Viewing archive of Tuesday, 28 December 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Dec 28 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 362 Issued at 2200Z on 28 Dec 2021IA. Analysis of Solar Active Regions and Activity from 27-2100Z to 28-2100Z Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M1 event observed at
28/0401Z from Region 2918 (N21W26). There are currently 5 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (29 Dec, 30 Dec,
31 Dec).
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 551 km/s at 28/1500Z. Total IMF reached 10
nT at 28/0125Z. The maximum southward component of Bz reached -8 nT at
28/0330Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 284 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on day one (29 Dec) and quiet to
unsettled levels on days two and three (30 Dec, 31 Dec).
III. Event Probabilities 29 Dec to 31 Dec
| Class M | 25% | 25% | 25% |
| Class X | 05% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 28 Dec 121 Predicted 29 Dec-31 Dec 122/122/120 90 Day Mean 28 Dec 093
V. Geomagnetic A Indices
Observed Afr/Ap 27 Dec 008/009 Estimated Afr/Ap 28 Dec 009/010 Predicted Afr/Ap 29 Dec-31 Dec 013/014-007/010-007/008
VI. Geomagnetic Activity Probabilities 29 Dec to 31 Dec
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 25% | 20% |
| Minor storm | 15% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 20% |
| Minor storm | 30% | 30% | 30% |
| Major-severe storm | 45% | 30% | 25% |
All times in UTC
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