SIDC URSIGRAM 40518
SIDC SOLAR BULLETIN 18 May 2004, 1230UT
SIDC FORECAST (valid from 1230UT, 18 May 2004 until 20 May 2004)
SOLAR FLARES  : Eruptive (C-class flares expected, probability >= 50%)
GEOMAGNETISM  : Active conditions expected (A>=20 or K=4)
SOLAR PROTONS : Quiet
PREDICTIONS FOR 18 May 2004  10CM FLUX: 112 / AP: 011
PREDICTIONS FOR 19 May 2004  10CM FLUX: 108 / AP: 017
PREDICTIONS FOR 20 May 2004  10CM FLUX: 106 / AP: 014
COMMENT: Two C-class flares happened today, the first one, a C2.6 came from
sunspot group 28 (NOAA 0612) which became active since yesterday, May 17. Former
sunspot group 31 (NOAA 0614) turns over the westlimb. In ACE-data, the solar
wind speed went from 300 km/s to 360 km/s in a time period of 2 hours. The B_z
component of the IMF went down to values of -5nT at the time of the beginning of
the increase of the solar wind speed. From that moment, it was predominantly
negative. Dourbes measured a local K-index of 3 for the period 6:00UT 9:00UT.
For tomorrow, active geomagnetic periods can be possible as a small coronal hole
will be at a geoeffective position.




SOLAR INDICES FOR 17 May 2004
SUNSPOT INDEX       : 104
10CM SOLAR FLUX     : 111
AK CHAMBON LA FORET : 008
AK WINGST           : ///
ESTIMATED AP        : 006

NOTICEABLE EVENTS SUMMARY
DAY BEGIN MAX  END  LOC   XRAY OP 10CM     TYPE          Catania NOAA NOTE
NONE
END
BT