February Pattern and Storm Discussion

[burgertime]

Ah ok, didn't know that.  Out of curiosity, why?  

 

Well it's not really science but often when the GFS gets closer the storm will take a more north western path. 

[NTriadwx]

Sorry.  I didn't know you needed a degree to drive the Google photo car.  

 

EDIT:  Oops.  I thought this was the banter thread. It's hard to tell sometimes.  Mods feel free to move this mini-conversation.

 

Yeah, you really shouldn't talk about something that you obviously have no idea about. There's a lot more involved with geography then you apparently realize.

[packbacker]

Euro doesn't even have the storm this run, at day 8 on the 0z run you could see a storm brewing in south Texas, on the 12z run, no storm.

[Cold Rain]

GFS has a bias of over-estimating the magnitude of cold air intrusions in the LR (something in the model physics), which leads to a general suppression of the storm track and squashing of energy which would produce storms. Although not always, quite frequently, you will see the magnitude of the cold diminish and storms more amped and farther north/west as you get closer to verification.

This is very common with this model in the winter months. For that reason, seeing a storm suppressed and squashing cold air in the LR is a good thing.

[HurricaneTracker]

Also GEM has this....would have to think that would be some major CAD possibly even creating a snow event if that high could stay there for a little while longer...

 

 

So the RGEM and GFS (and now the NAM (gasp!)) has been showing what I will call a pseudo-CAD event.  The parent cold high isn't ideally situated for an optimal CAD event.  The strength of the high 1036-1037mb is pretty decent, but it's ultimately its position that, to me, doesn't favor much frozen precip over the Piedmont or the mountains.  I'll post a few forecasting soundings in a second, but if we do manage to get a window of frozen precip, it should be short-lived as WAA wins out at the lower-middle levels of the atmosphere.

[Cold Rain]

Euro doesn't even have the storm this run, at day 8 on the 0z run you could see a storm brewing in south Texas, on the 12z run, no storm.

There's a shocker. How many snowstorms has the mighty Euro shown in the LR this year only to vanish them within the next run or two. Seems as bad as the GFS lately with that stuff.

[burgertime]

So the RGEM and GFS (and now the NAM (gasp!)) has been showing what I will call a pseudo-CAD event.  The parent cold high isn't ideally situated for an optimal CAD event.  The strength of the high 1036-1037mb is pretty decent, but it's ultimately its position that, to me, doesn't favor much frozen precip over the Piedmont or the mountains.  I'll post a few forecasting soundings in a second, but if we do manage to get a window of frozen precip, it should be short-lived as WAA wins out at the lower-middle levels of the atmosphere.

 

Ah OK, would the high be better suited in upstate NY to funnel in the colder Canadian air? I'm not an expert on CAD by any means. 

[GaWx]

12Z Euro very strong -NAO late in the run

[burgertime]

CMC has a good track but there is also another low bombing out around the lakes so it's too warm. 

 

[WilkesboroDude]

So the RGEM and GFS (and now the NAM (gasp!)) has been showing what I will call a pseudo-CAD event.  The parent cold high isn't ideally situated for an optimal CAD event.  The strength of the high 1036-1037mb is pretty decent, but it's ultimately its position that, to me, doesn't favor much frozen precip over the Piedmont or the mountains.  I'll post a few forecasting soundings in a second, but if we do manage to get a window of frozen precip, it should be short-lived as WAA wins out at the lower-middle levels of the atmosphere.

 

Unfortunately that window may be near Friday morning commute. 

 

Blacksburg

 

This system continues to be another one of several this month that have posed a precipitation type challenge to the forecast. Our latest thinking is that the southwest portion of the region will experience mainly rain through about midnight Thursday night. After midnight...there will be enough of a warm nose aloft so that the wintry weather will be primarily in the form of freezing rain or sleet once surface and boundary layer temperatures cool to below freezing. As the night progresses...the warm nose aloft will increase in strength while surface temperatures continue to cool below freezing. By Friday morning...most of the area is expected to have freezing rain with only the northeast section of the forecast area still have some sleet. Areas between Bluefield WV and Richlands Virginia may experience only rain through the night. They will be west of the cooler wedge and remain above freezing through the night. 

[burgertime]

Euro is pretty downright cold in the LR. 

[Brick Tamland]

There's a shocker. How many snowstorms has the mighty Euro shown in the LR this year only to vanish them within the next run or two. Seems as bad as the GFS lately with that stuff.

 

Still a long way to go. I'm sure it'll change many times between now and the end of the month.

[HurricaneTracker]

Alright, a few forecast soundings.  First from CLT for 12Z Friday morning (the first hour of total saturation).  All rain.

 

 

Now, CLT 24 hours later valid sunrise Saturday morning.  All rain.

 

 

Moving northwest into the mountains, here is the sounding for Asheville valid Friday morning.  All rain.

 

 

And finally for Boone, valid 09Z Friday morning.  Freezing rain, but it is transient - done by 18Z.

 

 

So, the final point being, this CAD scenario doesn't favor much winter weather beyond the far northern mountains, and even then, just for a few hours.

