Viewing archive of Saturday, 31 July 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Jul 31 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 212 Issued at 2200Z on 31 Jul 2021IA. Analysis of Solar Active Regions and Activity from 30-2100Z to 31-2100Z Solar activity has been at very low levels for the past 24
hours. There are currently 0 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
on days one, two, and three (01 Aug, 02 Aug, 03 Aug).
IIA. Geophysical Activity Summary 30-2100Z to 31-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 492 km/s at 30/2102Z. Total IMF reached 6 nT at
30/2338Z. The maximum southward component of Bz reached -2 nT at
31/1817Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 379 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on day one (01 Aug), quiet to unsettled
levels on day two (02 Aug) and quiet levels on day three (03 Aug).
III. Event Probabilities 01 Aug to 03 Aug
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 31 Jul 076 Predicted 01 Aug-03 Aug 074/072/072 90 Day Mean 31 Jul 079
V. Geomagnetic A Indices
Observed Afr/Ap 30 Jul 006/008 Estimated Afr/Ap 31 Jul 008/009 Predicted Afr/Ap 01 Aug-03 Aug 010/012-007/008-006/005
VI. Geomagnetic Activity Probabilities 01 Aug to 03 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 20% | 15% |
| Minor storm | 10% | 05% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 30% | 25% | 20% |
| Major-severe storm | 40% | 25% | 20% |
All times in UTC
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