Viewing archive of Thursday, 22 April 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Apr 22 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 112 Issued at 2200Z on 22 Apr 2021IA. Analysis of Solar Active Regions and Activity from 21-2100Z to 22-2100Z
Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C4 event observed at
22/0921Z from Region 2817 (N18W88). There are currently 3 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 (23 Apr,
24 Apr, 25 Apr).
IIA. Geophysical Activity Summary 21-2100Z to 22-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 489 km/s at 21/2148Z. Electrons greater than 2 MeV at
geosynchronous orbit reached a peak level of 15548 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on day one (23 Apr), quiet to unsettled
levels on day two (24 Apr) and quiet to major storm levels on day three
(25 Apr).
III. Event Probabilities 23 Apr to 25 Apr
| Class M | 10% | 10% | 10% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 22 Apr 084 Predicted 23 Apr-25 Apr 084/084/082 90 Day Mean 22 Apr 076
V. Geomagnetic A Indices
Observed Afr/Ap 21 Apr 007/007 Estimated Afr/Ap 22 Apr 005/005 Predicted Afr/Ap 23 Apr-25 Apr 009/010-008/008-019/025
VI. Geomagnetic Activity Probabilities 23 Apr to 25 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 40% | 30% | 25% |
| Minor storm | 15% | 10% | 40% |
| Major-severe storm | 01% | 01% | 15% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 15% | 05% |
| Minor storm | 25% | 25% | 20% |
| Major-severe storm | 50% | 40% | 70% |
All times in UTC
Current data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future
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Latest forum messages
Incoming & Unnumbered Active Regions 1661Unspecified geomagnetic activity 2221AR4048 114New satellites - Proba-3, PUNCH, SWFO-L1, GOES-U/19 36Filaments and prominences 750
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| Last geomagnetic storm | 2025/04/04 | Kp5+ (G1) |
| Spotless days | |
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| Monthly mean Sunspot Number | |
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