Step 1: Count the days between the two dates.
From June 2 to June 30 is \(30-2=28\) days, and then from June 30 to July 3 is \(3\) more days, so the total gap is \(28+3=31\) days.
Step 2: Convert the day gap into full weeks and a remainder.
Divide \(31\) by \(7\): \(31 = 4\times 7 + 3\), so \(31\) days is exactly four full weeks plus \(3\) extra days. Four full weeks bring the day of the week back to Thursday.
Step 3: Step forward by the remainder.
Starting from Thursday and moving \(3\) days forward: Thursday to Friday is \(1\), Friday to Saturday is \(2\), Saturday to Sunday is \(3\).
Final Answer:
Three days after Thursday lands on Sunday, so July 3 falls on a Sunday.
\[ \boxed{\text{Sunday}} \]