Feb 11-13: Nowcast/Obs

[wxdude64]

29 minutes ago, wxdude64 said:

Snowing at well over an inch an hour here now, right at 2 inches.

No new pic, but 3 inches now, inch in 30 minutes. Mom lives 20 miles south, she has sleet. 

[SomeguyfromTakomaPark]

New 3k NAM spikes us to 36 and starts as rain lol.

Hopefully that's not correct.

[clskinsfan]

NAM looks good to me. DCA sounding at 03Z. And DC already has 5 inches on the ground at this point. 

[stormtracker]

3 minutes ago, SomeguyfromTakomaPark said:

New 3k NAM spikes us to 36 and starts as rain lol.

Hopefully that's not correct.

Are you located somewhere other than Takoma Park rn?

[MN Transplant]

Parent NAM is an inch an hour from 4-10pm.  Always fun to get a NAM’ing.

[NorthArlington101]

Just now, MN Transplant said:

Parent NAM is an inch an hour from 4-10pm.  Always fun to get a NAM’ing.

Was a gorgeous run. Nice time for it.

[clskinsfan]

[LP08]

3k soundings at 2z tonight show some sleet getting awfully close to the city.  Probably rate dependent.

[SomeguyfromTakomaPark]

Just now, stormtracker said:

Are you located somewhere other than Takoma Park rn?

No

Both NAMs look like slightly more QPF for DC.

[aldie 22]

Just now, clskinsfan said:

Yeah that's north a little bit

[NorthArlington101]

3k smacks DC metro right in the face too. North shift from 06z - still running.

[stormtracker]

Yeah, 3k is nice too.  Sleet almost makes it to or could just be over DC for like an hour on the 3k and then cold collapses to the SE again

[mitchnick]

24 minutes ago, psuhoffman said:

For northern MD crew.
 

I was holding out some hope that 2 things could save us. A sneaky h7 associated band on the northern fringe and maybe getting a couple inches then ice from wave 2.  Both of those hopes are fading. 
 

The h7 forcing is going north of us. It’s very disconnected from the main moisture feed, very similar to Jan 6. This will limit that bands effectiveness but could mean a 2-4” surprise for some places up in central PA that aren’t forecasted to get much snow at all.  But we are likely stuck in between again like Jan 6 only worse, I think there is more dry air and less healthy moisture transport with this one. 
 

The second option doesn’t look good either. The euro showed the mid level winds ahead of the amplifying second wave to be more s-n which eradicates the mid level cold faster and doesn’t allow for much WAA associated precip to break out ahead of the low. You need resistance to get lift and precip. If the warm just bullies the cold away you don’t get the lift.  The gfs and NAMs were showing a more SW-NE wind trajectory which lead to more cold resistance and a nice WAA thump snow. Alas they caved to the euro. 
 

My best guess for us is 1-3” from wave 1 and then maybe a little sleet and freezing rain to start wave 2 before it all gets washed away. 
 

If the coming period is what I expect our area should have our more typical geographical advantages in a more amplified pattern. 

Idk, Nam came north. Has you at 4"+. Not a bullseye, but a win.

[stormy]

Reports of 4 - 5 inches west of Roanoke in southwest Va. and southern W Va. in the Beckley region.

[primetime]

Carroll County just opted to close 3 hours early. Nice of them to wait for the work day to start, then make the announcement. 

[stormtracker]

Just now, SomeguyfromTakomaPark said:

No

Both NAMs look like slightly more QPF for DC.

Ok.  But I'm looking at both models and don't see much rain at the start

[NorthArlington101]

straight into my veins

[stormtracker]

3k looks about 7" in the city.  I'd cut it down to 5 and call it a day

[SomeguyfromTakomaPark]

1 minute ago, stormtracker said:

Ok.  But I'm looking at both models and don't see much rain at the start

Could just be the junky pivotal maps.  I don't think we lose an appreciable amount of QPF.

[LP08]

So the GFS has 11 in EZF and the NAMs have 5.  Should be a fun day for them!

[NorthArlington101]

Just now, stormtracker said:

3k looks about 7" in the city.  I'd cut it down to 5 and call it a day

That 8" jackpot is just for you

[clskinsfan]

2 minutes ago, NorthArlington101 said:

straight into my veins

yeah. It is probably a more realistic take. DC in a good spot for this one imo. Precip trajectory is really good for the city. Hope ya'll get buried. 

[stormtracker]

Just now, NorthArlington101 said:

That 8" jackpot is just for you

Yeah, I see.  I just know how the NAM suites are always too wet usually. 

[mitchnick]

12k

[aldie 22]

2 minutes ago, NorthArlington101 said:

straight into my veins

I mean even if it's not completely correct at hour 18 shouldn't this be pretty close?

[ers-wxman1]

12z NAM shows a later start time up through Loudoun/Fairfax/DC. -SN toward 20z vs 17z. Delayed onset closer to sunset now with heavier bands working in. Might see higher end of the 4-6, possibly 8” with cooler night time ground and more efficient accumulation. Soundings also showing decent lift in the dendritic snow growth region. 

[Bob Chill]

6 minutes ago, aldie 22 said:

Yeah that's north a little bit

It got my area pretty wrong. Widespread 2" down this way and at least 1" down along the NC border

[mappy]

32 minutes ago, psuhoffman said:

For northern MD crew.
 

I was holding out some hope that 2 things could save us. A sneaky h7 associated band on the northern fringe and maybe getting a couple inches then ice from wave 2.  Both of those hopes are fading. 
 

The h7 forcing is going north of us. It’s very disconnected from the main moisture feed, very similar to Jan 6. This will limit that bands effectiveness but could mean a 2-4” surprise for some places up in central PA that aren’t forecasted to get much snow at all.  But we are likely stuck in between again like Jan 6 only worse, I think there is more dry air and less healthy moisture transport with this one. 
 

The second option doesn’t look good either. The euro showed the mid level winds ahead of the amplifying second wave to be more s-n which eradicates the mid level cold faster and doesn’t allow for much WAA associated precip to break out ahead of the low. You need resistance to get lift and precip. If the warm just bullies the cold away you don’t get the lift.  The gfs and NAMs were showing a more SW-NE wind trajectory which lead to more cold resistance and a nice WAA thump snow. Alas they caved to the euro. 
 

My best guess for us is 1-3” from wave 1 and then maybe a little sleet and freezing rain to start wave 2 before it all gets washed away. 
 

If the coming period is what I expect our area should have our more typical geographical advantages in a more amplified pattern. 

Thanks for giving me hope lol. 2-3” is my call for my backyard. Probably on the lower end. 

[stormy]

NAM nest gives D.C. proper about 2 inches more than 06z.

[deer]

Going with 5" as my bar in Lake Ridge