GRIB Files: Getting them and Reading them

[Tspringer]

Anyone have experience with this? I am looking for the cheapest and simplest means of accessing, downloading and then reading GRIB files as a tool to forecast the weather.

Ideally, i would like for the files I need to be emailed to me so I can download via Sat or cell phone, then move to the PC and there use some software to read and interpret them.



Terry

[Steve Pope]

Grib files?? what are they, and where from??

[dacust]

Tspringer:

Try google search:

grib e-mail - Google Search

grib viewer - Google Search

Too many links to list...

Steve Pope:

Try wikipedia
GRIB - Wikipedia, the free encyclopedia

[Steve Pope]

Yeah, I should take my own advice, that is what I suggest to other posters.

[Delezynski]

Simple,

Get your HAM ticket or pay for a SailMail account, A computer and Pactor modem.

In the program (Airmail) thaat runs the pactor modem is a catalog of files you can download. Just select the area you want and the GRIB will be sent to you the next time you log in.

Greg

[dacust]

Originally Posted by Steve Pope

Yeah, I should take my own advice, that is what I suggest to other posters.

LOL

-dan

[Nauticatarcher]

You dont need sailmail account to use Saildocs email service or Globalmarinenet Grib service as they are automated email services that just bounce back requested file to email address that requested it

[Paul Elliott]

I put up on my website a description of how I do this, including getting grib files and other weather info via Iridium satphone -- a combination of Saildocs and Global Marine Networks "Xgate". I haven't written a step-by-step "how-to", but there should be enough information and links to get you started:
VALIS

I'm not promoting my website or anything, but several people had asked me for a description so I decided to write it down.

[waterworldly]

Great web site Paul! Lots of good info. YOU SHOULD PROMOTE IT, you have done a great job of describing your "Stuff". Thanks for that.

[Hud3]

If you want to see what a GRIB file looks like, send an email message to Home Page with anything you want in the subject line. In the body of the email, type

gfs:10N,50N,40W,120W

This will return a 24/48/72 hour forecast GRIB file with wind and pressure data within the rectangle represented by the Lat/Lon limits. You can change the corners of the rectangle to suit your location. Use the little pull-down at the top to change the forecast time.

Airmail has a weatherfax/GRIB viewer, free download, here:
Airmail weather fax

GRIBs are raw model output from large scale computer models. They are useful in conjunction with other interpretive weather forecasts, but need to be used with care. Saildocs includes the following note with the GRIB...

"Notes & WARNINGS:

This grib file is extracted from a computer forecast model. While such computer data can provide useful guidance for general wind flow, there are limitations which must be understood. What you are receiving is a weather prediction generated by a computer run by NOAA/NCEP (GFS, WW3 models) or the US Navy (comaps, nogaps) and downloaded and processed by Saildocs (a service of Sailmail). The network is complex, and any computer network is subject to hardware and software failures or human error which can effect accuracy or availability of data. In particular, if our servers were not able to download a current data file then the grib-file may be based on old data. The file information is shown above and also contained in the file itself.
Also remember that grib data is not reviewed by forecasters before being made available. You are getting a small part of the raw model data that the forecasters themselves use when writing a forecast, and it is your responsibility to make sure that the data is consistent with your local conditions and with the professionally-generated forecasts (e.g. text bulletins and weather-fax charts).
Grib data also has limitations along shore, where local effects often dominate and may not be adequately modeled. In addition these models cannot provide adequate prediction for tropical systems, frontal activity or convergence zones. For example, while global models can provide useful data on the likely track of hurricanes, they grossly underestimate the strength of hurricanes because of their small size compared to the model grid. For hurricane/cyclone forecasts, carefully monitor the appropriate warning messages and do not rely on grib data from any source.
That all said, grib data can provide useful guidance not available elsewhere. Understand the limitations and use the data carefully. Grib data should be considered supplemental to other forecasts, and not be relied upon in lieu of professionally-generated charts or forecasts."

[camaraderie]

There was a boat that went down in a storm off NC last year that the captain said "had a good grib forecast." They should ONLY be used as supplementary data to a REAL forecast. A good reminder HUD.

[TritonSailor]

I know this thread was put to sleep a long time ago, but I had an answer to the thread starters question, so here it is:

GRIB.US > Home

Regards,

Jeff

[barnakiel]

Grib.us is OK but does not deliver via e-mail.

Franksingleton's site explains clearly how to get gribs via e-mail:

Franks-Weather / Frank Singleton's Weather and Sailing Pages | The Weather Window

Then you can view them with most of today's software (we use the MaxSea as we like its overlay of the weather on nautical charts, and the fact that weather routing can be done within the same software).

b.

[Ruzanna]

Originally Posted by Tspringer

Anyone have experience with this? I am looking for the cheapest and simplest means of accessing, downloading and then reading GRIB files as a tool to forecast the weather.

Ideally, i would like for the files I need to be emailed to me so I can download via Sat or cell phone, then move to the PC and there use some software to read and interpret them.



Terry

Dear Cruisers' Forum, I am new to your community. I came across with your site while looking for assistance on how to interpret GRIB files. I understand that they are not 100% accurate in forecasting weather. However, I need your help. We use SkyEye grib reader soft. Could somebody explain the parameters that those charts provide - arrows with multiple ends, their colors, etc. ? With appreciation.

[Paul Elliott]

Originally Posted by Ruzanna

Dear Cruisers' Forum, I am new to your community. I came across with your site while looking for assistance on how to interpret GRIB files. I understand that they are not 100% accurate in forecasting weather. However, I need your help. We use SkyEye grib reader soft. Could somebody explain the parameters that those charts provide - arrows with multiple ends, their colors, etc. ? With appreciation.

The wind arrows are commonly used in forecast and analysis charts. Here is a website that describes the typical symbols used: Surface Weather Analysis Chart This site shows other symbols (cold fronts, etc. that you won't see on the grib chart), but the arrows are described well. The short answer is that the arrow points in the direction the wind is blowing, and the feathers (barbs) indicate the windspeed. A short barb is five knots, a long barb is ten, and a triangular barb is fifty knots (we don't like those). Just add up the barbs to get the wind strength.

As for the colors, these aren't standardized, and some display programs (yours perhaps) will let you customize the colors. They are probably showing surface pressure contours, or perhaps wave heights. There should be a helpfile or similar.