Jump to content
  • Member Statistics

    17,607
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

Winter 2013-14 Pattern Discussion


CAD_Wedge_NC

Recommended Posts

I can't think of a time in the past 5 years that the models have locked on to such a solution for major CAD and zr. This has the best potential for a major ice storm that we have seen in well over 5 years. I'll be firing up the generator and making sure my gas cans are full in the next couple of days.

TW

Link to comment
Share on other sites

  • Replies 2.6k
  • Created
  • Last Reply

I can't think of a time in the past 5 years that the models have locked on to such a solution for major CAD and zr. This has the best potential for a major ice storm that we have seen in well over 5 years. I'll be firing up the generator and making sure my gas cans are full in the next couple of days.

TW

You guys definitely have to keep an eye on this.  If anything is showing up even just a bit for as far South as the Midlands.. there is a real threat that could likely materialize up in your area.

Link to comment
Share on other sites

Looks like TN and VA are the big winners re: precip amounts for the first CAD event on the 18z GFS.

We don't get CAD on this side of the mountain. I have had a little more time to look at things and the GFS ensembles from 12z look a lot like the Euro, meaning wintry stuff further north and west, except CAD areas east of here. I am just speaking for late next weekend. warm 850s into east TN. But is the idea right??? Who knows? lol

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

This event looks different from the last "event". We had prolong dry/cold air for days to cool the surface with extremely low dps. This helped the Triad see a little glazing. 

 

accum.freezing.20131126.gif

 

 

Now it looks wet and going over to freezing rain after the surface is exposed to 60-70 degree weather...several days of it. In fact, most on the board do not see below freezing temps after tonight until the event actually occurs. Raleigh doesn't see freezing temps period until the event.

 

Not a whole lot to discuss. CAD strength to fluctuate for several days on the euro/gfs. May not know the true extent until the NAM gets into range. Likewise, I expect most of us to be on the fringe of Rain/Freezing Rain. 

Link to comment
Share on other sites

We don't get CAD on this side of the mountain. I have had a little more time to look at things and the GFS ensembles from 12z look a lot like the Euro, meaning wintry stuff further north and west, except CAD areas east of here. I am just speaking for late next weekend. warm 850s into east TN. But is the idea right??? Who knows? lol

Sent from my iPhone using Tapatalk

Right...I was just labeling the event The Cad Event, since there were multiple precip events on the GFS. What I meant to say was that parts of TN up through VA looked like the best precip amounts for the event. I didn't say it very well, though.

Link to comment
Share on other sites

We don't get CAD on this side of the mountain. I have had a little more time to look at things and the GFS ensembles from 12z look a lot like the Euro, meaning wintry stuff further north and west, except CAD areas east of here. I am just speaking for late next weekend. warm 850s into east TN. But is the idea right??? Who knows? lol

Sent from my iPhone using Tapatalk

Right...I was just labeling the event The Cad Event, since there were multiple precip events on the GFS. What I meant to say was that parts of TN up through VA looked like the best precip amounts for the event. I didn't say it very well, though.

I figured it was something like that. lol..... Precip amounts on the GFS at hour 180, for the previous 72 hours show a 4 inch qpf bullseye in TN. Pretty crazy amounts being shown. It's pretty wet for a good part off NC too. I hope the cold press is sufficient to get more of the board than currently shown. I really think the CAD being shown is the first "real deal" in quite some time for you guys....... Old school if you will.

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

We don't get CAD on this side of the mountain. I have had a little more time to look at things and the GFS ensembles from 12z look a lot like the Euro, meaning wintry stuff further north and west, except CAD areas east of here. I am just speaking for late next weekend. warm 850s into east TN. But is the idea right??? Who knows? lol

Sent from my iPhone using Tapatalk

 You are correct. You don't have cold air damming on that side of the Apps. However, you can still get low-level cold air bleeding down in over-running events, if the correct pattern sets up. Will it happen this time? Too early to tell.

Link to comment
Share on other sites

Right...I was just labeling the event The Cad Event, since there were multiple precip events on the GFS. What I meant to say was that parts of TN up through VA looked like the best precip amounts for the event. I didn't say it very well, though.

I am w/ tnwxnut...CAD is not an E TN deal. We do get ice events once in a blue moon. Here, the cold air has to be trapped in the valley first and then overrunning occurs. It almost never bleeds in...I doubt this event goes ice on the first wave for E TN. Maybe the second potential event. However, if the arctic boundary pushes further south than modeled(as some mets have guessed it might) it could happen. A lot is still on the table in terms of sensible weather.

Link to comment
Share on other sites

You are correct. You don't have cold air damming on that side of the Apps. However, you can still get low-level cold air bleeding down in over-running events, if the correct pattern sets up. Will it happen this time? Too early to tell.

We usually get warm air bleeding UP to be fair. lol

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

Morristown is warning of bad flooding this weekend as a possibility. I do think E TN gets nailed with heavy rain. I noticed TVA pumping a ton of water this past weekend. They have top notch hydrologists and mets...when you see them clearing water it is best to take note.

 

I agree. I also see neighboring NWS Blacksburg usually do the best with winter weather east of the mountains. I often look to them over GSP. Below is from Blacksburg.

 

The European model (ecmwf)/GFS are all over the place with regards to the strength and the placement of a potential Arctic high

pressure late weekend. This has huge implications on if or how much precipitation will be thrown back into a cold wedged airmass over

our region...which could lead to rain...snow...ice...or all three Sunday night into Monday. Still many days to watch the pattern evolution over the next week and much too early for any specifics.

