i am trying to run a precipitation model and am using the Rand()
function to help generate numbers inbetween certain values. I am also
using solver in my spreadsheets, The solver is having a hard time
calculating everything because the random numbers are being
regenerated every time. Without Copy and Special Pasteing the Value
of the generated random number, is there another way i can keep the
Rand() function from generating new numbers everytime and only when i
tell it too.

One way is to first allow circular references by checking the box:
Tools Options Calculation Iteration

Then in B1 use a formula like:
=IF($A$1="",RAND(),B1)

As long as A1 is non-empty, B1 won't change.

Caution: allowing circular references can be a risk. Later, if you make a
circular reference in the workbook by mistake, Excel won't flag it as an
error.