogs suggest no sustained cold is likely for the bulk of the SE US at least til late Feb. and that March has a good bit better than average chance to be chilly.

[dsaur]

are these the same weeklies that about 3 weeks ago showed  a 4 week cold spell coming to the Southeast? I think Euro has been horrible this year. GFS not that great, but it did sniff out a big western ridge first and that worked out (which ended up producing the Upper low/thundersnow and the clipper regime).

edit to add :  but the cold hasn't really penetrated much past TN/NC line all season thus far. I've noticed each of the 3 last cold spells have shunted more east than south in the preceding few days, so we'll see if the deep south finally can turn cold, or if the current pattern holds sway all Winter.

Hey, Robert!  Good to see ya.  The 18z, I noticed, brought the o line into Fla. 5 frames earlier today, lol.  To me that's a good sign since it hasn't had the 0 line down there at all until recently.  The Gfs had the snow for Ga. Sat. way back, so I'm more inclined to give Goofy some credence this go round.  If it's cold in two weeks down in Tallahassee, I'll give Goofy another shout out   It doesn't have to be cold cold, just some cold penetrating the state for a change, instead of the sideswipe, to get my vote T

[FoothillsNC]

Robert,

 Clearly, the Euro weeklies have not been consistently good overall although they did pretty well for Dec. with their warm forecasts. They were pretty bad in early Jan. when they were predicting a below normal (though not severely cold) late Jan/early Feb. to which you alluded. Also, the Euro does have at least a slight warm bias. Yeah, the GFS also hasn't been good and it has rushed colder changes many times this winter. I'm leaning toward it rushing the colder pattern eastward too quickly. I'm basing this on a combo of the cold GFS bias, especially during the 11-15, as well as Dec./Jan. analogs that were quite warm in Atlanta and had warmth dominate much of the SE US. These warm analogs suggest no sustained cold is likely for the bulk of the SE US at least til late Feb. and that March has a good bit better than average chance to be chilly.

I dont see the Euro weeklies, other than what I read on various sites. So I can't really negate them. But the operational through day 10 and ensembles have certainly left a lot to be desired, other than the warm period in December. Since the pattern change in Jan 17 to 20, they have been off from what I read, and the operational has changed  almost every run drastically on days  7 - 10.  So the GFS days 11-16 are about the same as Euro days 7 -10 in my opinion, and the operational has caved almost every time on big events at that time frame (except Sandy, which is a big score).. So I'm not giving the weeklies that much credibility yet until it really redeems itself. Its been pretty warm south of TN/NC line and goes quickly colder in this pattern versus the older pattern where everyone was warm in Dec, to mid jan.

So I'd be suprised if the Euro weeklies don't change it's tune soon to match the last few days of GFS runs...showing a big western ridge/central-eastern trough). This base just  on the fact that the GFS pretty much nailed the development of the western ridge 2 weeks in advance, but was a few days too fast for the eastern effects, and it still overdoes the cold south of Tn/NC areas. At some point though, the Gulf will probably get hit with cold and this may be the one. Or you may be right in it holding off til March. Who knows.

[franklin NCwx]

Robert there is a big battle going on off the new England coast between the gfs and euro. Euro is phasing the two streams while the gfs is dr no! Like you said we have seen this song and dance a few times this year and other than sandy. The gfs has beaten the euro.

[tnweathernut]

Robert there is a big battle going on off the new England coast between the gfs and euro. Euro is phasing the two streams while the gfs is dr no! Like you said we have seen this song and dance a few times this year and other than sandy. The gfs has beaten the euro.

I have been wondering how a storm blowing up on the northeast coast affects the long range. (Similar to the Ukie or Euro). Is this of minimal importance to the long range or fairly significant? My guess is that the bigger feature we want to see is the nice ridging into Alaska. If we get that we can then look for any features that may become a 50/50.

[DixieBlizzard]

I have been wondering how a storm blowing up on the northeast coast affects the long range. (Similar to the Ukie or Euro). Is this of minimal importance to the long range or fairly significant? My guess is that the bigger feature we want to see is the nice ridging into Alaska. If we get that we can then look for any features that may become a 50/50.

...and while we are dreaming let's add a big ol' Rex Block ridging toward Greenland.

[tnweathernut]

...and while we are dreaming let's add a big ol' Rex Block ridging toward Greenland.

If I were dreaming I wouldn't care about features, I'd just drop consecutive 20" storms on my house and the entire southeast over a 5 day period.

On topic.........it's not necessarily a dream when the ridging is on multiple ensembles. haha

[DixieBlizzard]

If I were dreaming I wouldn't care about features, I'd just drop consecutive 20" storms on my house and the entire southeast over a 5 day period.

On topic.........it's not necessarily a dream when the ridging is on multiple ensembles. haha

 

I hope you didn't take that wrong because I meant if "I" was dreaming. You had a good post but I don't have the expertise to answer you more straightforward but what you said makes perfect sense to me. Does that make sense? LOL! I'd take the 22" if I were dreaming too!

[franklin NCwx]

If I were dreaming I wouldn't care about features, I'd just drop consecutive 20" storms on my house and the entire southeast over a 5 day period.

