*Roidzilla 2017* - Final Call Snow Map / Observations

Good Afternoon -

A powerful Roidzilla is set to bring blizzard conditions to our region. Snow is expected to begin between 10pm-12am tonight and taper off between 2-3pm (NYC Metro) and 4-6pm elsewhere. If you wish to learn more about this system, please visit my blog where I did a write-up a couple of days ago.

http://njstrongweather.blogspot.com/2017/03/possible-roidzilla-brewing.html

I feel fairly confident the low pressure center will take a track just off the Jersey coastline. As a result, snow will change to sleet/rain for portions of the coast, NYC, and Long Island but by the time temperatures warm up there may not be precipitation left to fall. Reasons being the 700mb low is forecasted to track over our area which suggests the dry slot from the low level center may track over this area. Fortunately, the 850mb low is expected to remain off the coast so temperatures will not warm too drastically. The coastline will receive a heavy thump of snow and should not take this storm lightly when factoring in the 60-70mph wind gusts that are possible. The jackpot will end up N&W of NYC. Those in the red shaded areas could see in excess of 30 inches of snow. The 700mb frontogenesis is off the charts, the surface low is tracking along the coast so the best banding will be over you, and cold temps and lighter winds could raise your ratios to 13:1 at some point.



Here is my final call snow map. I hope everyone stays safe and enjoys the storm. I will be posting periodically throughout the night. At this point, I am no longer watching models (besides the short range such as RAP/HRRR/WRF) and trusting the consensus track. I am mindful of the fact a track slightly east of guidance would push my snow amounts S&E. You should be mindful of that too. Sometimes large storm systems like these have a mind of their own. And it may not take much. Nowcasting this beast will be a GREAT time!

Get the vino and nutella. It's going to be a long night!

Thank you! Awesome​ work as usual much appreciated

Good work Frank. Now its time for nowcasting.

Well done and thank you Frank.

Just looking at the radar the storm seems to be starting to take shape off the Carolina coast. There is an area of rain and snow in Maryland running out ahead of the main system which could be here by 10 p.m. if it holds together.

HRRR is very cold

Frank any comment on why the NWs official forecast puts the low JUST west of the BM after it goes east of VA Beach and 100 miles east of Atlantic City. Curious. I trust YOU I've just never seen a case where your totals are lower than the NWS

Thanks
James

Frank--

Obviously love the map as I find myself happily tucked into the center of that red zone here in the hills of Hopatcong, NJ, I just want to thank you for the thrilling ride that has been the past week. You really have kept this place buzzing and have been very helpful answering all the questions from amateur snow weenies like myself.

Cheers! (New Belgium DayBlazer for me-- good beer!)

Everyone enjoy the storm.

syosnow94 wrote:Frank any comment on why the NWs official forecast puts the low JUST west of the BM after it goes east of VA Beach and 100 miles east of Atlantic City.  Curious.  I trust YOU I've just never seen a case where your totals are lower than the NWS

Thanks
James

Since there is a 500mb closed vort to our west, it's acting as a pivot and tracking the surface low due north instead of northeast like most of our coastals. Also, the 250mb jet streak is placed in such a way to promote more northerly movement. But again, this is not set in stone yet. Any variations in track more northeast could mean a huge difference in snow totals, especially for eastern NJ/NYC.

DAYBLAZER wrote:Frank--

Obviously love the map as I find myself happily tucked into the center of that red zone here in the hills of Hopatcong, NJ, I just want to thank you for the thrilling ride that has been the past week. You really have kept this place buzzing and have been very helpful answering all the questions from amateur snow weenies like myself.

Cheers! (New Belgium DayBlazer for me-- good beer!)

Everyone enjoy the storm.

Thank you. I work in Hackettstown, not far from you. Enjoy the storm.

RJB8525 wrote:Thank you! Awesome​ work as usual much appreciated

billg315 wrote:Good work Frank. Now its time for nowcasting.

nujerzeedevil wrote:Well done and thank you Frank.

No problem!

aiannone wrote:HRRR is very cold

It already has a foot of snow in eastern PA by 9am. I have a feeling this will be a quick mover. We'll see

Frank_Wx wrote:

syosnow94 wrote:Frank any comment on why the NWs official forecast puts the low JUST west of the BM after it goes east of VA Beach and 100 miles east of Atlantic City.  Curious.  I trust YOU I've just never seen a case where your totals are lower than the NWS

Thanks
James

Since there is a 500mb closed vort to our west, it's acting as a pivot and tracking the surface low due north instead of northeast like most of our coastals. Also, the 250mb jet streak is placed in such a way to promote more northerly movement. But again, this is not set in stone yet. Any variations in track more northeast could mean a huge difference in snow totals, especially for eastern NJ/NYC.

I totally get that. If we do, I'm sure they do which is why I'm confused about their track. They have it moving due north offshore of Virginia and well offshore of Atlantic City then hooking back towards Cape Cod from the BM. 150 miles different than what we are discussing. Crazy no??

Cold HRRR

I went shopping and got beer, wine, milk, cookies, Ben and Jerry's American Dream and ingredients for a rum and coke. Im ready. Binghamton better close tmw!

And now we drink.......

Great map and reasoning Frank. Been noticing meso models been bringing that H7 low further inland, but do keep the 850mb low just offshore. The one way some can be saved from mixing with sleet IF it occurs, is if the mesoscale banding sets up over the area, which would dynamically and rapidly cool the column. I'm watching these dew points right now and man i tell ya, it literally reflects the late January standards. Impressive!

Dunnzoo wrote:

aiannone wrote:I went shopping and got beer, wine, milk, cookies, Ben and Jerry's American Dream and ingredients for a rum and coke. Im ready. Binghamton better close tmw!

My daughter went and got cookie dough to make cookies! Me, beer and Irish Mist acquired Thursday night to beat the rush! Going to be fun trying to verify snowfall rates, no sleep for me!

Great job everyone! Let's just relax and see what unfolds for everyone. I have not looked at the models all day, at this point it is what it is. (Yeah, easy for me to say since I am in a pretty good spot this time!) but no sense making yourself crazy over ticks in model runs. Enjoy whatever mother nature brings you tomorrow!

Sounds good too! I will be up much of the night as well! Expecting 10-20" here in BGM

This??

Frank I'm happy with ur map but why the little sliver of southern westchester out of the red thats all of one maybe two very small towns over from me and the line is on a diagonal. Also are we expect thundersnow? U have not discussed that. The wind will b bad and I'm expect power outages for southern westchester is that included in ur 60 to 70 mph wind area? Thanks so much for all this grabbing some beer as well and gonna try stay up.lol.

So this is the part where we drink and watch the short range models//our windows?

Frank Great map, but what is the right hand column next to your predictions

That gradient near the coast is gonna be fun (or torture) to watch.
Like Lee was saying it could potentially go from 9 to 20" within NYC limits.

jmanley32 wrote:Frank I'm happy with ur map but why the little sliver of southern westchester out of the red thats all of one maybe two very small towns over from me and the line is on a diagonal. Also are we expect thundersnow? U have not discussed that. The wind will b bad and I'm expect power outages for southern westchester is that included in ur 60 to 70 mph wind area? Thanks so much for all this grabbing some beer as well and gonna try stay up.lol.

On second look I probably would include all of Westchester and northern half of Bronx in the red. It's hard to look at every county with these snow maps.