A Coronal Mass Ejections (CME) seen in SOHO/LASCO images as launched at 15 May 08:27 UTC is believed to be two separate CME originating from NOAA Active Regions (AR) 3670 and 3664. The first one is expected to arrive at Earth's environment on the second half on 17 May. The second is expected to deliver at most a glancing blow earlier the same day. A CME that registered in SOHO/LASCO images as emitted at 14 May 18:36 UTC is associated with the X8.7 flare of 14 May and is expected to deliver a glancing blow during the second half of 17 May. Due to the expected arrival of the CME of 15 May at approximately the same time, this glancing blow might not be apparent.

A class X2.9 solar X-ray flare occurred on 2024/05/15 with peak time 14:38UT

A halo or partial-halo CME was detected with the following characteristics: t0 | dt0| pa | da | v | dv | minv| maxv| 2024-05-15T21:12:12.069 | 3.0 | 310 | 150 | 763 | 439 | 112 | 1838 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

Solar flaring activity was low during the past 24 hours. The brightest flare was a C8 emitted today at 01:46 UTC by NOAA Active Region (AR) 3679 (magnetic configuration Beta-Gamma). The same AR produced most of the C-class flaring activity of the past 24 hours, namely another four flares. The large NOAA AR 3685 (magnetic configuration Beta-Gamma) produced two C-class flares and NOAA AR 3674 (magnetic configuration Beta, Catania sunspot group 3) one. For the next 24 hours, NOAA AR 3679 is expected to continue to produce C-class flares with a chance of an M-class flare. NOAA AR 3685 is expected to increase its activity, likely produce M-class flares, with a small chance of an X-class flare. No Earth-directed Coronal Mass Ejections (CME) were observed in the last 24 hours. The greater than 10 MeV proton flux, as measured by the GOES-18 satellite, dropped below the 10 pfu threshold level during the last 24 hours. It is likely that it will continue its gradual drop in the next 24 hours, however, there is a small chance of a new proton event and an increase in flux above the alert level. The greater than 2 MeV electron flux, as measured by the GOES-16 satellite, was at very low levels during the last 24 hours and is expected to to remain so during the next 24 hours. The 24h electron fluence was at low levels during the past 24 hours and is expected to remain at these levels for the following 24 hours.

In the past 24 hours the global geomagnetic conditions dropped from minor storm levels (NOAA Kp 5- between 12:00-15:00 UTC) to quiet levels (as low as NOAA Kp 1+). During the same period the local conditions dropped from the active level (K BEL 4 between 12:00-18:00 UTC), to the quite level (K BEL 2). The expected arrival of a Coronal Mass Ejection (CME) is predicted to increase the geomagnetic levels to active or minor storm in the next 24 hours. The Solar Wind conditions were gradually returning to a slow wind regime, as the effects from the arrival of the Coronal Mass Ejection (CME) yesterday are waning. The SW speed decreased from 470 km/s to 300 km/s and the total interplanetary magnetic field (Bt) dropped from 12 nT to 1 nT. The North-South magnetic component (Bz) fluctuated between -12 and 10 nT when still under the influence of the CME. The interplanetary magnetic field phi angle was directed away and towards the Sun in almost equal measure during the past 24 hours. A CME is expected to arrive in the next 24 hours and cause a significant effect.