Viewing archive of Saturday, 16 October 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Oct 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 289 Issued at 2200Z on 16 Oct 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 1 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
on days one, two, and three (17 Oct, 18 Oct, 19 Oct).
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 422 km/s at 16/0932Z. Total IMF reached 9
nT at 16/0140Z. The maximum southward component of Bz reached -7 nT at
16/0027Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 671 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet levels on day one (17 Oct) and quiet to active levels on
days two and three (18 Oct, 19 Oct).
III. Event Probabilities 17 Oct to 19 Oct
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 16 Oct 078 Predicted 17 Oct-19 Oct 078/078/078 90 Day Mean 16 Oct 083
V. Geomagnetic A Indices
Observed Afr/Ap 15 Oct 004/006 Estimated Afr/Ap 16 Oct 005/006 Predicted Afr/Ap 17 Oct-19 Oct 006/005-009/012-012/012
VI. Geomagnetic Activity Probabilities 17 Oct to 19 Oct
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 30% | 30% |
| Minor storm | 01% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 30% | 30% |
| Major-severe storm | 20% | 35% | 35% |
All times in UTC
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| 2026 | 3 days (3%) |
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