An X1.5 flare has occurred with a peak time 11:44 UTC on May 11, produced by NOAA AR 3664. Moderately disturbed radio communications have been observed related to this flaring activity.

A class M8.8 solar X-ray flare occurred on 2024/05/11 with peak time 15:25UT

A halo or partial-halo CME was detected with the following characteristics: t0 | dt0| pa | da | v | dv | minv| maxv| 2024-05-11T01:36:07.514 | 3.0 | 286 | 154 | 893 | 474 | 406 | 1954 t0: onset time, earliest indication of liftoff dt0: duration of liftoff (hours) pa: principal angle, counterclockwise from North (degrees) da: angular width of the CME (degrees), v: median velocity (km/s) dv: variation (1 sigma) of velocity over the width of the CME mindv: lowest velocity detected within the CME maxdv: highest velocity detected within the CME

The solar flaring activity was at high levels with several M-class flares and two X-class flares during the last 24 hours. The strongest reported flare was GOES X5.8 flare which peaked at 01:23 UTC on May 11, produced by NOAA Active Region (AR) 3664. During the flare, source region (AR 3664) of the flare had beta-gamma-delta configuration of its photospheric magnetic field. The solar flaring activity is expected to be at high levels over the next 24 hours possibly with M-class flares and chance for X-class flare. A bright partial halo coronal mass ejection (CME) was first observed on SOHO/LASCO-C2 images around 01:36 UTC on May 11. This CME is associated with an X5.8 flare, which peaked at 01:23 UTC, produced by NOAA AR 3664. Associated type II and type IV radio emissions were detected at 01:13 UTC and 01:24 UTC, respectively. This CME has a speed of about 1050 km/s. The corresponding ICME is expected to impact the Earth on the evening of May 12. The greater than 10 MeV GOES proton flux is currently above the 10 pfu threshold level. It was shortly, from 01:10 UTC to 02:10 UTC on May 11, below the 10 pfu threshold level. It started to increase again from 02:10 UTC and it continues to increase. Both the greater than 50 MeV GOES proton flux and the greater than 100 MeV GOES proton flux began to increase from 01:40 UTC on May 11. The greater than 50 MeV GOES proton flux crossed the 10 pfu threshold level at 05:50 UTC and it is increasing. The greater than 100 MeV GOES proton flux is just below the 10 pfu threshold level and it is increasing. The proton flux is expected to remain elevated as more particle events are possible in the coming days, with possibility for a major proton event (greater than 100MeV crossing the 100 pfu threshold level). The greater than 2 MeV electron flux, as measured by the GOES-16 satellite, was below the threshold level over the past 24 hours and is expected to remain so in the coming 24 hours. The 24h electron fluence is presently at normal level and we may expect moderate level in the next 24 hours.

Geomagnetic conditions reached severe to extreme storm levels (NOAA Kp and K BEL 8 to 9) globally and locally starting from 15:00 UTC and 19:00 UTC on May 11, respectively. This was due to the arrival of three interplanetary coronal mass ejections (ICMEs) associated to CMEs observed on May 08-09 (produced by NOAA AR 3664). Currently, both globally and locally, we have extreme storm levels. We expect severe to extreme storm levels in the coming days due to the possible arrival of few more ICMEs associated to CMEs observed on May 09-10 (produced by NOAA AR 3664). High speed streams, originating from two coronal holes that crossed the central meridian on May 08, are also expected to impact the Earth in the coming days. In the last 24 hours, the Earth came under the influence of multiple interplanetary coronal mass ejections (ICMEs) arrival. A shock was detected in the solar wind data around 16:42 UTC on May 10. The interplanetary magnetic field jumped from 4 nT to 44 nT, the solar wind speed jumped from 460 km/s to 700 km/s and the solar wind density at the shock increased from 5/cm3 to 30/cm3. The shock is related to the first ICME arrival, which is associated to one of the CMEs that were observed on May 08. Around 21:39 UT on May 10, another shock-like structure was observed possibly related to arrival of second ICME. We were expecting three ICME arrivals related to CMEs observed on May 08-09, and possibly all ICMEs have arrived. The solar wind speed increased as high as 800 km/s. The North-South component (Bz) ranged between -50 nT and 62 nT. The interplanetary magnetic field ranged from 3 nT to 73 nT. Highly enhanced solar wind parameters associated with arrival of few more ICMEs (CMEs observed on May 09-10, produced by NOAA AR 3664) and high speed streams originating from two coronal holes, which crossed the central meridian on May 08, are expected in the next 24 hours.