Beginning Descent into Chase Season 2014

[Mark Ellinwood]

Thanks for the link to that discussion, Mark!


^^^ My picture goes next to this in the dictionary of ignorance.

I've completely avoided 06Z/18Z GFS up to now.

Heh, don't beat yourself up too much for it. There's still degreed mets who think the 06z/18z runs are complete junk. It was certainly a valid argument as late as the early 2000s, and that legacy has still managed to get carried through the years despite the ever-tightening gap between the runs.

 

[Jeff Duda]

I have been among those to ignore the 06Z/18Z runs, but not always. While I thought they would be a little less accurate due to not having the regular suite of balloon launches for UA IC analyses, I have come to question the need for a global ensemble run every 6 hours. No other operational center in the world does that. Just think of the computer resources that could be saved and used for other purposes if the GFS was not run at 06Z and 18Z!

 

[Joe Pudlik]

I have come to question the need for a global ensemble run every 6 hours. No other operational center in the world does that. Just think of the computer resources that could be saved and used for other purposes if the GFS was not run at 06Z and 18Z!

There are many that agree with this, including myself.

There is really no need for the 6/18z runs when there are so many short term models in place that would fill the "void".

 

[Jeff Duda]

There is really no need for the 6/18z runs when there are so many short term models in place that would fill the "void".

It goes beyond that. Is it that big of a deal to capture the evolution of a possible major synoptic scale mid-latitude cyclone at day 7 over the course of 6 hours of forecast hour change? While it's likely that some substantial changes would occur, so what? It's still 6.75 days away 6 hours later.

I have heard of a number of fairly major changes going on at NCEP regarding the models over the next few years. One that I was told at least a year ago now was that eventually the NAM and RAP would be essentially combined into a single mesoscale model that would run out to hour 84 or so every hour. Then, the current HRRR would sort of take over as the previous RAP, but at convection-allowing resolutions. Finally, NCEP is already running a parallel GFS at 13 km that will become the new resolution by 2015 I think. Beyond that is even more cool things they plan to do with the modeling branch.

 

[John Wetter]

Another great tool all of you might be interested in is the HopWRF Climate Forecast System Ensemble page. Just recently we added severe weather probabilities to it as well. This could be really handy with the 3-6 week forecasts looking at what the predominant setup might look like for a week at a time.

The HopWRF CFS Ensemble is a 20 member ensemble of the CFS model. More details can be found at http://cfs.hopwrf.info.

 

[chrisbray]

Prospects for anything in the next couple weeks looking bleaker with every run.

 

[Marcus Diaz]

And I must be the only one happy with that? I'm hoping for a late season start like 2010 was. April 20 was the first real good day.

 

[Jason Boggs]

For some reason, I think it might be a second half of May into June kind of year. Nothing to base that off of besides a gut feeling.

 

[Jon Strebler]

Having the model runs come out an hour later is a sure sign that chase season is coming soon even if the outlook for the next two weeks is bleak.

 

[James Gustina]

And I must be the only one happy with that? I'm hoping for a late season start like 2010 was. April 20 was the first real good day.

I'm still smarting from last season's series of unfortunate events which is why I was gunning for an early start. But if April ends up spitting out a string of days like 2010 then I will be more than satisfied.

 

[chrisbray]

I'm fine with it really starting in april too, I just have a bit of cabin fever up here in Illinois. I just need it to not be Winter. I miss warmth and I miss storms!

 

[Sean Mullen]

Having the model runs come out an hour later is a sure sign that chase season is coming soon even if the outlook for the next two weeks is bleak.

Not to mention that now we have that extra hour of daytime heating!

 

[Jeff Duda]

Another great tool all of you might be interested in is the HopWRF Climate Forecast System Ensemble page. Just recently we added severe weather probabilities to it as well. This could be really handy with the 3-6 week forecasts looking at what the predominant setup might look like for a week at a time.

The HopWRF CFS Ensemble is a 20 member ensemble of the CFS model. More details can be found at http://cfs.hopwrf.info.

Bookmarked. That's a really cool suite of graphics you guys put together. Thanks for making that. Although several types of graphics have me confused (like maximum of minimum PW and such). I don't see any explanation of those on the site.

 

[John Wetter]

Bookmarked. That's a really cool suite of graphics you guys put together. Thanks for making that. Although several types of graphics have me confused (like maximum of minimum PW and such). I don't see any explanation of those on the site.

Hi Jeff, for that example, it would be given the 20 member ensemble, what is the maximum value from all of the members for the minimum PW. So what is the highest output for all of the lows. It's meant to give you an idea of the most conservative of the low PW value, etc. Another way of giving the 'best case' or 'worst case' scenario for different values.

 

[James Gustina]

GFS doesn't seem particularly favorable for much of anything besides run-of-the-mill weather into next week. It shows a compact cutoff low coming onshore in California but it quickly gets absorbed into a broad longwave and doesn't seem to put down any decent precip anywhere on it's travels. It looks like troughing over the east coast persists towards the end of the period and the Plains get either stuck under a high pressure dome or end up on the periphery of the systems. Bring on April already.