|I'm just going to assume you've already tried the standard approaches. Namely just making the array global, or making the array static.|
You might be in luck; Excel is kind of like a huge 2D array. You could try to create a sheet, and store the relevant data there.
If not, you might need to create a file to store the data, then load that file into the array.
Since you're talking about debugging, I'll assume this isn't an issue in production. If that's the case, you might try using a smaller sample. A sample that only takes a minute or less to process.
If it is an issue in production, you might need to look into another language; say C or C++.