How it works

SolarStormAlert pulls directly from the public instruments and agencies that monitor the Sun and near-Earth space, checks their freshness, and shows you the best current picture — with every number traced back to its source.

Our sources

We poll these public feeds around the clock:

• NOAA SWPC · Kp index & storm alerts · polled every 15 minutes
• NASA GOES · X-ray flux & proton flux · polled every 15 minutes
• ACE/DSCOVR (at L1) · solar wind · polled every 2 minutes
• NASA DONKI · coronal mass ejections (CMEs) · polled hourly

Want more detail on where this data comes from and how the sources differ? See the data sources in depth →

Our method

Each panel on the dashboard shows the most recent reading from its source, tagged with a citation pill: where the number came from, how old it is, and how often it refreshes. When a source is unavailable, we say so — we don't fill the gap with a stale or guessed value. This held during a real NASA DONKI outage: the CME panel correctly showed "unavailable" rather than a false healthy reading.

Want to see this for yourself? Check current source status →

The G / R / S scales

NOAA rates space-weather severity on three independent 1-to-5 scales:

• G — Geomagnetic storms: disturbances in Earth's magnetic field that can affect power grids and satellite operations. G1 is minor, G5 is extreme.
• R — Radio blackouts: caused by solar X-ray flares; degrade or block high-frequency radio and GPS signals. R1 is minor, R5 is extreme.
• S — Solar radiation storms: streams of energetic particles from the Sun that can affect satellites, astronauts, and polar aviation routes. S1 is minor, S5 is extreme.

SolarStormAlert's dashboard and alerts use the G-scale as the primary at-a-glance indicator; the same three scales underpin NOAA's own official warnings.

Solar flares also get their own heads-up: when GOES X-ray flux crosses the R3 (X1.0) threshold, we send a source-cited notice — via NOAA GOES / SWPC's R-scale — for a radio-blackout (HF) signal only. It's tracked separately from the G-scale, since a strong flare does not by itself mean a geomagnetic storm is coming.

SolarStormAlert also relays NOAA SWPC's own geomagnetic sudden-impulse warning when NOAA issues one — a weaker, official-relay signal than our own-instrument shock warning. It means NOAA has flagged a sudden impulse in the solar wind that did not meet — and does not change — the threshold our own instruments use to declare a shock; whether a significant geomagnetic storm follows is separate and not yet known.

SolarStormAlert also sends a heads-up when NOAA sharply revises its own three-day Kp forecast upward for a future window — via NOAA SWPC's 3-day Kp forecast. A revision counts as sharp when the forecast for that window crosses a full G-scale band higher than an earlier forecast said (for example, a window that read below G1 is later revised to G1), never a small shift in the underlying Kp number alone. This is a distinct signal from our forecast-severity heads-up: that one says the forecast is now severe (G4 or G5); this revision heads-up says the forecast just got worse, for changes that stay below that severe threshold. The two never fire for the same forecast change.

What you can receive

The dashboard is free, with no account required. If you want to be notified, you can subscribe to email alerts at a G-scale floor you choose — G3, G4, or G5 — with double-opt-in confirmation, one-click unsubscribe, and a test alert so you know it works. Alerts cover the full early-warning path: an early heads-up when forecast conditions start building, a firmer warning if our own data confirms it, and a confirmed alert once the event is observed — plain language throughout, no internal jargon. You'll also receive the R3 (X1.0) flare heads-up described above regardless of your chosen G-scale floor, since it reports a separate radio-blackout signal, not a geomagnetic one. If NOAA issues its own sudden-impulse warning, you'll receive that too, regardless of your floor — a weaker, official-relay signal than our own-instrument shock warning, not a geomagnetic storm confirmation. If NOAA sharply revises its own forecast upward for a future window, you'll receive that heads-up too, regardless of your floor — it reports the forecast trajectory getting worse, not a confirmed severe forecast. Once subscribed, a magic link lets you view or change your subscription from any device, no password required. Mobile push notifications are planned for a future release.

What we won't do

No spam: each distinct official warning is sent at most once — no repeated nagging about the same event, and no stream of updates. During a significant storm you may receive a few genuinely separate alerts (for example, a sudden-impulse relay and a distinct geomagnetic storm watch), but never more than one for the same warning. No pressure, no urgency language designed to make you act. Your email address is used for alerts only. You can export or delete your data at any time — see our privacy policy.