Jump to content
  • Member Statistics

    17,608
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

December 16 2020 CTP Snowstorm Disco and Obs


pasnownut
 Share

Recommended Posts

47 minutes ago, pasnownut said:

Thanks bud. Wasn’t sure. I’d take .8” sleet with a couple inches on top.
You think you’ll get to 18”?  From mesos I think you’ll be right close. 

Next couple hours are crucial but my chances for getting that high are slipping away the longer that band stays arced to my NW and north. It seems to be setting up over 2001kx over to just NW of IPT. @2001kx has to be getting crushed. This is the band that's going to see the excessive totals and it's setting more NW than any guidance had it earlier today. 

Up to 8" with moderate rates. Snowing decent but I probably lost my outside chance at 20". 

  • Like 1
Link to comment
Share on other sites

This is impressive.

Quote

000
NWUS51 KPBZ 170222
LSRPBZ

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PITTSBURGH PA
922 PM EST WED DEC 16 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0921 PM     SNOW             BLACK LICK              40.47N  79.19W
12/16/2020  M13.5 INCH       INDIANA            PA   TRAINED SPOTTER

            13.5 IN AS OF 845 PM, 8 INCHES IN 3 HOURS.


&&

EVENT NUMBER PBZ2002008

$$

JKL

 

Link to comment
Share on other sites

1 minute ago, MAG5035 said:

Next couple hours are crucial but my chances for getting that high are slipping away the longer that band stays arced to my NW and north. It seems to be setting up over 2001kx over to just NW of IPT. @2001kx has to be getting crushed. This is the band that's going to see the excessive totals and it's setting more NW than any guidance had it earlier today. 

Up to 8" with moderate rates. Snowing decent but I probably lost my outside chance at 20". 

You putting much weight into 0z NAMs?. They look decent for part 2. I’m always Leary of wraparound down here but it’s been modeled for multiple cycles even down here. I’m spitballing 2” addl before it pulls NE of us. 

Link to comment
Share on other sites

10 minutes ago, psuhoffman said:

@mappy @losetoa6 @Eskimo Joe @HighStakes @showmethesnow @DDweatherman 

I have been super busy all day...today was a big due day for tons of paperwork and reports before the holiday break.  So forgive me if this was discussed, I haven't been able to keep up.  But wanted to highlight the chances for our area tonight to get a little surprise.  I am going to use the 18z euro because it has been the most consistent on the train...shown it for 5 runs straight now and it gets more pronounced every run.  For the record the NAM's don't really like this idea...the HRRR is hit or miss run to run, but the RGEM 10K and 3K both are in the euro camp.  

We can see that area of precip breaking out to our SW in response to the mid and upper level energy approaching from the ohio valley...

image1.thumb.png.fc3fe5be878d3daa38cd23d5105b8e18.png

 

image2.thumb.png.5d66a9a1d1e1ad9455034d1a4e9b5f9c.png

 

image2.1.thumb.png.566ee0f3d42506e7a66259a228ab2ddf.png

But as of now that energy is not phased up with the coastal and the developing precip is mostly mid and upper level instability related without any connection to the deep moisture transport associated with the coastal system.

However...by 6z we can see the mid and upper levels have caught up and are phasing in with the coastal system and the results to the banding of precip (if that does indeed happen in sync like that) over our area.

image3.thumb.png.6942331cb8a6390a4ace695291023191.png

image4.thumb.png.907869018cffb70288a144ac61051483.png

image5.thumb.png.942447a76c729dcde66b8ba9c1d9b80d.png

As the mid and upper level energy catches up to the surface system and phases that mid and upper level energy and instability will now have access to deeper moisture transport from the coastal.  So we see the banding associated with it really explode.  Keep in mind this is a 1 hour precip plot so that is heavy precip across all of central and northeastern MD.  The red line denotes where I believe the rain snow line would be at this time.  Looking at soundings across guidance the wam layers left at that time are thin enough that heavy precip would overcome north of that line...but that precip moves out slowly over the next 4 hours and that line sags south a bit.  

