To use, enter as much data as you can from your own island. The tool will figure out all possible patterns and predict the lowest and highest prices for each day.

I couldn't have done this without Ninji's work extracting the code

Support, comments and contributions are available through Github

Probability
Last week’s pattern affects the probability of patterns for this week. If you know it, select it to see probabilities for this week. (optional)
Daisy Mae
Check this box if you bought from Daisy on your own island for the first time ever. If you bought from her on your own island in a previous week, leave this box unchecked.
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Your turnip prices will be one of the following patterns. Each cell contains the minimum..maximum price for that half-day. If you don't have a pattern, something's gone wrong, sorry 😓. Check back next week!
Pattern % Chance Sunday Monday Tuesday Wednesday Thursday Friday Saturday Guaranteed Minimum Potential Maximum
AM PM AM PM AM PM AM PM AM PM AM PM