The bands and the weather are measured a few metres apart and behave nothing alike. Space weather comes from outside; everything on the rest of this site is measured here.
| Band | Day | Night |
|---|---|---|
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These are modelled from the indices, not measured on air. They say what the ionosphere should support, which is a different claim from what you will actually hear — and the gap between the two is most of what makes the hobby interesting.
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The European E-skip rows are the ones that matter at this latitude. A 6 m opening to the continent is the difference between a dead band and an afternoon of work.
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| Height | Temp | RH | N | dN/dh above |
|---|
Radio waves bend because air gets thinner with height. What decides how much is the vertical gradient of refractivity, dN/dh, in N-units per kilometre. Around −39 is the ordinary atmosphere. Past −79 rays bend down faster than usual and range extends; past −157 they bend as hard as the earth curves, the layer stops letting energy escape upward, and it becomes a duct — which is how a 2 m signal turns up several hundred kilometres away. Humidity falling sharply with height does this more often than temperature does, which is why the wettest, stillest nights are the ones worth staying up for.
Two things this cannot do. The model's levels are about 200 m apart, and surface ducts on this coast are often thinner than that, so a quiet answer here is much weaker evidence than a loud one — it can tell you a duct is forecast and it cannot tell you there is none. And a duct has to exist along the whole path, not just over this field: this is one grid point, and the station at the far end is standing in different air.
| Model said | Decodes | Median reach | Furthest |
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Great-circle paths from this station · Tiles © Esri — Esri, HERE, Garmin, © OpenStreetMap contributors
| Heard by | Band | SNR | Distance | When |
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| Date | Spots | Receivers | Furthest |
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Terminator computed for this station’s clock · Tiles © Esri — Esri, HERE, Garmin, © OpenStreetMap contributors
| Satellite | Rises | Peak | Sets | Length | Track |
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Kp below 3 is quiet. From about 5 it is a geomagnetic storm: HF paths over high latitudes degrade first, aurora becomes possible, and the higher bands close. A single current figure cannot show a storm arriving — the shape can.
Solar indices and band conditions by N0NBH, hamqsl.com. Planetary K index from NOAA SWPC. Satellite element sets from CelesTrak, pulled by group every six hours — their own update rate — and propagated here rather than fetched per satellite. The refractivity profile behind the ducting panel from Open-Meteo's pressure levels. All free and unauthenticated, fetched on a schedule and cached here — so opening this page costs them nothing, however many people do it.