As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT ABOUT FL300 WE NOTICED A CRACKED ON CAPTAIN SIDE FORWARD WINDSHIELD. THE CRACK STARTED GROWING AND BEGAN TO ARC. THE ENTIRE PANEL SHATTERED INTACT AFTER ABOUT 30 SECONDS AFTER INITIAL DISCOVERY. GROUNDED - YES. AIR TURNBACK - REMOVED AND REPLACED CAPT'S #1 WINDSHEILD PER B737-900 AMM 56-11-11/401. PERFORMED WINDOW L1 HEAT SYSTEM TEST, OPS TEST SUCCESSFUL, REF AMM 30-41-00. LEAK CHECK GOOD.