2020 Hurricane Season

Those are the ensembles. Afaik they are several runs of the same models with something changed slightly. The line in the middle is the ensemble mean with the official model being on the right side on that chart. Concerning to say the least.

Edit: This is from a weather forum where i get most of the info i post. a pro met explains...

Re: ATL: LAURA - Models
#3226 Postby ColdMiser123 » Mon Aug 24, 2020 2:11 pm

dantonlsu wrote:Can someone explain the difference between an ensemble run & operational run?


An operational run is a high resolution model forecast that uses the best estimates for starting conditions.

Ensembles are lower resolution forecasts of the same model with slightly different starting conditions, since observations of the atmosphere are never going to be perfect and have some uncertainty.

This gives us a spread of forecast possibilities with the ensembles.
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Better figure from ECMWF website. Solid line is the ECMWF Model. Dashed is the mean of their ensemble spaghetti plots.

 

Really thin.

 

The "big" update this afternoon (after they have most of the day's later model runs) just was posted on NOAA. It jogs it even a little further East. A big chunk of Houston is "technically" out of the cone in the latest run, but as people will tell you, it is still way to early to breathe too easily.

 

I don't know how good this groups forecasts are but they are sticking to their guns on a Galveston landfall...

 

Looks like he's betting on the ECMWF's spaghetti plot than on instrument measurement being highly accurate.

 

NHC or BAMWX? Yeah, the cone is shrinking. I'll roll with the NHC. Please?

I just went to HEB and it was a typical slow Monday evening. A couple of people getting water, otherwise nada. I hope most are already hurricane prepared as the season is just starting.

 

I was at Costco this morning for regular shopping and the lines were enormous. Carts full of water bottles.

 

"Houston coast"...The Euro has at least moved to the east side of Houston.

 

Yeah, slight shift west on the euro. Hooking right at the end.

 

https://www.ssd.noaa.gov/PS/TROP/CI-chart.html

.......CI......... MWS.........MWS........ MSLP...........MSLP.........Saffir-Simpson...
Number....(Knots)........(MPH)......(Atlantic)....(NW Pacific)..... Category
1................25 KTS ......29 MPH.............................................(Approximate)
1.5.............25 KTS.......29 MPH
2................30 KTS........35 MPH....1009 mb....1000 mb
2.5.............35 KTS........40 MPH....1005 mb......997 mb
3............... 45 KTS........52 MPH....1000 mb......991 mb
3.5.............55 KTS........63 MPH......994 mb......984 mb
4............... 65 KTS........75 MPH......987 mb...... 976 mb............1 (64-83 KTS)
4.5.............77 KTS........89 MPH......979 mb...... 966 mb ...........1 (64-83 KTS); 2 (84-96 KTS)
5................90 KTS......104 MPH......970 mb.......954 mb............2 (84-96 KTS); 3 (97-113 KTS)
5.5...........102 KTS .....117 MPH......960 mb.......941 mb............3 (97-113 KTS)
6..............115 KTS......132 MPH......948 mb.......927 mb............4 (114-135 KTS)
6.5...........127 KTS......146 MPH......935 mb.......914 mb............4 (114-135 KTS)
7..............140 KTS......161 MPH......921 mb.......898 mb............5 (136+ KTS)
7.5...........155 KTS......178 MPH......906 mb.......879 mb............5 (136+ KTS)
8..............170 KTS......196 MPH......890 mb.......858 mb............5 (136+ KTS)


CI -- Current Intensity
MWS -- Mean Wind Speed
MSLP -- Mean Sea Level Atmospheric Pressure in Millibars

 

This dude DT is our go to guru here in Virginia. He does a good job, with his forecasting. He is a big believer in in the European hurricane models and he explains why. Here is his video update on Laura. I already sent my folks a text message this evening giving them a heads up to start getting ready. If you are in the Houston area, I would start getting ready.

 

Ensemble mean and ECMWF main forecast now both looking closer to Beaumont.