Forecasting Skill going downhill ???

[Rich Thompson]

I figure it's time for an SPC forecaster to chime in here. Personally, I don't take offense to the original comments because I'm used to criticism. Actually, I'd be more concerned if nobody even noticed the SPC outlooks!

SPC outlooks are a bit different than a typical "chase cast" in that we have to consider continuity with previous outlooks, and we're looking at the entire conus for an 18-24 hour period. Continuity can be a challenge because forecasters don't always agree with one another. Also, POD is naturally given a little more emphasis than FAR (with some forecasters moreso than others). If one forecaster in the outlook sequence believes an event warrants a MDT/HIGH risk, then the outlook tends to stay at that higher category. There's more to be lost from an erroneous downgrade than an unnecessary upgrade, so we've got to be awfully certain when we go to downgrade a MDT/HIGH risk for tornadoes.

I'll admit that we've had a subpar spring with too many over-forecasts of tornado potential, but that's to be somewhat expected in a very slow spring.

Rich T.

 

[Billy Griffin]

Guess I don't have to add any comments on today, eh?
25-yr. event ??? Never saw it.

However, the caviat to this is that I'm happy for all those who did catch tornadoes Thursday.

This year has been really lousy, with some tough luck, so I guess I was just venting.

Hope we're all friends again. :wink:

 

[John Farley]

All the debate in this thread has been about OVERforecasting severe weather. I have to think that someone in Wisconsin is either chuckling about that or scratching their heads, given that over the past week, that area has received limited attention in outlooks, watches, etc. yet has had among the most SVR reports.

Today is a prime example - although there was a MSD issued, they never had a watch, yet if you look at the storm reports map, the density of reports today there is as high as anywhere else, including all of the places that had watches, and 2 of the 4 tornadoes reported today occurred there. (And if you look at the SVS's out of Green Bay, there may have actually been more than that.)

As many have pointed out, severe weather forecasting is an inexact science (Don't I know it from my own lack of success in forecasting/chasing this year!), and before we jump to the conclusion that events are being played up too much, we might consider that sometimes the forecasts have been off the other direciton.

 

[Chris Sokol]

Guess I don't have to add any comments on today, eh?
25-yr. event ??? Never saw it.

The message that you have such an issue with referred to the weekend...including Sunday. So you may want to "not add comments" until the period is over.

POTENTIAL WILL EXIST FOR 1 OR MORE SIGNIFICANT CENTRAL-U.S. SEVERE WX OUTBREAKS...BEGINNING AS EARLY AS THU BUT MORE LIKELY IN THE FRI-SAT-SUN PERIOD.

Trust me...I can beat this horse until it is labled "Elmers".

 

[Andy Wehrle]

I have to think that someone in Wisconsin is either chuckling about that or scratching their heads, given that over the past week, that area has received limited attention in outlooks, watches, etc. yet has had among the most SVR reports.

Today is a prime example - although there was a MSD issued, they never had a watch, yet if you look at the storm reports map, the density of reports today there is as high as anywhere else, including all of the places that had watches, and 2 of the 4 tornadoes reported today occurred there. (And if you look at the SVS's out of Green Bay, there may have actually been more than that.)

Next year on those days when there's just a marginal risk of tornadoes (2% according to SPC) I'm just going to drive up to Lake Winnebago and wait for the tornadic waterspout. :lol:

I find it highly ironic that even though nearly every textbook will tell you that southern Wisconsin has the most severe weather, nearly all the tornadoes this year have been in the GRB CWA, with only one in the MKX CWA (on March 30th). Looking back through the past few years, this also holds true. Only one tornado of F2 or greater intensity made it south of the Fond du Lac/Dodge County line in the last 5 years.

That aside, I did manage to get some decent storm pictures on Friday. I will have them up on the website in the next few days.

Back on topic, it seems they called for this event to start one day too late. They predicted a significant severe weather event in the Fri/Sat/Sun period, but how about Thursday eh? Besides, today and Sunday still hold potential for significant severe weather, and there could even be a few strong/violent tornadoes if everything goes right. 8)

 

[Billy Griffin]

You're forgetting the main thing I was focusing on in the forecaster's statement.... which is where I goofed in the title of the thread... "in more than 25 years." Was Thursday the most potent, widespread outbreak we've seen in over 25 years? Huh-uh.

