Sun Images for Past 72 Hours
Images copyrighted by the SDO/NASA and Helioviewer project
📋 Propagation Summary: HF propagation today is showing moderate conditions, with solar flux at 113 and a sunspot number of 77—both slightly down from recent months, leading to reduced high-band performance. The K-index is low (2), indicating quiet geomagnetic conditions and minimal disturbance to HF paths. Expect good openings on 20m and 30m throughout the day, while higher bands (15m, 12m, 10m) will be more challenging, especially for long-haul DX. Nighttime conditions on 40m and 80m are favorable for regional and some DX work. Operators should focus on the lower bands for reliable contacts and watch for brief high-band openings during peak solar hours.
💡 Operator Tips:
- Use 20m and 30m during the day for the most consistent DX and intercontinental contacts.
- 40m and 80m will be your best bet for evening and nighttime operations—try these for regional nets and late DX.
- For high bands (17m, 15m, 12m, 10m), monitor for short-lived openings, especially around local noon.
- Digital modes (FT8, FT4, PSK31) can help pull out weak signals, especially on poor bands.
- Keep antennas resonant and low noise—verticals and dipoles will perform well on the lower bands.
- If chasing DX, check grayline times for enhanced propagation, especially on 40m and 20m.
⏰ Best Operating Times
| Band | Best Times (UTC) | Notes |
|---|---|---|
| 80m | 20:00–08:00 | Excellent at night, quiet geomagnetic field |
| 40m | 18:00–10:00 | Strong at night, some day path possible |
| 20m | 10:00–20:00 | Best daytime DX, open most daylight hours |
| 17m | 12:00–18:00 | Occasional openings midday |
| 15m | 13:00–17:00 | Short, sporadic openings possible |
| 12m/10m | 14:00–16:00 | Brief, weak openings if any |
🌍 DX Opportunities
- Best DX paths: 20m and 30m during daylight, especially along the grayline at sunrise/sunset.
- Grayline enhancement: 40m and 20m will benefit most—watch for improved signals at local dawn/dusk.
- Special events: No major space weather alerts, but watch for sudden X-ray spikes (C-class flares) that could cause brief HF blackouts.
- Aurora: Low activity (Aurora index 3), so VHF auroral propagation is unlikely.
📻 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 all-day operation, with consistent good conditions.
- 40m and 80m shine at night and into the early morning, offering good regional and some DX paths.
- 17m and 15m are only fair—expect limited, short openings, mainly midday.
- 12m and 10m are largely closed or poor due to lower solar flux and sunspot numbers; check for sporadic-E but don't expect much.
- For VHF/UHF: No significant auroral or enhanced propagation expected.
📊 Current Solar Activity
Solar Activity Metrics
K-index
Solar Flux (10.7cm)
Sunspot Number
- K-index: 2 (quiet geomagnetic field), minimal disruption to HF propagation.
- Solar Flux (10.7cm): 113 (moderate), supporting good low/mid-band propagation but limiting high-band openings.
- Sunspot Number: 77 (moderate), trending downward from previous months, which reduces high-band performance.
- Space Weather: No major flares, but X-ray flux at C1.0—watch for brief HF absorption events.
📈 Geomagnetic Conditions
- The K-index has remained low and stable over the past 24 hours, indicating quiet geomagnetic conditions.
- No recent geomagnetic storms or disturbances—propagation is stable, especially on lower bands.
- This stability favors nighttime and grayline operation on 40m and 80m.
🌟 Space Weather Details
Space Weather Dashboard
X-ray Activity
Solar Wind Speed
Aurora Activity
- X-ray Activity: C1.0 class—moderate, with a small chance of short HF blackouts, mainly on the sunlit side.
- Solar Wind: 421 km/s—a moderate speed, not likely to trigger geomagnetic storms but worth watching for sudden increases.
- Particle Environment: Electron flux 1910, Proton flux 592—both at moderate levels, not currently causing significant absorption or noise.
- Aurora: Index 3—low, so auroral propagation on VHF/UHF is unlikely.
- Helium Line: 104.8—indicates solar activity is steady but not rising; expect similar conditions for the next day or two.
📡 Propagation Timeline & Technical Details
Propagation Quality Timeline (24 Hours)
- Over the past several months, solar flux and sunspot numbers have declined from spring highs (solar flux 138, SSN 101) to current moderate levels (solar flux 105, SSN 60).
- This downward trend explains the reduced performance on 15m, 12m, and 10m, while 20m and lower bands remain reliable.
Solar Activity Trends (6 Months)
🔮 3-Day Forecast
3-Day K-index Forecast
- Next 3 days: Expect similar propagation with stable geomagnetic conditions and moderate solar activity.
- Best bands: 20m and 40m for DX and regional contacts; 80m for nighttime nets.
- Worst bands: 12m and 10m will remain mostly closed except for possible brief openings.
- No alerts or warnings at this time, but monitor for sudden X-ray increases that could cause short-term HF disruptions.