Viewing archive of Friday, 27 August 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Aug 27 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 239 Issued at 2200Z on 27 Aug 2021IA. Analysis of Solar Active Regions and Activity from 26-2100Z to 27-2100Z Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C3 event observed at
26/2322Z from Region 2860 (S30E14). There are currently 4 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is likely to be low with a
slight chance for an M-class flare on days one, two, and three (28 Aug,
29 Aug, 30 Aug).
IIA. Geophysical Activity Summary 26-2100Z to 27-2100Z
The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 525 km/s at 27/1906Z. Total IMF reached 16
nT at 27/1315Z. The maximum southward component of Bz reached -15 nT at
27/1847Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 161 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to minor storm levels on days one, two, and three (28
Aug, 29 Aug, 30 Aug).
III. Event Probabilities 28 Aug to 30 Aug
| Class M | 15% | 15% | 15% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 27 Aug 090 Predicted 28 Aug-30 Aug 090/090/090 90 Day Mean 27 Aug 079
V. Geomagnetic A Indices
Observed Afr/Ap 26 Aug 006/006 Estimated Afr/Ap 27 Aug 018/022 Predicted Afr/Ap 28 Aug-30 Aug 012/015-011/018-022/025
VI. Geomagnetic Activity Probabilities 28 Aug to 30 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 40% | 35% | 30% |
| Minor storm | 25% | 35% | 40% |
| Major-severe storm | 05% | 20% | 25% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 05% | 05% |
| Minor storm | 20% | 20% | 15% |
| Major-severe storm | 65% | 75% | 80% |
All times in UTC
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