Iran's western airspace faced a sudden partial closure to all flights through at least November 17 amid fresh reports of possible U.S. military action, issued via NOTAM by Iranian civil aviation authorities on November 14. This step follows a fragile April ceasefire after the February 2026 U.S.-Israel strikes and Iranian retaliations that initially shut the full Tehran FIR. Ongoing GPS jamming, EASA conflict-zone advisories set for review November 16, and limited U.S. strikes on Iranian air defenses near the Strait of Hormuz continue to signal elevated risk of escalation. Traders assess full nationwide closure probabilities against these military posture signals, diplomatic statements, and any further NOTAM expansions or de-escalation moves in the coming days.