On topic.........it's not necessarily a dream when the ridging is on multiple ensembles. haha

seems like the ridging is on all the ensembles but the position is different. From what I gathered on the 10-15 day euro ensembles the ridge is much farther west than the gefs. Thus the difference downstream is huge. Its either a cold dump into the plains/west or the plains/east. Again, we still have no blocking so these storms can cut.

[superjames1992]

If I were dreaming I wouldn't care about features, I'd just drop consecutive 20" storms on my house and the entire southeast over a 5 day period.

On topic.........it's not necessarily a dream when the ridging is on multiple ensembles. haha

 

If we're dreaming, let's just move the three Mid-Atlantic Smowmaggedon storms of 2009-2010 another 200-300 miles south and call it a day. 

[tnweathernut]

I hope you didn't take that wrong because I meant if "I" was dreaming. You had a good post but I don't have the expertise to answer you more straightforward but what you said makes perfect sense to me. Does that make sense? LOL! I'd take the 22" if I were dreaming too!

No I didn't take it wrong. I hope my reply wasn't taken wrong. I just find it interesting that we usually want a storm like that to blow up as they will sometimes create the 50/50 low we need. I would think a storm blowing up like that would be good, but the Euro is the least favorable in the long run even though its the one blowing it up. Lets hope for the GFS ensembles to be closer to actual toward mid month. We really need that tall ridge out west.

[franklin NCwx]

No I didn't take it wrong. I hope my reply wasn't taken wrong. I just find it interesting that we usually want a storm like that to blow up as they will sometimes create the 50/50 low we need. I would think a storm blowing up like that would be good, but the Euro is the least favorable in the long run even though its the one blowing it up. Lets hope for the GFS ensembles to be closer to actual toward mid month. We really need that tall ridge out west.

I think the western ridge position has more to do with the mjo forecast from both models.

[WhiteoutWX]

I'd say the GFS and its ensembles look OK. The ridge out west is great but the flow across the US remains mostly zonal and fast. It would be hard to get a southern systemto develop and if one did it would have to be perfectly timed without significant blocking to keep colder air locked in place, much like the ice storm on the 25th. I'd say the pattern looks different but kind of the same as well.

[tnweathernut]

I'd say the GFS and its ensembles look OK. The ridge out west is great but the flow across the US remains mostly zonal and fast. It would be hard to get a southern systemto develop and if one did it would have to be perfectly timed without significant blocking to keep colder air locked in place, much like the ice storm on the 25th. I'd say the pattern looks different but kind of the same as well.

I would respectfully disagree. You don't see three wave patterns, a semblance of a split flow, and coast to coast troughs very often.

[WhiteoutWX]

I would respectfully disagree. You don't see three wave patterns, a semblance of a split flow, and coast to coast troughs very often.

The split flow has been off and on on the models I haven't seen a consistent signal one way or the other. The pattern is different I'm just saying the end results don't look all that different until we can get some blocking. IF the split flow can develop then I'd say it could get a little more interesting.

[valkhorn]

The long range looks good for East TN on the 00z GFS. Not a whole lot of snow, but prolonged chilly weather. If we have clippers pass through like we did last weekend (decent accumulating snows both days for Knoxville) then I won't be able to complain about this winter.

[NCSNOW]

6z GFS says a cold rain is coming up Friday in NC CAD areas. Gonna be a struggle to get to 40 imo. Hopefully the sun can make it out this weekend, because by late Sun going into Monday/Tuesday more rain is a coming. Then 2/13  all the way out is below normal in NC . The cold never penetrates deep south this run, kinda hangs up north of SC/NC border again like it has all winter when it does make an occasional appearance.

 

[calculus1]

6z GFS says a cold rain is coming up Friday in NC CAD areas. Gonna be a struggle to get to 40 imo. Hopefully the sun can make it out this weekend, because by late Sun going into Monday/Tuesday more rain is a coming. Then 2/13  all the way out is below normal in NC . The cold never penetrates deep south this run, kinda hangs up north of SC/NC border again like it has all winter when it does make an occasional appearance.

 

Yep, we finally get a beautiful Miller A setup...but, it's going to be too warm to get any wintry precip out of it here in the South.  Track of low is right along the gulf and up along the east coast before bringing some potentially nice snows to the NE.

[Tacoma]

Yep, we finally get a beautiful Miller A setup...but, it's going to be too warm to get any wintry precip out of it here in the South.  Track of low is right along the gulf and up along the east coast before bringing some potentially nice snows to the NE.

if this is a miller A setup wouldn't the storm as it rounds the bin just south and east of us pull the cold air from the northeast into the storm and change the rain to snow across nc and va and east tn?

[Cold Rain]

if this is a miller A setup wouldn't the storm as it rounds the bin just south and east of us pull the cold air from the northeast into the storm and change the rain to snow across nc and va and east tn?

That has a lot to do with how strong the storm is and how much cold is available to be tapped.

In any case, both the 0Z and the 6Z look good at the end of their runs, especially the 6Z. Big -NAO block, 50/50 low and a split flow. Would be really nice to see something like that in the near term.

