The solar wind parameters as you can find on the website are derived from the Advanced Composition Explorer (ACE) satellite. This satellite is situated 1/100th of the Sun - Earth distance. The measurements from the ACE satellite reach us in about an hour during normal solar wind speeds. If the speed of the solar wind is high then it takes less time to travel the distance between ACE and Earth. To know exactly how long it takes for the solar wind to travel this distance you look at the graphs on the site. Behind the letters "ETA" which stands for "Estimated Time of Arrival" you will find in minutes, how long it takes for the solar wind to travel between ACE and Earth.
The speed of the solar wind is very important, if the speed is too low it will be harder for geomagnetic disturbances to occur. The solar wind speed normally lies around 300km/sec but increases when a Coronal Hole High Speed Stream (CH HSS) or Coronal Mass Ejection (CME) arrives. During a CME impact, the solar wind speed can jump suddenly to 500, or even more than 1000km/sec. For the lower middle latitudes a decent speed is required and values of around 700km/sec are desirable. This is however not a golden rule and strong geomagnetic storming can also occur during lower speeds if the Interplanetary Magnetic Field values are favourable. On the data plots you can easily see when a CME shock has arrived, the solar wind speed increases with sometimes several 100km/sec. When a shock arrives, it's time to look at the IMF parameters and the magnetometers. Keep in mind that when the shock arrives at the ACE satellite it takes some time (depending on the solar wind speed) to reach Earth. Below you can find a good example of a CME arrival in 2013. This is how the solar wind speed graph could look like during a CME impact. Note the sudden jump in solar wind speed from 400km/sec to almost 700km/sec.
This parameter measures the proton density in the solar wind. The more protons in the solar wind, the more chances we get for an auroral display. The scale, used in the plots, is protons per cubic centimetre or p/cm³. A value above 30p/cm³ is positive for a strong geomagnetic storm but it is no guarantee that we'll get to see any aurora. It often happens that at impact the density is high but then collapses to nearly zero, don't let it fool you. Solar wind speed and the IMF parameters are equally if not more important!
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07:45 Dec 07 2013
|Mittelschwere M1.27 Sonneneruption|
13:12 Nov 23 2013
|Mittelschwere M1.08 Sonneneruption|
02:48 Nov 23 2013
|Mittelschwere M1.18 Sonneneruption|
|Letzte geomagnetische Sturm:||08/12/2013||Kp6 (G2)|