HF Propagation Forecast & Solar Data

Open How is this score calculated, just under the score itself. It lists every component with its current reading, its own 0 to 100 mark and the weight it carries, and the column adds up to the figure on the dial. Two things in that table are worth knowing. Where a source is unavailable its weight is shared out across the rest, so the score stays on the same scale instead of being quietly dragged down. And on-air activity is listed but ranks the bands only: it carries no weight in the headline number.

Because the two are answering different questions. The overall score comes from the space weather model alone. The band ranking underneath takes that model and blends in how busy each band actually is on the DX cluster right now, so a band can be crowded and productive on an otherwise mediocre day. When they disagree, the band ranking is usually the one worth acting on.

Up to 60 per cent of a band’s score. Each band is scored as the propagation model blended with its share of the busiest band’s spots over the last hour, and the weight of that activity rises with traffic: under about 30 spots the model still dominates, above it the blend settles at 60 per cent. If the feed is empty or more than two hours old, the ranking falls back to the model alone.

The solar and geomagnetic figures are re-read every ten minutes. The planetary K index behind them is only published every three hours, so that part of the score moves in steps rather than smoothly. The spot activity is recomputed over a rolling sixty minute window each time the page refreshes.

Only the grey line component depends on where you are, because sunrise and sunset move with your longitude. Solar flux, the geomagnetic index, the solar wind and the X-ray readings are planetary figures and are identical for everyone looking at this page.

It is a broad estimate for the ionosphere overhead, not for the path you want to work. A MUF of 11 MHz does not mean 20 metres is shut: on a long path the signal leaves at a shallower angle and can still refract well above the vertical figure. Use it to see which way the ceiling is moving, not as a hard cut-off.

No, and that is not false modesty. Sporadic E can open 10 metres in minutes without moving any of the numbers here, and a noisy street can close a band the model calls wide open. The score tells you where to tune first. Your ears decide what happens next.

Yes. The same data comes from a public endpoint on this site, /wp-json/g7rdx/v1/propagation, which returns the overall score, the per band scores with their spot counts, and the raw solar figures as JSON. No key is needed. Please cache it rather than polling it every few seconds.