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 around 116 and sunspot numbers in the mid-70s. Operators can expect good conditions on 20m throughout the day and night, while 80m and 40m offer fair to good operation, especially after sunset. The higher bands (17m, 15m) are only fair, and 12m/10m remain poor due to lower solar flux and recent downward trends in sunspot numbers. Geomagnetic activity is quiet (K-index 0–2), so expect stable propagation with minimal disturbances. For best results, focus on the lower and mid-HF bands, and take advantage of evening and nighttime openings.

💡 Operator Tips

• Prioritize 20m for reliable DX—it’s the most consistent performer today.
• 80m and 40m will be best after sunset; try these for regional and some DX contacts.
• Digital modes (FT8, FT4, RTTY) are recommended on higher bands (15m, 12m, 10m) where SSB/CW may struggle.
• Use directional antennas and low-noise setups to maximize weak-signal work, especially on higher bands.
• For VHF/UHF, expect typical conditions; no enhanced propagation is forecast.
• If you’re chasing DX, watch the grayline—20m and 40m will be your best bets.

⏰ Best Operating Times

• 80m/40m: Evening through early morning (local time) for best NVIS and regional coverage, with some DX possible at night.
• 20m: All day and night—broadest window for both local and long-haul contacts.
• 17m/15m: Late morning to early afternoon—look for short DX openings.
• 12m/10m: Midday only—limited to sporadic E or rare F-layer openings.
• VHF/UHF: No significant openings expected; standard local coverage.

🌍 DX Opportunities

• 20m is the primary DX band today—look for long-path and grayline openings, especially at sunrise and sunset.
• 40m offers nighttime DX, especially along the grayline path.
• 17m/15m may provide short, selective DX to equatorial and southern latitudes during peak daylight.
• **Watch for grayline enhancement_ on 40m and 20m for transcontinental paths.
• No auroral or polar openings expected; VHF/UHF DX is unlikely.

📻 Band-by-Band Analysis

Analysis:

• 20m is the standout performer—good all day and night, ideal for DX and general operation.
• 80m/40m are fair during the day, but good at night—best for local/regional and some DX after sunset.
• 17m/15m are fair—try digital modes for best results, especially midday.
• 12m/10m are poor—skip these unless you spot a rare opening or strong sporadic-E event.

📊 Current Solar Activity

• K-index: 0–2 (very quiet)—minimal geomagnetic disturbance, stable HF conditions.
• Solar Flux: 116 (moderate)—supports good propagation on mid-HF, but not enough for strong 10m/12m openings.
• Sunspot Number: 76 (moderate, but trending downward)—reflects a recent decrease in solar activity.
• Space Weather Overview:
  • No major flares or radio blackouts reported.
  • X-ray flux at B4.4—low, so minimal risk of sudden HF fadeouts.
  • Aurora level at 3—quiet, no auroral propagation expected.

📈 Geomagnetic Conditions

• The K-index has remained very low and stable (0–2) over the past 24 hours.
• No recent geomagnetic storms or disturbances—conditions are improving compared to earlier in the month.
• Expect quiet geomagnetic conditions to continue, supporting stable HF propagation and reducing QSB/fading.

🌟 Space Weather Details

• X-ray Activity: B4.4—very low, so no risk of HF blackouts or major D-layer absorption.
• Solar Wind: 425 km/s—moderate, not high enough to trigger geomagnetic storms.
• Particle Environment:
  • Electron Flux: 1600—slightly elevated, may cause minor polar absorption but not significant for most HF paths.
  • Proton Flux: 11—quiet, no solar proton events.
• Aurora Activity: 3—low, so no auroral propagation on VHF/UHF.
• Helium Line: 112.4—stable, indicating no rapid changes in solar activity.

📡 Propagation Timeline & Technical Details

• Recent Solar Trends:
  Over the past 6 months, solar flux has declined from ~138 (June) to ~116 (August/September), and sunspot numbers have dropped from over 100 to the mid-70s. This downward trend means higher bands (15m/12m/10m) are less reliable, while 20m and lower bands remain robust.

🔮 3-Day Forecast

• Expect similar conditions for the next 3 days: quiet geomagnetic field, moderate solar flux, and stable HF propagation.
• 20m will continue to be the most reliable for DX and general contacts.
• 80m/40m will shine at night; use these for regional nets and ragchews.
• 15m/12m/10m will remain challenging—monitor for any surprise openings, especially during local noon.
• No alerts or warnings are in effect; continue to operate as usual and enjoy the stable conditions!