Amateur Radio Propagation Report

Sun Images for Past 72 Hours

Images copyrighted by the SDO/NASA and Helioviewer project

📋 Propagation Summary: HF propagation today is moderately challenging, with solar flux at 142 and a sunspot number of 133, supporting fair conditions on most bands. However, a K-index of 4 signals unsettled geomagnetic activity, which may cause some signal fading and increased noise, especially on higher frequencies. Expect the lower bands (80m/40m) to be less productive during the day, while 20m–15m should offer the best overall opportunities, particularly during daylight hours. Operators should anticipate variable propagation, with some regional and DX paths opening briefly, especially around sunrise and sunset. Stay flexible and check band conditions frequently for the best results.

💡 Operator Tips

• Focus on 20m, 17m, and 15m during daylight for the most reliable contacts, especially for DX.
• Use digital modes (FT8, FT4, PSK31) to maximize your chances on marginal bands, as these modes perform well in weak or noisy conditions.
• For local and regional QSOs, try 40m and 80m at night, when noise levels drop and absorption decreases.
• If you’re chasing DX, monitor grayline periods (sunrise/sunset) for enhanced propagation, especially on 20m and 17m.
• Keep an eye on the K-index; if it rises further, expect more QSB (fading) and possible blackouts on higher bands.
• Use directional antennas if available to focus on the best DX paths and reduce noise.

⏰ Best Operating Times

• 80m/40m: Best at night and early morning; avoid daytime due to D-layer absorption.
• 20m/17m/15m: Best from mid-morning to late afternoon; check for DX openings around sunrise and sunset.
• 12m/10m: Fair during midday, but expect shorter openings; monitor for sporadic E or brief enhancements.
• Evening: 20m may remain open for longer-haul DX, especially westward.
• Night: 80m and 40m are your go-to bands for both local and some regional contacts.

🌍 DX Opportunities

• Grayline propagation is promising on 20m and 17m—target sunrise/sunset for long-haul DX, especially toward the opposite hemisphere.
• 15m may open to equatorial and low-latitude regions during peak solar hours.
• 10m/12m: Watch for short, sporadic E-skip openings, especially in the afternoon.
• Aurora activity is low (level 3), so VHF auroral propagation is unlikely, but keep an ear on 6m for any surprises.
• DXpeditions and contests: Focus on 20m–15m during daylight and early evening for best results.

📻 Band-by-Band Analysis

Analysis:

• 20m, 17m, and 15m are the most consistent bands today, offering fair propagation throughout the day and into the evening.
• 80m and 40m are mostly poor during daylight but improve to fair at night—ideal for local/regional QSOs after sunset.
• 12m and 10m may provide brief fair openings during the day, but expect them to close after dark.
• For reliable contacts, stick to the mid-bands (20m–15m) during daylight and lower bands (40m/80m) at night.

📊 Current Solar Activity

• K-index: 4 — Indicates unsettled geomagnetic conditions, which can cause signal fading and increased noise, especially on higher bands.
• Solar Flux (10.7cm): 142 — Supports fair propagation on mid and high HF bands, but not strong enough for robust 10m openings.
• Sunspot Number: 133 — Healthy for this phase of the solar cycle, helping to sustain ionization for HF propagation.
• Space Weather Overview: X-ray flux at B7.8 (low), solar wind speed at 494 km/s (moderate), and aurora level at 3 (quiet).

📈 Geomagnetic Conditions

• The K-index has been fluctuating around 4 over the past 24 hours, indicating unsettled geomagnetic activity.
• No major geomagnetic storms, but conditions are not fully quiet—expect some QSB and possible short-term absorption, especially on polar and high-latitude paths.
• If the K-index rises further, expect more pronounced HF disturbances; if it drops, band conditions should gradually improve.

🌟 Space Weather Details

• X-ray Activity: B7.8 — Low-level X-ray flux; no significant risk of sudden HF blackouts.
• Solar Wind: 494 km/s — Moderate speed, contributing to the unsettled geomagnetic field and some signal variability.
• Particle Environment: Electron flux at 2140 (moderate); proton flux at 23 (quiet). These levels are not likely to cause major propagation disruptions.
• Aurora Activity: Level 3 — Low; auroral propagation on VHF/UHF is unlikely, but northern operators may want to monitor for any sudden increases.
• Helium Line: 129.4 — Indicates moderate solar activity, consistent with fair HF conditions and some variability.

📡 Propagation Timeline & Technical Details

• Over the past several months, solar flux has gradually declined from a high of 160 (Dec 2025) to the current 120 (Apr 2026), and sunspot numbers have also decreased.
• This downward trend means high bands (12m/10m) are less likely to open robustly, while mid-bands (20m/17m/15m) remain the most reliable for both local and DX contacts.
• Historical sunspot and solar flux data show we are past the recent solar maximum, so expect more variable and less predictable high-band openings.

🔮 3-Day Forecast

• Expect continued fair conditions on 20m–15m during daylight, with 80m/40m improving at night.
• K-index may remain unsettled; monitor for any spikes that could further degrade HF propagation.
• 10m/12m: Watch for brief, sporadic E-skip or short DX openings, especially in the afternoon.
• No major space weather alerts, but stay tuned to real-time updates for any sudden changes.
• For best results, operate during daylight on mid-bands and at night on lower bands, using digital modes to maximize contact opportunities.