January Medium/Long Range: A snowy January ahead?

[wxmvpete]

2 minutes ago, wxmvpete said:

A little bit of a break down from the 12Z and 18Z guidance. The main discrepancy remains the strength/tilt of the 500mb trough, although the ridging along the West Coast feature differences too. Using 12Z Sunday as the time of interest, the ECMWF/CMC are most bullish on the 500mb trough while the GFS/ICON are weaker and more positively tilted in the 500mb comparison loop. This is also playing a big role in the strength of the emerging LLJ that is drawing up GoM moisture. Guidance like the ECMWF/UKMET/CMC are a little slower and not only generally deeper, but also positioned at a more neutral tilt. The GFS/ICON are more positively tilted and weaker in general. This has ramifications with the LLJ (850mb heights and winds comparison loop) as the strong SWrly flow shown on the ECMWF/CMC/UKMET yields not only more moisture/QPF, but a strong frontogentical component as well. Now one caveat is watching the 500mb trough over Lake Superior and western Ontario. That feature, should it make it far enough south and trend stronger, could act to suppress the tilt of the 500mb trough in the Plains and Mid-South on Sunday. Should that happen we would see not only a flatter system, but the moisture source is directed out of the WSW more and yields weaker 850mb FGEN. That can be give an take though, right? Seeing the 18Z ECMWF for example, it has a 70kt 850mb jet over northern AL. While that aids in exceptional moisture transport, that warm nose would also be a problem and make ice a bigger story than snow. This setup would be an exceptional FGEN maker, but at dry slotting would be a problem as the upper trough got closer. 

The NAEFS (last image) shows that even the GEFS/GEPS situational awareness tool shows exceptional moisture transport. That could be a sign of potential trends to come inside of 60 hours, because if that kind of moisture transport exists and more instability can come to fruition, that could sharpen up that IVT more at the Mid-Atlantic. Now most of it is oriented at the Southeast, but should the 500mb trough in the Plains trend stronger in the coming days, that orientation could lead to a better plume of moisture and more QPF to work with. On the flip side, this could cause more ice in parts of the VA Piedmont. Remember the ECMWF is the stronger outlier at the moment, and while the GFS and ICON may be not most folks cup of tea, it is what could happen if this system trends weaker.

Lastly, I wanted to share the differences at 500mb from the 18Z GEFS vs the 12Z GEFS. We're still seeing some notable changes just 36 hours into the period, even before the Pacific disturbance arrives. While its becoming more likely we are seeing in some capacity a measurable snow event, these changes on an ensemble still show there's much more to resolve.

To see the Probabilistic Winter Storm Severity Index (WSSI-P) showing moderate-to-high chances (50-70%) for most Minor Impacts for most on this forum should instill some confidence that we're dealing with a disruptive event Sunday night into Monday. It's a good signal for 4-5 days out on this product that we generate at WPC. 

[mitchnick]

8 minutes ago, wxmvpete said:

A little bit of a break down from the 12Z and 18Z guidance. The main discrepancy remains the strength/tilt of the 500mb trough, although the ridging along the West Coast feature differences too. Using 12Z Sunday as the time of interest, the ECMWF/CMC are most bullish on the 500mb trough while the GFS/ICON are weaker and more positively tilted in the 500mb comparison loop. This is also playing a big role in the strength of the emerging LLJ that is drawing up GoM moisture. Guidance like the ECMWF/UKMET/CMC are a little slower and not only generally deeper, but also positioned at a more neutral tilt. The GFS/ICON are more positively tilted and weaker in general. This has ramifications with the LLJ (850mb heights and winds comparison loop) as the strong SWrly flow shown on the ECMWF/CMC/UKMET yields not only more moisture/QPF, but a strong frontogentical component as well. Now one caveat is watching the 500mb trough over Lake Superior and western Ontario. That feature, should it make it far enough south and trend stronger, could act to suppress the tilt of the 500mb trough in the Plains and Mid-South on Sunday. Should that happen we would see not only a flatter system, but the moisture source is directed out of the WSW more and yields weaker 850mb FGEN. That can be give an take though, right? Seeing the 18Z ECMWF for example, it has a 70kt 850mb jet over northern AL. While that aids in exceptional moisture transport, that warm nose would also be a problem and make ice a bigger story than snow. This setup would be an exceptional FGEN maker, but at dry slotting would be a problem as the upper trough got closer. 

