Sun Images for Past 72 Hours
Images copyrighted by the SDO/NASA and Helioviewer project
📋 Propagation Summary: HF propagation today is being shaped by moderate solar activity and slightly unsettled geomagnetic conditions. The solar flux is at 106, with a sunspot number of 44, both trending lower than recent months, which means high bands (12m/10m) are mostly closed, while mid bands (20m/17m/15m) offer the best opportunities, especially during daylight. K-index is currently at 3, indicating some geomagnetic disturbance but not a major storm. Expect good conditions on 20m throughout the day and fair opportunities on 17m/15m, while 80m/40m will be better at night. Focus your efforts on the mid-bands for DX and check grayline times for best results.
💡 Operator Tips:
- Use 20m for reliable daytime DX and regional contacts.
- Try 17m/15m during daylight for possible openings, especially on digital modes (FT8, FT4).
- 80m/40m will perform best after sunset; use these for local and regional QSOs at night.
- With higher bands (12m/10m) mostly closed, focus on CW and digital modes for marginal conditions.
- If chasing DX, work the grayline for enhanced propagation, especially on 20m and 40m.
- Consider using low-noise antennas and preamps on the lower bands to combat increased geomagnetic noise.
⏰ Best Operating Times
| Band | Best Times (UTC) | Notes |
|---|---|---|
| 80m | 21:00 – 07:00 | Best at night, local/regional |
| 40m | 20:00 – 08:00 | Nighttime, good for regional/DX at grayline |
| 20m | 09:00 – 19:00 | Daytime DX, most reliable band today |
| 17m | 11:00 – 17:00 | Daylight, fair for DX, check for openings |
| 15m | 12:00 – 16:00 | Midday, fair, best on digital/CW |
| 12m | 13:00 – 15:00 | Marginal, brief openings possible |
| 10m | 13:00 – 15:00 | Mostly closed, rare short openings possible |
🌍 DX Opportunities
- 20m is the go-to band for daytime DX, especially along the grayline (dawn/dusk).
- 17m/15m may open for short periods, especially toward equatorial and southern paths.
- 40m offers grayline DX at sunrise/sunset—watch for enhanced signals to distant regions.
- Grayline: Peak propagation around local sunrise/sunset on 40m/20m.
- No significant aurora or sporadic-E activity expected for VHF/UHF; focus on HF for DX.
📻 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 |
The 20m band is performing best throughout the day and into the evening, providing the most reliable DX and regional contacts. 17m and 15m offer fair conditions, mainly during daylight hours, with digital and CW modes recommended to maximize contacts. 80m and 40m are poor during the day but improve to fair at night, ideal for local and some regional work. 12m and 10m are mostly closed due to low solar flux and sunspot numbers.
📊 Current Solar Activity
Solar Activity Metrics
K-index
Solar Flux (10.7cm)
Sunspot Number
- K-index: 3 — Slightly unsettled, minor geomagnetic disturbance; some increased noise possible, especially on lower bands.
- Solar Flux (10.7cm): 106 — Below average; limits high-band (12m/10m) openings, favors mid/low bands.
- Sunspot Number: 44 — Low; correlates with weaker high-band propagation and shorter DX windows.
- Space Weather: No major flares or storms; X-ray background at B4.1 (quiet).
📈 Geomagnetic Conditions
- The K-index has been fluctuating around 3, indicating minor geomagnetic unrest but no major storms.
- Recent trends show stable to slightly unsettled conditions, with no sharp spikes—propagation is not severely degraded, but some absorption and noise may be present, especially on polar and high-latitude paths.
- No significant auroral activity is expected.
🌟 Space Weather Details
Space Weather Dashboard
X-ray Activity
Solar Wind Speed
Aurora Activity
- X-ray Activity: B4.1 — Low background; no risk of HF blackouts, normal D-layer absorption.
- Solar Wind Speed: 455.9 km/s — Moderate; may contribute to minor geomagnetic noise, especially at higher latitudes.
- Particle Environment: Electron flux (2220) and proton flux (476) are moderate; not high enough to cause major disruptions, but can slightly increase absorption on lower bands.
- Aurora Activity: 2 — Very low; no VHF/UHF aurora expected, HF not impacted.
- Helium Line: 104.0 — Indicates stable solar activity; no major changes expected in the short term.
📡 Propagation Timeline & Technical Details
Propagation Quality Timeline (24 Hours)
- Over the last 6 months, solar flux has trended downward from a high of 160 in December 2025 to the current 106, with a similar decline in sunspot numbers.
- This trend explains the reduced high-band openings (12m/10m) and the current reliance on 20m/17m for DX.
- Sunspot numbers have also dropped from 124 in December to 44 now, further limiting upper HF propagation.
Solar Activity Trends (6 Months)
🔮 3-Day Forecast
3-Day K-index Forecast
- Expect continued moderate solar activity with no major flares or geomagnetic storms forecast.
- 20m will remain the most reliable DX band, with 17m/15m offering fair but variable conditions.
- 80m/40m will continue to improve at night, especially for local and regional contacts.
- No alerts or warnings; monitor for sudden changes in K-index or solar wind speed for any short-term disruptions.