Pump the breaks Euro. Trending north a little too fast for my liking!
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Wintry February 19-21, 2020 Winter Storm
- Thread starter Six Mile Wx
- Start date
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Brick Tamland
Guest
And just like that the GFS says game on. This is why folks should not get and worry about so-called trends inside a 24 hour period. Anytime we have a threat of a winter storm it is a fluid situation, and the models are going to change and go back and forth this far out. They are still trying to figure things out. It's like a basketball game, sometimes it's a close one and the game goes back and forth. We were starting to lose on the models earlier today, but right now we're winning again.
And for folks in NC, you have to really like where the bullseye is on the GFS run when you consider it usually shifts NW the closer we get to the storm getting here.
And for folks in NC, you have to really like where the bullseye is on the GFS run when you consider it usually shifts NW the closer we get to the storm getting here.
Fountainguy97
Member
Y’all need to download “GIF-maker IMG play”. Or any free gif maker
It’ll make comparisons so much easier lol
It’ll make comparisons so much easier lol
While it’ll probably trend north some, I still like SC (including Columbia SC in this setup, gonna be hard to get this thing as far north as Central VA/DC like how are other ones have trended to due to the strength of that trough in SE Canada
whatalife
Moderator
You know how this works and the NW trend is all most a given in the SE. Sad but true.
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Dawgdaze22
Member
Good sign to see major increase out west toward Tx, La could be a sign of downstream effects for us here in Carolinas.
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Brick Tamland
Guest
I remember in the 80S when you could count on a storm in Texas coming to NC.
Jessy89
Member
Right now north Georgia looks good. But the trends are far from over. Don’t put stock into individual runs
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Webberweather53
Meteorologist
Here's my 2 cents on what I'm seeing atm w/ this potential overrunning event next week.
The difference between a storm and no storm late next week imo relies almost entirely on the orientation of the longwave trough centered over the Lakes - midwest - & into the south-central Rockies & Great Basin, not on whether we get the s/w out of the SW US to emerge from the Rockies, there's actually more than one way we can produce the solution we want here.
The reason we've lost the storm on the Euro is because this longwave trough has become increasingly positively tilted (from SW-NE to basically W-E) and the flow underneath it over the SE US has thus veered from the WSW in earlier runs to W-WNW in later suites. The reason for that has everything to do with the wave over the southwestern US lagging further behind and failing to pump the heights over the SE US and create W-WSWly mid level flow. Even if this wave continues to trend unfavorably, the other way we can get back to the snowier solutions on earlier runs and pump the heights in the SE US is if this northern stream wave over WI, MI, IA, & MN slows down and/or digs further west (say towards western IA, Nebraska, or the Dakotas instead). I think these desired changes are very doable inside day 5-6 and I wouldn't be shocked if our storm "came back" on the Euro/EPS in later runs.
When you compare the Euro & GFS 500mb vort around day 5, it's easy to see why one has a storm while the other doesn't.
Euro is much faster (& thus further SE) with the northern stream wave whereas the GFS slows it down & is less progressive for once (surprisingly). The GFS thus allows the heights to rise more over the SE US & therefore pushes the eventual sheared, overrunning wave further NW, bringing snow to parts of the deep south.
Even if you took both of these modeled patterns at face value, I'd still expect precipitation associated w/ said wave to be a bit stronger & further north than modeled due to aforementioned model biases wrt low-mid level warm advection. Stronger warm advection not only = stronger warm noses as we see time & time again, but if it's one of the primary forcing mechanisms (along w/ differential CVA) that's driving precipitation as it often is during overrunning events, this also means said precipitation will be more expansive in coverage and intense than forecast. Hence, I'm pretty skeptical of the suppressed solutions atm being offered by the ECMWF.
In any case, given the aforementioned discussion, it should be pretty obvious what trends we need to see the next few days to give much of the board a nice overrunning event:
Our longwave trough needs to be less positively tilted & the adjacent SE US ridge has to be stronger. Therefore, the evolution of both the northern & southern stream waves will be key here.
The difference between a storm and no storm late next week imo relies almost entirely on the orientation of the longwave trough centered over the Lakes - midwest - & into the south-central Rockies & Great Basin, not on whether we get the s/w out of the SW US to emerge from the Rockies, there's actually more than one way we can produce the solution we want here.
