Let's discuss the Storm Prediction Center (SPC) (1 Viewer)


WesL

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In my honest opinion, I feel that the SPC has been a little off track for the past few events. Is anyone aware of any recent changes at the SPC that might be contributing to some of this?

What have you noticed?
 

Matt Grantham

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Honestly it's not just the past few events. The introduction of numerous convective allowing models and simulated reflectivity has been detrimental. As with forecast soundings, we should never take one of these models at face value. They are supposed to be the experts and read between the lines, knowing these weaknesses of these models and using that to their advantage.
 
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To be fair, some these events have seemed particularly tricky to forecast (as in model performance has been abysmal with very little consistency or agreement, sometimes even the morning of), but then again that's what they're here to do.

I think there's some degree of disconnect between forecasting a favorable parameter space, and forecasting whether storm spacing and mode will allow them to take full advantage of it.

They did very well with the outlooks on February 28th. March 6th overachieved the outlook forecast somewhat but not drastically. However I think a 15% hatched MDT tor risk would have adequately covered both high risk days this year. IMO to go with high risk (based on tornado probs) you need to be highly confident in not only an exceptionally favorable parameter space but also that storms will be sustained while remaining discrete with uncontaminated inflow, lack of left split collisions, upscale growth, etc.
 
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WesL

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For the record, I'm not complaining. I just know there is significant fatigue with some of their calls. I know they have a super tough job and it is easy to be a Monday morning quarterback with some of this stuff. I was just wondering if conditions had changed at the office or if forecasting severe weather has become a bit harder lately.
 

Kory

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For the record, I'm not complaining. I just know there is significant fatigue with some of their calls. I know they have a super tough job and it is easy to be a Monday morning quarterback with some of this stuff. I was just wondering if conditions had changed at the office or if forecasting severe weather has become a bit harder lately.
Monday morning quarterbacking is a huge part of science (of course with constructive criticism). Going back and analyzing what went right but more importantly what went wrong and how to fix it next time is very important. It's basic synoptic analysis that has been flawed and it doesn't seem like they're striving to fix what they've struggled with (Gulf Coastal convection with upper level divergence of the 300mb jet for example).
 

JWard87

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I think it might be more of a be over-prepared approach to what is happening. Correct me if I'm wrong, but the SPC has been a little more touchy with the magenta as of late. The models consistently have showed a threat each time that, IMHO, have been on par with previous severe WX events.

All things aside-- it's a damned if you do, damned if you don't kinda job.
 
@Matt Grantham, you pointed something out earlier that I found interesting. When the local offices post their threat area graphics, they now have to coincide with the outlook SPC puts out, even if you disagree with it or see it a little differently.

That creates and interesting situation. On the one hand, having them the same provides uniformity and reduces confusion that the general public (who aren't Weather geeks) may have. On the other hand, it doesn't allow the local offices to interpret things specifically for their coverage area, which they are able to focus on more specifically and understand more about.
 

Matt Grantham

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@Matt Grantham, you pointed something out earlier that I found interesting. When the local offices post their threat area graphics, they now have to coincide with the outlook SPC puts out, even if you disagree with it or see it a little differently.

That creates and interesting situation. On the one hand, having them the same provides uniformity and reduces confusion that the general public (who aren't Weather geeks) may have. On the other hand, it doesn't allow the local offices to interpret things specifically for their coverage area, which they are able to focus on more specifically and understand more about.
It's a policy that began earlier this year that I vehemently disagree with for reasons that are being borne out as we speak.
 
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I think they're just about 0-fer with Day 2 moderate risks thus far this year. Maybe everyone (including them) should just step back and admit that even with all the new models and model "upgrades," we still don't know much about what the atmosphere will do beyond about 12 hours at most, especially WRT severe wx and winter wx.
 

Kory

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I think they're just about 0-fer with Day 2 moderate risks thus far this year. Maybe everyone (including them) should just step back and admit that even with all the new models and model "upgrades," we still don't know much about what the atmosphere will do beyond about 12 hours at most, especially WRT severe wx and winter wx.
They just need to start doing synoptic analysis. WAY back last Wed/Thurs, there was a large signal for a heavy rain event/MCS for today. Here is the GFS on Saturday valid today. BIG upper level divergence, which rarely results in widespread severe, but more so widespread heavy rainfall...which is precisely what we're seeing.

Does anyone know how to do analysis from a top down approach?

 

JayF

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I think we should remember that the SPC Outlooks are guides at best. I think the TV Meteorologists did a good job of explaining different possible scenarios that could have happened for Thursdays storms. I know some people will not understand it and will complain about their not being severe weather when it is in the forecast.

We still have to be careful with overhyping an event because people will get complacent and not pay attention. The important thing is to remind people to always have a weather radio and to stay weather aware by using apps on their phones that will provide alerts or listening to tv and radio when severe weather is possible.
 

HazardousWx

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Their needs to be a way for the SPC to note on the graphics "conditional" or something to that effect much like they do "see text" when there is a minor concern for an area but not enough to shade it in. While their products are not intended for the average person to view, people basically ARE viewing them on local NWS pages and TV graphics.

We are in a pattern of severe weather outlooks for storms every 2-3 days lately. In our area, they largely have not verified. I have the same fears listed above that people are getting cynical about these. In fact, I find it hard to pass along a forecast when we are barely in the marginal or slight risk area because I'm not sure that everyone knows what that means, really.
 

pritchlaw

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I think they're just about 0-fer with Day 2 moderate risks thus far this year. Maybe everyone (including them) should just step back and admit that even with all the new models and model "upgrades," we still don't know much about what the atmosphere will do beyond about 12 hours at most, especially WRT severe wx and winter wx.
This is dead-on accurate. Exactly right.
 
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Actually, perhaps I should have held my tongue a bit. Although the MDT risk over AL got dropped, and rightly so, the ENH risk over GA was pretty much spot on.
 

WesL

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There are some new forecasters there. SPC lost a few longtime forecasters to retirement and sadly one of my favorite forecasters Jon Racy passed away from cancer
Ah that was what I was wondering
 

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