The Ugrib Service

Introduction

Obtaining GRIB files using email services, as with SailDocs, GMN or MailASail is efficient insofar as a great deal of information is contained in a small email attachment. This makes it suitable for use over mobile phones and, especially, using HF or HAM radio for email.  The downside is that the user has to send an email to request the information. There are pitfalls in that the request email has to be exactly formatted. Another drawback is that it is necessary to go online and collect all emails that are in your mailbox.

There are two alternatives to using email. First, there is the browser approach, such as that used by www.theyr.net  or www.theyr,tv .  This is fine when ashore but can be prohibitively costly over a mobile phone  and impossible via HF radio.

 The second alternative, although not possible without an Internet connection, is to have a program that goes direct to the data source and downloads the data virtually immediately without the penalties of using a browser and all the attendant costs involved in accessing a webpage. This method is used by some commercial services, such as  ProGRIB and Movingweather.

A free service, albeit with less data options at present, but great flexibility in operation has been developed by Ugrib.  This is one of the easiest of all systems to use.

Setting up and using

The starting point is to  download the free combined data retrieval and viewer software from http://www.grib.us/.  The download is about 2.5 mb, a little  larger than with Saildocs but much less than other services. Having run the program you then have all the necessary software on your computer.

Area selection is on-screen and is extremely easy and precise (I found it rather more so than the commercial systems). It is extremely flexible in that users can select time and grid spacing of the data from 3 to 24 hourly and 1/2 or 1 degree. At present the data available are wind, pressure and precipitation. There is on screen indication of the file size.

Very usefully, it is possible to restrict the file size  Basically, the software gives a sample of data with your selected element and time interval.   It is as flexible 

as SailDocs  and easier to use than email services  It is much more flexible than several other systems, free or commercial  The data are displayed instantly on the very clear viewer and are always saved for future use or with another viewer if required.  Requests are replied to within a very short time scale, less than a minute.

I am told that it is suitable for us with Iridium as well as GSM or GPRS telephones. 

Like several other services, it is still subject to further development and the providers will be interested to know of problems.

There is a French language version and a German one is planned.

Ugrib selection display

The Ugrib selection screen looks like this.  The area is selected by hitting the wind arrow and then dragging the pointer across the screen. The area chosen is confirmed by the numbers in the area selection boxes "Area Selection". Areas can be saved for future use. As an alternative,

you can enter  or amend the lat/lon  in the boxes.  For the area shown,
1 degree spaced data at 6 hour intervals for 5 days, the download will be 21 kB. Selecting "Limit file size" allows the user to define the maximum download. This is an important feature when using cell or satellite phone.

After hitting "Download Grib File", you are told to wait, a message appears at the bottom of the screen saying that files have been downloaded to the folder of your choice. The file will then open automatically in the viewer as shown here. The blue areas are areas of rain. These will show as areas of organised