February/March 2020 Winter's Last Chance Thread

[TellicoWx]

53 minutes ago, Holston_River_Rambler said:

A little hesitant to post one EPS member, but 28 does a good job illustrating what a NW jump on the OP could do for even Chatt:

Just looked at the EPS...give me 28 and I will call it even for the past 5 winters with Mother Nature lol.

[Carvers Gap]

Several big hitters in the ensembles.  The overnight run of the EPS was again fairly chilly as was the operational.  There are a lot of BN temps beginning with tomorrow, especially compared to the last two months.  Will be interesting to see the MJO today.

[Carvers Gap]

MJO this morning looks very weak and trending away from the warm phases that we have been in for nearly two months - maybe a little longer.  Could easily be a head fake.  JB mentioned changing wavelengths this AM, but to be clear we have been on this for a couple of weeks...the wavelengths changing up are pretty much wrecking havoc on modeling.  I have said that this looks like November vs Phase 6 of the MJO as the modeling seems to be delivering every (5-6 days) substantial troughs moving into the East and warm-ups in between.  Again, this looks very much like what happened during the November cold snap.  Crazy warmth but when the wavelengths changed in November, the door was opened for colder air to enter the pattern.  When the wavelengths lengthened out during winter...warmth returned.  There are some pretty strong cold shots on most modeling - operationals and ensembles.  I hesitate to call it a pattern change as that phrase has worn thin.    We have had pattern changes.  I mean we have had the pattern that lasted from early December to mid-January.  Then we had the HB block w limited cold for the second half of January.  I think February is really not a well defined pattern at this point.  Had the big trough last week.  Now we have had the big ridge.  Going to get another big trough followed by another big ridge.  Seems like a ridge in the East pattern, but with a trough that loads and pushes it out...type of pattern.  What is on LR modeling is different.  Heights build over the top and trap cold underneath.  No idea if this happens, but I am pulling for the PV to get dislodged and trapped in NA as ridging builds over the top.   For those of you who are beginning outdoor sports, that is not what you want.  For those wanting some early spring snow...that is on my wishlist.  The EMON MJO is out today and it is null.  If the MJO is not driving the bus, I bet the -EPO takes over but w several storms that cut under the big eastern Pac ridge.  Again, modeling looks quite good today.  The great thing right now is that man of the changes are now well within 10 days as evidenced by the increasingly colder Euro operational and EPS.  The 10 day temps anomaly for west TN is now BN on the Euro operational, normal for middle TN, and slightly AN for E TN.  The 0z EPS 10d ensemble centered for d5-15 is normal with plenty of cold to balance the AN temp interludes.   Getting to the point now that from a tracking standpoint, we are going to pretty much have to eyeball most systems after the 18th.    Lastly, the cutoffs being handled better in the West are allowing more cold to penetrate eastward.  We thought that was fish...turns out it was.

[snowmaker]

Hopefully we will get one of them famous northwest trends, northwest middle tn would get shafted on that. That would be the ultimate downer if a good winter storm goes south of me at the end of winter. But good luck for all.

[PowellVolz]

Hopefully we will get one of them famous northwest trends, northwest middle tn would get shafted on that. That would be the ultimate downer if a good winter storm goes south of me at the end of winter. But good luck for all.

Just having a storm within 2 area codes is a win in my book.


.

[Carvers Gap]

Probably spoke too soon regarding problems in the Southwest.  12z GFS evolution in west TX does not look realistic beginning at 132.  I could be wrong, but I bet that kicks out in reality.

[snowmaker]

4 minutes ago, Carvers Gap said:

Probably spoke to soon regarding problems in the Southwest.  12z GFS evolution in west TX does not look realistic beginning at 132.  I could be wrong, but I bet that kicks out in reality.

I have lived in Tennessee my entire life and have always loved weather, I am not nearly as good at looking at maps and understanding them as most are in here. But I was thinking to myself earlier, that looks weird how it goes back west after getting so far east. Just looks odd. Kind of hard for me to think it would be raining in Tennessee with a 1047 HP in Iowa as well.

[Carvers Gap]

49 minutes ago, snowmaker said:

I have lived in Tennessee my entire life and have always loved weather, I am not nearly as good at looking at maps and understanding them as most are in here. But I was thinking to myself earlier, that looks weird how it goes back west after getting so far east. Just looks odd. Kind of hard for me to think it would be raining in Tennessee with a 1047 HP in Iowa as well.

Part of that is a low stuck in the Southwest that is spinning counter clockwise and pulling that precip shield from El Paso.  It can happen, but is very counterintuitive to me.  In general those type of lows have not been verifying in that manner.  It is definitely common for energy to come out in pieces or even the entire system.... In my experience, when systems seem to buck the flow, it is more in the Colorado front range in the spring.  Sometimes lows can pull precip northeast into Colorado.  The CMC has a more "acceptable"(not that the atmosphere asks me for approval....LOL) evolution of that pattern.  It ejects part of that system out, and the rest sort of sinks into Mexico and comes out as a storm later.  The interesting thing is that those systems in the Southwest usually come out.  JB used to call them "pay me now or pay me later" systems and sometimes calls them "money in the bank" systems.  I hesitate to say something can't happen as the weather can produce some wild phenomena that are within the bounds of physics.  But yeah, just looks wonky.  That is the second time I have seen that on modeling this winter.  One run had precip move from E TX into New Mexico.   So, really I am not sure that I trust that run from that point onward.  The run wasn't terrible...but that storm that comes out of west TX is another one of those storms that causes the rest of the pattern to pivot around it.  If that set-up is modeled incorrectly, rest of the run is likely off...and it might be off anyway knowing the GFS.  To me, that looks like a real chance at a winter storm with cold pressing over the top and energy which is likely going to come out.  The GFS almost has a storm at 144 and then backs off.  The CMC is a realistic look and rain.  Interesting timeframe and sitting around 132 with those monster highs.  The BIG problem is if it comes out as a gradient system and we are on the Southside of the gradient....flooding potential would be huge.  So, we really need those 1045+ highs to verify both for snow chances and just to reduce rainfall amounts.   They will at least squash the boundary enough - maybe.  

