Solar Activity

» 24 hr Summary: Solar activity reached moderate levels. The largest event of the past 24 hours was the decay phase of an M4.4 flare at 18/2350 UTC from a source just beyond the SE limb. Region 4065 (S30E36, Dso/beta) and Region 4063 (N05W35, Bxo/beta) were the only regions to exhibit growth. Only minor changes were observed in the remaining spotted active regions. No Earth-directed CMEs were observed in available coronagraph imagery.

» Forecast: Solar activity is expected to be low with a chance of M-class flares (R1-R2, Minor-Moderate) over 20-22 Apr.

Energetic Particles

» 24 hr Summary: The greater than 2 MeV electron flux was at normal to moderate levels and the greater than 10 MeV proton flux was at background levels.

» Forecast: The greater than 2 MeV electron flux is like to be at normal to moderate levels over 20-22 Apr. The greater than 10 MeV proton flux is expected to continue at background levels.

Solar Wind

» 24 hr Summary: Solar wind parameters were mildly enhanced. Total magnetic field strength was between 4-9 nT. The Bz component was primarily oriented southward, with a maximum southward deflection of -8 nT at 19/2030 UTC. Solar wind speeds were between ~350-400 km/s. Phi angle was predominantly negative.

» Forecast: Solar wind parameters are likely to continue at or near background levels over 20-21 Apr. An enhancement is likely on 22 Apr due to the anticipated onset of a recurrent positive polarity CH HSS.

Geospace

» 24 hr Summary: The geomagnetic field was at unsettled to active levels.

» Forecast: The geomagnetic field is expected to range from quiet to active levels on 20-21 Apr. G1-G2 (Minor-Moderate) geomagnetic storm levels are likely on 22 Apr due to the anticipated onset of a positive polarity CH HSS.


Prepared by:
The U.S. Dept. of Commerce, NOAA, SWPC