Link to comment
Share on other sites

RAH not saying much about precip types but does acknowledge the CAD next weekend:

 

FRI NIGHT THROUGH SUN: FORECAST CONFIDENCE IS HIGH THAT A STRONG
COLD FRONT WILL PROGRESS THROUGH CENTRAL NC SOMETIME FRIDAY NIGHT
AND SATURDAY...THOUGH THE PRECISE TIMING IS DIFFICULT TO ASCERTAIN
THIS FAR OUT IN THE FCST. EXPECT ANAFRONTAL PRECIP ALONG AND BEHIND
THE COLD FRONT...WITH OVERCAST SKIES/RAIN AND FALLING TEMPS FOR MANY
HOURS IN THE WAKE OF THE FRONT...MOST LIKELY DURING THE DAY
SATURDAY. TEMPS WILL HIGHLY DEPEND ON THE TIMING OF THE FRONT...AND
AT THIS TIME EXPECT LOWS RANGING FROM THE MID/UPPER 40S FAR NW TO
NEAR 60F FAR SE FRI NIGHT...WITH HIGHS SAT VERY NEAR LOWS SAT
MORNING IN MANY LOCATIONS AS COLD ADVECTION AND EVAP COOLING ASSOC/W
ANAFRONTAL PRECIP RESULT IN FALLING TEMPS DURING THE DAY/AFTERNOON.
ANAFRONTAL PRECIP WILL LARGELY END BY SAT EVENING...THOUGH PRECIP
CHANCES WILL INCREASE ONCE AGAIN DURING THE DAY SUNDAY AS LOW-LEVEL
SOUTHERLY FLOW STRENGTHENS ATOP A PRONOUNCED SFC RIDGE AXIS
EXTENDING SOUTHWARD INTO THE CAROLINAS FROM STRONG HIGH PRESSURE
(1040-1045 MB) CENTERED IN NEW ENGLAND. -VINCENT

Link to comment
Share on other sites

I agree. I also see neighboring NWS Blacksburg usually do the best with winter weather east of the mountains. I often look to them over GSP. Below is from Blacksburg.

The European model (ecmwf)/GFS are all over the place with regards to the strength and the placement of a potential Arctic high

pressure late weekend. This has huge implications on if or how much precipitation will be thrown back into a cold wedged airmass over

our region...which could lead to rain...snow...ice...or all three Sunday night into Monday. Still many days to watch the pattern evolution over the next week and much too early for any specifics.

Applies to almost all people in the upper south. Where that arctic boundary sets up shop is the key. Until we know that...just no way to know precip types. The models look to have 2-3 waves rolling up the boundary. The first one is all rain for TN. The second/third waves are the ones I am watching. We get wintry weather from these types of set-ups...but usually with some cold air already in place and a reinforcing shot comes in. Like I said, lots of options west of the Apps on the table...Blacksburg's disco would work on this side of the Apps as well. If that cold air banks up against the west faces of the Apps, that is when we get ice...but is rare.
Link to comment
Share on other sites

I figured it was something like that. lol..... Precip amounts on the GFS at hour 180, for the previous 72 hours show a 4 inch qpf bullseye in TN. Pretty crazy amounts being shown. It's pretty wet for a good part off NC too. I hope the cold press is sufficient to get more of the board than currently shown. I really think the CAD being shown is the first "real deal" in quite some time for you guys....... Old school if you will.

Sent from my iPhone using Tapatalk

Yep, this definitely has an "old school" feel to it. The first marker for any real non-token winter storm threat for a large part of the area is a strong, favorably located high pressure. This, we appear to have....step 1. :)

Link to comment
Share on other sites

Yep, this definitely has an "old school" feel to it. The first marker for any real non-token winter storm threat for a large part of the area is a strong, favorably located high pressure. This, we appear to have....step 1. :)

 

I agree.. The models have presented a possibility of what might happen and the signal appears to be pretty strong. However, over-running events are hard to nail down inside 48 hours much less a week away..... Even at this range, I believe that an over-running event will occur and we will get some precip. As to how the cold air will get involved is pure speculation at this point but it is a good event for us to track. What's more important is the model accuracy leading up to this event. If we do get a significant winter event out of this pattern, The GFS will have led the way in the LR and should be favored during the remainder of winter with regard to similar cases.

Link to comment
Share on other sites

I don't really understand the mindset of holding off on a thread, to be honest.  What difference does it make?  Most of the discussion in this thread is talking about a specific storm potential, not the overall December pattern discussion, so it would make sense to create a new thread, IMO.  I don't really care too much, though, so whatever is fine.  I guess there's the new thread jinx, but I don't think many of us really believe in that. :D

 

We have a big subforum for a reason.  I remember the era of the superthreads back when this was EasternWx and we didn't have regional subforums, but why not use the subforum as it was intended?

 

That's all I will say before this gets too off-topic, though.

Link to comment
Share on other sites

Yeah good point, but the ensembles didn't really agree if I remember correct.

Sent from my iPhone using Tapatalk

Correct.... the Euro has biases, we all know that, but we can see through the smoke most of the time. Earlier, the Euro was showing an amped up Lakes cutter with this potential. That was its' bias showing and most of us could recognize it. The Euro likes to bomb out and phase storms too easily. This is the one thing everyone has to remember as we head deeper into the cold season. A lot of us were fooled by the Euro earlier this Fall when it showed a wrapped up snowstorm in the medium range. I was hoping that the up-grade had gotten rid of this but once again it proved to be the same old Euro. as I said in an earlier post, I am more concerned with model accuracy that anything. Let's sit back, discuss the event, and watch the trends.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Guest
This topic is now closed to further replies.
  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...