Viewing archive of Saturday, 28 August 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Aug 28 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 240 Issued at 2200Z on 28 Aug 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 M4 event observed at
28/0611Z from Region 2860 (S29W10). There are currently 4 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 Aug, 30 Aug,
31 Aug).
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
The geomagnetic
field has been at quiet to minor storm levels for the past 24 hours.
Solar wind speed reached a peak of 389 km/s at 28/1718Z. Total IMF
reached 14 nT at 27/2100Z. The maximum southward component of Bz reached
-12 nT at 27/2131Z. Electrons greater than 2 MeV at geosynchronous
orbit reached a peak level of 10655 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to minor storm levels on days one and two (29 Aug, 30
Aug) and quiet levels on day three (31 Aug).
III. Event Probabilities 29 Aug to 31 Aug
| Class M | 30% | 30% | 30% |
| Class X | 05% | 05% | 05% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 28 Aug 090 Predicted 29 Aug-31 Aug 090/090/090 90 Day Mean 28 Aug 079
V. Geomagnetic A Indices
Observed Afr/Ap 27 Aug 019/021 Estimated Afr/Ap 28 Aug 013/016 Predicted Afr/Ap 29 Aug-31 Aug 011/018-022/025-007/008
VI. Geomagnetic Activity Probabilities 29 Aug to 31 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 30% | 20% |
| Minor storm | 35% | 40% | 05% |
| Major-severe storm | 20% | 25% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 05% | 05% | 15% |
| Minor storm | 20% | 15% | 30% |
| Major-severe storm | 75% | 80% | 30% |
All times in UTC
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