Viewing archive of Saturday, 24 April 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Apr 24 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 114 Issued at 2200Z on 24 Apr 2021IA. Analysis of Solar Active Regions and Activity from 23-2100Z to 24-2100Z
Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C2 event observed at
23/2312Z from Region 2817 (N18, L=336). 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 (25 Apr,
26 Apr, 27 Apr).
IIA. Geophysical Activity Summary 23-2100Z to 24-2100Z
The geomagnetic
field has been at quiet to minor storm levels for the past 24 hours.
Solar wind speed reached a peak of 519 km/s at 24/0459Z. Total IMF
reached 11 nT at 23/2113Z. The maximum southward component of Bz reached
-10 nT at 23/2118Z. Electrons greater than 2 MeV at geosynchronous
orbit reached a peak level of 4918 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to major storm levels on day one (25 Apr), quiet to
active levels on day two (26 Apr) and quiet levels on day three (27
Apr).
III. Event Probabilities 25 Apr to 27 Apr
| Class M | 10% | 10% | 10% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 24 Apr 079 Predicted 25 Apr-27 Apr 079/079/078 90 Day Mean 24 Apr 076
V. Geomagnetic A Indices
Observed Afr/Ap 23 Apr 015/012 Estimated Afr/Ap 24 Apr 009/009 Predicted Afr/Ap 25 Apr-27 Apr 019/025-013/015-006/005
VI. Geomagnetic Activity Probabilities 25 Apr to 27 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 30% | 10% |
| Minor storm | 35% | 15% | 01% |
| Major-severe storm | 10% | 05% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 05% | 15% | 15% |
| Minor storm | 20% | 30% | 20% |
| Major-severe storm | 75% | 50% | 10% |
All times in UTC
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