FORECASTCONTEXT.COM · THE LARGE-SCALE STATE BEHIND THE FORECAST BRIEFINGMOTIONOUTLOOKMETHODSAPI☀ AUTO

FORECAST CONTEXT

DATA THROUGH 2026-10-12 · UPDATED 2026-10-13 11:02 UTC

ERA5 + GFS2.5°DAILY
BriefingStratospherePolar vortex
U60N_10

U 60°N 10 hPa

Zonal-mean zonal wind at 60°N, 10 hPa. Easterly (<0) in Nov–Mar marks a major sudden stratospheric warming. — Charlton & Polvani 2007