Viewing archive of Wednesday, 27 October 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Oct 27 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 300 Issued at 2200Z on 27 Oct 2021IA. Analysis of Solar Active Regions and Activity from 26-2100Z to 27-2100Z Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C8 event observed at
27/0608Z from Region 2887 (S26E04). There are currently 5 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 (28 Oct,
29 Oct, 30 Oct).
IIA. Geophysical Activity Summary 26-2100Z to 27-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 417 km/s at 27/0528Z. Total IMF reached 7 nT at
26/2136Z. The maximum southward component of Bz reached -2 nT at
27/0116Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 138 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet levels on day one (28 Oct), quiet to unsettled levels on
day two (29 Oct) and quiet to active levels on day three (30 Oct).
III. Event Probabilities 28 Oct to 30 Oct
| Class M | 15% | 15% | 15% |
| Class X | 05% | 05% | 05% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 27 Oct 111 Predicted 28 Oct-30 Oct 111/112/110 90 Day Mean 27 Oct 084
V. Geomagnetic A Indices
Observed Afr/Ap 26 Oct 003/003 Estimated Afr/Ap 27 Oct 004/004 Predicted Afr/Ap 28 Oct-30 Oct 006/005-006/008-009/010
VI. Geomagnetic Activity Probabilities 28 Oct to 30 Oct
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 15% | 30% |
| Minor storm | 01% | 05% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 25% | 30% |
| Major-severe storm | 15% | 25% | 40% |
All times in UTC
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