Tonight in San Antonio: Aurora is unlikely in San Antonio right now. The sky is not dark enough yet. AuroraMe watches Kp, clouds and darkness for this location and sends a free alert when the next viewing window opens.
aurora visibility now
Unlikely
Wait for darkness
Kp now 5.3 Too low need 9+
Clouds 100% Overcast
Sky Daylight visibility
Weather data by Open-Meteo.com Licensed under CC BY 4.0. Modified by AuroraMe: location snapped to a privacy-preserving 0.25° grid and values rounded for display.
Get a 72-hour aurora forecast and free alerts for San Antonio
Forecast
Time
Kp
Visibility
08.11, Today
18:00
4.7
Unlikely
19:00
4.7
Unlikely
20:00
4.7
Unlikely
21:00
5.0
Unlikely
22:00
5.0
Unlikely
23:00
5.0
Unlikely
Kp Index: 27-Day Forecast
Predicted geomagnetic activity based on solar rotation cycle.
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aurora nights per year
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Best Months to Visit Sep, Oct, Mar, Apr
Planning a trip? Find the best month and how many nights to stay
All 12 months ranked Min nights for 80% chance Push alert 1h before aurora 72-hour forecast
Why this forecast?
Five signals decide whether you'll see aurora from San Antonio tonight. AuroraMe re-checks them every 15 minutes, and all five have to line up: even a strong storm stays invisible behind clouds or in a bright sky.
Aurora Zone
Higher magnetic latitude = better aurora visibility. Your location's magnetic latitude determines how often auroras appear overhead.
Status Levels:
Perfect Above 62.0° — Excellent aurora visibility (daily activity)
Good 56.0° - 62.0° — Good aurora visibility (regular storms)
Acceptable 50.0° - 56.0° — Fair aurora visibility (strong storms only)
Low Below 50.0° — Poor aurora visibility (extreme storms)
Aurora Zone
Low 39.0°
Kp index
Kp measures global magnetic disturbance. Higher Kp = stronger auroras visible at lower latitudes.
Status Levels:
Storm Kp 6-9 — Geomagnetic storm, strong auroras
Active Kp 3-6 — Moderate activity, good conditions
Quiet Kp 1-3 — Low activity, weak auroras
Very Quiet Kp 0-1 — Very quiet, minimal auroras
Kp index
Active 5.3
Cloud Cover Impact
Clear skies are essential for aurora viewing. Clouds block your view of the northern lights. The percentage shows cloud coverage (0% = clear skies, 100% = overcast).
Status Levels:
Clear Clear (0-25%) — Perfect for aurora viewing
Partly Cloudy Partly Cloudy (26-50%) — May partially block view
Cloudy Cloudy (51-85%) — Significantly blocks aurora
Overcast Overcast (85%+) — Blocks aurora completely
Cloud Cover Impact
Overcast 100%
Moonlight
Bright moonlight can wash out faint auroras. New moon provides the darkest skies for optimal viewing.
Status Levels:
New Moon Darkest skies — Best for faint auroras
Crescent Dim moonlight — Good for viewing
Quarter Moderate moonlight — May wash out weak auroras
Gibbous Bright moonlight — Reduces aurora visibility
Full Moon Very bright — Only strong auroras visible
Moonlight
Crescent 14%
Darkness
Darker skies are essential for aurora viewing. The sun must be below the horizon for auroras to be visible.
Status Levels:
Night Darkest conditions — Optimal for auroras
Astronomical Twilight Dark enough — Good aurora viewing
Nautical Twilight Getting darker — Weak auroras may appear
Daylight Sun is above horizon — No aurora visible
Darkness
Daylight
Aurora Borealis Viewing in San Antonio
Major city with 2M+ population.
San Antonio sits at 39.0° magnetic latitude, which means aurora typically becomes visible when the Kp index reaches 9+. Aurora sightings in San Antonio require stronger geomagnetic storms (Kp 9+), which occur a few times per year. When storms do hit, the best viewing window is 10 PM to 2 AM local time under clear, dark skies.
For the broader storm picture before checking San Antonio, start with the broader forecast hub and the geomagnetic storm tracker. Low-latitude places like San Antonio usually need a severe geomagnetic storm, clear northern horizon, and full darkness before northern lights become realistic.
Know when the sky is worth your time.
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Aurora is Rare in San Antonio — But Not Impossible
Kp 9+ needed to see aurora here
0 possible aurora nights in the next 27 days
Sep, Oct, Mar, Apr best months to visit
Other cities in United States
Austin
Texas capital with Hill Country aurora viewing during major geomagnetic storms
Unlikely
Houston
Space City with gulf coast aurora sightings during extreme solar activity
Unlikely
Fort Worth
Major city with 935K population
Unlikely
Arlington
Major city with 395K population
Unlikely
Dallas
North Texas metropolis with prairie aurora viewing during strong storms
Unlikely
Oklahoma City
Oklahoma capital with Great Plains aurora viewing during geomagnetic events
Unlikely
Learn More About the Northern Lights
Northern Lights in San Antonio: Quick Guide
How often can you see northern lights in San Antonio?
Based on its magnetic latitude of 39.0°, aurora viewing in San Antonio is extremely rare (visible only during exceptional geomagnetic storms). Actual frequency varies with the 11-year solar cycle.
Best viewing season: September to March, with peak activity during equinoxes (September and March).
What Kp index do I need to see aurora in San Antonio?
For San Antonio, you need a minimum Kp index of 9.0 for aurora to be visible. This threshold is calculated based on the city's magnetic latitude (39.0°).
Higher Kp values produce brighter, more active displays:
- Kp 9.0+: Strong, colorful displays visible even with some light pollution
Where should I look for aurora in San Antonio?
Aurora is rarely visible this far south. When it does appear during extreme storms (Kp 7+), look for a faint glow on the northern horizon.
For best results, seek locations with minimal light pollution and unobstructed views of the sky. From San Antonio, aurora typically remains closer to the horizon, so elevated viewing locations help.
Can I see northern lights tonight in San Antonio?
Unlikely: Aurora unlikely tonight with Kp 5.3 (below 9.0 threshold for San Antonio). Enable alerts to catch future opportunities.
Check the live forecast above for the latest updates.