Storm log › 2026-10-21

G1 storm watch: October 21, 2026

An automatically generated record of NOAA geomagnetic storm activity for 2026-10-21 (UTC date). Last updated Wed Oct 21, 2:55 PM ET.

Date (UTC)	2026-10-21
Highest Kp so far	4.00
Storm level observed	below G1
NOAA watch for this date	G1

What happened

NOAA issued a watch for G1 (minor) conditions on this date (UTC). The highest Kp observed or estimated so far is 4.00, so storm level had not been reached when this was last updated.

watch NOAA's geomagnetic storm watch gives the highest level expected by day (UTC): Oct 21: G1 (minor); Oct 22: below G1; Oct 23: below G1. Issued Tue Oct 20, 3:12 PM ET (2026-10-20 19:12 UTC). NOAA headline: “WATCH: Geomagnetic Storm Category G1 Predicted” · SWPC alerts

Our summaries of NOAA SWPC products (U.S. government work, public domain); headlines quoted from NOAA.

What it means for US viewers

Minor storm level (G1) possible: an outside chance along the northern US border

At Kp 5, aurora is mainly a high-latitude event (Alaska, Canada). Our guide's rough rule is that the northern edge of the contiguous US usually needs Kp 6–7, so at Kp 5 a sighting there is an outside chance at best, low on the northern horizon from a very dark site.

Based on the storm level above, using the rough latitude bands in our Kp index guide.

When to look

For this date, the best chances in the US are after dark on the evening of 2026-10-21 and through that night.

Look after full darkness, especially within an hour or two of local midnight, roughly 10 p.m. to 2 a.m. local time; strong storms can widen that window. In interior Alaska in winter, UAF suggests about 9 p.m. to 3 a.m. Face north, get away from city lights, and give your eyes 15–20 minutes to adapt. A phone camera on a long exposure often shows aurora that looks faint or grey to the eye.

Forecasts are uncertain. Kp forecasts are often wrong about timing and strength. Storms can arrive early, late, weaker or stronger than predicted, and short bursts (substorms) are not captured by a 3-hour average. Even with strong activity you need clear, dark skies: clouds, city lights and a bright moon can hide the aurora completely. This verdict is generated automatically from NOAA data using fixed rules, and is general information only. It is not an official forecast and not for safety or operational decisions. NOAA SWPC is the official U.S. source: see its 30-minute aurora forecast and 3-day forecast.

Right now

This post is a record and may be out of date. For the current outlook see Aurora tonight. Background: Kp index guide · Best US places and times · How to see the northern lights in the US.