HF Propagation & Space Weather
Is the ionosphere cooperating today? Live Kp, solar flux and HF band conditions, explained.
About this tool
Kp index
Kp measures disturbance of Earth's magnetic field on a 0–9 scale. Below 3 is quiet and good for HF; 5 and above is a geomagnetic storm, which degrades HF (especially polar paths) but brings aurora and VHF auroral openings.
Solar flux (F10.7)
The Sun's radio output at 10.7 cm tracks how strongly the ionosphere is ionised. Higher flux means higher usable frequencies: above about 120, the 15, 12 and 10 m bands open for long-distance contacts.
Data sources
Kp and solar flux from NOAA's Space Weather Prediction Center; band conditions from hamqsl.com by N0NBH. Refreshed about every 15 minutes.