high risk

I still haven't seen any guidance today that suggests that SVR is possible in this area, except for those in southern PA or possibly western and northeastern MD.    We might, however, get some thunder very early Monday.   SPC might retain the MRGL where it already is for continuity, but the timing for most of us for this event is way off.

2 hours ago, Eskimo Joe said:

Sunday could have a few decent storms riding a remnant EML in northwest flow. These setups can produce.

          Definitely can!    I think that the timing isn't good for most of us, although there appears to be a signal for some earlier storms dropping southeast into northeastern MD.

7 hours ago, EstorilM said:

Wow what a night (unexpected!) 

What an exactly happened from a meteorological perspective? Aren’t things usually pretty dry and stable hours after a front has passed? 

  You only need to go back one page in this discussion to read about the setup. 

7 hours ago, high risk said:

Hoping for some thunder later tonight.   Seems to be some general consensus for a band of showers during the dinner hours, and then a second round of more scattered but also heavier cells closer to midnight.  Lapse rates will sharpen a bit as the shortwave swings through, so I don't think that we can rule out some lightning.

        Multiple CAMs nailed this.   Radar looks very convective, with some lightning strikes to our northwest.

Hoping for some thunder later tonight.   Seems to be some general consensus for a band of showers during the dinner hours, and then a second round of more scattered but also heavier cells closer to midnight.  Lapse rates will sharpen a bit as the shortwave swings through, so I don't think that we can rule out some lightning.

Kinda glad that this wind is occurring.   Even though it's long after the MDT was dropped, it will help verify the threat in the public's eye and remove some of the "cry wolf" narrative.

2 minutes ago, Kmlwx said:

Yeah could definitely see that. I think the big questions are how much recovery happens and how intense that frontal line gets. I could see it being anything from robust/gusty showers to a major damaging wind event. For now I'm holding back on sounding any alarms obviously. 

We will see what SPC thinks in the update coming soon. If they trim back probabilities for areas that have seen the line - we'll know their thinking we are "done" 

           They rarely trim things back unless there is a huge clear-cut signal to do so, with strong model consensus.  

5 minutes ago, yoda said:

True... but the text posted above also mentions potential for strong long track tornadoes 

Oh, absolutely.  The ceiling for this event is way higher than we usually see around here.   I’m just pointing out that we shouldn’t be shocked if this ends up way short of its potential.   The 00z CAM suite was far from a slam dunk. 

4 minutes ago, yoda said:

We are still a go per SPC new Day 1

   It’s still a go in terms of the categories and percentages that they’re rolling with, but the actual text mentions multiple ways this could bust.  

I don’t see this as getting to a high risk tomorrow.   If you read the updated day 2, they note a number of potential problems.   Again, the ceiling for this event is very, very high.  But the floor, while still significant, is lower than some people realize. 

Oh, and anyone trying to nail down the timing should never look at the NAMs.  They’re always a couple of hours late with these events.   

13 minutes ago, yoda said:

I nominate @high risk to replace Ellinwood

Hahaha.  I don’t want to move on that chart.   Maybe it’s because I’m out of town, but while I completely buy the high-end scenarios, there are a still a few things I don’t like about the setup. I would gladly exchange some of the shear to get more instability.  Yes, there is still some cape, and maybe it’s enough, but the forecast soundings have tall, very skinny cape which sometimes doesn’t get the job done.   That said, it’s tough to ignore that a forced line of convection will roll through in an environment that can certainly bring some big wind to the surface.  

The high end scenario is still very real.  The fail scenario is still very real.  

21 minutes ago, Rhino16 said:

Are there any notable events where recovery occurred from showers earlier in the day? Is it something we struggle to do around here?

Yes and yes.      The failures are way too many to note, but a famous day when we successfully recovered is the La Plata event. 

4 minutes ago, Eskimo Joe said:

We'll see. I would favor DC and points south for torandoes, maybe some rogue QLCS thingy in MD through Central PA.

I think that’s reasonable, although climo says (and guidance agrees) that the best tornado threat will be even further south. 

The high end potential is definitely there, but two things stand out  1) a clear trend towards earlier timing    2) a lot of guidance showing clouds and showers well ahead of the main forcing.  With the right timing, the early convection could be supercells, but the trend towards an earlier event opens the door to insufficient time to recover after morning showers. 

1 minute ago, Eskimo Joe said:

70 - 125 kt shear on a neutral to negatively tilted trough in March is a recipe for a decent event.

But is that too much shear for the very modest cape?    

It’s going to happen because I have a flight arriving at BWI that evening.   But seriously, you all have nailed it:   Shear will be off the charts, but early spring setups fail a lot here due to the strength of the system causing widespread showers and clouds.  

The forecasted accumulated snow depth maps are the only relevant images for this event.

24 minutes ago, TSSN+ said:

The area to watch 

 

   Agreed.  HRRR has a pretty good handle on it, and while I'm still not totally sold on the severe threat, it's moving into a more favorable environment.

Friendly reminder that snow accumulation does not reflect what the model thinks will stick.   It reflects the amount of QPF that the model has falling as snow.   The issue of why the QPF has over 0.50" of liquid falling at the tail end of this event is, however, a fully legit question.

42 minutes ago, TSSN+ said:

Models don’t show much action today. 

  Yeah, this is the problem.    The shear is good, but how many storms will form?   HRRR pops a couple of cells, but it thinks that we're still going to the mid 80s today.

Well, hello HiResW FV3!   

Ugh.  The evening CAMs have really backed off, and the NAM Nest never liked it from the start.   If this idea is correct, any severe threat may be confined to along I-70 and north.

2 hours ago, Kmlwx said:

I know there's a lot of mixed thoughts about the CIG hatching - but this is probably where it is going to have a good amount of utility regardless of how confused people are. 

Bear in mind that prior to the new outlooks - this map would just be a straight 2% tornado prob for us. 

         Yeah, I like the 2% hatched.    It reflects that there right now is an overall low threat of tornadoes in this area, but if we were to get one, it could be a strong one.