Sun Images for Past 72 Hours

Images copyrighted by the SDO/NASA and Helioviewer project
๐ Propagation Summary: HF propagation today is being shaped by moderate solar activity and elevated geomagnetic disturbance. The solar flux is at 128, which supports decent daytime propagation on the higher bands, but the K-index at 4 and A-index at 24 indicate unsettled geomagnetic conditions that may cause fading and absorption, especially at higher latitudes. Sunspot numbers have dropped compared to previous months, so expect generally fair conditions on most bands, with low bands (80m/40m) performing better at night and high bands (12m/10m) being less reliable. Operators should focus on 20mโ15m for the most consistent results. Watch for short-lived DX windows, especially around grayline.
๐ก Operator Tips:
- Use digital modes (FT8, FT4, PSK31) for improved reliability during unsettled conditions.
- 20m and 17m are your best bets for daytime DX; try 40m and 80m after sunset.
- Employ low-noise antennas and good grounding to combat increased QRN from geomagnetic activity.
- Monitor grayline periods for enhanced propagation, especially on 40m and 20m.
- If contesting or chasing DX, check spotting networks for brief high-band openings.
โฐ Best Operating Times
- 80m/40m: Best after local sunset through sunrise; avoid daytime.
- 20m/17m/15m: Most reliable from late morning through late afternoon.
- 12m/10m: Watch for brief midday openings, but expect generally fair to poor conditions.
- Grayline (dawn/dusk): Enhanced long-path and trans-equatorial propagation, especially on 40m and 20m.
๐ DX Opportunities
- Grayline: Look for improved east-west DX paths on 40m and 20m during local sunrise and sunset.
- Auroral Zone: Elevated aurora index (2) may open VHF paths in far northern regions, but also cause HF absorption.
- Equatorial Paths: 15m and 17m may support trans-equatorial contacts midday.
- Short Openings: Be alert for sporadic-E or brief F-layer openings on 10m/12m, especially during solar wind spikes.
๐ป Band-by-Band Analysis
| Band | Morning | Day | Evening | Night |
|---|---|---|---|---|
| 80m | ๐ Fair | ๐ด Poor | ๐ Fair | ๐ก Good |
| 40m | ๐ Fair | ๐ด Poor | ๐ Fair | ๐ก Good |
| 20m | ๐ก Good | ๐ก Good | ๐ Fair | ๐ Fair |
| 17m | ๐ก Good | ๐ก Good | ๐ Fair | ๐ Fair |
| 15m | ๐ก Good | ๐ก Good | ๐ Fair | ๐ Fair |
| 12m | ๐ Fair | ๐ Fair | ๐ด Poor | ๐ด Poor |
| 10m | ๐ Fair | ๐ Fair | ๐ด Poor | ๐ด Poor |
The 20m, 17m, and 15m bands are currently the most reliable for daytime operation, offering good propagation for both local and DX contacts. 80m and 40m are fair to good at night, making them ideal for evening ragchews and DX. 12m and 10m may open briefly during midday but are generally fair or poor due to declining solar activity and increased geomagnetic disturbance.
๐ Current Solar Activity
Solar Activity Metrics
K-index
Solar Flux (10.7cm)
Sunspot Number
- K-index (4): Indicates active geomagnetic conditionsโexpect increased fading, especially at higher latitudes.
- Solar Flux (128): Supports fair to good propagation on 20mโ15m; 10m/12m less reliable.
- Sunspot Number (72): Moderate, but part of a declining trendโhigh bands less robust than earlier in the year.
- Space Weather: X-ray flux at C1.1 (minor flare activity); solar wind is very high at 739.5 km/s, contributing to geomagnetic instability.
๐ Geomagnetic Conditions
Recent K-index values have been elevated, trending around 4 over the past 24 hours. This indicates a period of increased geomagnetic disturbance, likely from a recent solar wind stream or minor CME. Conditions are currently unsettled and may cause absorption and fading, especially on polar and high-latitude paths. Monitor for any further increases, which could lead to short HF blackouts or auroral propagation.
๐ Space Weather Details
Space Weather Dashboard
X-ray Activity
Solar Wind Speed
Aurora Activity
- X-ray Activity: C1.1 level means minor solar flare activityโpossible brief HF blackouts on sunlit paths.
- Solar Wind: Very high at 739.5 km/s, increasing risk of auroral absorption and geomagnetic disturbance.
- Particle Environment: Electron flux at 2090 (elevated), proton flux at 16โmay cause minor disturbances, especially for polar paths.
- Aurora Activity: Index at 2โnorthern operators may see some auroral flutter on HF and possible VHF aurora on 6m/2m.
- Helium Line (121.6): Stable, indicating no major solar trend shifts currently.
๐ก Propagation Timeline & Technical Details
Propagation Quality Timeline (24 Hours)
Recent months show a steady decline in solar flux and sunspot numbers since mid-2026, with solar flux dropping from 138 in June to 108 in October. This trend explains the reduced reliability of high bands (12m/10m) and increased dependence on 20mโ15m for DX.
Solar Activity Trends (6 Months)
๐ฎ 3-Day Forecast