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dixon
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dixon
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PostThu Sep 15, 2022 8:37 pm 
thunderhead wrote:
The euro is slightly superior at long range. For some short range variables i would say the GFS is a bit better(especially here in the US to which the GFS has been tuned and the euro has not). A wise man looks at both. The average of these models is even better than either by itself.
All great points. Definitely seems better to look at an average of the models. I've personally had good results using the Windy app which pulls from the GFS, Euro and several others. The HRRR seems very accurate down to predicting precise cloud cover/base in remote locations. It will be interesting to see how this scenario plays out.

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BigBrunyon
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PostThu Sep 15, 2022 10:03 pm 
Most FAIL to grasp the concepts presented in these weather-related data sources!!! Cliff Muss relies heavily upon these verious weather-focused database ecosystems!!! The MAIN problem with Cliff Muss is just he doesn't update enough. I demand the expectation going forward is 3 posts per day at least!!! Bare minumum!!

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gb
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PostFri Sep 16, 2022 2:35 am 
dixon wrote:
gb wrote:
The GFS model
Does anyone put much faith into the GFS these days? The Euro has been proven superior time and again. See Cliff Muss research for further details.
I don't really care what your "no global warming dude" Muss says. As to models, the GFS was consistently best this super dry, warm summer in staying with the global warming scenario and the dominance of the Four Corners High. But in late spring/early summer, as long as it was wet, the ECMWF was most often correct in staying with the wet pattern.....until it wasn't. Which model is preferred by forecasters at any point in time is stated in the Forecast Discussion each day for which they only go out 7 days. But they also augment this look by looking at the mean of forecast ensembles. That is the current discussion regarding mid next week with the Euro predicting that latter next week will not be ridge dominant, while the GFS favors the ridge dominant forecasts. The ensemble means are split on the issue. For the current period with this weather system, forecasters based on ensembles with a wide spread, believed at the time that there was a good chance that this system (now progged for California) had a good chance of providing wetting rains for Washington. This was in the longer than forecast period. Even at that time, well beyond 7 days, the GFS and the Euro both had this current low providing significant rains for Washington; albeit not heavy rains given the track of the Low from the NW. But as we got closer to the actual forecast window, it became more obvious that this Low would track onshore somewhere in Oregon. More recently it is now set to dive south along the coast to offshore California. It was never certain that we would get heavier rains out of this, hence "possible snow with perhaps light to moderate snow in the mountains above 6-8000' ". The cold air has always been a greater certainty for this current system for Washington than the precipitation, although the precipitation is what we need. Without paying an arm and a leg, the GFS is available for a much longer prognostic period than the Euro. In any case, unless going on a trip out of state, longer term forecasts beyond 4-5 days in most scenarios are not really necessary. But when hoping to see an end to forest fires, it is good to be optimistic. Ensembles are available, but that is kind of a bridge too far for longer term forecasts unless going on long hiking/climbing trips. As long ago as 1980 I used to go look at weather maps at the Atmospheric Sciences building when contemplating, say a trip to Wyoming. In fact I would not go on such a trip unless things looked favorable in the extended. Back then for Wyoming the favored was zonal flow with heights of 576 to 582 at 500 mb. When models are consistent for an extended period, it is also possible to interpolate sometimes beyond the model period with decent odds. I did this in 2017 when I went to Colorado in late September for my nephew's wedding. The problem at that time was extensive smoke throughout the West, but longer term models were consistent in having airflow in Central to SW Colorado coming from the Arizona area which was still under the influence of the NAM. Meanwhile, everywhere north of that area in the mountains of the west there was unfavorable airflow with respect to wildfire smoke. And that is exactly how the trip played out, with good sky conditions near Crested Butte and Telluride; where we hiked after looking initially 10-12 days out. Meanwhile in Denver for the wedding the skies were hazy as forecast given wind directions. The consistency of the GFS in this very extended look made it worthwhile to drive rather than fly and to hike in SW Colorado during Aspen season. It is the consistency of longer term models that sometimes "allows" a longer look with higher than average probabilities. Other long term forecasts are CPC available, though only in very crude terms; but in the discussion the CPC longer range forecasters will talk about favored extended solutions for "Week two, Week three", etc. These are based on ensemble solutions.

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gb
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gb
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PostFri Sep 16, 2022 2:53 am 
thunderhead wrote:
And of course in the short range there are models clearly superior to both of the above. HRRR is the clear winner if you are looking at something tomorrow. UW wrf is better at local topography than the global models, by far. Alas, you dont get out more than a couple days with this crop.
Exactly, when looking at very short term, one can use either the UW model or the NAM which are often similar, but short term. I've found the NAM from Windy (very good graphics) to be the best at guessing what cloud cover and drizzle prospects will be for 1-2 day hiking plans. The NAM seems to be good in this clouds and light rain scenario. The GFS and Euro are more "broadbrush". Yesterday in the Soleduck, the NAM showed some sun early, and becoming mostly cloudy between 12 and 1. It also showed some chance of light rain in the late PM. That is exactly how it played out yesterday. I got the sun, the clouds, and even light rain around 4 PM. Because of the NAM, I caught the very early first ferry. For actual precip amounts, the UW WRF can often be quite good in shorter time frames, even down to the hour of the beginning of precipitation.

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Jordan
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PostFri Sep 23, 2022 7:50 am 
I guess they can't predict weather a week out. Who knew? Oh ya, that one guy did.

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gb
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gb
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PostFri Sep 23, 2022 11:46 am 
Jordan wrote:
I guess they can't predict weather a week out. Who knew? Oh ya, that one guy did.
Are you privy to knowing what "possible" means. You would have to use a dictionary, I'd guess, there, Jr.
Quote:
When models are consistent for an extended period, it is also possible to interpolate sometimes beyond the model period with decent odds. I did this in 2017 when I went to Colorado in late September for my nephew's wedding. The problem at that time was extensive smoke throughout the West, but longer term models were consistent in having airflow in Central to SW Colorado coming from the Arizona area which was still under the influence of the NAM. Meanwhile, everywhere north of that area in the mountains of the west there was unfavorable airflow with respect to wildfire smoke. And that is exactly how the trip played out, with good sky conditions near Crested Butte and Telluride; where we hiked after looking initially 10-12 days out. Meanwhile in Denver for the wedding the skies were hazy as forecast given wind directions. The consistency of the GFS in this very extended look made it worthwhile to drive rather than fly and to hike in SW Colorado during Aspen season. It is the consistency of longer term models that sometimes "allows" a longer look with higher than average probabilities.

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