Jump to content
  • Member Statistics

    17,614
    Total Members
    7,904
    Most Online
    Vesuvius
    Newest Member
    Vesuvius
    Joined

December 16-17, 2020 Winter Storm Obs/Nowcasting


WxUSAF
 Share

Recommended Posts

1 minute ago, DDweatherman said:

I think most importantly it was an improvement from both 12k/3k at 12z. Can it muster up further support is the question. We want to see h7/h85 closing off and tightening the thermal gradient. Then if the low was to go a bit east on these gametime runs, we'd be in a pretty good spot. 

ive been hugging the GFS/Euro anyways. But it is a little relieving to see the NAM back off its super warm temps, at least up here

Link to comment
Share on other sites

1 minute ago, mappy said:

ive been hugging the GFS/Euro anyways. But it is a little relieving to see the NAM back off its super warm temps, at least up here

Agreed. ~1.3" QPF to be exact on the 12k for you if you we're wondering. Around 1.5" on the 3k. It would be nice to see the 18z GFS continue what the 12z did but not bring the low over Baltimore. 

Link to comment
Share on other sites

Just now, DDweatherman said:

Agreed. ~1.3" QPF to be exact on the 12k for you if you we're wondering. Around 1.5" on the 3k. It would be nice to see the 18z GFS continue what the 12z did but not bring the low over Baltimore. 

its so weird that the nam is showing such a prolonged sleet fest IMBY when all the temps are below freezing. Am I missing something?

Link to comment
Share on other sites

Just now, mappy said:

its so weird that the nam is showing such a prolonged sleet fest IMBY when all the temps are below freezing. Am I missing something?

Warm nose aloft...upper low not cutoff fully, flow aloft coming right off the Atlantic waters. Surface is cold, above the deck is above freezing. 

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

1 minute ago, ers-wxman1 said:

Warm nose aloft...upper low not cutoff fully, flow aloft coming right off the Atlantic waters. Surface is cold, above the deck is above freezing. 

One forecasting less I've learned from this event: if the NAM shows prolonged SE winds, trust where it's putting the mix line and under-forecast your snow amounts. It's always easier to revise upwards.

  • Like 1
Link to comment
Share on other sites

2 minutes ago, ers-wxman1 said:

Sure

Sure isn't an answer...  I was asking a question. I looked at 850, 925 and surface temps and I only lose 850s for a few hours in the afternoon. Otherwise, the rest of the temps are below freezing. But I did not look at 700 or 500, hence me asking you.

Link to comment
Share on other sites

2 minutes ago, DDweatherman said:

For us, 700mb temps never break above 0. There is a slight pocket between 750-800 that could present issues, but that was more prevalent in soundings around DC than our neck. 

mmm maybe thats whats causing the prolonged sleet depicted on sim radar. 

Link to comment
Share on other sites

1 minute ago, mappy said:

Sure isn't an answer...  I was asking a question. I looked at 850, 925 and surface temps and I only lose 850s for a few hours in the afternoon. Otherwise, the rest of the temps are below freezing. 

This is where you get the sleety frames for a few hours, hr 29 on 3k (750 looks around +2) 

nam3km_2020121518_fh31_sounding_39.66N_76.74W.png

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...