Winter's Finale: March 20th-21st Snowstorm

NWS has Orange County for 10-16 inches but I'm not buying it 100% yet.

The 6Z NAM has me concerned as do other runs that seem to hit a brick wall with the precip at certain points north and west. Nowcast as usual.

RGEM

Scullybutcher wrote:This is what Upton has for me.

* WHAT...HEAVY MIXED WINTER PRECIPITATION TRANSITIONING TO HEAVY
SNOW IS EXPECTED. TOTAL SNOW ACCUMULATIONS OF 7 TO 10 INCHES,
WITH LOCALIZED AMOUNTS UP TO 13 INCHES, AND LIGHT ICE
ACCUMULATIONS ARE EXPECTED.

The weather channel has me for 13 - 20”

Nice, Scully! NWS had my area at 12-16 with light ice accumulation possible.

Bill Evans has my area at 6-10 with possible 12 locally. I'm going with the NWS.

Cp that brick wall is exactly what I see too and has me concerned. We are way to close to the edge when theY show that sharp of a cutoff.

CP and blackwrx.....Please don't rain on my parade! Snowing on it is permissible.

2004blackwrx wrote:Cp that brick wall is exactly what I see too and has me concerned. We are way to close to the edge when theY show that sharp of a cutoff.

Exactly.

I said last night someone in between an area from central Rockland to northern Dutchess will be on a sharp cutoff zone and the 6Z NAM certainly showed that. I'm hoping it's wrong but even the RGEM that skins posted shows it to a degree. This one may not be our storm despite the NWS WSW for 10-16 inches. Like I said I'm still not buying it for here.

Taffy wrote:CP and blackwrx.....Please don't rain on my parade! Snowing on it is permissible.

You'll do great down there Taffy. This is a N&W concern.

Hopefully its just on these runs. I didnt see the cutoff on previous runs. I saw misses south but not the cutoff. So frustrating knowing that miles away is getting hammered and you are getting a dusting. Also daytime light snow prob would really be no accumation in late March.

The 6Z GFS has the heavy stuff after 4 past midnight. That would be a plus for accumulating. It also has a sharp cutoff to the north but not as extreme as the 6Z NAM. Anyone north of the TZ bridge should be concerned IMO.

Im 3 for 3 this month. No problem watching others cash in if it happens that way. Now cast.

Okay I now have a wsw for 12 to 16 awesome but what happened 06z runs are way east!! Should I be concerned that's a big jump. 3km did not even make sense very little precip of any type in NYC area. I hope they were a blip. Euro was east too.

In the past 24 hours the Shore has gone from out of the bullseye to into the bullseye, back to out of the bullseye, and now back into the bullseye. And there is another 24 to go! Round and round she goes...

I'm hoping that if I promise my wife I'll do the taxes, she'll let me take the day off to sit in front of my computer all day. We'll see what she says... ha ha!

jmanley32 wrote:Okay I now have a wsw for 12 to 16 awesome but what happened 06z runs are way east!! Should I be concerned that's a big jump. 3km did not even make sense very little precip of any type in NYC area. I hope they were a blip. Euro was east too.

If you look at my last posts last night before I went to bed I said we’d see this shift of the heaviest band east overnight. As I said when this thing deepens it will wrap up tighter pullling the heavier snow closer to the center and cutting things off further north and west.That’s why my map looks like it does. As of this morning I still like my map.

Bill Evans showing 3-6 for LI NYC. Huh? Arent we under WSW

Yea cp not thinking after seeing some overnight runs this will be a big deal for us. But as you know things could change and will .  You are right we did well with the last storms so happy if our friends to the south cash in

If you look the 6z GFS still has a more expansive precip shield well N&W and provides heavy snow for all of our area (less sleet to the east too). I think a blend of 6z NAM and GFS is close to real solution. NAM is right in wrapping the storm up tight with sharp cutoffs, but probably a bit too far east with cutoffs.

billg315 wrote:

jmanley32 wrote:Okay I now have a wsw for 12 to 16 awesome but what happened 06z runs are way east!! Should I be concerned that's a big jump. 3km did not even make sense very little precip of any type in NYC area. I hope they were a blip. Euro was east too.

If you look at my last posts last night before I went to bed I said we’d see this shift of the heaviest band east overnight. As I said when this thing deepens it will wrap up tighter pullling the heavier snow closer to the center and cutting things off further north and west.That’s why my map looks like it does. As of this morning I still like my map.

