Space Weather Forecast - Discussion

Issued: 2026 Apr 19 0030 UTC
Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center and processed by SpaceWeatherLive.com

Solar activity

24 h Summary

Solar activity was at low levels. Region 4416 (N22W91, Hax/alpha) produced the largest event of the period, a C1.6 flare observed at 18/0704 UTC, as it rotated around the western limb. Region 4419 (N13E01, Eho/beta-gamma) displayed slight decay and consolidation in its trailing spots, with the leader spots separating yet decaying as well. Region 4415 (S18W61, Hsx/alpha) remained unchanged and was unremarkable. From around 18/0730-0823 UTC, an approximately 30 degree long eruptive filament was observed in GONG H-alpha and GOES-19 SUVI imagery lifting off the solar disk. The associated CME off the SE limb was modelled with the resulting output a non Earth impact. No other Earth directed CMEs were observed in coronagraph imagery.

Forecast

Solar activity is likely to be low with a slight chance for M-class (R1-R2, Minor-Moderate) flares on 19-21 Apr, primarily due to the flare potential of Region 4419.

Energetic Particles

24 h Summary

The greater than 2 MeV electron flux at geosynchronous orbit decayed to moderate levels. The greater than 10 MeV proton flux was at background levels.

Forecast

The greater than 2 MeV electron flux is expected to increase back to moderate to high levels on 19-21 Apr. The greater than 10 MeV proton flux is expected to continue at background levels on 18-20 Apr.

Solar Wind

24 h Summary

Solar wind parameters became enhanced at around 17/2300 UTC, as the anticipated CH HSS moved into a geoeffective position. Total field increased to a peak of 17 nT, while the Bz component was mostly negative, seeing a maximum southward deflection to -14 nT. Solar wind speeds varied between approximately 370-400 km/s before gradually increasing to a maximum velocity of ~600 km/s. Phi rotated into a negative orientation just after 17/2300 UTC.

Forecast

Solar wind parameters are expected to remain enhanced on 18 Apr as negative polarity CH HSS influence persists. Solar wind speeds ranging from 600-700 km/s are likely based on recurrent values. Enhanced conditions are expected to continue through 21 Apr.

Geospace

24 h Summary

The geomagnetic field reached G1 (Minor) levels before increasing to G2 (Moderate) levels after 18/0825 UTC.

Forecast

Active to G1 (Minor) geomagnetic storm levels are expected on 19 Apr as negative polarity CH HSS geomagnetic conditions persist. This will be followed by unsettled to active conditions on 20-21 Apr, as HSS effects linger.