HF Propagation Dashboard

User Guide

This dashboard answers a practical question for your station: which HF bands are likely usable right now, and to where. It shows that two ways side by side, a physics forecast and what stations are actually being heard from your area this hour. It never blends the two into a single guess; it shows you both and tells you whether they agree.

On this page

Getting started

Everything is computed for your location, so the first thing the site asks for is where you are. Tap the 📍 location chip in the header and either:

Your choice is stored in your browser only (nothing is sent to an account) and remembered next time. You can change it whenever you travel. The forecast refreshes automatically every few minutes; the header shows a countdown and a Refresh button for an immediate update.

Once set, the location chip also names the country your point falls in, for example "IO91wm · England". This is worked out on the server from a public-domain map of borders; your coordinates are not sent to any outside service. A point right on a coastline or border can occasionally come out blank or just the wrong side of a line, which does not affect the forecast itself.

The footer shows a small "online now" figure. That is how many people currently have the site open, not how many stations are on the air (the Activity and Map pages show real on-air stations). It is a live count that resets over time and stores nothing about you.

The core idea: Predicted vs Observed

Every band, for every distance range, shows two independent numbers on a 0–10 scale:

Predicted
A pure physics forecast: given the current ionosphere (measured by ground stations) and solar/geomagnetic conditions, can a signal physically make this hop on this band? This is the colour and the Open / Fair / Poor / Closed label of each band.
Observed
What's actually being heard from your area in the last hour, gathered from worldwide automatic receiver networks. This is real evidence, not a model.
The two are shown side by side and never averaged together. A forecast and a measurement answer different questions; mashing them into one number hides exactly the disagreements that are most worth knowing about. Instead, a small indicator tells you whether reality is agreeing with the forecast, beating it, or falling short.

Distance ranges

A band is rarely "open" or "closed" everywhere at once; it depends how far you're trying to reach. The forecast is broken into four ranges (great-circle distance from you), plus an Overall summary that picks the best of them:

RangeDistanceTypical use
Local0–500 kmNear neighbours, NVIS, groundwave
Regional500–1500 kmAcross a country, into neighbouring nations
Continental1500–3000 kmContinent-wide, one long hop
DX3000 km +Intercontinental, long-haul

The same band can be Closed locally but Open for DX (a "skip zone"), or the reverse. Use the Target control to focus on the range you care about.

Reading a band

In Detail view each band card shows, for the chosen Target range:

When the Target is set to Overall, each Detail and Summary card also carries a small strip of four bars along the bottom, one per distance range (Local, Regional, Continental, DX). Each bar is coloured by the Predicted verdict for that range, so you can see the whole distance gradient at a glance without changing the Target: a band that reads Fair overall might in fact be closed locally and only open for DX. A small caret marks the range that is driving the Overall headline. Hover or tap a bar for its Predicted and Observed numbers.

Summary view distils that to a headline; hover (or tap) any Summary card to pop up the same full Detail breakdown for that band. Matrix view compresses it to a single coloured cell per band × range. In every view the rule is the same: cell/pill colour = Predicted, the mark = Observed.

Indicators & mode badges

The small mark beside each band tells you how the live evidence compares to the forecast:

🟢 / ✓ Aligned
Reality matches the forecast, with enough evidence to trust it. The normal "all is as expected" state.
🔵 / ▲ Better than forecast
The band is being heard more than the physics predicted, a positive surprise worth chasing.
🔴 / ▼ Conflict
The physics says the band should be open, but reality is quiet despite plenty of listeners. Trust the evidence over the model here.
⚪ / ◦ Unconfirmed
Little or no evidence either way (few or no receivers heard you). Lean on the forecast. This is normal for quiet bands and quiet hours; it is not a problem.

When a short-range opening is better explained by a special mode, the indicator is replaced by a named badge:

🟧 Es (Sporadic-E)
A short hop on a high band (15 m and up) that ordinary F-layer propagation can't make: the summer "chase it" mode. Only flagged when proven by real workable signals, not beacons alone.
🟪 NVIS / groundwave
A low band heard locally by near-vertical sky-wave or groundwave: short-range coverage the long-distance forecast doesn't model.
In the Matrix the indicators are deliberately quiet: a faint ✓ or ◦ for the "nothing to flag" states, and a bold blue ▲ or red ▼ only where reality genuinely diverges, so the predicted colour stays the thing your eye reads first. Tap any cell for the full numbers.

The condition tiles

The row of tiles at the top is the space-weather and ionospheric picture for your location. Their colour shows how favourable each is for the higher bands and DX (green good → red poor). Tap the ⓘ on any tile for a plain-English explanation.

