Amateur Radio Propagation Report

Sun Images for Past 72 Hours

Images copyrighted by the SDO/NASA and Helioviewer project

📋 Propagation Summary:
Today’s HF propagation is shaped by a moderate solar flux (125–203) and sunspot numbers just above 100, supporting fair conditions on most bands. However, a K-index of 4 and an A-index of 18 signal elevated geomagnetic activity, which may cause some signal fading and absorption, especially at higher latitudes and on higher bands. Expect fair daytime performance on 20m–10m, with low bands (80m/40m) improving after sunset. Shortwave blackouts are possible due to ongoing C-class X-ray activity. For best results, focus on mid-bands during the day and low bands at night, and watch for brief DX openings on 15m and 12m.

💡 Operator Tips

• Use digital modes (FT8, FT4, RTTY) for improved reliability during geomagnetic disturbances.
• For DX, try 20m and 17m during daylight and 40m or 80m after dark.
• Vertical antennas and low-noise receive setups will help combat geomagnetic noise.
• Monitor grayline times for enhanced long-path and trans-equatorial propagation.
• If contesting, be flexible—switch bands as conditions shift, especially if you notice fading or sudden QSB.

⏰ Best Operating Times

• 80m/40m: Best after sunset through early morning (nighttime)
• 20m/17m: Late morning through late afternoon (daytime)
• 15m/12m/10m: Late morning to early afternoon; watch for brief openings, especially during solar flux peaks
• Grayline: 30–60 minutes around local sunrise/sunset for all bands, especially 40m and 20m

🌍 DX Opportunities

• Grayline propagation is favorable—target east-west paths at sunrise/sunset.
• 20m and 17m offer the most reliable DX windows during the day.
• Short-lived 15m/12m/10m openings possible, especially to equatorial and southern hemisphere regions.
• Aurora activity is low (level 2), so VHF auroral DX is unlikely, but northern ops should monitor for any sudden increases.
• Watch for sporadic-E on 10m and 6m, especially midday.

📻 Band-by-Band Analysis

• Best bands today: 20m, 17m, and 15m for consistent contacts, especially during daylight.
• Low bands (80m/40m) improve after sunset, but remain noisy and less reliable during the day.
• High bands (12m/10m) may open briefly around midday, but are generally poor at night.
• Digital modes will outperform SSB/CW under these conditions, especially on marginal bands.

📊 Current Solar Activity

• K-index: 4 (moderate geomagnetic disturbance; expect increased fading/QSB, especially at high latitudes)
• Solar Flux: 125–203 (supports fair propagation on 20m–10m, but not enough for consistent worldwide 10m openings)
• Sunspot Number: 101–139 (moderate; supports decent HF propagation, especially on mid-bands)
• Space Weather Overview: Elevated X-ray activity (C2.4) increases blackout risk on sunlit paths; solar wind is moderate.

📈 Geomagnetic Conditions

• Recent K-index trend: K-index has risen to 4, indicating unsettled to active geomagnetic conditions over the past 24 hours.
• Impacts: Expect increased absorption and signal fading, especially on polar and high-latitude paths. Conditions may improve if K-index drops in coming hours.

🌟 Space Weather Details

• X-ray Activity: C2.4 (C-class flare level) — increases risk of shortwave blackouts on sunlit side; watch for sudden HF dropouts
• Solar Wind: 424.5 km/s — moderate speed; can enhance geomagnetic activity and cause auroral absorption at high latitudes
• Particle Environment: Electron flux (1660) and proton flux (84) are elevated — can cause increased noise and absorption, especially on higher bands
• Aurora Activity: Level 2 — low; minimal impact on VHF/UHF, but northern ops should monitor for sudden auroral enhancements
• Helium Line: 123.2 — moderate solar activity; no major trend shifts detected

📡 Propagation Timeline & Technical Details

• Solar flux and sunspot numbers have declined from winter peaks but remain at moderate levels, supporting fair HF propagation.
• Recent months show a downward trend in both solar flux and sunspot numbers, but current values are still favorable for mid-band operation.

🔮 3-Day Forecast

• Expect similar conditions over the next 72 hours: moderate solar flux, fair mid-band propagation, and occasional geomagnetic disturbances.
• Monitor K-index: If it drops below 3, expect improved DX on all bands, especially 15m and 12m.
• No major space weather alerts at this time, but stay tuned for sudden X-ray flare or geomagnetic storm warnings.
• Best opportunities: Focus on 20m and 17m during the day, and 40m/80m at night. Use digital modes for best results on marginal bands.