Jump to content
  • Member Statistics

    17,610
    Total Members
    7,904
    Most Online
    Vesuvius
    Newest Member
    Vesuvius
    Joined

NYC Jan 20/21 Obs and Discussion Thread


am19psu

Recommended Posts

Just a little bit more QPF and we could get to low end warning criteria snows. Right now we're in an advisory for 3-4" but maybe 5-6" isn't out of the question with 6" meeting warning levels.

The meeting criteria part doesn't apply to just a single point within a forecast zone. Six inches would need to be the average across the forecast zone, or at least a significant portion of a forecast zone receiving six inches. If 95% of a forecast zone recieves 4 or 5 inches and one particular town gets 8 inches, it's still a good forecast to not issue the warning. In other words, as it has been explained to me by NWS mets, those localized high amounts don't really count for anything with regard to verification.

Link to comment
Share on other sites

  • Replies 962
  • Created
  • Last Reply

Lots of 1/2 mile visibilities in southern Ohio and the forecast discussion out there mentions a deep layer of lift intersecting a favorable snow growth region. I don't have cross sections in front of me but I think this should translate eastward. Moderate to high probability of 4" I would expect.

Link to comment
Share on other sites

yep... people will be ready.. except for a couple of buddies of mine who I told yesterday that we'd get an inch or two at best.. :P

:lmao: This kind of dilemma only seems to happen to people who are really knowledgeable and plugged in about the weather. I decided a long time ago to profess ignorance when asked by friends or colleagues about a forecast.

Link to comment
Share on other sites

That deform band which shows up on the NAM and the high res models over eastern sections of NJ should be a red flag for everyone to indicate that the GFS is likely underdone on QPF and underestimating dynamics thanks to its lower resolution. Honestly, we have seen plenty of warnings issued with 4-8" totals forecasted and this event fits the bill. I'm finding it harder and harder to rule out a 0.75" total. Give NJ between 0.5 and 0.75, with ratios in the lower teens, and enhancement thanks to eleveation and you could easily approach 12".

Link to comment
Share on other sites

LOL, just like if the radar didn't look that impressive people start calling for a bust 8 hours even before the snow is scheduled to start

nowcasting, under-modeled moisture connection to the gulf, some areas reporting heavier snow than they were supposed to get....yup, classic low end winter storm weenie-isms coming out in full force today.

Link to comment
Share on other sites

So that would indicate that the total QPF output could be understated since that's not being taken into account by the models?

This is doubtful. Models appear reasonable as is. Gulf moisture connection to our region appears minimal. Precipitable water is modest. At issue is the intensity of lift, and to a lesser degree its duration. That's how we get more snow out of this. Strong lift, slightly longer duration, good ratios.

Link to comment
Share on other sites

This is doubtful. Models appear reasonable as is. Gulf moisture connection to our region appears minimal. Precipitable water is modest. At issue is the intensity of lift, and to a lesser degree its duration. That's how we get more snow out of this. Strong lift, slightly longer duration, good ratios.

Thanks for the explanation.

Link to comment
Share on other sites

Is that really true, I have heard of that before but I wasn't sure if if was true or not.

Looks like the true arctic air finally moved in...dewpoints have dropped significantly over the past couple hours. Now in mid to upper teens for most, with temps right around freezing. Should be good temps tonight for the snowfall...

Link to comment
Share on other sites

either or. It has something to due with ice crystals. Its always a good sign IMHO.

Sounds like the euro is still good for the area.

This thing really trended north over the past 36 hours. Originally heaviest precip axis was near Delmarva/S NJ/M-D line, now it looks to be from N NJ/NY State border NE up to Boston....

Link to comment
Share on other sites

"Halo Around the Sun or Moon, Rain or Snow is Coming Soon..."

never fails for me.

either or. It has something to due with ice crystals. Its always a good sign IMHO.

Sounds like the euro is still good for the area.

Yup. I always look for it around the sun if it is a nighttime/overnight storm the late afternoon before the snow is forecasted and it never ever fails. On top of that it has become part of the enjoyment of a snowstorm for me.

Link to comment
Share on other sites

:lmao: This kind of dilemma only seems to happen to people who are really knowledgeable and plugged in about the weather. I decided a long time ago to profess ignorance when asked by friends or colleagues about a forecast.

Yea...nobody even knows I follow a weather board haha...except my girlfriend who recently found out and thinks it is...interesting...

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...