Sun Images for Past 72 Hours
Images copyrighted by the SDO/NASA and Helioviewer project
📋 Propagation Summary: Today’s HF propagation is being shaped by moderate solar activity and a quiet geomagnetic field. The solar flux is at 103, and the sunspot number is 56, both on the lower side compared to recent months, which means higher bands (12m, 10m) will be challenging, while the mid-bands (20m, 17m, 15m) offer the best opportunities, especially during daylight. K-index is low (3), so geomagnetic disturbances are minimal, supporting stable conditions for most HF operations. Expect good openings on 20m throughout the day and evening, with 40m and 80m favoring nighttime local and regional contacts. For DX, timing and mode choice are key—see below for detailed tips.
💡 Operator Tips
- Focus on 20m for reliable DX and intercontinental contacts, especially during daylight and early evening.
- 17m and 15m may yield some DX, but expect only fair conditions—digital modes (FT8, PSK31) will outperform SSB/CW.
- 40m and 80m are best at night for regional and some longer-haul contacts; daytime will be poor.
- 10m and 12m are mostly closed—try only during local noon or if you spot sudden solar upticks.
- Use low-noise antennas and digital modes for marginal bands.
- For contesters: concentrate efforts on 20m and 17m; check 15m for short-lived openings.
- Monitor real-time spots and be ready to switch bands quickly if conditions shift.
⏰ Best Operating Times
| Band | Best Times (UTC) | Notes |
|---|---|---|
| 80m | 20:00–07:00 | Nighttime NVIS/regional; poor daytime |
| 40m | 19:00–08:00 | Nighttime best; fair early morning |
| 20m | 09:00–22:00 | All-day DX, especially midday/evening |
| 17m | 10:00–18:00 | Daytime only, fair DX |
| 15m | 11:00–16:00 | Midday, digital modes preferred |
| 12m | 12:00–15:00 | Brief midday, mostly closed |
| 10m | 12:00–14:00 | Try only at solar noon, low chance |
🌍 DX Opportunities
- Grayline DX: 20m and 17m will be your best bets during local sunrise and sunset—watch for enhanced paths to antipodal regions.
- East-West paths: Most reliable on 20m during daylight; 17m may open briefly.
- North-South paths: 15m may support some short DX, especially to South America or Africa.
- Special events: No major aurora or solar storm alerts, so VHF/UHF DX is unlikely outside of sporadic-E.
- Watch for sudden enhancements: If solar flux rises or K-index drops further, check 15m and 10m for surprise openings.
📻 Band-by-Band Analysis
| Band | Morning | Day | Evening | Night |
|---|---|---|---|---|
| 80m | 🔴 Poor | 🔴 Poor | 🟠 Fair | 🟠 Fair |
| 40m | 🔴 Poor | 🔴 Poor | 🟠 Fair | 🟠 Fair |
| 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 today, offering consistent good conditions from morning through night for both local and DX contacts. 17m and 15m are usable but only fair—digital modes will help here. 40m and 80m are poor during the day but improve to fair at night, making them suitable for evening nets and regional QSOs. 12m and 10m are largely closed or poor all day—skip these unless you see a sudden solar uptick.
📊 Current Solar Activity
Solar Activity Metrics
K-index
Solar Flux (10.7cm)
Sunspot Number
- K-index: 3 — Low geomagnetic activity, means stable HF conditions with little auroral disruption.
- Solar Flux (10.7cm): 103 — Below average, indicates limited ionization for higher bands; favors 20m and lower.
- Sunspot Number: 56 — Low to moderate, supports some HF propagation but not enough for strong high-band openings.
- Space Weather: No major flares or storms reported; X-ray activity is low (B5.4).
📈 Geomagnetic Conditions
- The K-index has remained low and stable over the past 24 hours, indicating quiet geomagnetic conditions.
- No recent spikes or disturbances—good news for HF reliability.
- Expect continued stability unless a sudden solar event occurs.
🌟 Space Weather Details
Space Weather Dashboard
X-ray Activity
Solar Wind Speed
Aurora Activity
- X-ray Activity: B5.4 (low)—no risk of HF blackouts; SFI is steady.
- Solar Wind Speed: 460 km/s—moderate, but not enough to trigger geomagnetic storms.
- Particle Environment: Electron flux is elevated (3280), but proton flux is low (303); minimal impact on HF except possible minor absorption at high latitudes.
- Aurora Activity: Level 1 (very low)—no auroral propagation expected; VHF/UHF aurora paths are closed.
- Helium Line: 102.6—suggests a stable solar environment, no major trend changes.
📡 Propagation Timeline & Technical Details
Propagation Quality Timeline (24 Hours)
- Over the past several months, solar flux and sunspot numbers have declined steadily from their late 2025 peaks (F10.7 from ~160 to 120, SSN from 124 to 79).
- This trend explains the current weakening of high-band (15m, 12m, 10m) propagation and the reliability of 20m.
- No major solar events or geomagnetic storms have occurred recently, supporting stable but subdued HF conditions.
Solar Activity Trends (6 Months)
🔮 3-Day Forecast
3-Day K-index Forecast
- Expect continued quiet geomagnetic conditions and modest solar activity.
- 20m will remain the best all-around band for DX and general contacts.
- 17m and 15m may improve slightly if solar flux rises, but expect only fair conditions.
- 40m and 80m will continue to be night-only bands for reliable contacts.
- No alerts or warnings are in effect; monitor real-time solar data for any sudden changes.
- For VHF/UHF: No aurora or E-skip expected; check 6m for sporadic-E during local afternoons.