SIDC Ursigram

3-day Forecast of Solar and Geomagnetic Activity: Latest Issue and Archive

INFO FROM SIDC - RWC BELGIUM 2017 May 28 14:15:30

Over the past 24 hours solar activity has increased. There have been four
B-flares flares originated at NOAA AR 2659 (McIntosh:Dai; Mag.Type:Beta).
The biggest flare B9.2 peaked yesterday (27-Mar-2017) at 18:30 UT. No
Earth-directed CMEs have been detected over the past 24 hours. Solar
electron and proton fluxes have remained at background levels over the past
24 hours. NOAA AR 2659 is expected to produce more B-class and C-class
flares over the next 24 hours.

Solar wind speed was fluctuating around 300 km/s (DSCOVR) until 14:50 UT
yesterday when a small shock was observed in the solar wind due to the
arrival of the 23-May-2017 coronal mass ejection. Initially, solar wind
speed abruptly increased from 303 km/s to 385 km/s and density increased
from 4.6 to 70p/cm3.

The Total Interplanetary Magnetic Field (IMF) strength Bt jumped from 2.5
to 10 nT, while the Bz component jumped to -8.5 nT. Later on yesterday, Bt
reached a maximum of 22.30 nT at 22:30 UT and Bz component reached -20.5 nT
value. Then Bt started to decrease gradually (till 16.5 nT), while Bz
slowly returned to low values (-3.5 nT) being strongly negative. Solar wind
speed is currently (28-May-2017 October, 12:30 UT) below 400 km/s.

Kp index reached moderate storm levels (Kp=6) from 21 UT (2017-05-27) to 03
UT (2017-05-28, today). During 03-06 UT, today Kp reached major storm
levels (Kp=7) and during 06-12 UT again moderate and minor storm levels
(Kp=6, Kp=5). Local K index at Dourbes was mostly at minor to major
storming levels (K=5,4,5,6,7,5) from 21 UT (2017-05-27) to 12 UT
(2017-05-28, today).

Total IMF strength is expected to remain at high levels tomorrow, and Bz
component is not expected to become strongly negative. Solar Wind speed is
expected to remain below 400 km/s. Therefore geomagnetic environment is
expected to remain most probably at active conditions (Kp=4) for the next
two days. However, isolated minor storming episodes (Kp=5) are still

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2017 May 28 0919 UTC
As expected, the arrival of 23-May-2017 coronal mass ejection yesterday [more]

2017 May 15 1231 UTC
END OF ALL QUIET ALERT ...................... The SIDC [more]

2014 Sep 10 1926 UTC
A class X1.6 solar X-ray flare occurred on 2014/09/10 with peak time 17:45 [more]

2014 Sep 07 1337 UTC
The latest halo CME alert generated by the CACTus software package: 025|2014/09/06 [more]

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