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Several problems here, so here goes:
1) This "spaghetti plot" leverages model data and represents the track of #Dorian over time. Some models (the GFS/America and European/ECMWF) have ensembles or numerous iterations of the model with different initial conditions.
1) This "spaghetti plot" leverages model data and represents the track of #Dorian over time. Some models (the GFS/America and European/ECMWF) have ensembles or numerous iterations of the model with different initial conditions.
2) The line with shapes are true operational "models", the lines without shapes are ensembles of the American/GFS and European/ECMWF model. Notice no operational model goes through Alabama.
3) Ensembles are supposed to be noisy because they have different initial conditions.
3) Ensembles are supposed to be noisy because they have different initial conditions.
4) Notice the American/GFS and European/ECMWF ensemble mean (APxx and EExx) tracks don't go through Alabama. When meteorologists review ensembles, 95%+ of their time with them involves reviewing the ensemble mean.
5) "Almost all models" going through Alabama is inaccurate and misleading. There are more ensemble iterations/members than operational models. Secondly, if that statement were true that it is highly likely the ensemble means would go into and through Alabama. It doesn't.
6) This is a snapshot for recent model runs at a given time. Each model's output changes over time, and these models update 2 to 4 times each day. Meteorologists (including NHC) must account for this and review other data, not blindly follow a map like this.
7) The public should really never review guidance like this (see disclaimer in the graphic), and the President should NEVER be using spaghetti plots and ensemble forecasts to make decisions. Presidents get NHC forecasts and their questions answered.
8) A President shouldn't and 99.9999%+ likely doesn't know what a spaghetti plot or ensemble forecast is. This is surely a case of "someone told me about this map and it supports my augment." Meteorologists sometimes play this game, too, unfortunately.
9) Half of the GFS' ensembles are pure trash to begin with.
10) Storms are not points, and it's highly likely a land-falling hurricane in eastern Florida is a hurricane by the time it gets to Alabama.
11) Never thought I'd see a President tweet about ensembles.
10) Storms are not points, and it's highly likely a land-falling hurricane in eastern Florida is a hurricane by the time it gets to Alabama.
11) Never thought I'd see a President tweet about ensembles.
12) In summary, there is absolutely no way a President of the United States would review a map like this in advance of a hurricane. It was never going to Alabama. Trump would still make a good meteorologist because personality is king.
