WidreMann told us it was gonna snow thread

[DopplerWx]

Is sharper better? More negative tilt sooner?

Yea pretty much, less positive tilt initially.

[burgertime]

18z RAP is weaker with the energy but looks like it goes more neutral to negative sooner than the 17z run of the RAP.

[mackerel_sky]

LOL ! Don't hate on the little bullseye the GFS was showing from CAE - GSP

Only NC exists on this sub-forum.

[JoshM]

I wonder if we'll see any Watches/Advisories with the afternoon NWS updates.

[burgertime]

The WV is making me think we might have a bigger deal as the day goes on. The energy  in the plains looks to be diving in a north to south direction and it is farther west. What this may mean is we might have a bigger storm and it may be delayed for a few hours and slower. I don't have a dog in the fight so it really doesn't effect me, but those to the east of the Triad, Char., Columbia, and eastern Ga. thing just got a lot better for you guys in my opinion.

 

http://www.goes.noaa.gov/GSSLOOPS/ecwv.html

 

Very good catch. It's really about watching in real time now. Let's see if we can get a last minute move slightly west to help more out. 

[sctvman]

WLTX's TrueView model valid at 7pm Saturday night.

 

[SnowNiner]

I am not so sure a Lee trough is entirely a good thing when it comes to BL issues.

 

That's my part two issue with this event; even if we do get a good amount of moisture it comes in mid afternoon with highest temps of the day.  It's rain changing to snow with above freezing surface temps.  Slushy dusting at the end.  What is that a slushting? 

 

Ok I'll shut up now, I'm just really itching for a good snowstorm.  On to the pattern thread I go...

[DopplerWx]

WLTX's TrueView model valid at 7pm Saturday night.

 

WLTX.jpg

what's with the dry slot i wonder?

[beanskip]

Really interesting and, I think, significant trend being shown on the RAP which is dramatically weakening the Texas s/w vs. prior runs.

 

Here is 12z RAP at 16 hours:

 

 

Now, here is the recent 18z RAP at 10 hours:

 

You will also note, if you toggle between the two, what is clearly an earlier move toward a neutral tilt in the more recent RAP run.

[ILMRoss]

I feel like a weaker southern shortwave wouldn't be good for those of us on the coast.

[burgertime]

Really interesting and, I think, significant trend being shown on the RAP which is dramatically weakening the Texas s/w vs. prior runs.

 

Here is 12z RAP at 16 hours:

Rapstrongone.png

 

 

Now, here is the recent 18z RAP at 10 hours:

RAPweakone.png

 

You will also note, if you toggle between the two, what is clearly an earlier move toward a neutral tilt in the more recent RAP run.

 

The northern energy is significantly weaker on the 18z RAP however in the end I think the tilt is enough that is more moisture associated with it than at the end of the 17z run. 

[Pilotwx]

Really interesting and, I think, significant trend being shown on the RAP which is dramatically weakening the Texas s/w vs. prior runs.

 

 

 

You will also note, if you toggle between the two, what is clearly an earlier move toward a neutral tilt in the more recent RAP run.

It might be that they are phasing sooner thus weakening the Texas s/w. 

[msuwx]

I wonder if we'll see any Watches/Advisories with the afternoon NWS updates.

Not from the Raleigh office....not sure about GSP.

 

Edit: No watches at this point....going with a WWA.

[packfan98]

Not from the Raleigh office....

 

Interesting.  I thought there might be some watches for at least areas NE of RDU.

[beanskip]

Matthew -- what is significant (if any) of the RAP trend to weaken the Texas s/w sooner? Let's just assume the RAP is sniffing something out there.

Not from the Raleigh office....

[buckeyefan1]

WLTX's TrueView model valid at 7pm Saturday night.

 

WLTX.jpg

Just last night Jim was saying it probably wouldn't even rain

 

what's with the dry slot i wonder?

This is SOUTH Carolina Nice to see the precip increase, can't wait to get home so I can check out bl issues

[msuwx]

Interesting.  I thought there might be some watches for at least areas NE of RDU.

 

Still a little too much uncertainty to pin down specific products....plus there's still a little time to work with.

 

 

Matthew -- what is significant (if any) of the RAP trend to weaken the Texas s/w sooner? Let's just assume the RAP is sniffing something out there.

As you know, the orientation of the trough is the biggest factor really. It's tough to tell what the RAP is doing....these are fairly subtle areas of vorticity we are looking at. If the TX vort were to just be slightly quicker, the trough goes neg tilt faster and you get a bigger system. If the TX vort is slower, the opposite.

 

If it weakens a ton, you wind up with less phasing, but it might have a different impact on the trough orientation.

 

Very tough to say at this point...

[beanskip]

15 SREF clearly going negative tilt faster -- the impact on QPF, however, is to shift the main axis of heavier precip east. Actually, the area of .25 is expanded a bit west, but the westernmost edge of the .1+ QPF collapses back toward the east. It's funny because the 700 RH field looked a little juicier. Oh well, who knows ....

[Bozart]

From RAH:

 

AS OF 245 PM FRIDAY...    ...A WINTER WEATHER ADVISORY HAS BEEN ISSUED FOR CENTRAL AND EASTERN   PORTION OF NORTH CAROLINA FOR SATURDAY AFTERNOON AND EVENING...  

[Buddy1987]

6 hr 18z nam looks more like 12z 12 hr GFS albeit it still has the southern vort more energized lets see if Nam adjusts any.

[beanskip]

18z NAM running. If having the southern stream s/w move faster is a good thing that the early hours of this run are good news. 12z run at 15 hours had that s/w on Tex./Mex. border. This run at 9 hours it's a good 150-200 miles east.

[burgertime]

Nam looks like it's going to be better than it's 12z run. Looks to go negative a tad quicker. 

[Uncle Nasty]

We are heading to Boone tonight to visit some friends. He told me they weren't really expecting anything from this system. Looks like most of the precip will be far east of Boone. For all of you mets out there does this seem pretty accurate? Looks like Boone will be about 100 miles too far west to catch anything other than token flurries.

[Buddy1987]

12 hr has northern energy stronger diving down into southern KS with southern vort just west of San Antonio if I'm not mistaken

[franklin NCwx]

You wanna see the southern sw get out in front of the northern stream like the nam is doing here.

 

 

 

 

[burgertime]

@18 we're getting a phase. Looks like it has a better tilt to me compared to 12z. 

[Buddy1987]

Lol at the Nam no wonder why you can't trust it at 12z 21 hr it had the southern vort near San Antonio and now at 15 hr 18z it has it entering western LA but yes looks much better with the northern energy swinging in from behind

[burgertime]

Light strip of precip @21 going from eastern GA into SC and into eastern NC.. looks wetter than 12z NAM. 

[beanskip]

It does. But you would think it would be more pronounced given the really major change in the speed of the southern s/w. That's a pretty big trend this early in a run.

@18 we're getting a phase. Looks like it has a better tilt to me compared to 12z. 

[MillerA]

Gsp discussion is out. Can't paste from phone. No watches or advisories issued.