The reason we've lost the storm on the Euro is because this longwave trough has become increasingly positively tilted (from SW-NE to basically W-E) and the flow underneath it over the SE US has thus veered from the WSW in earlier runs to W-WNW in later suites. The reason for that has everything to do with the wave over the southwestern US lagging further behind and failing to pump the heights over the SE US and create W-WSWly mid level flow. Even if this wave continues to trend unfavorably, the other way we can get back to the snowier solutions on earlier runs and pump the heights in the SE US is if this northern stream wave over WI, MI, IA, & MN slows down and/or digs further west (say towards western IA, Nebraska, or the Dakotas instead). I think these desired changes are very doable inside day 5-6 and I wouldn't be shocked if our storm "came back" on the Euro/EPS in later runs.
When you compare the Euro & GFS 500mb vort around day 5, it's easy to see why one has a storm while the other doesn't.
Euro is much faster (& thus further SE) with the northern stream wave whereas the GFS slows it down & is less progressive for once (surprisingly). The GFS thus allows the heights to rise more over the SE US & therefore pushes the eventual sheared, overrunning wave further NW, bringing snow to parts of the deep south.
Even if you took both of these modeled patterns at face value, I'd still expect precipitation associated w/ said wave to be a bit stronger & further north than modeled due to aforementioned model biases wrt low-mid level warm advection. Stronger warm advection not only = stronger warm noses as we see time & time again, but if it's one of the primary forcing mechanisms (along w/ differential CVA) that's driving precipitation as it often is during overrunning events, this also means said precipitation will be more expansive in coverage and intense than forecast. Hence, I'm pretty skeptical of the suppressed solutions atm being offered by the ECMWF.
In any case, given the aforementioned discussion, it should be pretty obvious what trends we need to see the next few days to give much of the board a nice overrunning event:
Our longwave trough needs to be less positively tilted & the adjacent SE US ridge has to be stronger. Therefore, the evolution of both the northern & southern stream waves will be key here.
iGrey_X
Member
I’d say NE Georgia, upstate SC, the midlands through the piedmont of SC, up to the I40 corridor is NC is going to be the sweet spot for snow and higher accumulations.
Snowflowxxl
Member
Well Winters were actually cold back in the 80s....
Nothing better than logging on and wondering if the models were good and seeing you are on page 72 of 79 lol
bouncycorn
Meteorologist
There's a clear difference in the orientation of the STJ energy flow... even early on in the run. This difference begins around hour 120 and you can see the GFS orients the energy flow further north then the ECMWF. Going forward in the run, this orientation maintains it's latitudinal position until the shortwave pushes through around hour 150-156.
The overall flow direction is pretty similar between models. The ECMWF just keeps the fun stuff south whereas the GFS keeps it north. This difference appears to be due to a difference in blocking over the western CONUS during early next week. The ECMWF has much more blocking across the west where the GFS doesn't. This leads to the orientation shift of the energy flow.
Certainly not a classic setup. Quite rare we see things align like this. I wouldn't necessarily call the ECMWF solution "suppressed" as the HP over the eastern conus isn't the reason that precip doesn't fall further north, but I would expect that, even with the ecmwf solution, there would be more precip than progged further north.
The overall flow direction is pretty similar between models. The ECMWF just keeps the fun stuff south whereas the GFS keeps it north. This difference appears to be due to a difference in blocking over the western CONUS during early next week. The ECMWF has much more blocking across the west where the GFS doesn't. This leads to the orientation shift of the energy flow.
Certainly not a classic setup. Quite rare we see things align like this. I wouldn't necessarily call the ECMWF solution "suppressed" as the HP over the eastern conus isn't the reason that precip doesn't fall further north, but I would expect that, even with the ecmwf solution, there would be more precip than progged further north.
Iceagewhereartthou
Member
I'm hoping for one. While I don't mind CAE breaking the drought and seeing some snow, there's no part of me that wants to watch it get a foot while I see nothing (a la Jan 2000). Too bad we cant get a board wide or at least 85-20 bullseye storm.
2-3” of snow yes please. Ty for posting
Cash out now? Lol
pcbjr
Member
Six Mile Wx
Member
