Space weather today in San Diego, CA

Space weather in San Diego today

G1 minor geomagnetic storm forecast (NOAA, 2026-11-06 01:54 UTC). The planetary Kp index is 2.3 now and forecast to peak at Kp 5 in the next 24 hours. NOAA gives a 35% chance of R1–R2 radio blackouts today, 10% for R3 or stronger, and 5% for a solar radiation storm.

Radio: solar flares only black out HF radio on the half of Earth facing the Sun. The Sun is 15° below the horizon in San Diego now (6:02 pm local time). The biggest flare in the past 24 hours was M3.5 at 10:33 am local time, while San Diego was in daylight, so HF radio here may have faded briefly. HF radio is mainly hit by daytime solar flares (radio blackouts), not by geomagnetic storms.

GPS and power: GPS is normally unaffected; only severe G4–G5 storms cause noticeable errors here. Power grid effects are very unlikely at this latitude.

Aurora chance tonight in San Diego

Unlikely tonight (Kp 2.3 forecast; San Diego needs an extreme Kp 9 storm). At 39.0° N geomagnetic, San Diego is far from the auroral oval; only extreme Kp 9 (G5) storms such as May 2024 bring the aurora into view, mostly to cameras.

At the forecast Kp 5, the aurora's visible edge stays about 1,579 km north of San Diego.

NOAA 3-day space weather forecast

Chances that NOAA issues each level somewhere on Earth. Radio blackouts only affect the sunlit side; geomagnetic storms are global but strongest near the poles.

Strongest solar flares this week

C-class and stronger flares from the past 7 days, local time in San Diego.

• M3.5 flare peak Thu 10:33 am, R1 minor radio blackout
• C2.9 flare peak Thu 1:34 pm
• C2.5 flare peak Thu 4:24 pm
• C2.2 flare peak Wed 9:34 am
• C1.3 flare peak Thu 2:31 pm
• C1.2 flare peak Thu 2:21 pm
• C1.2 flare peak Tue 10:54 pm
• C1.1 flare peak Thu 9:00 am
• C1.1 flare peak Tue 2:39 pm
• C1.1 flare peak Sun 4:36 am

What the scales mean

Space weather is the Sun's effect on Earth. NOAA rates it on three 1–5 scales. R (radio blackouts) comes from solar flares: X-rays reach Earth in 8 minutes and disrupt HF radio on the sunlit side for minutes to hours. S (solar radiation storms) comes from energetic protons a few hours later, a hazard for satellites, polar flights and astronauts. G (geomagnetic storms) comes 1–3 days after a coronal mass ejection or a fast solar-wind stream hits the magnetic field: it drives the aurora and can upset GPS, HF radio and power grids.

The Kp index (0–9) measures geomagnetic activity in 3-hour blocks: Kp 5 is a G1 storm, Kp 6 G2, Kp 7 G3, Kp 8 G4 and Kp 9 G5. Flares are classed A, B, C, M and X by peak X-ray brightness, each class ten times the one before; M1 flares cause R1 blackouts and X1 flares R3.

Space weather for nearby cities

• Space weather Coronado
• Space weather Spring Valley, CA
• Space weather El Cajon
• Space weather Tijuana
• Space weather Escondido
• Space weather Carlsbad
• Space weather Vista
• Space weather Oceanside

More sky pages

• Space weather today (worldwide)
• Aurora forecast
• Meteor showers

Guides

• Solar Flares and Geomagnetic Storms Explained: R, S and G Scales
• What Kp Index Do You Need to See the Northern Lights?
• How to See the Northern Lights Tonight: A Practical Guide
• GPS Jamming and Spoofing Explained: How Maps Detect It