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 and very quiet geomagnetic conditions. The solar flux is at 102, and the sunspot number is 37, both slightly below recent monthly averages, suggesting somewhat subdued ionospheric support for higher bands. The K-index is at 1 (very quiet), so geomagnetic disturbances are minimal, favoring stable propagation, especially on lower bands. Expect good conditions on 20m and below, with higher bands (15m, 12m, 10m) mostly underperforming except for occasional short openings. For best results, focus on 20m, 40m, and 80m, and watch for enhanced grayline paths around sunrise and sunset.

💡 Operator Tips

• Prioritize 20m and 40m for reliable daytime and evening contacts; these bands are the most consistent under current solar conditions.
• Use digital modes (FT8, PSK31) on higher bands (15m, 12m, 10m) to take advantage of marginal openings.
• Nighttime is prime for 80m and 40m—expect lower noise and improved DX potential.
• Monitor grayline periods for enhanced propagation, especially on 40m and 20m.
• Keep power moderate and antennas efficient; weak-signal modes will outperform SSB/CW on higher bands today.
• VHF/UHF: No significant auroral or sporadic-E activity expected; focus on local FM and repeaters.

⏰ Best Operating Times

• 80m/40m: Best at night and early morning (local time)
• 20m: Good all day, with peaks late morning through afternoon
• 17m/15m: Fair during midday; short openings possible
• 12m/10m: Poor most of the day; check for brief midday or early afternoon openings, especially during solar flux upticks

🌍 DX Opportunities

• Grayline paths (dawn/dusk) on 40m and 20m offer the best shot at DX, especially trans-equatorial and east-west.
• 20m remains the most reliable DX band for intercontinental contacts.
• Low K-index means polar paths are open; try for northern DX if you’re in mid-latitudes.
• Watch for short-lived 15m/17m DX during local noon, but expect limited success.
• No significant aurora or special propagation events expected today.

📻 Band-by-Band Analysis

Analysis:
20m is the most consistent performer throughout the day and evening, making it the go-to band for both local and DX contacts. 40m and 80m shine at night and early morning, offering excellent regional and some DX opportunities. 17m and 15m provide fair conditions, mainly during daylight hours, but expect limited long-haul propagation. 12m and 10m are largely closed due to low solar flux and sunspot numbers—only check these bands if you notice a sudden solar uptick or spot reports of openings.

📊 Current Solar Activity

• K-index: 1 (very quiet)
  • Indicates minimal geomagnetic disturbance; stable HF conditions, especially for polar and high-latitude paths.
• Solar Flux: 102 (moderate/low)
  • Below recent monthly averages; limits higher band openings, but supports 20m and below.
• Sunspot Number: 37
  • Lower than recent months, reflecting the current dip in solar activity and reduced ionization for upper HF bands.
• Space Weather Overview:
  • No major flares or storms. X-ray flux at C1.8 is moderate but not enough to cause HF blackouts.

📈 Geomagnetic Conditions

• Recent K-index trend:
  • Stable and low over the past 24 hours, with no significant spikes. This quiet geomagnetic environment is ideal for HF, especially for DX on 20m and lower bands.
  • No signs of worsening conditions; expect continued stability unless a sudden solar event occurs.

🌟 Space Weather Details

• X-ray Activity:
  • C1.8 level—moderate, but not high enough to cause D-layer absorption or HF blackouts. No current radio blackout risk.
• Solar Wind:
  • Speed at 412.8 km/s—typical background level, not fast enough to trigger geomagnetic storms.
• Particle Environment:
  • Electron flux at 3090 and proton flux at 29—both within normal ranges, so no enhanced absorption or polar cap absorption events expected.
• Aurora Activity:
  • Level 3—quiet, with no auroral propagation expected for VHF/UHF. Northern operators should not expect aurora-related openings.
• Helium Line:
  • 111.1—indicates stable solar conditions with no major uptrends or flare risk.

📡 Propagation Timeline & Technical Details

• Recent solar flux and sunspot trends:
  • Solar flux and sunspot numbers have declined steadily since June, with August values (SFI ~116, SSN ~76) below the spring peak (SFI ~138, SSN ~94). This downward trend explains the weaker performance of 10m/12m and more reliance on 20m/40m for reliable propagation.

🔮 3-Day Forecast

• Expect continued quiet geomagnetic conditions (low K-index) and moderate solar activity. No major solar flares or storms are forecast, so propagation should remain stable. 20m and 40m will continue to be the best bands for both local and DX work, while 15m and above will remain challenging unless a solar uptick occurs. Monitor solar flux and sunspot numbers for any signs of improvement, and take advantage of grayline periods for enhanced DX.