usedtobe Posted January 23, 2012 Author Share Posted January 23, 2012 Great discussion, Wes. It will be interesting to see how some of the differences between the GFS ensembles and ECMWF ensembles are resolved and how February actually plays out. Unfortunately, I don't believe there will be a dramatic weakening of the current La Niña event. The ensemble runs still have not converged on a solution. However, both the euro ens mean and the 06Z ens mean now take the ao weakly positive. They still differ on the PNA ridge position with the euro holdign it negative and the gefs positive. That makes it tough to knwo how to play early feb. Link to comment Share on other sites More sharing options...
mitchnick Posted January 23, 2012 Share Posted January 23, 2012 since we are talking models, today's CFS continues to cut back on the above normal temps in the SE US for FEB and the =.5-+1K area has just about reached DCA http://www.cpc.ncep....s3/usT2mMon.gif 850 temps for the month are almost within normal http://www.cpc.ncep.noaa.gov/products/people/wwang/cfs_fcst/images3/usT850Mon.gif Link to comment Share on other sites More sharing options...
usedtobe Posted January 23, 2012 Author Share Posted January 23, 2012 since we are talking models, today's CFS continues to cut back on the above normal temps in the SE US for FEB and the =.5-+1K area has just about reached DCA http://www.cpc.ncep....s3/usT2mMon.gif 850 temps for the month are almost within normal http://www.cpc.ncep....3/usT850Mon.gif They have actually warmed the plains and have most of the country warm. I wonder how much the cooling over the southeast is based on the early part of the month or does it not distingiush. I'm not familiar with it enough to know what the time steps are on the forecast. Maybe DTK can chime in. Link to comment Share on other sites More sharing options...
Bob Chill Posted January 23, 2012 Share Posted January 23, 2012 Wes, no clear signals seems to be happening for the start of next month. If anything, alot of mixed signals are going on. This Feb may be a battleground month with a progressive flow and equal chances at warm or cold overall. All the models show a +pna in some form or another. Not locked in or anything but 2-3 day shots of cold in the east with pac energy embedded in the flow. Wouldn't take much for a 2-4 event to come to life imo. Link to comment Share on other sites More sharing options...
usedtobe Posted January 23, 2012 Author Share Posted January 23, 2012 Wes, no clear signals seems to be happening for the start of next month. If anything, alot of mixed signals are going on. This Feb may be a battleground month with a progressive flow and equal chances at warm or cold overall. All the models show a +pna in some form or another. Not locked in or anything but 2-3 day shots of cold in the east with pac energy embedded in the flow. Wouldn't take much for a 2-4 event to come to life imo. The last 3 gefs ens mean runs also take the ao and nao positive at the same time. That's not terrible if you can get a vort to dig to our south due to the ridge shifting east and amplifyinng at the same time. I'd be much happier somethng to hold in high pressure to our north but it's not terrible. Link to comment Share on other sites More sharing options...
mitchnick Posted January 23, 2012 Share Posted January 23, 2012 They have actually warmed the plains and have most of the country warm. I wonder how much the cooling over the southeast is based on the early part of the month or does it not distingiush. I'm not familiar with it enough to know what the time steps are on the forecast. Maybe DTK can chime in. if you look down at the bottom group Wes, it has groups of E1, E2 and E3 E1 is from an old run and E3 the most recent; it says the date of the initial conditions so it has definitely been geeting cooler (or at least less AN) http://www.cpc.ncep....wwang/cfs_fcst/ Link to comment Share on other sites More sharing options...
brad1551 Posted January 23, 2012 Share Posted January 23, 2012 Mitchnick, Hey I am learning lots a great stuff from this blog forum. I am starting to learn about the CFS and the data onset it gives. I could not help and look at what your asking Wes about. To me it looks like it is getting cooler too. Then the normal spike up by summer and fall. Then who knows for me. Thanks for the link! Link to comment Share on other sites More sharing options...
usedtobe Posted January 23, 2012 Author Share Posted January 23, 2012 Brad, Mitch, Sure is's a little cooler but basically has the entire country warm making it hard to get much cold air over us. My question remains what are the time steps of the models. Is there a cool period at the beginning of the month that gives way to warm. Lots of questions. I also wonder what the latest euro weeklies are doing Link to comment Share on other sites More sharing options...
