Ausgestellt: 2018 Dec 18 1230 UTC
Erstellt von NOAA, Space Weather Prediction Center und verarbeitet SpaceWeatherLive.com
Solar activity remained very low under a spotless visible disk. No
Earth-directed CMEs were observed in available coronagraph imagery.
Solar activity is expected to be very low on 18-20 Dec due to the lack
of spotted active regions.
The greater than 2 MeV electron flux was at normal to moderate levels,
and the greater than 10 MeV proton flux continued at background values.
The greater than 2 MeV electron flux is expected to be at normal to
moderate levels on 18-20 Dec, and the greater than 10 MeV proton flux is
expected to remain at background levels.
Solar wind conditions were indicative of weak CH HSS influences. Total
field strength ranged from 3 nT to 8 nT, the Bz component ranged from -5
nT to 6 nT, and the solar wind speed averaged near 435 km/s. The phi
angle was predominantly negative.
Solar wind speed is expected to decrease on 18 Dec due to waning
influences of a negative polarity CH HSS. By 19 Dec, a minor enhancement
in the the solar wind environment is likely, due to weak, grazing
influences of another isolated, negative polarity CH HSS. Weakening
influences of the CH HSS are expected on 20 Dec as it begins rotating
away from a partially geoeffective position.
The geomagnetic field was mostly quiet, with an isolated unsettled
The geomagnetic field is expected to be quiet on 18-19 Dec, with
isolated unsettled periods on 19 Dec, due to the anticipated minor
disturbance in the solar wind environment. A return to quiet conditions
is expected on 20 Dec as any CH HSS influences weaken.