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 and very quiet geomagnetic conditions. The solar flux has dipped to 99, with a sunspot number of 47, reflecting a recent downward trend from the past several months. Expect good conditions on 20m throughout the day and night, while higher bands (12m, 10m) are mostly closed or poor. Low K-index (1) means stable, low-noise bands, making this a great day for reliable regional and some DX contacts, especially on the lower and mid bands. Operators should focus on 20m and 40m for best results, with 80m coming alive at night.
💡 Operator Tips:
- Use 20m and 40m for daytime and evening DX; 80m shines after dark for local/regional QSOs.
- Digital modes (FT8, PSK31) will outperform SSB/CW on marginal bands like 15m and 17m.
- Vertical antennas or dipoles at moderate height will maximize low-angle DX, especially with low geomagnetic disturbance.
- Monitor grayline times for enhanced long-path opportunities, especially on 40m and 20m.
- With low solar flux, QRP stations should stick to lower bands and digital modes for best reach.
⏰ Best Operating Times
| Band | Best Time (UTC) | Notes |
|---|---|---|
| 80m | Night, Early Morning | Strongest after sunset |
| 40m | Night, Early Morning | Good all night, fair daytime |
| 20m | All Day & Night | Most reliable for DX |
| 17m | Midday, Afternoon | Sporadic openings, fair conditions |
| 15m | Midday, Afternoon | Limited, better for digital |
| 12m | Rare, Midday | Mostly poor, check for brief openings |
| 10m | Rare, Midday | Mostly closed, check for E-skip |
🌍 DX Opportunities
- 20m offers the best shot at worldwide DX, especially along the grayline at sunrise/sunset.
- 40m is open for transcontinental and intercontinental paths during local night.
- 17m and 15m may provide short, sporadic DX windows around local noon—watch cluster spots.
- Grayline enhancement: Watch for improved signals to antipodal regions at dawn/dusk on 40m/20m.
- Aurora is minimal (level 1), so no auroral propagation expected on VHF/UHF.
📻 Band-by-Band Analysis
| Band | Morning | Day | Evening | Night |
|---|---|---|---|---|
| 80m | 🟠 Fair | 🟠 Fair | 🟡 Good | 🟡 Good |
| 40m | 🟠 Fair | 🟠 Fair | 🟡 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 |
Analysis:
20m is the most reliable band for both DX and regional contacts at any time of day. 40m and 80m are best at night and early morning for local and regional work, with fair daytime performance. 17m and 15m are marginal—try digital modes for any chance of DX. 12m and 10m are largely closed due to low solar flux; only brief, rare openings possible, especially during midday.
📊 Current Solar Activity
Solar Activity Metrics
K-index
Solar Flux (10.7cm)
Sunspot Number
- K-index: 1 (very quiet)
Indicates minimal geomagnetic disturbance, resulting in low band noise and stable propagation. - Solar Flux (10.7cm): 99
Lower than recent months, meaning higher bands (15m/12m/10m) are less likely to open. - Sunspot Number: 47
A significant drop from earlier in the year, correlating with weaker ionization and higher MUF decline. - Space Weather Overview:
- X-ray: B3.9 (low, no blackout risk)
- Aurora: 1 (very low, no auroral propagation)
- Helium Line: 101.0 (stable, no major solar trend shifts)
📈 Geomagnetic Conditions
- The K-index has remained very low and stable (0-1) over the past 24 hours.
- No geomagnetic storms or disturbances—conditions are quiet and favorable for HF, especially for polar and high-latitude paths.
- Expect minimal absorption and low noise on all bands.
🌟 Space Weather Details
Space Weather Dashboard
X-ray Activity
Solar Wind Speed
Aurora Activity
- X-ray Activity: B3.9 (very low)—no risk of sudden HF blackouts or D-layer absorption events.
- Solar Wind: 456.6 km/s—moderate, but not enough to trigger geomagnetic activity.
- Particle Environment:
- Electron Flux: 2310—slightly elevated, but no significant impact on HF.
- Proton Flux: 10—quiet, no polar cap absorption expected.
- Aurora Activity: Level 1—no auroral propagation; VHF/UHF bands remain unaffected.
- Helium Line: 101.0—indicates steady solar output, with no major flare or CME activity.
📡 Propagation Timeline & Technical Details
Propagation Quality Timeline (24 Hours)
- Recent solar flux and sunspot numbers have trended downward since late 2025, with a notable drop in both metrics since January 2026.
- This decline leads to lower MUF, especially impacting 15m and above.
- 20m and 40m remain resilient due to their lower frequency requirements.
- No major solar events in the past month; propagation is shaped mainly by the gradual solar cycle decline.
Solar Activity Trends (6 Months)
🔮 3-Day Forecast
3-Day K-index Forecast
- Solar activity is expected to remain low, with no significant flares or CMEs forecast.
- K-index should stay quiet (0-2), keeping band noise low and propagation stable.
- Best bands: 20m, 40m, and 80m (night); Worst bands: 12m, 10m (mostly closed).
- No alerts or warnings for HF or VHF operators.
- Recommendation: Focus on lower bands for reliable contacts; monitor 17m/15m for brief digital-mode DX windows around local noon.