Viewing archive of Sunday, 17 January 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Jan 17 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 17 Issued at 2200Z on 17 Jan 2021IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z Solar activity has been at very low levels for the past 24
hours. There are currently 2 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
with a slight chance for a C-class flare on days one, two, and three (18
Jan, 19 Jan, 20 Jan).
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 316 km/s at 16/2105Z. Total IMF reached 5 nT at
17/0114Z. The maximum southward component of Bz reached -4 nT at
17/2041Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 189 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on days one, two, and three (18 Jan, 19
Jan, 20 Jan).
III. Event Probabilities 18 Jan to 20 Jan
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 17 Jan 077 Predicted 18 Jan-20 Jan 077/077/077 90 Day Mean 17 Jan 085
V. Geomagnetic A Indices
Observed Afr/Ap 16 Jan 002/002 Estimated Afr/Ap 17 Jan 003/003 Predicted Afr/Ap 18 Jan-20 Jan 011/012-013/015-011/012
VI. Geomagnetic Activity Probabilities 18 Jan to 20 Jan
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 40% | 35% |
| Minor storm | 10% | 15% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 15% |
| Minor storm | 25% | 30% | 30% |
| Major-severe storm | 40% | 55% | 45% |
All times in UTC
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