[SnowNiner]

12Z GFS Ensembles still on board for a great look beginning of March.  Is it me or is the +PNA getting sharper each run?  Not as good as the EURO had last night but pretty nice. 

 

[superjames1992]

The 12z GGEM op is weird for the early March system.  It's strange to see two LPs form simultaneously and one track into the Midwest and just stall out while bombing.  The Gulf Low looks like it tracks a little too far inland for my tastes, anyways, though.

 

That's a hell of a storm on the GGEM, though.  Moisture is in no short supply!

[packbacker]

There is a parade of cut-offs around the world that is clogging things up and not allowing that low over the lakes to get NE and become a 50/50, hopefully that trends better...

 

 

[GaWx]

Absolutely massive -NAO and very cold (records??) SE late in 12Z Euro 6-10.

[Srain]

I wouldn't get too worked up over any run to run volatility at this range. There will be changes and Winter Storm RECON has been tasked as well...

 

 

WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1045 AM EST WED 20 FEBRUARY 2013
SUBJECT: WINTER STORM PLAN OF THE DAY (WSPOD)
         VALID 21/1100Z TO 22/1100Z FEBRUARY 2013
         WSPOD NUMBER.....12-082

I.  ATLANTIC REQUIREMENTS
    1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
    2. OUTLOOK FOR SUCCEEDING DAY.....NEGATIVE.

II. PACIFIC REQUIREMENTS
    1. FLIGHT ONE -- NOAA 49 --
       A. P22/ DROP 6 (57.0N 178.0W)/ 22/0000Z
       B  NOAA9 15WSC TRACK22
       C. 21/1930Z
       D. 11 DROPS ON TRACK AS PUBLISHED
       E. 41,000 TO 45,000 FT/ 22/0600Z

    2. OUTLOOK FOR SUCCEEDING DAY: POSSIBLE TRACK 23
       A. P-23/ DROP 8 (47.0N 175.0W)/ 23/0000)
    3. REMARKS: TRACK P-14 MODIFIED WILL BE FLOWN
       TODAY AS DETAILED ON WSPOD 12-081 AMENDED.
 

[packbacker]

Thanks Srain!

 

The CPC Super Ens., looks fantabulous as do the analogs,  (cue:  Homer Simpson eating donut sound)....

 

[franklin NCwx]

That midweek storm needs to get out of the way. It just absorbs the follow up wave .it either needd to transfer to the coast or drift into the ne. The cmc solution is almost impossible.

[superjames1992]

I've seen the CPC Super Ensembles referenced a few times recently.  What are they exactly and are they typically accurate?

[franklin NCwx]

Lol at 93 showing up so much. Grear looking 5h map though.

[burgertime]

I personally like the look of the 12z Euro. While it doesn't have a huge storm (or any storm for that matter) at the surface in the LR it does have a lot of cold air. For me this is always the first step. 

[beanskip]

Ungodly early March cold outbreak per 12z Euro Days 9 and 10. If that verifies, stuff will die.

[packbacker]

I've seen the CPC Super Ensembles referenced a few times recently.  What are they exactly and are they typically accurate?

 

I always thought they were the GFS ensembles runs (mean) and it pulls in analogs that closely match it.  I see a lot of red taggers using it, so it's got to be somewhat useful.  I take a peak at them from time to time, I don't remember the last time they should favorable analogs, 2010 maybe.

[superjames1992]

I always thought they were the GFS ensembles runs (mean) and it pulls in analogs that closely match it.  I see a lot of red taggers using it, so it's got to be somewhat useful.  I take a peak at them from time to time, I don't remember the last time they should favorable analogs, 2010 maybe.

 

Ah, okay, that makes sense.  Thanks.

[packbacker]

I am not real excited on the Feb28/March 1st storm that has been showing up, probably the week after is a better chance, if the pattern holds.  We need that low over the lakes out of the way and all models are showing it rotting away around Feb28/March1st.

[griteater]

I personally like the look of the 12z Euro. While it doesn't have a huge storm (or any storm for that matter) at the surface in the LR it does have a lot of cold air. For me this is always the first step. 

 

I'm with you Burger.  This is a cold, but dry look....but I would always prefer to take my chances with cold air in my pocket...we'll see if it holds.

 

Rather blocky would you say?

 

 

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[packbacker]

I'm with you Burger.  This is a cold, but dry look....but I would always prefer to take my chances with cold air in my pocket...we'll see if it holds.

 

Rather blocky would you say?

 

 

 

Why dry?  Just because it's not showing a storm or because of the ridge axis placement in the west?  The ridge axis looks good to me, I don't want it any further east, that would definitely blow.

[griteater]

I always thought they were the GFS ensembles runs (mean) and it pulls in analogs that closely match it.  I see a lot of red taggers using it, so it's got to be somewhat useful.  I take a peak at them from time to time, I don't remember the last time they should favorable analogs, 2010 maybe.

 

I've been wanting to find out myself, but yeah, I believe the superensemble consists of multiple runs of the GFS ensemble...in theory that would give it more accuracy than just taking a single GFS ensemble run.  I also like the 500mb ensemble blend maps that CPC puts out at 3PM, where they factor in multiple ensemble products, CMC, GFS, Euro, maybe NAEFS