Solar Cycle 25: A Stronger-Than-Expected Cycle

When Solar Cycle 25 began around late 2019, initial forecasts from NOAA and the international solar prediction panel were conservative — predicting a moderate cycle similar to the relatively quiet Cycle 24. Those predictions have proven to be significantly off. Cycle 25 has shown considerably higher activity than forecast, with sunspot numbers and Solar Flux Index (SFI) values tracking well above predicted levels as the cycle approaches and passes its peak.

For amateur radio operators and DXers, this is genuinely exciting news. A more active solar cycle means better HF propagation — particularly on the higher frequency bands that had been essentially dormant during the quiet years of Cycle 24's minimum.

What Higher Solar Activity Means for the Bands

Elevated solar flux translates directly to improved ionospheric conditions. Here's how different bands are benefiting:

  • 10 meters (28 MHz): Perhaps the biggest story of the cycle. The 10m band was largely closed for extended periods during solar minimum. Now, during active periods, it's showing remarkable worldwide openings — including paths that were rare even in past cycles. Trans-equatorial propagation (TEP) and F2 skip are bringing in stations from all corners of the world.
  • 12 meters (24 MHz) and 15 meters (21 MHz): Both bands are performing reliably for DX throughout daylight hours, with paths open to multiple continents simultaneously on most days.
  • 17 meters (18 MHz) and 20 meters (14 MHz): Consistently excellent. These bands are benefiting from improved conditions while remaining reliable even on days with moderate solar flux.
  • 40 meters (7 MHz) and 80 meters (3.5 MHz): Night DX on these bands continues to be productive, with the added benefit that daytime D-layer absorption — while present — is somewhat offset by the overall improved conditions.

Notable DXpeditions in 2025

The improved propagation has energized the DXpedition community, with several significant activations planned or completed in 2025. Some themes and trends in recent DXpedition activity include:

  • Increased activity on the higher bands (10m–15m) to take advantage of Cycle 25 conditions
  • Greater use of FT8 and FT4 alongside CW and SSB to maximize contact rates and reach more operators
  • More focus on activating entities that haven't been on the air for several years — rarer entities that many operators still need
  • Online live logging and real-time OQRS systems making confirmations faster than ever

Operators are encouraged to monitor DX World (dx-world.net), the Daily DX newsletter, and the ARRL DX Bulletin for up-to-date DXpedition announcements and schedules.

Geomagnetic Disturbances: The Flip Side

Higher solar activity brings a caveat: more frequent and intense geomagnetic storms. When solar flares and coronal mass ejections (CMEs) interact with Earth's magnetic field, propagation can be severely disrupted — particularly on polar paths. The K-index and A-index are your early warning system. When K rises above 4–5, expect degraded conditions, especially on north-south paths across the polar regions. These disturbances typically last 12–48 hours before conditions recover.

The good news: space weather forecasting has improved substantially, and NOAA's Space Weather Prediction Center provides alerts and forecasts that let operators anticipate disruptions rather than be surprised by them.

Advice for DXers Right Now

  1. Get on 10 meters. If you haven't operated 10m in years, now is the time. Openings to rare entities on 10m are happening regularly.
  2. Check propagation tools daily. DX Maps, PSKReporter, and the NOAA SFI readings should be part of your daily routine.
  3. Don't ignore the grey line. The grey-line enhancement effect is especially powerful during high solar activity — set alarms for your local sunrise and sunset.
  4. Log everything. Current conditions may be the best you'll see until Cycle 26. Work everything you can and confirm via LoTW promptly.

Looking Ahead

The peak of Solar Cycle 25 is expected sometime in the 2024–2025 timeframe, after which activity will gradually decline toward the next minimum — likely in the early 2030s. The window for exceptional high-band DX is open now. Make the most of it.