Jump to content
  • Member Statistics

    17,588
    Total Members
    7,904
    Most Online
    LopezElliana
    Newest Member
    LopezElliana
    Joined

February 12-13 Storm IV, Model Discussion


stormtracker

Recommended Posts

  • Replies 1.2k
  • Created
  • Last Reply

I'm west of 95 and expect to contend with a period of sleet. Everyone should except way far west.

I understand Matt setting expectations but as an absolute statement he's wrong, there's an X probability chance 95 stays snow.

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

I understand Matt setting expectations but as an absolute statement he's wrong, there's an X probability chance 95 stays snow.

Sent from my iPhone

 

there's a non-zero chance of a lot of things happening -- continuously saying it doesn't make it more likely to occur

Link to comment
Share on other sites

I'm almost positive all the way to bay north of Annapolis will be absolutely buried by morning with 6-10+. The latest short range guidance looks phenomenal. I am not even thinking in terms of the 3/6 situation, this set-up is really not too analogous. All things considered, we look primed to get crushed. LL cold should hang in a bit longer in accordance with what Matt is saying. The antecedent airmass is fresh and impressive. Sub 30 highs make for a great stage to be set. Lower dews mean everyone will evap a bit, and in the exceptional rates that some could see, even cool dynamically. 

 

That was sort of my point earlier, although I think us on the Annapolis side would more likely average in the 4-7" end rather than 8-10".  I think we all realize that the majority of the snowfall will be the front-side variety, which in this environment an amount centered ~6 inches is certainly plausible given the thermals and UVV's through 09-12Z.  Our amounts will certainly be curtailed by either the elevated warm layer and/or dry slotting/reduced pcpn rates.  Honestly, if I wake up to 6-8" of snow with the transition to light sleet, I won't care.  That's still a pretty good hit, and any hit with the back end CCB (1-2, with 2-4" being the "boom" later tomorrow), would be additional candy.

 

I know in deepening systems, what happens aloft obviously will dictate the low levels and SLP track.  However, right up until the end of this event I still suspect the colder Bay and Atlantic shelf waters will play a role here. Obviously not with the thermal profiles aloft, but all else being equal, I would think the surface low would track a little farther east from what the EC has been showing , i.e. closer to those warmer Gulf Stream waters. That's obviously more of a wishcast if we get closer aloft sooner than later, but still, obviously initially that coastal/baroclinic boundary is going to be farther away from us than what we typically see..

Link to comment
Share on other sites

It looks like the 18z H5 almost closed at hr. 42. That probably explains why the GFS is more east, right. But it did close at hr. 39 on the 12z run. So the GFS is definitely not in the Euro's camp (never was) but less so now.We might need the GFS to score the coup to have less mixing.

We're likely going to mix regardless of track, so why sacrifice QPF and rates just to remain snow a little longer? Weaker, offshore low = reduced rates hence warmer sfc/less accums..stronger inland low = increased rates/dynamics/QPF, but possibly more mixing..I'll gladly take the latter. I hope the GFS busts badly and we see an ECMWF-like track.

Link to comment
Share on other sites

Not scientific, but this just doesn't feel like a scenario where we see major mixing. It is mid-February and was plenty cold today. If we can't stay mostly snow in this we really suck.

the high position sucks if nothing else.  tho i kinda doubt we're going to get any rain of consequence even in dc.. drizzle maybe. 

Link to comment
Share on other sites

We're likely going to mix regardless of track, so why sacrifice QPF and rates just to remain snow a little longer? I hope the GFS busts badly and we see an ECMWF-like track.

Well if the EURO is right and with the previous statement about the trough closing off earlier, the storm could come too far west, if the EURO latest guidance is accurate.

Link to comment
Share on other sites

Well if the EURO is right and with the previous statement about the trough closing off earlier, the storm could come too far west, if the EURO latest guidance is accurate.

On the Euro we still get a 1.2-1.5" of QPF, mostly snow even here in DC..plus some crazy upper dynamics and sfc wind gusts around 30mph..verbatim.

I'll take that over something weaker and less dynamic.

Link to comment
Share on other sites

the high position sucks if nothing else.  tho i kinda doubt we're going to get any rain of consequence even in dc.. drizzle maybe. 

 

Yes.  In-situ damming will be prevalent, though probably not enough to close off a secondary surface high to our north.  

 

Again, if the EC is right with the more westward track, then hopefully it'll be right with the front-end thump for us along/east of I95. 

Link to comment
Share on other sites

the high position sucks if nothing else.  tho i kinda doubt we're going to get any rain of consequence even in dc.. drizzle maybe. 

I knew it when I walked out to get coffee this morning.. it is pretty darn cold.. it is persistent cold air.. that seems to be overperforming

Link to comment
Share on other sites

the high position sucks if nothing else.  tho i kinda doubt we're going to get any rain of consequence even in dc.. drizzle maybe. 

 

agreed...though I am concerned about sleet...the problem with these short term models is they are warm....now the RAP does have a warm bias...it had the 850 line past Tysons corner on 2/5/10...lol

 

but when these 0.20"/hr totals come in, we are +1 at 900 mb...I doubt that is snow....we have to be real careful about hugging uber wet models since along with the sick rates comes mixing....we can probably do ok with a shallow warm nose of like +0.4, but beyond that scares me....I don't want to go to heavy sleet as soon as we start ripping

Link to comment
Share on other sites

agreed...though I am concerned about sleet...the problem with these short term models is they are warm....now the RAP does have a warm bias...it had the 850 line past Tysons corner on 2/5/10...lol

 

but when these 0.20"/hr totals come in, we are +1 at 900 mb...I doubt that is snow....we have to be real careful about hugging uber wet models since along with the sick rates comes mixing....we can probably do ok with a shallow warm nose of like +0.4, but beyond that scares me....I don't want to go to heavy sleet as soon as we start ripping

 

12z euro sounding said 850s were 0.2 to 0.5  between 12z and 18z tomorrow.  It might be close enough to be ok if it is a little warm

Link to comment
Share on other sites

agreed...though I am concerned about sleet...the problem with these short term models is they are warm....now the RAP does have a warm bias...it had the 850 line past Tysons corner on 2/5/10...lol

 

but when these 0.20"/hr totals come in, we are +1 at 900 mb...I doubt that is snow....we have to be real careful about hugging uber wet models since along with the sick rates comes mixing....we can probably do ok with a shallow warm nose of like +0.4, but beyond that scares me....I don't want to go to heavy sleet as soon as we start ripping

 

I haven't looked at the specifics of the latest short term models (RAP), or even the EC thermals.  BUT, are we really thinking that elevated warming would move in as early as 8-9Z?  That's like less than 12 hours from now.  I had always thought DCA was good through 12Z.  Maybe that's NAM hugging, but still...

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...