The NAEFS (last image) shows that even the GEFS/GEPS situational awareness tool shows exceptional moisture transport. That could be a sign of potential trends to come inside of 60 hours, because if that kind of moisture transport exists and more instability can come to fruition, that could sharpen up that IVT more at the Mid-Atlantic. Now most of it is oriented at the Southeast, but should the 500mb trough in the Plains trend stronger in the coming days, that orientation could lead to a better plume of moisture and more QPF to work with. On the flip side, this could cause more ice in parts of the VA Piedmont. Remember the ECMWF is the stronger outlier at the moment, and while the GFS and ICON may be not most folks cup of tea, it is what could happen if this system trends weaker.

Lastly, I wanted to share the differences at 500mb from the 18Z GEFS vs the 12Z GEFS. We're still seeing some notable changes just 36 hours into the period, even before the Pacific disturbance arrives. While its becoming more likely we are seeing in some capacity a measurable snow event, these changes on an ensemble still show there's much more to resolve.

You should have a redder tag.

[Deck Pic]

2 minutes ago, RVAman said:

Ah yes, let’s financially pick up my families life to move to somewhere north for snow when historically Richmond has bode well for snow besides the last 5-6 years? Makes a lot of sense. Just because someone tracks snow as a hobby and wishes it happens doesn’t mean they should move. What a delusional comment. Don’t get 25+ per season? Move to Buffalo? 

my point was your climo is your climo.  I'm like in the 4th percentile of this forum in terms of snow.  Model runs are just a simulation.  It snows where it snows.  Plus don't take it out on DC.  If you have to act out, take it out on the people who live in Carroll County.

[H2O]

2 minutes ago, stormtracker said:

I mean..here's the thing.   It's model spray and we're kinda in the middle at this point.   I'm not mad at that.

0z could have suppression from hell or conversely a Daniel Jones level confluence and we will be saying Congrats Carbondale.  But it doesn't instill much confidence when run to run jump of 80-100 miles takes place.  And the introduction of mixed enters the fray.  I ain't panicked but can't say I like this jump.  Is it a blip?  Gotta wait and see.  Pepperridge Farms remembers when its better to see jack zone in Columbia SC 5 days out. 

[BristowWx]

Just now, RVAman said:

Resulting to drugs to comfort yourself? Hmmm. 

Why are you so upset?  This could easily shift south.  Just have fun with it.  We are all friends here.  Oh and go Commanders!  That was for Randy.  

[wxmvpete]

6 minutes ago, HighStakes said:

If anyone is lucky enough to get 6-8 inches of snow with a solid coating of ice that would be incredible.  With the post storm cold and other storm chances there would be snow cover for the entire month of January. Who could complain about that?

^This. There's been one instance in wake of the 2016 blizzard (January 2019 from what I see on xm-ACIS) when Dulles exceeded Winter Storm Warning criteria. To get that event in any capacity would be a win for snow lovers (like me hah).

[RVAman]

Just now, BristowWx said:

Why are you so upset?  This could easily shift south.  Just have fun with it.  We are all friends here.  Oh and go Commanders!  That was for Randy.  

I’m not upset. I apologize if I came across that way. The frustration comes from Richmond constantly experiencing getting fringed. I hope you guys understand that. We are thirsty down here. Our climo used to be decent and recently it’s gone down hill. Didn’t mean to attack anyone or come across as bitter. The shift north on the euro isn’t good for us or NOVA because it seems as if it starts that movement it keeps going. 

[stormtracker]

7 minutes ago, mitchnick said:

You should have a redder tag.

I'm going to create an ultra platinum tag for him.

[T. August]

18z panels. Definitely introduces some full-on misses to the north.

[wxmvpete]

4 minutes ago, stormtracker said:

I'm going to create an ultra platinum tag for him.

I don't get enough practice posting in here to see what is too much haha. I'll try to shorten my posts more!

