Viewing archive of Friday, 16 April 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Apr 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 106 Issued at 2200Z on 16 Apr 2021IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z Solar activity has been at very low levels for the past 24
hours. There are currently 3 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
with a chance for a C-class flares on days one, two, and three (17 Apr,
18 Apr, 19 Apr).
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 490 km/s at 16/1213Z. Total IMF reached 13
nT at 16/1558Z. The maximum southward component of Bz reached -10 nT at
16/1806Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 134 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to minor storm levels on day one (17 Apr) and quiet to
active levels on days two and three (18 Apr, 19 Apr).
III. Event Probabilities 17 Apr to 19 Apr
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 16 Apr 077 Predicted 17 Apr-19 Apr 078/078/078 90 Day Mean 16 Apr 076
V. Geomagnetic A Indices
Observed Afr/Ap 15 Apr 011/010 Estimated Afr/Ap 16 Apr 016/020 Predicted Afr/Ap 17 Apr-19 Apr 015/020-015/018-011/012
VI. Geomagnetic Activity Probabilities 17 Apr to 19 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 35% | 35% |
| Minor storm | 25% | 15% | 15% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 10% |
| Minor storm | 25% | 25% | 25% |
| Major-severe storm | 65% | 50% | 50% |
All times in UTC
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