Will Sunday be? That's awful darn hard to forecast considering this statement was made last Tuesday. :?

Yesterday could have (could have) been the day we were all waiting for, but too many mesoscale factors came into play and screwed the whole day up (unless you like watching flooding rains).

Seems apparent that tomorrow will have the same potential to be a very good day with tornadoes likely in Oklahoma, but "but".... there could also be earlier convection to just blow the whole thing.

So with that said, all in all, after 743 miles yesterday and finally getting to see a few lightning strikes on the way back from the round trip drive of Norman to Elk City to Amarillo to Lubbock to Vernon to Lawton and back to Norman, ummm... it sure would be nice to see one more big event before all the wheat is cut.

Started the year three for three, now zero for the past five. :cry:

Guess we'll just have to hope and see what tomorrow brings. I hope today's convection is minimal at best and the atmosphere has a little more time to recover before tomorrow. :wink:

BTW: the dead horse is a lost cause. Besides, Elmers uses the COW photo, not the horse. LOL

 

[Jeff Snyder]

You're forgetting the main thing I was focusing on in the forecaster's statement.... which is where I goofed in the title of the thread... "in more than 25 years." Was Thursday the most potent, widespread outbreak we've seen in over 25 years? Huh-uh.

Billy,

You are misquoting the original forecaster. He didn't say it'd be the most impressive outbreak in the US in the past 25 years, as you are implying (or directly stating)! He said that the upper-air pattern was AS potent as any he's seen in HIS 25-yr experience. This is NOT the same as saying the best outbreak "in more than 25 years" (as directly quoted above). From a synoptic standpoint, this pattern DOES look like a big tornado producer, but the mesoscale environment (which is not forecastable 3-5 days in advance) can really 'make or break' an event. We've seen this time and time again -- it's nothing new. So far, it's seems that the mesocale environment has been a "break" in the event. If convection had held off yesterday morning and waited until mid-late afternoon, I think there could have been significant tornadic supercells in the eastern Panhandles and western OK (low-level shear was very impressive, steep-lapse rates aloft, etc). Upper-level flow would have probably been sufficient as well.

The "First 10 Days of May" 2003 was as impressive SYNOPTIC environment as you really get. Strong western US trough, wide open Gulf, strong (but breakable) cap, etc etc etc. That said, some of those outbreaks during that time period could have turned out quite a bit differently if there had been widespread morning convection, etc.

Are you going to start a "Good Job NWS" for an event which they correctly forecast days ahead of time?

 

[Billy Griffin]

Why sure, hindsight is always 20/10 :wink:

Whatever quote it was, that's the only thing I'm trying to say, although I'll admit I may have what one of the other postings was earlier... "poor brain to fingers coordination". LOL

The point being, it's hard to say what type of significant outbreak will come into play, if any. Certainly hope so. Just as fearful as everyone else on some little something coming up and ruining the day.

Is there any saving 2005 ??? :?

Hey, if the guy turns out right, I'd like to give him a big hug and have him be my chase partner... although I'm not sure he'd / she'd share the same sentiment. :shock:

We'll see, however it turns out, I sure hope tomorrow is fun. You know the funny, or weird, thing is that SPC seems to now be downplaying the event, with only slgt. Hatched and 25% - still liking that though !!

 

[Joe Zemek]

Aha, Alex touched on what I hadn't noticed in the thread and will hereby post: 6/4 was most likely a HIGH RISK day specifically b/c the risk area centered Kansas City, and also included Topeka, St. Joseph, bordered Omaha, & other areas of denser population.

It's hard to remember at times that the SPC is forecasting to protect the public, not how good a chase day we will have. As someone who was hoping for long lived tornadoes that day and instead got avg. updrafts, avg. LL shear and zero visibility, I had to remember this that day. When there's a large population involved, I think we can expect a higher risk prob than normal b/c more people will experience svr wx. Looking at the reports, imagine if the sfc boundary that the main TOR producer in NE KS/NW MO moved along was located further S into KC metro. Probly best that the risk remained HIGH.