DISCUSSION ONLY: Snow/rain/slopfest potential Tuesday 11/27/2012

[famartin]

Euro is about .1-.25".......

0.20" at PHL. Looks a bit warmer too... probably due to decreased precip intensity.

[phlwx]

I really think the NAM is an outlier and overdoing the qpf. If the Euro were lending even some support I'd be a bit more bullish on this but not having a second major model on your side doesn't help your cause.

[dan88]

6Z NAM- more amplified, .75+ peak WNW of Philly, Southern edge of the region of .5 liquid runs near the Maison Dixon line.

3Z SREF- more amplified then 21Z, mean has a peak of .50 liquid from 37-51 hours West of Philly.

[phlwx]

6z NAM QPF. Cut that in half and it wouldn't be terribly out of whack but even 50% of this seems high.

[famartin]

Yeah, 6Z NAM is mostly snow at TTN. Barely, but it is. And 0.70" of precip to boot (in fact, that's REALLY why its snow at all). Won't buy it til I see something else suggest its right.

[am19psu]

From a meteorological standpoint, it was a monster bust for me personally. It wasn't about what did or did not fall in my backyard, it's the fact I bought into the models so badly, I feel embarrassed in the wake up that storm for what I anticipated across our entire area.

In post-analysis of that event, I don't feel nearly as badly as I did the day after forecasting. It was a really tough event to nail down due to the mesoscale nature of the forecast. The fact that most of us had the right idea about banding and snowfall rates being the keys to accumulating snow were spot on. It's really tough to nail down exactly where that would be and I'm not losing any sleep that I was off on where those bands set up by 100 miles. Yeah, it sucks that I missed the forecast for MBY and I definitely had some egg on my face the next day at work, but what else were you going to forecast for that day?

[Parsley]

In post-analysis of that event, I don't feel nearly as badly as I did the day after forecasting. It was a really tough event to nail down due to the mesoscale nature of the forecast. The fact that most of us had the right idea about banding and snowfall rates being the keys to accumulating snow were spot on. It's really tough to nail down exactly where that would be and I'm not losing any sleep that I was off on where those bands set up by 100 miles. Yeah, it sucks that I missed the forecast for MBY and I definitely had some egg on my face the next day at work, but what else were you going to forecast for that day?

Good points. One thing you highlighted was the likelyhood of 6+ inches of snow in a small band and that did occur. I guess in the end with a 50-75 mile shift in the main banding that caused the result that occured.

As for this event, NAM could be overdone on QPF .....does anyone remember how the Euro did with the early November storm in terms of QPF forecasts?

[chubbs]

Quite a difference between 06 NAM+GFS just north and west of PHL. NAM gives Lancaster + Reading 8" and Trenton 7" with temperatures near 32 so most should accumulate oin grass. GFS is warmer at surface with lighter precip so little would accumulate. Phl+ILG are too warm to accumulate in either model.

[anthonyweather]

Well here goes nothing. I go in for my interview in 15 mins with penndot! For a winter maintenance driver, hoping I can become the go to road condition guy here ! Whew never been so nervous in my life!!!!!

[chubbs]

09 SREF is a littlle wetter. Area >0.5" has expanded along Pa/Md border.

[Parsley]

12Z NAM takes the best UVV's right across Lehigh Valley/SE PA and central Jersey after 12z Tuesday. Looks like areas from Philly south would miss the best lift.

[chubbs]

NAM continues to like areas just N+W from phl.

[Parsley]

NAM continues to like areas just N+W from phl.

Much like the last event you got from a thumping snow to very light rain/snow mix outside of the best upper level support.

Now.......where does that set up? Last time the gradient was on an axis north/south. This time appears an west/east axis.

[Porsche]

Well out here in Lancaster, just hoping to see a coating, am thinking that maybe possible.

[NaoPos]

12Z NAM takes the best UVV's right across Lehigh Valley/SE PA and central Jersey after 12z Tuesday. Looks like areas from Philly south would miss the best lift.

verbatim, its a lehigh valley-sepa-SNJ qpf*** bullseye. havent looked at thermal profiles...

check 1-2..looks like the 925 contour runs dc-NYC...amazing how it runs I-95. whoever built that road was thinking "lets screw these mets" !! haha.

[chubbs]

12 z NAM a little wetter near phl

[Parsley]

Not to jinx it for Voyager, but this is looking good for the Lehigh Valley.

[Heisy]

I'm rooting you guys in the burbs on, but just remember the NAM is too juicy and NW around this time frame a lot. I'd be cautiously optimistic.

[Quakertown needs snow]

timing could cause some travel issues N/W during am rush?

school delays?

[Quakertown needs snow]

Not to jinx it for Voyager, but this is looking good for the Lehigh Valley.

Steve is use to it, no worries

[am19psu]

timing could cause some travel issues N/W during am rush?

school delays?

Not sure it will get here by then. Early dismissal?

[Porsche]

Adam do you think the rates are heavy enough out our way for a coating to an inch maybe?

Thanks

[am19psu]

Adam do you think the rates are heavy enough out our way for a coating to an inch maybe?

Thanks

Yup. But that's about it.

[Porsche]

Yup. But that's about it.

Thanks wasn't expecting any more than that anyway, hey it's still November and since everyone seems to agree this winter will be better than last, I'm happy.

[White_Mtn_Wx]

timing could cause some travel issues N/W during am rush?

school delays?

Be sure to do your home work tonight...now get to posting those radar maps.

[chubbs]

NAM R/S line runs near PA/Md border to near PHL. Quite a gradient just NW of PHL. Areas along turnpike get 6"+. I-95 through SJ/De/Ne MD zip.

[Heisy]

It's going to suck for it to be snowing for 8 hours and not get more than a coating in Philly lol. Though I guess it will be rain when we're not under the heavier echoes.

[tombo82685]

NAM R/S line runs near PA/Md border to near PHL. Quite a gradient just NW of PHL. Areas along turnpike get 6"+. I-95 through SJ/De/Ne MD zip.

yea i looed at the sounding for my work on twister data which is maybe 15 miles from the airport but has 500 ft in elev and its solidly a snow event. What also helped, the heavier echoes came over the region. If those echoes trend further south it would help areas along i95. The nam did cool off a good bit from 6z cause the heavier choes came further south. That will be the wild card on this where that banding sets up like with the early nov storm.

[Parsley]

That will be the wild card on this where that banding sets up like with the early nov storm.

Comparing the 00z, 06z and 12z NAMs, the best UVV's definetely are trending north away from Philly metro (as they slide west to east across our subforum). Like you said, if you can't get under those for a few hours, you'll have a repeat of what we saw in early November across SE PA.

Check out the difference at 15z at 700mb Tuesday, between the 00z NAM and 12z NAM.

[JERSEYSNOWROB]

and once again here in NW Monmouth County we are sitting right on the rain/snow line, yet the colder air always seems to win out here in these situations. As long as the intensity of the precip picks up, we 'may' be ok here for an inch or two.