I have had to disable the solar widget service due to high server loads. It has been a free service for years, but it appears it's going to go down because of its own success.

I will try to find a solution, but can't make any promises. Suggestions are appreciated!

Sorry guys...

Solar Activity of the past 30 days

Solar activity as recorded by NOAA of the past 30 days. Solar flares can be seen especially in the K-index graph as large spikes. Shortwave propagation can be severely affected by flares, causing higher noise levels and weaker signals.

Ai indicates a daily average level for geomagnetic activity. Values range from about 0 to 400. Ai is the average of eight 3-hour Ki values and provides a level of instability in the earth's geomagnetic field. Instability is greatest when both Ai and Ki are high. This can cause HF-signals to fade and paths to open and close with little warning. A high Ki and low Ai indicates an abrupt disturbance in the geomagnetic field, resulting in intense but brief disruptions in HF-propagation. Ai is recorded once a day.

Ki indicates the disturbance in the horizontal component of the earth's magnetic field. Values range from 0 to 9 and are based on 3-hour interval measurements in nT (nano Tesla). The higher the Ki-value, the more static and interference you can expect. Ki-values have more impact at higher latitudes (closer to the poles).

SFI (Solar Flux Index) is the solar radiation measured at 2800 MHz (10.7cm) and gives a good indication of the F-layer ionization. The higher the number, the more the ionization, which gives us nice DX openings on HF-bands. Higher bands are less affected by SFI. Measurements range from about 60 to 300 and are recorded 3 times per day.
The up and down motion is caused by the rotation of the sun which has a cycle of 28 days.

Data on this page is refreshed once a day.

Solar widget

The RigReference Solar Widget gives an indication of the conditions on the various ham bands, for both day and night time.

How to use...

...on WordPress blogs?

If you're using WordPress, you're in luck. We've developed a WordPress solar-plugin which is easy to install and requires zero technical knowlegde. The plugin also allows you to switch between widget layouts from the WordPress admin pages.

...on Drupal sites?

If you're using the Drupal content management system (CMS), please follow our simple step-by-step guide. It describes how to add the widget as a block which allows you to flexibly position the widget on your site.

...on QRZ.com?

For security reasons QRZ.com does not allow the use of JavaScript. A small hack is required for QRZ.com.

...on all other sites?

For all other sites, incorporating the solar widget in your own site requires you copy the code below into your own page -at the location where you want the widget to be displayed.

Wide layout

Tall layout

Please note:
We are constantly looking for ways to improve our widget. Suggestions and remarks are always appreciated! Please use our widget at your own risk. Even though we try very hard, we cannot guarantee it to be correct.


Good conditions
Fair conditions
Poor conditions

The widget is refreshed every hour. The NOAA refreshes their data about every 1 to 3 hours, depending on the measured parameter.

Solar-Terrestrial data

The Solar Widget is based on data from the United States National Oceanic and Atmospheric Administration (NOAA). The raw data is publicly available -in text format- here.

To make any sense of the raw data takes some computational power. After a some trial-and-error and experimenting I came up with an algorithm that I feel represents the HF propagation conditions quite well. So now is the time to go public with my widget.

Please feel free to test and try and contact me with remarks, suggestions, errors or whatever else is relevant.

HF-band conditions (day/night)

These are the values I calculated from the raw NOAA data. There isn't any golden rule for calculation propagation conditions. I've put together an algorithm based on data from different sources. As a rule of thumb, values below 50 are considered poor, between 51 and 79 fair and above 79 good.
Paul Herrman (N0NBH) has a fantastic site if you're into solar and weather data. I've used his info a lot.

Band Day Night
160m Poor (38) Poor (45)
80m Poor (38) Poor (45)
60m Poor (38) Poor (45)
40m Poor (38) Poor (45)
30m Poor (38) Poor (45)
20m Poor (43) Poor (48)
17m Fair (51) Fair (57)
15m Fair (51) Fair (57)
12m Fair (51) Fair (57)
10m Fair (51) Fair (57)

Latest measurement - raw data

This is the latest measurement from NOAA. I use these values to calculate current propagation conditions.

Measurement time (UTC) 2017-02-25 21:10:00
Measurement no. 50013
Ai 6
Ki 1
Solar Flux Index (SFI) 80
Proton flux 14.2
Electron flux 38500
X-Ray X1
S-Noise level S0-1
Geomagnetic field Very quiet

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