Magnetic storms tomorrow
Geomagnetic forecast for tomorrow, Saturday, June 13. Maximum Kp index, hourly outlook and expected storm level (G-class).
⚠ Magnetic storm expected — possible impacts on sensitive individuals, satellite comms and power grids.
Minor disturbance. Small power-grid fluctuations possible. Auroras visible above 60° latitude.
Hourly forecast · Saturday, June 13 (MSK)
Recommendations
- • At Kp ≥ 5, weather-sensitive individuals should reduce physical load, monitor blood pressure and stay hydrated.
- • Long-distance drivers — extra rest; GPS and radio may have interference.
- • At high latitudes with Kp ≥ 5 auroras are possible — watch after sunset away from city lights.
More about tomorrow's forecast
Forecast for tomorrow, Saturday, June 13: expected maximum planetary Kp = 5.7 — level G1. The forecast is based on the NOAA Space Weather Prediction Center 3-day bulletin, published daily at 12:30 UTC. Hourly detail covers eight 3-hour windows.
How to read a Kp forecast: values 0–4 mean a quiet or slightly disturbed magnetosphere; Kp = 5 equals G1 (minor storm); 6 = G2 (moderate); 7 = G3 (strong); 8 = G4 (severe); 9 = G5 (extreme). NOAA combines current solar-wind data from DSCOVR, recent CMEs and solar cycle activity. 1-day forecasts are ~70–80% accurate, 3-day ~50–60%.
If a G1+ storm is expected, weather-sensitive people should prepare in advance: sleep well, avoid alcohol and caffeine, take prescribed medication. Drivers should factor in extra rest — at G3+ GPS and HF radio may glitch. The By city section localises the forecast for your geomagnetic latitude and aurora chance.
When to expect the peak. Tomorrow's maximum Kp is forecast for around 09:00 MSK at Kp = 5.7. NOAA publishes the 3-day bulletin once a day at 12:30 UTC (15:30 MSK) — the next refinement will arrive in about 8 hours. Between bulletins the forecast is nudged by the 3-hour planetary-k-index feed, but the daily bulletin sets the bigger picture.
Where the magnetosphere stands right now. Current Kp = 3.0, Dst = 0 nT — the ring current is quiet, and the Kp trend over the last 6 hours is falling. This matters because reading the magnetosphere as it is now raises or lowers confidence in tomorrow's forecast.