Sun Images for Past 72 Hours

Images copyrighted by the SDO/NASA and Helioviewer project
📋 Propagation Summary:
HF propagation today is shaped by low solar flux (89-105) and a low sunspot number (22-60), resulting in fair to poor conditions on most bands above 20m. The geomagnetic field is very quiet (K-index 0-1), which helps stabilize lower band performance, especially at night. Expect best results on 80m and 40m after sunset, while higher bands (20m and up) will be challenging for long-haul DX. No major solar storms or aurora events are present, so operators should focus on local and regional contacts and take advantage of the quiet geomagnetic field. Digital modes will outperform SSB/CW on marginal bands.
💡 Operator Tips
- Prioritize 80m and 40m for reliable contacts, especially during evening and night.
- Use FT8, FT4, and other digital modes on higher bands (20m-10m) to maximize weak signal performance.
- Vertical antennas or dipoles at modest height will work well for NVIS and regional work on 80m/40m.
- If chasing DX, monitor grayline times on 40m and 20m for brief openings.
- Contesters: Focus on low bands for rate; check 20m for sporadic short-path openings.
- QRP operators: Stick to digital modes and lower bands for best results.
⏰ Best Operating Times
| Band | Best Times (UTC) | Notes |
|---|---|---|
| 80m | 20:00 – 08:00 | Nighttime is best; good for local/regional |
| 40m | 18:00 – 09:00 | Good evening/night; some morning DX |
| 20m | 14:00 – 18:00 | Fair during day; check grayline |
| 17m | 15:00 – 17:00 | Marginal, short openings possible |
| 15m | 16:00 – 18:00 | Poor, but try digital modes |
| 12m | 16:00 – 18:00 | Mostly closed, rare short openings |
| 10m | 16:00 – 18:00 | Mostly closed, check for sporadic-E |
🌍 DX Opportunities
- Grayline openings on 40m and 20m may allow short DX windows around sunrise/sunset.
- No significant aurora or polar path enhancement expected.
- Sporadic-E on 10m/12m is unlikely but worth checking during afternoon.
- Best DX paths: North-south and trans-equatorial on 40m/20m, especially during local dusk/dawn.
- Watch for short-lived enhancements during solar wind fluctuations, but overall conditions are stable.
📻 Band-by-Band Analysis
| Band | Morning | Day | Evening | Night |
|---|---|---|---|---|
| 80m | 🟡 Good | 🟠 Fair | 🟡 Good | 🟢 Excellent |
| 40m | 🟡 Good | 🟠 Fair | 🟡 Good | 🟢 Excellent |
| 20m | 🟠 Fair | 🟠 Fair | 🟠 Fair | 🟠 Fair |
| 17m | 🔴 Poor | 🔴 Poor | 🔴 Poor | 🔴 Poor |
| 15m | 🔴 Poor | 🔴 Poor | 🔴 Poor | 🔴 Poor |
| 12m | 🔴 Poor | 🔴 Poor | 🔴 Poor | 🔴 Poor |
| 10m | 🔴 Poor | 🔴 Poor | 🔴 Poor | 🔴 Poor |
Analysis:
80m and 40m are the most reliable bands, especially at night when conditions are 🟢 Excellent. 20m offers only 🟠 Fair propagation throughout the day and evening, with limited DX potential. 17m, 15m, 12m, and 10m are largely 🔴 Poor and not recommended except for local contacts or digital mode experimentation. Best band for DX: 40m at night and grayline. Best for regional: 80m/40m evening/night.
📊 Current Solar Activity
Solar Activity Metrics
K-index
Solar Flux (10.7cm)
Sunspot Number
- K-index: 0-1 (very quiet) — Geomagnetic field is calm, favoring stable low-band propagation and minimal auroral disturbance.
- Solar Flux (10.7cm): 89-105 — Below average, limiting maximum usable frequency (MUF) and reducing high-band openings.
- Sunspot Number: 22-60 — Low, indicating weak solar activity and reduced ionization for higher bands.
- Space Weather Overview: No major flares or storms; X-ray flux is low (B2.8), so blackout risk is minimal.
📈 Geomagnetic Conditions
- Recent K-index trend: Stable and low over the past 24 hours (K=0-1)
- Impact: Consistently quiet geomagnetic field means low absorption on lower bands (80m/40m), no auroral enhancement, and minimal polar path disruption. Conditions are steady, with no signs of worsening or geomagnetic storms.
🌟 Space Weather Details
Space Weather Dashboard
X-ray Activity
Solar Wind Speed
Aurora Activity
- X-ray Activity: B2.8 (low) — No risk of HF blackouts or sudden ionospheric disturbances.
- Solar Wind Speed: 360.9 km/s (moderate) — No significant impact; stable geomagnetic conditions expected.
- Particle Environment:
- Electron Flux: 2890 — Slightly elevated but not enough to cause major absorption or fadeouts.
- Proton Flux: 14 — Quiet, no radiation storm risk.
- Aurora Activity: 2 (very low) — No auroral propagation; VHF/UHF aurora paths are closed.
- Helium Line: 102.1 — Indicates low to moderate solar activity, with no upward trend at this time.
📡 Propagation Timeline & Technical Details
Propagation Quality Timeline (24 Hours)
- The past several months show a declining trend in both solar flux (from 138 in June to 105 now) and sunspot numbers (from 93 to 60), which explains the current poor high-band conditions.
- No recent solar events or major disturbances; the environment is stable but not favorable for high-frequency DX.
Solar Activity Trends (6 Months)
🔮 3-Day Forecast
3-Day K-index Forecast
- Expect similar propagation for the next three days: low solar flux and sunspot numbers will keep high bands (20m and up) mostly closed or marginal.
- 80m and 40m will remain the best choices, especially at night and during local grayline.
- No geomagnetic storms or solar events are forecast, so conditions should remain stable.
- No alerts or warnings for HF or VHF operators at this time. Continue to monitor for any sudden solar changes, but plan for low-to-mid band activity.