Sun Images for Past 72 Hours
Images copyrighted by the SDO/NASA and Helioviewer project
📋 Propagation Summary: HF propagation today is shaped by a moderately high solar flux of 163 and a sunspot number of 99, supporting good conditions on the higher bands (20m–10m) during daylight hours. However, a K-index of 3 and elevated solar wind speed (655.9 km/s) mean geomagnetic activity is slightly unsettled, which may cause some fading and less reliable paths, especially at higher latitudes. Lower bands (80m, 40m) are underperforming during the day but improve somewhat at night. For best results, focus on the 20m–10m bands during the day and 20m–15m into the evening. Watch for short-lived DX openings, especially around grayline.
💡 Operator Tips:
- Use 20m, 17m, and 15m for reliable daytime DX and regional contacts.
- Digital modes (FT8, FT4, PSK) will help punch through minor disturbances.
- 80m and 40m are best reserved for local and regional contacts after dark.
- Monitor the K-index: if it rises above 4, expect increased absorption and fading, especially on polar and trans-equatorial paths.
- For contests or DXing, check the grayline for enhanced propagation, especially on 20m and 17m.
- Keep antennas optimized for higher bands during the day and lower bands at night.
⏰ Best Operating Times
| Band | Best Times (UTC) | Notes |
|---|---|---|
| 80m | 20:00–07:00 | Nighttime only; daytime absorption high |
| 40m | 19:00–08:00 | Night, early morning; poor daytime |
| 20m | 08:00–20:00 | All day; good DX, especially grayline |
| 17m | 09:00–19:00 | Daytime DX, some evening openings |
| 15m | 10:00–18:00 | Daytime DX, best mid-day |
| 12m | 11:00–17:00 | Daytime only; closes quickly at dusk |
| 10m | 12:00–16:00 | Short daytime window; watch for sporadic |
🌍 DX Opportunities
- 20m and 17m: Good transcontinental and intercontinental paths during daylight and around grayline.
- 15m and 12m: Open for DX during mid-day, especially on north-south paths.
- 10m: Watch for brief openings, especially if sporadic-E is present.
- Grayline: Enhanced propagation on 20m and 17m at sunrise/sunset—target distant DX.
- Aurora: Moderate aurora (level 3) may provide VHF auroral propagation for northern operators.
- Special Events: Elevated X-ray flux (C1.4) could trigger short HF blackouts, especially on sunlit paths.
📻 Band-by-Band Analysis
| Band | Morning | Day | Evening | Night |
|---|---|---|---|---|
| 80m | 🔴 Poor | 🔴 Poor | 🟠 Fair | 🟠 Fair |
| 40m | 🔴 Poor | 🔴 Poor | 🟠 Fair | 🟠 Fair |
| 20m | 🟡 Good | 🟡 Good | 🟡 Good | 🟡 Good |
| 17m | 🟡 Good | 🟡 Good | 🟡 Good | 🟡 Good |
| 15m | 🟡 Good | 🟡 Good | 🟡 Good | 🟡 Good |
| 12m | 🟡 Good | 🟡 Good | 🔴 Poor | 🔴 Poor |
| 10m | 🟡 Good | 🟡 Good | 🔴 Poor | 🔴 Poor |
The 20m, 17m, and 15m bands are the most reliable throughout the day and evening, offering consistent regional and DX contacts. 12m and 10m are open during daylight but close rapidly after sunset. 80m and 40m are underperforming during the day but become usable for local/regional QSOs at night.
📊 Current Solar Activity
Solar Activity Metrics
K-index
Solar Flux (10.7cm)
Sunspot Number
- K-index: 3 — Slightly unsettled; minor geomagnetic disturbances possible, especially at higher latitudes.
- Solar Flux: 163 — Above average; supports strong F-layer ionization and good high-band propagation.
- Sunspot Number: 99 — Healthy; enough sunspots to keep upper bands open, but not at solar maximum.
- Space Weather: X-ray flux at C1.4 indicates moderate flare activity; watch for brief HF blackouts on sunlit paths.
📈 Geomagnetic Conditions
- The K-index has been fluctuating between 2 and 3 over the past 24 hours, indicating slightly unsettled geomagnetic conditions.
- No major geomagnetic storms, but minor disturbances may cause some signal fading and absorption, especially on polar paths.
- Trends are stable to slightly unsettled; monitor for any spikes above K=4 which could quickly degrade HF conditions.
🌟 Space Weather Details
Space Weather Dashboard
X-ray Activity
Solar Wind Speed
Aurora Activity
- X-ray Activity: C1.4 level—moderate solar flare activity. Occasional short HF blackouts possible, especially on the sunlit side of Earth.
- Solar Wind: 655.9 km/s—elevated speed; can enhance geomagnetic activity and cause minor disturbances.
- Particle Environment:
- Electron Flux: 1580 — Elevated; may contribute to increased absorption on lower bands.
- Proton Flux: 21 — Normal; no significant proton events.
- Aurora Activity: Level 3 — Moderate; possible auroral propagation on VHF for high-latitude stations.
- Helium Line: 122.1 — Indicates ongoing solar activity, but not at peak levels; trend is steady.
📡 Propagation Timeline & Technical Details
Propagation Quality Timeline (24 Hours)
- Over the past several months, solar flux has decreased from a high of 160+ to the current 125–163 range, and sunspot numbers have dipped but remain healthy (recently 99–101).
- This trend suggests we are past the solar cycle peak, but conditions remain favorable for high-band HF operation.
- Watch for further declines in solar flux and sunspots, which may gradually shorten high-band openings in coming months.
Solar Activity Trends (6 Months)
🔮 3-Day Forecast