Feb Posted January 23, 2012 Share Posted January 23, 2012 Brad, Mitch, Sure is's a little cooler but basically has the entire country warm making it hard to get much cold air over us. My question remains what are the time steps of the models. Is there a cool period at the beginning of the month that gives way to warm. Lots of questions. I also wonder what the latest euro weeklies are doing I haven't seen anything posted about them yet Wes. They do come out on Mondays and Thursdays. Link to comment Share on other sites More sharing options...
usedtobe Posted January 23, 2012 Author Share Posted January 23, 2012 I haven't seen anything posted about them yet Wes. They do come out on Mondays and Thursdays. Thanks, I was hoping Adam might have posted something. Link to comment Share on other sites More sharing options...
Feb Posted January 23, 2012 Share Posted January 23, 2012 Looking at the weeklies, it seems like the +PNA may be for real. They have a decent +PNA and even -NAO at that point..although I think the -NAO is more shaky, based on late behavior. Week 4 has an overall -AO look with higher heights across the North Pole. Also ridging into AK. Not very cold verbatim for these parts, but that upper level would probably be ok for these parts. Thanks, I was hoping Adam might have posted something. Not from Adam, Wes, but from Scott in the New England thread. Sounds okay for them, not sure about us. Link to comment Share on other sites More sharing options...
Ellinwood Posted January 23, 2012 Share Posted January 23, 2012 Weeklies = torch. temps fall back to just on the + side of normal by week four... but that's week four. Link to comment Share on other sites More sharing options...
brad1551 Posted January 23, 2012 Share Posted January 23, 2012 Thanks Ellinwood and thanks Wes! "The Beat Of The Drum Goes On". Link to comment Share on other sites More sharing options...
dtk Posted January 23, 2012 Share Posted January 23, 2012 Brad, Mitch, Sure is's a little cooler but basically has the entire country warm making it hard to get much cold air over us. My question remains what are the time steps of the models. Is there a cool period at the beginning of the month that gives way to warm. Lots of questions. I also wonder what the latest euro weeklies are doing The CFS (v2) is a pretty complex system, and it's going to be impossible for me to explain in only a few short words. The dynamical model that is used is a low resolution version (T126L64) of the GFS dynamics, with alternate physics (tested/tuned to be more appropriate for seasonal/climate), fully coupled to an interactive ocean model. Every cycle (00, 06, 12, 18 UTC) there is an analysis created (from a coupled version of our GDAS), which is used to initialize a single 9-month run of the CFSv2 model. [As an aside, and ensemble of 45-day and single season runs are also generated, but that's not the point here]. I think the products being discussed here are all from the 9-month runs. Basically, things are grouped into time-lagged ensemble forecasts. The E3 grouping is simply a time-lagged, 40 member ensemble using ICs from the past 10 days. The E2 group is then from 10-20 days ago, and so on. I think Mitch is really pointing out the trend in the sequence of ensemble forecasts (how useful this is, I'm not entirely sure). I suppose this would be analogous to watching the trend in the anomalies in the GEFS forecast for several consecutive cycles/days.....though I wonder if the "trend" is truly meaningful in this context. Interestingly enough, the Lag-0 probability basically has the mid-Atlantic in an equal chances scenario: http://www.cpc.ncep....mProbMonHD0.gif You can also look at a break down of a week's worth of members here: http://www.cpc.ncep..../monthPlot.html Including the forecast for Feb. here: http://www.cpc.ncep....mMonSummary.gif This doesn't give much information about which part of the month is forecast to be cold/warm, etc., but does give some information regarding the volatility within the ensemble (from day to day). Link to comment Share on other sites More sharing options...
