Viewing archive of Saturday, 4 September 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Sep 04 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 247 Issued at 2200Z on 04 Sep 2021IA. Analysis of Solar Active Regions and Activity from 03-2100Z to 04-2100Z Solar activity has been at very low levels for the past 24
hours. There are currently 5 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
with a chance for a C-class flares on days one, two, and three (05 Sep,
06 Sep, 07 Sep).
IIA. Geophysical Activity Summary 03-2100Z to 04-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 447 km/s at 04/0817Z. Total IMF reached 6 nT at
04/0200Z. The maximum southward component of Bz reached -5 nT at
03/2140Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 966 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on days one and two (05 Sep, 06 Sep)
and quiet levels on day three (07 Sep).
III. Event Probabilities 05 Sep to 07 Sep
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 04 Sep 087 Predicted 05 Sep-07 Sep 086/084/082 90 Day Mean 04 Sep 080
V. Geomagnetic A Indices
Observed Afr/Ap 03 Sep 006/008 Estimated Afr/Ap 04 Sep 006/005 Predicted Afr/Ap 05 Sep-07 Sep 008/010-008/008-006/005
VI. Geomagnetic Activity Probabilities 05 Sep to 07 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 20% | 10% |
| Minor storm | 10% | 05% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 25% | 25% | 20% |
| Major-severe storm | 35% | 25% | 20% |
All times in UTC
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