Jump to content
  • Member Statistics

    17,722
    Total Members
    7,904
    Most Online
    BlazerTAGDE
    Newest Member
    BlazerTAGDE
    Joined

Discussion-OBS Weekend Feb 8-9 Another mainly 12 hour snow-ice event possibly changing to rain before ending Sunday. NYC-LI-S of I78 on the edge?


wdrag
 Share

Recommended Posts

15 minutes ago, RU848789 said:

0Z NAM and ICON, fwiw...still think the NAM map with the "hole" in CNJ is improbable (I get a bigger early thump SW of CNJ and more N of CNJ with the later coastal, but not sure I've ever seen this before).  

Also, kind of curious if folks in this forum like seeing the zoomed in Pivotal maps or the regional mid-Atlantic or NEUS maps.  

sn10_acc-imp.us_state_ne_s.png

sn10_acc-imp.us_state_ne_s.png

Whichever map shows me getting the most snow works for me

  • Like 2
  • Weenie 1
  • 100% 1
Link to comment
Share on other sites

35 minutes ago, MJO812 said:

Cmc is nice

snku_acc-imp.us_ne.png

I think something is wrong with the Kuchera calculation for that CMC map.  The algorithm is liquid equivalent ratio (RAT) is 12.0 + 2.0*(271.16-MaxT) and looking at Philly, for example, the 10:1 ratio is 4.0", whereas the Kuchera for Philly is essentially 0.0, which makes no physical sense at all, especially given the algorithm.  For the SLR to be 0 means that the max column temp in the column would have to be 277.16K (6C or 42.8F), so the equation would be SLR = 12.0 + 2.0(271.16-277.16) = 0.  It just makes no sense.  It's another reason I almost always use 10:1 ratio maps, so I know how much QPF is falling as 10:1 snow and then one can still adjust.  

https://www.facebook.com/hopwrf/posts/562550350492139

sn10_acc-imp.us_ma.png

Link to comment
Share on other sites

2 hours ago, RU848789 said:

0Z NAM and ICON, fwiw...still think the NAM map with the "hole" in CNJ is improbable (I get a bigger early thump SW of CNJ and more N of CNJ with the later coastal, but not sure I've ever seen this before).  

Also, kind of curious if folks in this forum like seeing the zoomed in Pivotal maps or the regional mid-Atlantic or NEUS maps.  

sn10_acc-imp.us_state_ne_s.png

sn10_acc-imp.us_state_ne_s.png

I cant stand the Mid Atlantic maps, what's happening in Delaware, Maryland and Cape May is of no interest. There's 2 other forums for those regions.

Link to comment
Share on other sites

9 minutes ago, HeadInTheClouds said:

That's 10:1. It should be higher than that N and W. 

SWFE usually have low snow ratios because the warming air aloft often makes the snow making/max lift region in the cloud above the ideal temp for dendrites which form at -12 to -18C. So ratios are more like 10-1 or even less in some cases. Snow ratios are mostly determined by the cloud conditions where the snow forms. If the max lift is in the -12 to -18C region, ratios are maximized. 

  • Like 4
  • Thanks 1
  • 100% 1
Link to comment
Share on other sites

59 minutes ago, jm1220 said:

SWFE usually have low snow ratios because the warming air aloft often makes the snow making/max lift region in the cloud above the ideal temp for dendrites which form at -12 to -18C. So ratios are more like 10-1 or even less in some cases. Snow ratios are mostly determined by the cloud conditions where the snow forms. If the max lift is in the -12 to -18C region, ratios are maximized. 

NWS Albany is expecting higher ratios north of 84 where I am. This makes sense with possibility of DGZ being tapped and lows in mid 20's. Most models give this area .6 or so QPF and NWS has Poughkeepsie area expected snowfall around 8 inches. 

Link to comment
Share on other sites

NWS will likely go with a WWA for NYC metro for 3-5" locally 6" later unless models trend upwards with amounts.

Also 6z RGEM hinting at 2 areas of banding, one just north of NYC and one in central NJ with a subsidence zone in between. Gotta watch that. If that comes to fruition I could see the southern band being a bit more north. 

 

  • Like 1
Link to comment
Share on other sites

14 minutes ago, SRRTA22 said:

NWS will likely go with a WWA for NYC metro for 3-5" locally 6" later unless models trend upwards with amounts.

Also 6z RGEM hinting at 2 areas of banding, one just north of NYC and one in central NJ with a subsidence zone in between. Gotta watch that. If that comes to fruition I could see the southern band being a bit more north. 

 

The subsidence zone will always be the border of Middlesex and Union counties, right around Colonia/Rahway. Book it. Seen it so many times people think I'm lying; have had 3 inches when New Brunswick had a foot...

Link to comment
Share on other sites

14 minutes ago, SRRTA22 said:

NWS will likely go with a WWA for NYC metro for 3-5" locally 6" later unless models trend upwards with amounts.

Also 6z RGEM hinting at 2 areas of banding, one just north of NYC and one in central NJ with a subsidence zone in between. Gotta watch that. If that comes to fruition I could see the southern band being a bit more north. 

 

It’s the same rule as before, if snow comes in like a wall there’s a shot at the higher end accums. If shredded up the warm air will have an easier time advancing and changeover is sooner. 

  • Like 4
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...