Sun Images for Past 72 Hours
Images copyrighted by the SDO/NASA and Helioviewer project
📋 Propagation Summary: Today’s HF propagation is being impacted by a combination of low solar flux (106–120), a moderate sunspot number (46–79), and elevated geomagnetic activity (K-index 5). Expect generally poor conditions on most HF bands, with only the 17m and 15m bands showing fair potential for contacts. High solar wind speed and a moderate aurora index may further dampen higher latitude propagation. Operators should focus on digital modes and be prepared for rapid changes, especially on the higher bands. Short skip and DX will be challenging, but local and regional contacts are still possible with persistence.
💡 Operator Tips
- Use FT8, FT4, and other digital modes for best results, as they perform well in weak conditions.
- Lower your expectations for SSB and CW on 80m–20m; focus on 17m and 15m during daylight for any DX.
- Check your antenna system for maximum efficiency—every dB counts today.
- Monitor the K-index and aurora levels if you’re in northern latitudes; sudden blackouts or absorption may occur.
- If contesting or chasing DX, target grayline times and be ready to switch bands quickly.
⏰ Best Operating Times
| Band | Best Time (UTC) | Notes |
|---|---|---|
| 80m | None | Poor both day and night |
| 40m | None | Poor both day and night |
| 20m | None | Poor both day and night |
| 17m | 10:00–16:00 | Fair, best shot at daytime DX |
| 15m | 10:00–16:00 | Fair, possible short openings |
| 12m | None | Poor both day and night |
| 10m | None | Poor both day and night |
🌍 DX Opportunities
- Grayline propagation may offer brief windows on 17m and 15m around local sunrise and sunset.
- Northern paths may be disrupted by auroral activity; southern and equatorial paths are less affected.
- No major DX openings expected, but watch for sporadic E on 15m.
- Keep an ear on beacons and cluster spots for surprise short-lived openings.
📻 Band-by-Band Analysis
| Band | Morning | Day | Evening | Night |
|---|---|---|---|---|
| 80m | 🔴 Poor | 🔴 Poor | 🔴 Poor | 🔴 Poor |
| 40m | 🔴 Poor | 🔴 Poor | 🔴 Poor | 🔴 Poor |
| 20m | 🔴 Poor | 🔴 Poor | 🔴 Poor | 🔴 Poor |
| 17m | 🟠 Fair | 🟠 Fair | 🟠 Fair | 🟠 Fair |
| 15m | 🟠 Fair | 🟠 Fair | 🟠 Fair | 🟠 Fair |
| 12m | 🔴 Poor | 🔴 Poor | 🔴 Poor | 🔴 Poor |
| 10m | 🔴 Poor | 🔴 Poor | 🔴 Poor | 🔴 Poor |
The 17m and 15m bands are your best bets today, offering fair conditions throughout the day and evening, especially for regional contacts or weak-signal DX. All other HF bands (80m–12m, 10m) are rated as poor and are unlikely to support reliable communications. Nighttime does not bring improvement on any band.
📊 Current Solar Activity
Solar Activity Metrics
K-index
Solar Flux (10.7cm)
Sunspot Number
- K-index: 5 (moderate geomagnetic disturbance)—expect increased absorption and fading, especially at higher latitudes.
- Solar Flux: 106 (low)—limits maximum usable frequency (MUF), reducing HF band openings.
- Sunspot Number: 46 (current) / 79 (recent monthly)—below average, further suppressing propagation.
- Space Weather: High solar wind (734 km/s), moderate X-ray flux (B6.4), and elevated electron/proton fluxes all contribute to challenging HF conditions.
📈 Geomagnetic Conditions
- The K-index has reached 5, indicating active geomagnetic conditions.
- Recent trends show a spike from quieter levels, suggesting a recent disturbance (possibly a coronal hole or CME).
- Expect unstable propagation, especially on polar and trans-auroral paths; conditions may improve if the K-index drops back below 4.
🌟 Space Weather Details
Space Weather Dashboard
X-ray Activity
Solar Wind Speed
Aurora Activity
- X-ray Activity: B6.4 (low-to-moderate)—no major blackouts, but minor absorption possible.
- Solar Wind: 734 km/s (very high)—can trigger geomagnetic storms and auroral activity, especially at high latitudes.
- Particle Environment: Electron flux (2360) and proton flux (313) are elevated, which can cause increased D-layer absorption and degraded HF performance.
- Aurora Activity: Index 10—moderate auroral activity; VHF/UHF aurora propagation possible for northern operators, but HF absorption is likely.
- Helium Line: 103.0—indicates low to moderate solar activity, consistent with current poor HF conditions.
📡 Propagation Timeline & Technical Details
Propagation Quality Timeline (24 Hours)
- Over the past several months, solar flux and sunspot numbers have steadily declined from late 2025 highs (F10.7 ~160, SSN ~124) to current lower values (F10.7 ~120, SSN ~79).
- This downward trend is reflected in today’s poor HF conditions, with fewer sunspots and lower solar flux reducing MUF and band openings.
Solar Activity Trends (6 Months)
🔮 3-Day Forecast
3-Day K-index Forecast
- Expect continued poor to fair HF conditions for the next 72 hours, unless the K-index drops significantly.
- 17m and 15m will remain the most reliable bands for any DX or regional contacts.
- Watch for possible brief improvements if geomagnetic activity subsides, but plan for challenging propagation overall.
- No major solar flares or space weather alerts are forecast, but stay tuned for updates if conditions change.