weatherwiz

I just stick with NAM, GFS, and Euro...otherwise it just gets too complex and confusing. Anyways in the case of this upcoming weekend's event I'm just really focusing on how the models are handling the potential evolution of the pattern. With all these shortwaves, shortwave troughs, and pieces of energy involved we're going to get a million different sfc projections between now and the end of the week and they're all really meaningless anyways...unless of course we start getting a better handle on just what s/w or two will be the main focus. Given this seems largely phase dependent we could see the next 10 solutions show all snow, rain, fish storm, cutter...wouldn't really matter

There are way too many computer forecast models out there. It's nearly impossible to analyze each and every one...at least to the degree which is needed to construct the most accurate/logical forecast you can make. Just too much data/information to consume.

95 days to go!!! Will be doing a countdown post every Monday morning. Will also be incorporating one or two or five posts per week dedicated to a previous convective event.

Is this legal to post? At least they agree on the idea of ridge/trough

I was actually going to get into that in my post...was reading a bit about that on a MedEd module a bit back. I think this explains (partly) the famous D10 "fantasy" storms that arise.

I do have some fear for amped solutions. Makes me a little nervous seeing where the Euro/GFS sharpen the trough and how both advertise a rather significant MLJ streak rounding the base of the trough and where this occurs. Really too far out to be overly concerned about but is this can happen just a tad later our chances increase a bit

I think they make sense for short-range (inside 96-hours) but not outside that. it just really adds further confusing instead of clarification. That's an excellent point. I think in the perfect world, the thought that higher resolution with more data inputs would result in far more accurate forecasts, however, that doesn't necessarily seem to be the case. With how complicated and complex the atmosphere in incorporating more variables just results in a more complex and highly variable results. Even in the short-term we've seen some drastic changes...especially with larger-scale features.

that might be congrats PA but seriously...and not just with this system but just overall...there have been times of enormous differences between the two. I totally understand the time frame we're dealing with but with technology and modeling supposedly becoming better diversions just keep getting worse. Perhaps they need to start canning some models, get rid of running them 4x per day and re-prioritize the focus in improving them.

Staggering differences between Euro/GFS...almost laughable really.

Then the stupid snow maps came along. There are people who will post total snowfall through 384-HR TO ILLUSTRATE WHAT TYPE OF PATTERN MAY BE....WTF????????

the euro actually has been pretty consistent with those little pockets of CAPE moving overhead

We should also watch the June - September timeframe for a potential cold front that could spark t'storms

expansion coming tonight

Beautiful out.

@HoarfrostHubb change title to reflect convection please

GOOD CALL!!!!!!!!!!!!!1

Placement of the warmest temperatures anomalies I think worked in our favor significantly as well: also the core of the westerlies surrounding the SPV were displaced towards the other side of the hemisphere But I think I am a little confused about something...this event in 2015 (since i don't remember off the top of my head is that referring to a strong PV or weakened PV? Based on what you posted and what i did I would assume the PV is pretty strong here (2015)...which is a good thing that it is displaced towards the other side of the globe. A strong PV displaced south into Canada would result in strong westerlies over the U.S.

I wish we could poke that ridging a bit more into the GoA...even with the crappy polar region perhaps that could displace some of the cold that's been in AK our way and at least we would have that nearby. That look isn't great...but would certainly take chances given the time of year

was it east-based? I thought the east-based events had the + height anomalies positioned east of Greenland which yielded a higher likelihood for -height anomalies across the east...while a west-based had the +height anomalies so far west (and during strong events) they even were displaced south and penetrated into our region? I may have this reversed though...trying to picture in my head

We can get away with having a crappy PAC I think...although depending on what you're expectations are. If you're expecting a pattern that is going to consistently deliver well that's difficult with a crappy PAC but if we can get a favorable polar domain and get an active storm track...chances are something will deliver...perhaps more ratters than not but I'll take the chances

Yeah I certainly agree there is definitely more to it than that. The biggest weight overall I think is structure and placement of these anomalies and synoptic features. This is that extra piece which makes the seasonal forecasting challenging...sure we can have an idea of how NAO/AO may evolve based on QBO projection and how the stratosphere may evolve but we really don't know how they will be structured...and that's the key piece...I think anyways. Do you remember way back I think his name was Allan (Raleighwx) did something with breaking the NAO into regions (similar to ENSO) with east-based and west-based +/- NAO events...he even had an index to measure it...but never heard of anything since and there is very little about this online. but doing the correlations to patterns by breaking down (say a negative NAO) between east/west based increased the correlation significantly.

This is a great site with stratosphere products stratobserve.com You can see that the PV does look to elongate by around 228-hr...but then towards the end of the run it becomes more compact..I would assume though we would want it to become more displaced on our side of the hemisphere I'm glad I have that notion correct about the PV taking hits. One thing noticeable too (wish I could do this in animation) but around 228-hr there is a reversal of the zonal winds aloft...they become westerly Quite a bit of heat flux too Again though...seems like all of this is happening on the wrong side of the globe? (Of course this is based off the GFS)

I agree...but I think we're talking about different aspects here...you're referring to long-term forecasting where I'm talking about medium-range signals. The PV has been quite strong all winter...and while perhaps from an evaluation of pre-season indicators you could assume weakening based on several factors (such as descending QBO as you mentioned)...we can also see models in the 10-15 day period just start to weaken the PV and then all of a sudden inside of D10 or D8 that signal vanishes...once it becomes apparent that there indeed be direct impacts on the PV the initial forecasts really mean nothing. My understanding is that one way to weaken it is to keep pelting it with Rossby wave after Rossby wave...and strong Rossby waves. Let's say you have a 4-5 week stretch of horrific winter weather...and you think it may never end...if there is a constant flux of Rossby waves pelting the PV...that can give you a very strong indication that within the next 3-4 weeks big changes will result. Anyways...perhaps through pre-season guidance you can put a wager on these changes happening...but until you actually spot those potential developments within guidance the preseason guidance doesn't hold a whole heck of alot of merit.