Live Data · Updated Every 15 Min
HF Propagation
Live solar conditions from NOAA — MUF estimates, gray-line map, and band-by-band outlook calculated from the current Solar Flux Index and K-index. Refreshes automatically every 15 minutes.
📡 Live HF Propagation & Solar Conditions
Live solar data from NOAA, updated every 15 minutes. MUF (Maximum Usable Frequency) estimates are calculated from the current Solar Flux Index and K-index — they reflect typical SoCal-to-target-region propagation. Gray-line updates in real time based on UTC.
| Target Region | Distance | Est. MUF | Best Bands Now | Outlook |
|---|---|---|---|---|
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Reading the MUF: The MUF is the highest frequency that the ionosphere will currently refract back to Earth for a given path.
Operating below the MUF gives you the best chance of a contact — closer to the MUF means weaker but more reliable signals.
High solar flux (SFI > 150) raises the MUF and opens the higher bands (10m–17m). High K-index (> 3) indicates geomagnetic disturbance
and degrades or kills HF propagation, especially at higher latitudes.
🌓 Gray-Line Timing — Current UTC: —
The gray-line is the twilight zone sweeping westward at ~1,040 mph. Best DX happens when it crosses both your QTH and your target simultaneously — within ~30 min of your local sunrise or sunset.
| Target | Their Sunrise (UTC) | Their Sunset (UTC) | Shared Window? | Status Now |
|---|---|---|---|---|
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