Viewing archive of Wednesday, 21 April 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Apr 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 111 Issued at 2200Z on 21 Apr 2021IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
IB. Solar Activity Forecast
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
IIB. Geophysical Activity Forecast
III. Event Probabilities 22 Apr to 24 Apr
| Class M | 10% | 05% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Apr 078 Predicted 22 Apr-24 Apr 080/078/078 90 Day Mean 21 Apr 076
V. Geomagnetic A Indices
Observed Afr/Ap 20 Apr 010/012 Estimated Afr/Ap 21 Apr 007/008 Predicted Afr/Ap 22 Apr-24 Apr 005/005-009/010-009/010
VI. Geomagnetic Activity Probabilities 22 Apr to 24 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 40% | 40% |
| Minor storm | 01% | 15% | 15% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 10% |
| Minor storm | 20% | 25% | 25% |
| Major-severe storm | 20% | 50% | 50% |
All times in UTC
Current data suggests there is a moderate possibility for aurora to appear at the following high latitude regions in the near future
Whitehorse, YTFairbanks, AK
Current data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future
Edmonton, AB, Gillam, MB, Saskatoon, SK, Yellowknife, NTAnchorage, AK, Juneau, AK
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