SFI (Solar Flux Index)
Global gauge of solar activity. Higher flux ionises the upper ionosphere more, raising the MUF and opening the higher bands.
Kp
Global geomagnetic disturbance (0–9). High Kp means a geomagnetic storm degrading HF, especially on paths near the poles.
Storm
Current geomagnetic storm level (NOAA G-scale). The border reflects conditions now; a separate amber/red watch badge flags a forecast storm in the next day or two.
MUF (at your QTH)
Maximum Usable Frequency for a long (DX) hop, derived from the nearest ionosonde(s). The headline gauge of how high the bands are open.
LUF
Lowest Usable Frequency, the daytime absorption floor. Bands below it are largely closed (D-layer absorption). Low LUF is good.
Window (Local)
Whether it's day, night, or greyline at your location, with sunrise/sunset times. Greyline is often prime DX.

The controls

ControlWhat it does
Location (header chip)Sets the QTH everything is computed for. Geolocate, grid, or lat/lon. Remembered in your browser.
ViewSwitches between Detail, Summary and Matrix layouts (below). Your choice is remembered.
TargetWhich distance range to headline (Overall / Local / Regional / Continental / DX). Hidden in Matrix, which shows all ranges at once.
ModesWhich kind of operating to reflect: Any, Weak-signal (WSPR/FT8/FT4), or CW/SSB (traditional, human-operated). It sets the observed side and, on the low bands, the predicted side too. See the note below.
ShowShow all bands, or hide the ones predicted Closed to reduce clutter.
BandFocus on a single band; the card area then breaks that band out across all four ranges.
ThemeDark, Light, or Auto (follows your device).
The Modes filter is important. The receiver networks hear weak digital modes (WSPR, FT8) far more easily than a human ear hears CW or SSB. A band can look "open" because beacons are getting through at signal levels no voice contact could use. Switch Modes → CW/SSB to see the picture for ordinary contacts; you'll often find the low bands that looked busy go quiet, which is the honest answer. The Predicted side shifts a little too: a more sensitive mode punches through more daytime absorption, so the lowest usable band drops, which is why a band at the edge can read open for FT8 but closed for voice. (Any is the default and changes nothing unless you opt in.)

The Observations chip summarises the live evidence behind the current view: which networks contributed, the mode filter in force, the catchment radius being used, and whether there was enough data to be confident.

The three views

Detail
Full cards: every number, the gate reasoning, and who heard you (countries and networks). Best on a desktop. Default on wide screens.
Summary
Compact cards: the headline per band for the chosen Target. Default on tablets.
Matrix
The tightest view: a grid of every band against every range, colour = Predicted, a small mark = Observed. The only view that shows all ranges at once. Default on phones.

The site picks a sensible default for your screen width, but once you choose a view it remembers it.

The Activity page

The Activity page answers a different question from the forecast: not "is the band open for me?" but "what's on the air right now?" It's a live, browsable picture of worldwide (or local) band activity, drawn from the same spot networks.

Stations are grouped into country cards, sorted into three intensity tiers by how many bands that country is active on:

Each card shows the country, how many distinct callsigns, and a band chip for every band it's active on (with the call count). Tap a band chip to see just that band's recent spots; tap the country to see all bands. The card border colour matches the tier.

ControlWhat it does
AreaGlobal (worldwide), or My area (activity within ~1000 km of your location). Defaults to My area once a location is set.
ViewStations heard (the active transmitters) or Who's hearing (the receivers).
ModesThe same Any / Weak-signal / CW-SSB filter as the forecast, so CW/SSB here shows genuine human voice/CW activity.
WindowHow far back to look (5–60 minutes).

It refreshes every few minutes. Think of it as the live companion to the forecast: the forecast says what should be open for you; Activity shows what's actually happening out there.

Where the voice activity comes from. SSB and CW spots are posted by real operators via the worldwide DX cluster network; we connect through several nodes for reliability (primarily GB7MBC in Morecambe, with a few fallbacks). It's the only source that hears voice, so it's genuinely valuable, but bear in mind operators tend to spot DX and rarer stations rather than everyday local contacts, so it leans toward the interesting end and isn't a full census of the band. That's why it appears here on Activity as a sign of what's about, rather than feeding the forecast's scores.

The Map page

The Map page shows the same live activity as a picture, on a great-circle map centred on your location. It's the spatial companion to Activity: where Activity lists who's on the air, the Map shows where they are relative to you.

The projection (azimuthal-equidistant) is the classic ham "beam-heading" map: a straight line from the centre to any point is the true bearing to aim an antenna, and distance from the centre is true ground distance. North is up; the rings are great-circle distance every 2,500 km, and the edge of the disc is the antipode (~20,000 km away).

Two real things are drawn on it, and nothing is predicted here.

Pick a band to cut through the clutter, choose View (Both / Stations heard / Who's hearing), Modes and the time Window. Scroll or the + / − buttons zoom (toward the cursor), drag to pan, and ⤢ resets the view. The map refreshes itself every few minutes, so it's happy left running on a screen.

Status & data

The Status page is a live, read-only view of the data feeding the site: the latest space-weather figures, the ionosonde stations in use, and how many spots each network is contributing. If a forecast looks off, the Status page shows whether a data source has gone quiet.

For the physics and algorithms behind every number, see How it works.