Solar Flux
A useful broad indicator of solar activity affecting HF. Rising flux often improves the odds of higher-frequency HF bands opening, but path, season, time of day, and geomagnetic activity still matter.
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WC4DC · HF PROPAGATION CENTER
Know what the bands are doing before you call CQ.
Use current solar and geomagnetic conditions, day/night band outlooks, and recent trends to decide where to listen, what to try, and what changed when a band suddenly opens or closes.
1 · LOOKCheck the band outlookCompare day and night.
2 · LISTENVerify on the airPropagation reports are guidance, not a guarantee.
3 · LEARNWatch the trendConnect changing solar numbers to what you actually hear.
Right Now
Current HF outlook
This is the latest propagation snapshot stored by WC4DC. Start with the band table, then use the solar metrics to understand what may be driving the outlook.
Solar Conditions & Ham Radio Propagation
Simplified current conditions from the latest stored HamQSL / N0NBH snapshot.
Fetched: 2026-08-26 04:26:17 UTC
Feed says: 26 Aug 2026 0426 GMT
Band Conditions
| Band Group | Day | Night |
|---|---|---|
| 80m-40m | Fair | Good |
| 30m-20m | Good | Good |
| 17m-15m | Good | Good |
| 12m-10m | Fair | Poor |
Solar Conditions
Sunspot Number
83
Current sunspot count
Solar Flux
132
Higher often helps upper HF bands
A-Index
4
Average geomagnetic activity
Kp-Index
N/A
Lower is generally better
X-Ray
B6.8
Solar X-ray intensity class
Solar Wind
315.6
km/s from feed
Noise Floor
S0-S1
Reported signal noise
Geomagnetic Field
INACTIVE
Text summary from feed
304 Å
120.4
Solar radiation at 30.4nm
Proton Flux
48
Charged proton density
Electron Flux
5310
Charged electron density
MUF
NoRpt
Maximum usable frequency
Source data: N0NBH.
Plugin created by: KQ4DLB
Make Sense of the Numbers
What should I pay attention to?
A-Index
A daily-scale measure of geomagnetic disturbance. Lower values generally mean calmer conditions; higher values can make HF paths noisier or less reliable.
K / Kp Index
A shorter-term measure of geomagnetic activity. A rapid increase can explain why conditions deteriorate even when solar flux still looks promising.
X-Ray Activity
Solar flares can cause sudden ionospheric disturbances, especially on sunlit paths. Treat the X-ray class as context when a band changes abruptly.
Propagation is probabilistic. A “Poor” outlook does not mean no contacts are possible, and a “Good” outlook does not guarantee a path. The radio is still the final test.
Recent Movement
Watch the trend, not just one reading.
These charts use the history WC4DC is already storing. They can help explain whether today is part of a broader change or just a short-lived spike.
Solar Flux Trend
A-Index Trend
Sunspots Trend
TURN CONDITIONS INTO CONTACTS
Pick a band, listen first, then get on the air.
Use propagation as one input alongside the band plan, local noise, your antenna, and what you can actually hear. Experimenting is part of amateur radio.
