Sun Images for Past 72 Hours
Images copyrighted by the SDO/NASA and Helioviewer project
📋 Propagation Summary: HF propagation today is shaped by moderate solar activity with a solar flux of 114 and a sunspot number of 77. The K-index is at 0, indicating very quiet geomagnetic conditions—great news for stable HF operation and low noise. Expect good conditions on 80m, 40m, and 20m throughout the day and night, while higher bands (17m, 15m) are only fair, and 12m/10m are mostly poor. No major space weather alerts are present, so operators can enjoy reliable contacts, especially on the lower and mid bands. Take advantage of the calm geomagnetic field for DX and regional work, but keep expectations modest on the higher bands.
💡 Operator Tips
- Focus on 80m, 40m, and 20m for both local and DX contacts—these bands are performing best today.
- Use digital modes (FT8, PSK31) on 17m and 15m to maximize chances during fair conditions.
- SSB and CW will be effective on 80m, 40m, and 20m; try CW for marginal band openings.
- Monitor grayline times for enhanced DX, especially on 40m and 20m.
- VHF/UHF: No auroral or enhanced propagation expected; stick to routine operations.
- For contests or DXing, target sunrise/sunset periods for best long-haul propagation.
⏰ Best Operating Times
| Band | Best Times (UTC) |
|---|---|
| 80m | Night, Early Morning |
| 40m | Night, Early Morning, Evening |
| 20m | Daytime, Late Afternoon, Evening |
| 17m | Late Morning, Early Afternoon |
| 15m | Midday, Early Afternoon |
| 12m | Brief midday openings possible |
| 10m | Limited, check midday for short skip |
🌍 DX Opportunities
- Grayline paths are promising on 40m and 20m—watch for enhanced signals at sunrise and sunset.
- 20m is open for intercontinental DX during daylight and early evening.
- 17m/15m: Look for sporadic openings, especially on north-south paths.
- No significant aurora or polar openings expected.
- Special events: No major solar disturbances, so stable conditions favor planned DXpeditions and contests.
📻 Band-by-Band Analysis
| Band | Morning | Day | Evening | Night |
|---|---|---|---|---|
| 80m | 🟡 Good | 🟡 Good | 🟡 Good | 🟡 Good |
| 40m | 🟡 Good | 🟡 Good | 🟡 Good | 🟡 Good |
| 20m | 🟡 Good | 🟡 Good | 🟡 Good | 🟡 Good |
| 17m | 🟠 Fair | 🟠 Fair | 🟠 Fair | 🟠 Fair |
| 15m | 🟠 Fair | 🟠 Fair | 🟠 Fair | 🟠 Fair |
| 12m | 🔴 Poor | 🔴 Poor | 🔴 Poor | 🔴 Poor |
| 10m | 🔴 Poor | 🔴 Poor | 🔴 Poor | 🔴 Poor |
80m, 40m, and 20m are providing the most reliable propagation throughout the day and night, making them the best choices for both local and DX contacts. 17m and 15m offer fair conditions—digital modes will help here, especially around midday. 12m and 10m are largely closed, with only brief or weak openings possible during peak solar hours.
📊 Current Solar Activity
Solar Activity Metrics
K-index
Solar Flux (10.7cm)
Sunspot Number
- K-index: 0 (very quiet)—minimal geomagnetic disturbance, low noise, and stable propagation.
- Solar Flux: 114—moderate level, supporting good low/mid-band conditions but limiting higher bands.
- Sunspot Number: 77—enough for decent 20m/17m/15m activity, but not enough for strong 10m openings.
- Space Weather: No major flares or disturbances; X-ray flux at B4.6 (quiet).
📈 Geomagnetic Conditions
The K-index has remained very low and stable over the past 24 hours, indicating a quiet geomagnetic field. This trend means operators can expect minimal fading, low noise, and no auroral disruptions. These are some of the best geomagnetic conditions for HF operation, especially for DX on the lower bands.
🌟 Space Weather Details
Space Weather Dashboard
X-ray Activity
Solar Wind Speed
Aurora Activity
- X-ray Activity: B4.6 (very low)—no risk of HF blackouts or sudden ionospheric disturbances.
- Solar Wind Speed: 440.8 km/s—moderate, but not enough to trigger geomagnetic storms.
- Particle Environment:
- Electron Flux: 1740—elevated but not extreme; may cause minor absorption at high latitudes.
- Proton Flux: 17—quiet, no polar cap absorption expected.
- Aurora Activity: 2 (very low)—no auroral propagation, VHF/UHF enhancement unlikely.
- Helium Line: 113.4—stable, indicating no major solar upswings or flare activity.
📡 Propagation Timeline & Technical Details
Propagation Quality Timeline (24 Hours)
Recent months have shown a declining trend in both solar flux and sunspot numbers, with solar flux dropping from 138 in June to 116 in August, and sunspots from 94 to 76. This gradual decrease means high bands (12m/10m) are less likely to open, but the lower bands remain robust. The current stable conditions are favorable for reliable operation on 80m–20m.
Solar Activity Trends (6 Months)
🔮 3-Day Forecast
3-Day K-index Forecast
- Solar activity is expected to remain moderate, with no major flares or geomagnetic storms forecast.
- K-index likely to stay low, supporting continued good propagation on 80m–20m.
- 12m/10m: Only brief or weak openings expected; check midday for possible short skip.
- Best bands: 80m, 40m, 20m for both local and DX; 17m/15m for digital and short-haul.
- No alerts or warnings for HF or VHF operators—enjoy the stable bands!