Viewing archive of Tuesday, 7 September 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Sep 07 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 250 Issued at 2200Z on 07 Sep 2021IA. Analysis of Solar Active Regions and Activity from 06-2100Z to 07-2100Z Solar activity has been at very low levels for the past 24
hours. 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 (08 Sep,
09 Sep, 10 Sep).
IIA. Geophysical Activity Summary 06-2100Z to 07-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 389 km/s at 07/1957Z. Total IMF reached 10
nT at 07/1342Z. The maximum southward component of Bz reached -7 nT at
07/2050Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 1479 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on day one (08 Sep) and quiet levels
on days two and three (09 Sep, 10 Sep).
III. Event Probabilities 08 Sep to 10 Sep
| Class M | 15% | 15% | 15% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 07 Sep 101 Predicted 08 Sep-10 Sep 100/100/100 90 Day Mean 07 Sep 080
V. Geomagnetic A Indices
Observed Afr/Ap 06 Sep 008/007 Estimated Afr/Ap 07 Sep 007/007 Predicted Afr/Ap 08 Sep-10 Sep 008/008-006/005-006/005
VI. Geomagnetic Activity Probabilities 08 Sep to 10 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 25% | 20% | 20% |
| Major-severe storm | 20% | 20% | 20% |
All times in UTC
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