[Carvers Gap]

And right now that is sort of cold chasing rain around 132, but it is also big, cold highs which are not interacting with a very active weather pattern.  It has been very rare this winter for the active precip pattern to not interact with the cold.  Our problem has been that interaction has taken place well to our north...but plenty of interaction and snow has resulted there.  So color me a bit skeptical to see a big, 1045+ high press into the East and then see the active precip pattern not at least attack that cold.  Again, that has been going on all winter, but to our north.  My overall point, give me a big high like that and an active STJ...and let's see what happens.  

[Carvers Gap]

It is a bit of a hunch, but I think something runs that boundary around 132.  Now, it could easily go to Ohio.  IF that energy being stalled in the Southwest is incorrect, that energy could come out entirely or in pieces along a strong cold front boundary.  Not a given, but something to think about.  At worst, that energy comes out about 2-3 days later and heads for the EC.

[Carvers Gap]

No idea if this verifies...but a fun toggle is between 240 and anything after 300(NA view) of the 12z GEFS on Pivotal.  Both the EPS and GEFS have a pretty potent setup beginning to evolve right after d10.  Not going to give the usual caveats...everyone should know by now.  That said, the pattern that is showing up is ridging over the top with cold underneath.   That set-up will work even late in winter given that the event is at night and not middle of the day.

[TellicoWx]

1 hour ago, Carvers Gap said:

It is a bit of a hunch, but I think something runs that boundary around 132.  Now, it could easily go to Ohio.  IF that energy being stalled in the Southwest is incorrect, that energy could come out entirely or in pieces along a strong cold front boundary.  Not a given, but something to think about.  At worst, that energy comes out about 2-3 days later and heads for the EC.

Just depends on which is correct with the HP placement...GFS placement would suppress anything toward the gulf..12z Euro looks alot better than GFS so far

[TellicoWx]

GEFS isn't quite buying what the OP has as well...at this range everything looks decent.

[Carvers Gap]

4 minutes ago, TellicoWx said:

Just depends on which is correct with the HP placement...GFS placement would suppress anything toward the gulf..12z Euro looks alot better than GFS so far

12z Euro has a gradient winter storm in the South at 168.   Yeah, that looks good.

[Carvers Gap]

1046 high parked over the top of an active STJ...yep, we take.

[Carvers Gap]

That is a great set-up.  No idea if it stays that suppressed.  It might end up in Dayton, but that is a monster high.

[Carvers Gap]

This is the surface MSLP anomaly...

[Carvers Gap]

That is a 1057 high parked over northwest Colorado.

[Carvers Gap]

20 minutes ago, TellicoWx said:

Just depends on which is correct with the HP placement...GFS placement would suppress anything toward the gulf..12z Euro looks alot better than GFS so far

Any hunch as to which has the best HP placement?  Seems like model biases are backwards on this in terms of holding energy back as well.

[snowmaker]

By the looks of that we need just a little north trend and Tennessee would be in business. At 7-8 days out at least there may be a chance. Fingers crossed, it has potential if only we could get a little lucky for once.

[Holston_River_Rambler]

One of the things that really cool about the OPs look is that it has us on the right entrance region of a jet, just like it has for all these heavy rain events recently:

get that mega high and those dynamics. yum. 

[Holston_River_Rambler]

IMO that jet look is more believable than having a bowling ball at this range, since our current pattern has been conducive to that sort of a jet 

[Holston_River_Rambler]

ILMRoss a met in the SE thread has a good breakdown of the Euro, if interested. 

[Carvers Gap]

12z EPS is banging the drum for a good looking pattern - both the control and ensemble.   Sure looks like phase 8.  No idea how long it lasts, but we will take it if it verifies.  Cold look.  The control has a fairly strong cold shot with an isolated area of 30 degree BN departures over SW VA at the end of the run.  Considering that the EPS/Euro has missed a couple of cold fronts between the 10-20th at range, makes me wonder if the cold is underdone on the ensemble(control is plenty cold!).

[Mr Bob]

The weeklies have gone mad the next couple of weeks, also.....

[weathertree4u]

3 minutes ago, Mr Bob said:

The weeklies have gone mad the next couple of weeks, also.....

Meaning...

[TellicoWx]

1 hour ago, Carvers Gap said:

Any hunch as to which has the best HP placement?  Seems like model biases are backwards on this in terms of holding energy back as well.

Couple things I noticed on the 12z suites..the GFS has stronger ridging over the Gulf (which may be acting as a block for the SW ejecting out). On the water vapor you can also see how the GFS is pressing the HP far enough south (when combined with the stronger Gulf ridging) essentially shuts off any return flow and the Pac Jet. The Euro allows the Pac to also gain some moisture off the Gulf and ejects pieces of energy out ahead of the main SW, similar to what Holston was talking about with the previous setups over the last couple weeks.

[TellicoWx]

Overall I think there is fairly decent enough signals for some type of overrunning event in the Mid South. If a LP happens to pop on any piece of energy that ejects out ahead of the main piece...then it's a whole different ballgame.

[MJO812]

1 hour ago, Mr Bob said:

The weeklies have gone mad the next couple of weeks, also.....

?

[Holston_River_Rambler]

Don't want to put words in Mr Bob's mouth, but I think he was pointing out the weeklies look nice the next two weeks: