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 moderate solar activity with a solar flux of 137 and a sunspot number of 127, supporting generally good conditions on the mid-to-high HF bands. The K-index is at 3, indicating mild geomagnetic unrest, which may cause some fading or noise, especially at higher latitudes. Expect the 20m, 17m, and 15m bands to perform best throughout the day and into the evening, while 80m and 40m will be more reliable at night. 10m and 12m may open for short periods during the day, but will be less reliable overall. Operators should be alert for short-lived DX windows and possible auroral effects at higher latitudes.

💡 Operator Tips

• Focus on 20m, 17m, and 15m for reliable daytime and evening contacts, including DX.
• Use digital modes (FT8, FT4, PSK31) to maximize chances on marginal bands, especially 12m and 10m.
• For low-band operation, target 80m and 40m after sunset for regional and some longer-haul contacts.
• Expect QSB (fading) and increased noise, particularly at higher latitudes and during geomagnetic disturbances.
• If chasing DX, check for grayline openings around local sunrise and sunset on 20m and 17m.
• Portable and QRP operators: Use efficient antennas and consider operating during peak band conditions for best results.

⏰ Best Operating Times

• 80m & 40m: Best at night and early morning
• 20m, 17m, 15m: Good from late morning through evening
• 12m & 10m: Try late morning to mid-afternoon for brief openings
• Grayline (sunrise/sunset): Enhanced long-path DX, especially on 20m and 17m

🌍 DX Opportunities

• 20m and 17m: Most consistent for intercontinental DX, especially during daylight and grayline.
• 15m: Good for trans-equatorial and east-west paths during the day.
• 10m/12m: Watch for short, sporadic E-skip and F-layer openings—check beacons and cluster spots.
• Grayline: Look for enhanced propagation to antipodal regions on 20m/17m at sunrise/sunset.
• Auroral activity: Northern operators may see enhanced VHF/UHF propagation due to moderate aurora (index 5).

📻 Band-by-Band Analysis

• Best bands: 20m, 17m, and 15m are the most reliable for DX and general contacts throughout the day and evening.
• Challenging bands: 12m and 10m may provide brief openings, especially for those using digital modes, but expect limited performance.
• Low bands (80m/40m): Nighttime is best for regional and some DX contacts; daytime absorption is high, making them less effective.

📊 Current Solar Activity

• K-index: 3 (mild geomagnetic activity)—may cause some fading and noise, especially at higher latitudes.
• Solar Flux: 137 (moderate)—supports good propagation on mid/high HF bands.
• Sunspot Number: 127—indicates ongoing solar activity, helping to keep higher bands open.
• Space Weather: C1.2 X-ray flare detected, but no major blackouts expected. Solar wind is elevated at 628.6 km/s.

📈 Geomagnetic Conditions

• The K-index has remained mostly in the 2-3 range over the past 24 hours, showing mild but persistent geomagnetic unrest.
• No major geomagnetic storms, but conditions are not fully quiet—expect some QSB and higher noise, especially at high latitudes.
• If the K-index rises, expect further degradation on high-latitude and polar paths.

🌟 Space Weather Details

• X-ray Activity: C1.2 flare—moderate, not likely to cause major HF blackouts, but brief absorption spikes possible.
• Solar Wind: High at 628.6 km/s—increases the risk of geomagnetic disturbances and auroral activity.
• Particle Environment: Electron flux at 1450—elevated, may cause increased noise and absorption on polar paths.
• Aurora Activity: Index 5—moderate auroral conditions; northern operators may see VHF/UHF aurora propagation.
• Helium Line: 124.3—indicates ongoing solar activity; trend is stable to slightly declining.

📡 Propagation Timeline & Technical Details

• Over the past several months, solar flux and sunspot numbers have declined from their late-2025 peak, but remain at moderate levels.
• This trend supports continued good propagation on mid/high HF bands, but with fewer extended high-band (10m/12m) openings compared to the solar maximum.
• Operators should expect more variable conditions as solar activity gradually decreases.

🔮 3-Day Forecast

• Solar activity is expected to remain moderate; no major flares or storms forecast.
• K-index may fluctuate between 2 and 4—watch for brief geomagnetic disturbances.
• Best bands: 20m, 17m, and 15m will continue to be the most reliable for DX and general contacts.
• 10m and 12m: Occasional brief openings possible, especially during local noon and with digital modes.
• Low bands: 80m/40m will be best at night; daytime absorption remains high.
• VHF/UHF: Watch for auroral propagation in northern latitudes if geomagnetic activity increases.