If you intend to run multiple programs at once then you definitely need to pump that thing up in RAM to the max it can hold. Processor wise, that thing is way overqualified to be used merely to open a dozen+ browser windows (heck a pentium 2 will handle that easily).
You need to check what software you will be running when you go storm chasing. You know, not programs found in windows or that you buy at the store... the programs that you need to use 'on the job' usually given to you by the job. Unless they're really hard core scientific software packages, I don't see that CPU having any problem running them plus multiple browser windows.
So... pump RAM to max and also make damn sure that the battery power will last you enough (or get yourself 2 extra batteries). I've done on-the-field stuff and the worst thing you can have is the damn battery running out and having no backups. A car charger would also be a must.
For internet, get yourself those new wifi 3g cards like the MiFi 2000 from Virgin Mobile (verizon also has a similar one).
http://www.virginmobileusa.com/mobile-broadband/mifi-2200.htmlin a nutshell its a credit card sized wireless router that connects itself to the internet via 3G and gives wireless internet up to 5 devices around it. Excellent little tool and for 40 bucks a month unlimited data @ 4mbit its a steal.