I agree with your thoughts. Last nights NAM was too far west with the axis of heaviest snowfall and I thought it would end up east. However the 6z NAM is way east. I think thats just an over correction on the Nams part and it will come back west at 12z more in line with your snow map.

CPcantmeasuresnow wrote:The 6Z GFS has the heavy stuff after 4 past midnight. That would be a plus for accumulating. It also has a sharp cutoff to the north but not as extreme as the  6Z NAM. Anyone north of the TZ bridge should be concerned IMO.

Im 3 for 3 this month.  No problem watching others cash in if it happens that way. Now cast.

I think Westchester and Rockland will do fine. It's further north and west that could be in trouble. There is a sharp cutoff and the 06z nam and rgem don't do me any favors. Even the Euro gives me about .30 of LE. I wouldn't be a bit surprised with much less than the 5-9 NWS is forecasting for me.

6z GFS Wed. Evening:

Yes but 3km nam had like 6 inches for coast not 12 to 16 which is in line with ur map bill. Do u think this will correct west to match ur map again?

billg315 wrote:6z GFS Wed. Evening:

That is a positive this morning like I was saying earlier. The 6Z GFS is showing most of the snow from 4PM to midnight. Sun angle will not be a factor in accumulations at those times. It will be a couple of degrees colder than the last storms too and that should also help the areas accumulate that were screwed in those storms.

jmanley32 wrote:Yes but 3km nam had like 6 inches for coast not 12 to 16 which is in line with ur map bill. Do u think this will correct west to match ur map again?

I do. I think NAM will shift a bit west again today more in line with the GFS I just posted. I think it over corrected last night on shifting the heavy precip east, (maybe even chasing convection?) from it being too far west with the heavy bands last night.

Remember the 0z NAM had a blizzard over NW NJ and NEPA, now in a run 6 hours later it has them in flurries?? I think that is just too much of a shift to be believed when the GFS essentially held to its location.

This Mt Holly 6 am Update for Ocean County is going to make it hard for me to adult today. They just don't talk like this around here:

Wednesday...Strong signal for TROWAL of the now merged coastal
low to be over our region. There is a very distinct Theata E
ridge at 700 and 600 mb on the northwest side of the low in
nearly all of the operational models. Exactly where in our
region is uncertain, it could be over the I95 corridor or
further east over the Coastal Plains. This, along with the
placement of a band of frontogenesis is critical to determining
where the highest threat for mesoscale banding will be during
the day.

Hazards on Wednesday:
Heavy wet snow especially under mesoscale banding. There is the
potential for a 6 to 12 hour period of very heavy snow with snow
rates of 2 to 3 inches at times. We expect to get a majority of
the overall snow accumulation in this period.

NWS Albany discussion: This is mainly for Dutchess/Ulster northward.


Despite what any model says from run-to-run, we have confidence
that there will be a sharp north-to-south gradient of snowfall
with this storm across our area, with much of our area going
from seeing little to no snowfall to seeing close to warning
level snowfall over a short distance (possibly within a distance
of 30 to 40 miles). Based off collaboration with neighboring
offices, WPC and ensemble output, have decided this will be
somewhere across the mid-Hudson Valley northeast into southern
New England. Have included Dutchess and Litchfield Counties in a
Winter Storm Warning for 6 to 12 inches of snow, with locally
higher totals across far southeastern areas. Will continue
Ulster County in a Watch, as well as southern Berkshires, in
case the storm track shifts further north/west, otherwise there
will be a narrow area that see Advisory level snowfall. At this
point, don`t expect Advisory or Warning level snowfall to reach
into the Capital Region (despite what random SREF members or
odd-runs of the NAM may show), as the best frontogenesis looks
to be focused closer to the coastal areas, which makes sense, as
the stacked storm system will generally be sliding more
eastward, as opposed to northeast, and the best lift looks to
just too far away to have an impact this far north.

I should caution again, I do buy the NAM’s idea of a tighter precip shield (which isn’t great for those further N&W) but I think the 0z was too far East with the low center. I also think NAM is picking up better on sleet near the coast.

billg315 wrote:I should caution again, I do buy the NAM’s idea of a tighter precip shield (which isn’t great for those further N&W) but I think the 0z was too far East with the low center.

Do you still think the storm gets close enough to cause mixing issues for coasts?

Upton really bullish with totals wind and thundersnow. Why are they so confident? For a very conservative group of forecasters I’m surprised. Do they not care about the negative trends this morning?