• Stormtrack's forum runs on Xenforo forum software, which will be undergoing a major update the evening of Wednesday, Feb 28th. The site may be down for a period while that update takes place.

How you, too, can look at high res Level 2 historical radar

I thought I'd post this quick step-through on how anyone can, using free data and trialware software, review historical Level 2 (higher resolution, all tilts) radar data. Many of the posters on this board already know about this tool and the free data it can read, but I only recently discovered it, which leads me to believe that others may yet to have hear of it.

First, you will need to fetch the program "GRLEVEL2". This program runs on PC computers and can be found at:

http://www.grlevelx.com/

Once you have installed this program (note: it's 30 day trialware), you can then head over to:

http://hurricane.ncdc.noaa.gov/pls/plhas/H...atasetname=6500

Here you can input any radar station, any time, any day from 1995 to 24 hours ago. Select your date range (likely, you will only want to request one day; make the beginning day and the ending day the same). Once you continue, you will be presented with good ol' cryptic filenames. Essentially, all you are concerned about are the last few numbers of the filenames, which represent dates and hour ranges in zulu. Pick the file(s) that cover the range of hours you're interested in. Unless you want to untar the files yourself, be sure to click the "untar files after retrieval" option. (If you don't know what "tar" is, just click YES). Next, you will be presented with a long list of every radar data file in the given hour ranges. The files naming conventions again represent date and time, with the difference now being that each file represents an exact time/radar scan set. You can either download all the files, or you can select which times you are interested in. Once you have selected which files you're interested in, click the button to complete the transaction. You will be sent to a status screen. Depending on the amount of data you requested, your request will take anywhere from a few minutes to a Long While. If you're only grabbing a few hours of data, it should only be a few minutes' wait. You don't have to hover over this screen, however -- when the data is ready, NCDC will send you an automated email that will tell you exactly where to go to get your data. You can get it via FTP or by right-click saving at the webpage it provides.

Once it is all downloaded, I'd put the files together in a folder where you can keep track of them. To load the files in to GRLEVEL2, fire it up, click File->Open, and then select the range of files/times you want it to load. From there, it's pretty intuitive.

This is a really cool tool, and great for postmortem on chases.

When you're done, you can get images like this (from the Hallam, Nebraska storm, just before it struck Hallam) :

bref.jpg


basevel.jpg


You can even load up vertical slices of storms:

vertrefl.jpg


vertvel.jpg
 
Thank you, thank you, thank you

Thank you very much! This will be incredibly helpful!
 
Back
Top