Ji Posted January 23, 2012 Share Posted January 23, 2012 Weeklies = torch. temps fall back to just on the + side of normal by week four... but that's week four. I though they were cold last week for week 4 with -nao Link to comment Share on other sites More sharing options...
mitchnick Posted January 23, 2012 Share Posted January 23, 2012 Weeklies = torch. temps fall back to just on the + side of normal by week four... but that's week four. meh, they'll be different in 72 hrs that's the problem with coming out twice a week Link to comment Share on other sites More sharing options...
brad1551 Posted January 23, 2012 Share Posted January 23, 2012 DTK, I wrote a response from my iPhone and I do not think it went through. I want to say thanks for the awesome write up you gave. I am getting into the CFS as we speak in school. People like you keep my mind sharp and full of thought. Most of all I gain knowledge from people like you and I am most grateful for. Thanks again DTK and I am going to get in all of the sites tonight. Bookmarked and I am ready to learn even more. I get excited reading and learning from people like you. Thanks again! Link to comment Share on other sites More sharing options...
usedtobe Posted January 24, 2012 Author Share Posted January 24, 2012 The CFS (v2) is a pretty complex system, and it's going to be impossible for me to explain in only a few short words. The dynamical model that is used is a low resolution version (T126L64) of the GFS dynamics, with alternate physics (tested/tuned to be more appropriate for seasonal/climate), fully coupled to an interactive ocean model. Every cycle (00, 06, 12, 18 UTC) there is an analysis created (from a coupled version of our GDAS), which is used to initialize a single 9-month run of the CFSv2 model. [As an aside, and ensemble of 45-day and single season runs are also generated, but that's not the point here]. I think the products being discussed here are all from the 9-month runs. Basically, things are grouped into time-lagged ensemble forecasts. The E3 grouping is simply a time-lagged, 40 member ensemble using ICs from the past 10 days. The E2 group is then from 10-20 days ago, and so on. I think Mitch is really pointing out the trend in the sequence of ensemble forecasts (how useful this is, I'm not entirely sure). I suppose this would be analogous to watching the trend in the anomalies in the GEFS forecast for several consecutive cycles/days.....though I wonder if the "trend" is truly meaningful in this context. Interestingly enough, the Lag-0 probability basically has the mid-Atlantic in an equal chances scenario: http://www.cpc.ncep....mProbMonHD0.gif You can also look at a break down of a week's worth of members here: http://www.cpc.ncep..../monthPlot.html Including the forecast for Feb. here: http://www.cpc.ncep....mMonSummary.gif This doesn't give much information about which part of the month is forecast to be cold/warm, etc., but does give some information regarding the volatility within the ensemble (from day to day). Daryl, Thanks. I found the summary really interesting. It does give a lot of info about how predictable it is and the forecasts suggest not very. How some runs earlier had the southeast warm and the plains cold and now you have the opposite doesn't inspire much confidence. Link to comment Share on other sites More sharing options...
dtk Posted January 24, 2012 Share Posted January 24, 2012 Daryl, Thanks. I found the summary really interesting. It does give a lot of info about how predictable it is and the forecasts suggest not very. How some runs earlier had the southeast warm and the plains cold and now you have the opposite doesn't inspire much confidence. Agreed. I'm a weather prediction guy, so this stuff is a little bit out of my element. It makes sense to me (after looking at the variability in the day-to-day plots) why they do time-lagged ensembles and put out monthly and tri-monthly products (though I'm sure volume/dataflow play into it too). Link to comment Share on other sites More sharing options...
BethesdaWX Posted January 24, 2012 Share Posted January 24, 2012 MJO forecast to extend well out into octant 6, the 6 - to - 8 progression is a good one for us. Trend has been "up and out" over the past several days, though skill is minute with the GEFS, the timing fits in? Link to comment Share on other sites More sharing options...
easternsnowman Posted January 24, 2012 Share Posted January 24, 2012 Weeklies = torch. temps fall back to just on the + side of normal by week four... but that's week four. The same weeklies had record warmth for this week. Link to comment Share on other sites More sharing options...
usedtobe Posted January 24, 2012 Author Share Posted January 24, 2012 Weeklies = torch. temps fall back to just on the + side of normal by week four... but that's week four. The cfs2 also is back to being warmer again and looking pretty nina-ish. The bouncing around isn't good for confidence in a feb guess. It probably will change some next run. Link to comment Share on other sites More sharing options...