[BristowWx]

We should be climo jealous of Jon Jon out in Davis, WV. bet he gets destroyed regardless of what happens to the rest of us.  2ft of powder and below 0.  Now that’s winter. 

[ravensrule]

Just now, wxmvpete said:

I don't get enough practice posting in here to see what is too much haha. I'll try to shorten my posts more!

They are actually great and extremely informative. Also it breaks it down nicely for us weenies. Please continue as much as possible. 

[Paleocene]

Just now, wxmvpete said:

I don't get enough practice posting in here to see what is too much haha. I'll try to shorten my posts more!

Don't shorten the posts! Many of us are eager to learn more.

[WVclimo]

3 minutes ago, T. August said:

18z panels

49/50 give my yard at least 2+”. Don’t know if I’ve ever seen that high a percentage on an ensemble at these leads.

[mitchnick]

4 minutes ago, T. August said:

18z panels. Definitely introduces some full-on misses to the north.

Mean

[Interstate]

Can we stop with the bickering and banter 

[Weather Will]

WB 18Z EPS probs.

[Solution Man]

24 minutes ago, Deck Pic said:

It's actually kinda is.

It is

[H2O]

1 minute ago, wxmvpete said:

I don't get enough practice posting in here to see what is too much haha. I'll try to shorten my posts more!

Post long, short, medium, or extra long.  Just post cause we need more smart people posting and less dumb(myself included in that group)

[BristowWx]

4 minutes ago, T. August said:

18z panels. Definitely introduces some full-on misses to the north.

47 looks like a real winner.  Damn. 

[Terpeast]

Just now, mitchnick said:

Mean

Looks like a classic N+W event we used to get a lot in the past. I’d take it as long it doesn’t keep trending north (which is still a possibility)

[Solution Man]

4 minutes ago, wxmvpete said:

I don't get enough practice posting in here to see what is too much haha. I'll try to shorten my posts more!

Keep em coming, great post

[mitchnick]

3 minutes ago, wxmvpete said:

I don't get enough practice posting in here to see what is too much haha. I'll try to shorten my posts more!

Keep it coming man. Not that other red taggers haven't done it since, but your discussion brought me back to 12/09 & 2/10 when CoastalWx came into the Mid Atlantic thread on Eastern before those storms and talked dirty about both impending blizzards.

[BristowWx]

Ice would be fun.  Maybe we get that if temps stay below 28 or so.  Ice storm warning sounds ominous. 

[Terpeast]

Just now getting a chance to sit down and dig in, but @wxmvpete already did his excellent writeup. I don’t have much to add. Keep it coming! 

[Weather Will]

WB latest EPS extended, fun times ahead, below normal temps and normal to above normal precip.  Just need some luck.. 

[SnowenOutThere]

5 minutes ago, BristowWx said:

Ice would be fun.  Maybe we get that if temps stay below 28 or so.  Ice storm warning sounds ominous. 

Would be nice if @NorthArlington101 (or any other person who paid for model runs) could post the freezing rain/sleet accumulation maps

[Maestrobjwa]

4 minutes ago, wxmvpete said:

I don't get enough practice posting in here to see what is too much haha. I'll try to shorten my posts more!

Sir that was an excellent post (now I'm just an amateur at this, so take that for what you will, lol). Would love to hear your insights more! In a sea of emotional weenies one more knowledgeable voice wouldn't hurt 

[frd]

1 minute ago, Weather Will said:

WB latest EPS extended, fun times ahead, below normal temps and normal to above normal precip.  Just need some luck.. 

 

This extended period of cold and snow oppurtunities was discussed today by BAMM WX.  

Appears that Canada will reload later in the month with additional cross polar flow.  
 

 

[NorthArlington101]

2 minutes ago, SnowenOutThere said:

Would be nice if @NorthArlington101 (or any other person who paid for model runs) could post the freezing rain/sleet accumulation maps

I posted the sounding earlier… I think it’s really all sleet despite what this says, but who am I to question WxBell. It also dumps almost all of this in 3 hours. Don’t think it would accrete as much as help glaciate anything.