Viewing archive of Saturday, 20 January 2018
Solar activity report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 2018 Jan 20 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 20 Issued at 2200Z on 20 Jan 2018IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z Solar activity has been at very low levels for the past 24
hours. There are currently 0 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
on days one, two, and three (21 Jan, 22 Jan, 23 Jan).
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 454 km/s at 20/1901Z. Total IMF reached 10
nT at 20/0647Z. The maximum southward component of Bz reached -8 nT at
20/0559Z.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on day one (21 Jan) and quiet to
unsettled levels on days two and three (22 Jan, 23 Jan).
III. Event Probabilities 21 Jan to 23 Jan
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 20 Jan 070 Predicted 21 Jan-23 Jan 070/070/070 90 Day Mean 20 Jan 072
V. Geomagnetic A Indices
Observed Afr/Ap 19 Jan 006/005 Estimated Afr/Ap 20 Jan 009/012 Predicted Afr/Ap 21 Jan-23 Jan 011/012-008/010-010/010
VI. Geomagnetic Activity Probabilities 21 Jan to 23 Jan
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 20% | 20% |
| Minor storm | 10% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 20% | 20% |
| Minor storm | 30% | 25% | 25% |
| Major-severe storm | 35% | 25% | 20% |
All times in UTC
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