Viewing archive of Wednesday, 18 August 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Aug 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 230 Issued at 2200Z on 18 Aug 2021IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z
Solar activity has been at very low levels for the past 24
hours. There are currently 1 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
with a slight chance for a C-class flare on days one, two, and three (19
Aug, 20 Aug, 21 Aug).
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 476 km/s at 17/2108Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 490 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet levels on days one and two (19 Aug, 20 Aug) and quiet to
unsettled levels on day three (21 Aug).
III. Event Probabilities 19 Aug to 21 Aug
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Aug 075 Predicted 19 Aug-21 Aug 075/075/073 90 Day Mean 18 Aug 079
V. Geomagnetic A Indices
Observed Afr/Ap 17 Aug 007/004 Estimated Afr/Ap 18 Aug 005/006 Predicted Afr/Ap 19 Aug-21 Aug 005/005-005/005-008/008
VI. Geomagnetic Activity Probabilities 19 Aug to 21 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 20% |
| Minor storm | 01% | 01% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 20% | 30% |
| Major-severe storm | 15% | 15% | 25% |
All times in UTC
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