Ellinwood Posted January 24, 2012 Share Posted January 24, 2012 The cfs2 also is back to being warmer again and looking pretty nina-ish. The bouncing around isn't good for confidence in a feb guess. It probably will change some next run. That's a lot more Nina-ish than what the Euro weeklies have, which is more along the lines of persistence through the first half of the month (though the Nina signal starts to show up around mid-month on the week four map). Link to comment Share on other sites More sharing options...
dtk Posted January 24, 2012 Share Posted January 24, 2012 The cfs2 also is back to being warmer again and looking pretty nina-ish. The bouncing around isn't good for confidence in a feb guess. It probably will change some next run. Wes, that's from the older ensemble (ICs from late December). Here is the updated map from the ICs within the past 10 days (still warm). Link to comment Share on other sites More sharing options...
usedtobe Posted January 24, 2012 Author Share Posted January 24, 2012 Wes, that's from the older ensemble (ICs from late December). Here is the updated map from the ICs within the past 10 days (still warm). Where did you get that from? I tried your links earlier and got error messaes. The same holds for the HPC and PC sites. That that the look of a positive EPO and neutral to positive AO. I'd be interested in seeing the height anomalies associated with it. Link to comment Share on other sites More sharing options...
dtk Posted January 24, 2012 Share Posted January 24, 2012 Where did you get that from? I tried your links earlier and got error messaes. The same holds for the HPC and PC sites. That that the look of a positive EPO and neutral to positive AO. I'd be interested in seeing the height anomalies associated with it. Hmm, this is from Wanqui's page: http://origin.cpc.nc...wang/cfsv2fcst/ Which is linked from the main CFS page: http://cfs.ncep.noaa.gov/ The image I linked is from the E3 (latest ensemble) under the US T2m subset (the figure you posted should work if you click on the E1 in the same row, since it's from the oldest time lagged ensemble subset). Unfortunately, they are only generating height anomalies for 200 hPa on that page. Link to comment Share on other sites More sharing options...
usedtobe Posted January 24, 2012 Author Share Posted January 24, 2012 Hmm, this is from Wanqui's page: http://origin.cpc.nc...wang/cfsv2fcst/ Which is linked from the main CFS page: http://cfs.ncep.noaa.gov/ The image I linked is from the E3 (latest ensemble) under the US T2m subset (the figure you posted should work if you click on the E1 in the same row, since it's from the oldest time lagged ensemble subset). Unfortunately, they are only generating height anomalies for 200 hPa on that page. Thanks! Link to comment Share on other sites More sharing options...
Bob Chill Posted January 24, 2012 Share Posted January 24, 2012 12z GFS now basically drops a favorable pna. It shows a pretty boring zonal look full of pac air to kick off Feb. Still a ways to go but some of the recent promise in the models is less promising now. Link to comment Share on other sites More sharing options...
usedtobe Posted January 24, 2012 Author Share Posted January 24, 2012 12z GFS now basically drops a favorable pna. It shows a pretty boring zonal look full of pac air to kick off Feb. Still a ways to go but some of the recent promise in the models is less promising now. I notice that, I'm not sure it mean much as we already new the pattern was not very predictable. I'm vacilating on my feb call. Link to comment Share on other sites More sharing options...
Bob Chill Posted January 24, 2012 Share Posted January 24, 2012 I notice that, I'm not sure it mean much as we already new the pattern was not very predictable. I'm vacilating on my feb call. Euro agrees with the general ideal of zonal flow/pac air. More amplified than the gfs but nothing interesting, cold, or wintery in these parts once we roll into Feb. I know this type of fast flow pattern is tough as heck to get a handle on past day 4 or so but the 12z runs aren't showing alot of promise. Link to comment Share on other sites More sharing options...
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