This next plot is the precip associated with that band that falls between 3z and 9z.  The purple line is my estimate of where north of there all of this would be snow.  The red line is the southern extent of where the changeover gets before about 80% of the precip is moving out.  Not saying there cannot be any snow TV south of that line...but that is my estimate of where I think it is reasonable to think accumulating snowfall could get with this band.  But keep in mind...if that band were to really get going more then even this prog shows....it could cool the column as the heights crash further south.  Stranger things have happened.  Probably the best example of a banding feature like this maxing out was that xmas day miracle snow we got in 2002.  

image6.thumb.png.712377009cdd3ee43d4ea31f83f3d6f0.png

From the QPF if the euro is correct this could actually be a pretty sizeable amount along the northern tier of MD.  Some places could get 4-6" which is an event in its own right.  Maybe even more if everything maxes out perfectly.  Of course...if the mid and upper level energy fails to sync up perfectly it could all just be a band of light precip that cannot overcome the leftover warm layers near 800mb and nothing comes of it.  

Now...how likely is this.  The Euro has been doubling down every run for over 24 hours.  The short range Canadian twins agree.  The HRRR is kinda in between and the NAM says no thank you...it has the banding but too light to trigger the cooling needed to result in anything significant south of the PA line.  The upper level pass is slightly north of ideal...but not bad.  The mid level pass is really good.  It's a matter of do they sync up right.  Models suck at that.  These things surprise both good and bad all the time.  I am going to be an optimist here and say this does come together and we have a decent shot at some accumulating snow across the northern tier of MD tonight.  

 

 

 

Thanks @Cashtown_CoopI was just about to copy it here for the SE crew in this forum.  Good luck.  

  • Like 2
  • Thanks 1
Link to comment
Share on other sites

5 minutes ago, MAG5035 said:

Next couple hours are crucial but my chances for getting that high are slipping away the longer that band stays arced to my NW and north. It seems to be setting up over 2001kx over to just NW of IPT. @2001kx has to be getting crushed. This is the band that's going to see the excessive totals and it's setting more NW than any guidance had it earlier today. 

Up to 8" with moderate rates. Snowing decent but I probably lost my outside chance at 20". 

Just measured 11 inches. The end of the band is parked over here

Link to comment
Share on other sites

5 minutes ago, MAG5035 said:

Next couple hours are crucial but my chances for getting that high are slipping away the longer that band stays arced to my NW and north. It seems to be setting up over 2001kx over to just NW of IPT. @2001kx has to be getting crushed. This is the band that's going to see the excessive totals and it's setting more NW than any guidance had it earlier today. 

Up to 8" with moderate rates. Snowing decent but I probably lost my outside chance at 20". 

it just keeps getting heavier...up to 13" as of 9:25

 

 

cc.jpg

  • Like 5
Link to comment
Share on other sites

20 minutes ago, 2001kx said:

yep had to get the yard stick..how long do you think this will last here?

 

Probably the next hour at least (edit: I'm talking just about the heavy band, not the rest of the event lol). I'm watching to see what that weak spot in returns does down in Somerset County and if we keep building some banding. Back to heavy snow here but probably not as heavy as there. 

  • Like 1
Link to comment
Share on other sites

5 minutes ago, MAG5035 said:

Probably the next hour at least. I'm watching to see what that weak spot in returns does down in Somerset County and if we keep building some banding. Back to heavy snow here but probably not as heavy as there. 

what would cause the models to look at 1am to 4am in the LSV, Mag? Things seems to be progressive right now as far as radar returns.  

Link to comment
Share on other sites

10 minutes ago, MAG5035 said:

Probably the next hour at least (edit: I'm talking just about the heavy band, not the rest of the event lol). I'm watching to see what that weak spot in returns does down in Somerset County and if we keep building some banding. Back to heavy snow here but probably not as heavy as there. 

Thanks..

IMG_20201216_214707.jpg

IMG_20201216_214543.jpg

IMG_20201216_214650.jpg

  • Like 3
Link to comment
Share on other sites

3 minutes ago, MAG5035 said:

8.6" with heavy snow falling now. Bigger and fluffier flakes with this current burst of heavier. 

think this is where Altoona - State College really starts racking up, I can see the pivot occurring on the radar, should swing east.

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...