[Tacoma]

That has a lot to do with how strong the storm is and how much cold is available to be tapped.

In any case, both the 0Z and the 6Z look good at the end of their runs, especially the 6Z. Big -NAO block, 50/50 low and a split flow. Would be really nice to see something like that in the near term.

Thanks,   if this storm is strong enough couldn't it produce its own cold air and if its that strong pull the cold from the northeast?

[tarheelwx]

I'm more interested in the CAD showing up on the Euro last night at 72hrs.  Check out the very strong hp over se canada ridging down east of the mountains.  Does anyone have surface temps for the 00z Euro at 72 hours?  This could be really close, especially if you take into account how the models underperformed the event a couple of weeks ago.  If the cold air is in place at the beginning, this has the potential to be wall to wall freezing/frozen for some areas.  Again, I haven't seen surface temps so all this may just be garbage.

TW

[Cold Rain]

Thanks, if this storm is strong enough couldn't it produce its own cold air and if its that strong pull the cold from the northeast?

Yeah, it could, but again, it depends on things like where it strengthens, how rapidly, the track and how much cold is available. I haven't looked at those things too closely today, so I don't really know if any of that is on the table with this storm. What you'd like to see with a strengthening Low taking a favorable track is an Arctic High to the north or northwest, funneling in cold air. If you don't see that feature, then that is a huge red flag against a widespread winter storm.

[Cold Rain]

I'm more interested in the CAD showing up on the Euro last night at 72hrs. Check out the very strong hp over se canada ridging down east of the mountains. Does anyone have surface temps for the 00z Euro at 72 hours? This could be really close, especially if you take into account how the models underperformed the event a couple of weeks ago. If the cold air is in place at the beginning, this has the potential to be wall to wall freezing/frozen for some areas. Again, I haven't seen surface temps so all this may just be garbage.

TW

I've been watching this for a couple of days now. That high pretty much stays in place and actually strengthens. You can see on the Euro that it sees the wedging. I haven't looked at surface temps or wet bulbs though. I can only assume that they must be solidly above freezing for most areas because no mets seem interested in this and all the local forecasts that I've seen show temps in the upper 40s or 50s.

Anytime I see a set-up like that, it piques my interest....although the High is a little farther north than I'd ideally like to see.

[tarheelwx]

I've been watching this for a couple of days now. That high pretty much stays in place and actually strengthens. You can see on the Euro that it sees the wedging. I haven't looked at surface temps or wet bulbs though. I can only assume that they must be solidly above freezing for most areas because no mets seem interested in this and all the local forecasts that I've seen show temps in the upper 40s or 50s.

Anytime I see a set-up like that, it piques my interest....although the High is a little farther north than I'd ideally like to see.

Totally agree.  HP does strengthen but it is in a reasonably good spot (ideally a bit further south).  00z GFS as it is has temps in the upper 30's in the triad.  If it were to show the same configuration as the 00z euro, then you would think that it might be pretty close.  Anyway, at least it is worth watching.

TW

[griteater]

Totally agree.  HP does strengthen but it is in a reasonably good spot (ideally a bit further south).  00z GFS as it is has temps in the upper 30's in the triad.  If it were to show the same configuration as the 00z euro, then you would think that it might be pretty close.  Anyway, at least it is worth watching.

TW

33-34 degrees with rain as close as Roanoke on 06z GFS.  Wedge signature is there, along with -20C 850mb temps in source region along U.S./ Canadian border.  1036mb parent high.  Weak, but moist southern stream wave.  Agree, something to watch.

[franklin NCwx]

Thanks,   if this storm is strong enough couldn't it produce its own cold air and if its that strong pull the cold from the northeast?

The one this week will be a cold rain. The one to start watching which could be a storm that cuts to our west would be the Valentine's day storm. Here is last nights euro run. If it would have kept one low and ran it up the coast it would have been good for us. Instead in runs one up to our west and one up the coast flooding us with warm air in the mid levels.

[packfan98]

We are approaching the 2-3 day time period where the models will get consistently colder for each run for about a 24-36 hour period in the CAD regions with this setup.  That would make this a close call for some in the CAD regions of NC/VA.  It doesn't look to be a major event this far south and a cold rain may be in order.  It does bear watching though.

[superjames1992]

Yeah, it could, but again, it depends on things like where it strengthens, how rapidly, the track and how much cold is available. I haven't looked at those things too closely today, so I don't really know if any of that is on the table with this storm. What you'd like to see with a strengthening Low taking a favorable track is an Arctic High to the north or northwest, funneling in cold air. If you don't see that feature, then that is a huge red flag against a widespread winter storm.

 

We made due with the March 2nd-3rd, 2010 storm with only a weak 1026 mb HP in place up in Manitoba.  Of course, that was also a very strong storm at 996 mb off the coast of ILM and we fought with boundary layer temps quite a bit (though it was all snow here, at least, though a wet one with temps ranging from 33-35).  That was in March, too.  It's obviously not ideal, though.

 

 

EDIT: I don't have the map,  but I also don't recall a strong HP being in place before the 2000 Carolina Crusher.  I might be wrong, though.