Polar vortex, jet streams, blocking, teleconnections, ENSO and the atmosphere's angular momentum — measured every day against the whole record.

DATA THROUGH 2026-11-07 · UPDATED 2026-11-08 11:26 UTC

ERA5 + IFS2.5°DAILY

Briefing · 7 November 2026

El Niño, negative NAM descending, MJO phase 2

El Niño conditions: 91-day Niño 3.4 anomaly +3.0 K (relative Niño 3.4 +1.9 K).

The lower-stratospheric NAM is negative (-2.1σ at 100 hPa), which tends to project onto a negative AO in the following weeks.

MJO active in phase 2 (amplitude 2.3).

The polar vortex is weak: 2 m/s at 60°N, 10 hPa, 0th percentile for the date.

The vortex is stretched (aspect ratio 2.2, axis near 92°E/272°E), a shape linked to cold-air outbreaks at either end of the axis.

Global Wind Oscillation phase 8 at 1.4σ — High AAM beginning to fall; negative frictional torque.

Wave driving of the vortex over the past 40 days is high (100-hPa heat flux, 99th percentile for the date), which tends to precede a weaker vortex.

The Atlantic eddy-driven jet sits north of normal (68°N, 100th percentile).

North America weather regime: Pacific Trough (8 days, NA4).

Atlantic–Europe weather regime: Atlantic Ridge (6 days, EUR7).

The North Pacific jet is in its poleward shift regime.

The mid-latitude flow is unusually wavy (500-hPa sinuosity 91st percentile).

QBO westerly at 50 hPa (+11 m/s, westerly since 7 Aug 2026; +13 m/s at 30 hPa on 1 Nov 2026).

Positive Indian Ocean Dipole (DMI +0.7 K).