A Boeing 737 First Officer reported a cockpit window heat element failure; resulting in a cracked outer pane; which necessitated an immediate descent and continuation to the destination airport at a reduced altitude.

Narrative

We had just completed a cruise descent from FL340 to FL280. Just as we were reaching FL280 I noticed a strange sound and looked to the Captains L1 window to see that there was a glowing coming from the window heating element followed by a subsequent cracking sound and the outer pane of the window cracking. Having both noticed this; the Captain and myself put on our shoulder harnesses; the Captain elected to turn off the window heats for the respective window; [requested priority handling]; and begin a descent to 10;000 feet. ATC was notified and we began a descent. During the descent the Captain took the aircraft and radios while I ran the QRH procedure for the condition WINDOW DAMAGE-FORWARD. Flight Attendants were made aware of the situation and a PA was made to the passengers advising them of the possibility of fire trucks being present when we land. Dispatch was also kept in the loop and concurred with our decision to continue to our intended destination of ZZZ. The flight continued and landed without incident.