Aurora Borealis Forecast – Kp Index & Visibility

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Aurora Borealis Forecast

Real-time Kp index monitoring & aurora visibility prediction

3.67 Kp Index

Active

Updated: Just now

Solar Wind Conditions

Speed

452

km/s

B_z

-3.5

nT (Southward ✓)

Density

8.2

p/cm³

6.1

Bz southward (-) means solar wind magnetic field is favorable for aurora formation. Negative Bz = better chances!

Your Visibility

Select City or Enter Latitude

Select a location to check visibility

3-Day Kp Forecast

Data updates every 3 hours · NOAA SWPC

Kp 0-1: Quiet Kp 2-3: Unsettled Kp 4: Active Kp 5: Minor Storm Kp 6: Moderate Kp 7: Strong Kp 8: Severe Kp 9: Extreme

Kp Index & Visibility Guide

Kp	Level	G-Scale	Visible From Latitude	Frequency
0 – 1	Quiet	G0	66°N+ (Arctic Circle)	Very common
2 – 3	Unsettled	G0	64°N+	Common
4	Active	G0	60°N+	Several per month
5	Minor Storm	G1	57°N+	~900 days per cycle
6	Moderate Storm	G2	53°N+	~360 days per cycle
7	Strong Storm	G3	48°N+	~130 days per cycle
8	Severe Storm	G4	42°N+	~60 days per cycle
9	Extreme Storm	G5	38°N+ (rare!)	~4 days per cycle

Best Viewing Tips

Go out between 10 PM – 2 AM local time
Find clear, dark skies away from city lights
Look toward the northern horizon (north = best)
Best months: September – April
Use a camera – sensors catch more than eyes
Check local weather – clouds block aurora
Dress warmly – clear nights are often coldest
Monitor Bz – negative = better aurora

Frequently Asked Questions

What is the Kp Index?

The Kp Index (Planetary K-index) is a global measure of geomagnetic activity on a scale from 0 to 9. It represents the disturbance in Earth's magnetic field caused by solar wind. The higher the Kp number, the stronger the aurora and the farther south (or north in the Southern Hemisphere) the aurora can be seen. Kp is calculated every 3 hours from data collected by a network of magnetometers around the world.

What Kp level do I need to see the Northern Lights?

It depends entirely on your latitude:
• Above 66°N (Arctic Circle): Kp 0–1 is enough
• 64–66°N: Kp 2–3
• 60–64°N: Kp 4
• 55–60°N: Kp 5
• 50–55°N: Kp 6
• Below 45°N: Kp 7+ (rare but possible during strong storms)
Use our visibility checker above to see your chances!

What is Bz and why is it important?

Bz is the north-south component of the interplanetary magnetic field (IMF). When Bz is negative (southward), it means the solar wind's magnetic field points opposite to Earth's, allowing solar particles to enter our atmosphere along magnetic field lines – creating aurora. A strongly negative Bz (-5 nT or lower) dramatically increases aurora activity, even if Kp is moderate.

When is the best time to see the Aurora Borealis?

The best time is typically September through April in the Northern Hemisphere, when nights are long and dark. During summer months (May–August), high-latitude regions experience the "Midnight Sun" where it never gets fully dark, making aurora invisible. The peak hours are 10 PM to 2 AM local time (around magnetic midnight). The solar cycle also matters – we're currently approaching Solar Maximum (2024–2025), meaning increased aurora activity!

Can I see the Aurora Australis (Southern Lights)?

Yes! The Aurora Australis is the Southern Hemisphere's equivalent of the Northern Lights. The same Kp index applies, but you need to be at southern latitudes. Best viewing locations include Tasmania, New Zealand's South Island, southern Argentina/Chile (Patagonia), and Antarctica. For the Southern Lights, Kp 4+ is typically needed from inhabited areas like Hobart or Invercargill.

How accurate are aurora forecasts?

Short-term forecasts (1–3 days) are moderately reliable because they're based on observed solar activity and coronal mass ejections (CMEs) already detected. However, aurora can appear with as little as 30–60 minutes' notice. For the best real-time tracking, monitor live solar wind data (Bz, speed, density) from satellites like DSCOVR and check magnetometer readings. The 3-day Kp forecast gives a good general outlook, but conditions can change rapidly.

What colors can the aurora display?

Aurora colors depend on which atmospheric gases are excited and at what altitude:
• Green – Oxygen at ~100–300 km (most common)
• Red – Oxygen above ~300 km (rare, during strong storms)
• Purple/Pink – Nitrogen at lower altitudes (~100 km)
• Blue – Nitrogen at very low altitudes (rare)
During intense storms (G3+), you may see multiple colors dancing together!

How do I photograph the Northern Lights?

For aurora photography, use a camera with manual controls:
• Wide-angle lens (f/2.8 or faster ideal)
• ISO 800–3200 (depending on aurora brightness)
• Shutter speed 2–15 seconds (shorter for fast-moving aurora)
• Sturdy tripod – absolutely essential
• Manual focus set to infinity
• Shoot in RAW format for better post-processing
Pro tip: Use a remote shutter or 2-second timer to avoid camera shake!

What is the difference between Kp and the G-scale?

The G-scale (NOAA Space Weather Scale) describes geomagnetic storm severity:
• G1 (Minor) = Kp 5
• G2 (Moderate) = Kp 6
• G3 (Strong) = Kp 7
• G4 (Severe) = Kp 8
• G5 (Extreme) = Kp 9
While Kp is a continuous measurement, the G-scale is used for official warnings. A G1 watch means aurora may be visible from higher mid-latitudes.

Where does this forecast data come from?

This tool displays simulated forecast data for demonstration. Real aurora forecasts come from NOAA's Space Weather Prediction Center (SWPC), which uses data from the DSCOVR satellite (located at Lagrange point L1, ~1.5 million km from Earth) and a global network of magnetometers. For real-time data, visit swpc.noaa.gov. The 3-day Kp forecast is issued by NOAA SWPC and updated every 3 hours.

Aurora Borealis Forecast Tool · Kp Index data simulated for demonstration · For live data visit NOAA SWPC · Solar Maximum 2024–2025 is here – prime aurora viewing!