Viewing archive of Monday, 20 December 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Dec 20 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 354 Issued at 2200Z on 20 Dec 2021IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z
Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M1 event observed at
20/1136Z from Region 2908 (S21W11). There are currently 8 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with
a chance for M-class flares on day one (21 Dec) and expected to be low
with a slight chance for an M-class flare on days two and three (22 Dec,
23 Dec).
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic
field has been at quiet to minor storm levels for the past 24 hours.
Solar wind speed reached a peak of 631 km/s at 20/1826Z. Total IMF
reached 19 nT at 19/2105Z. The maximum southward component of Bz reached
-12 nT at 19/2317Z. Electrons greater than 2 MeV at geosynchronous
orbit reached a peak level of 227 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on days one and two (21 Dec, 22 Dec) and
quiet to unsettled levels on day three (23 Dec).
III. Event Probabilities 21 Dec to 23 Dec
| Class M | 25% | 20% | 20% |
| Class X | 05% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 20 Dec 123 Predicted 21 Dec-23 Dec 124/122/120 90 Day Mean 20 Dec 089
V. Geomagnetic A Indices
Observed Afr/Ap 19 Dec 008/012 Estimated Afr/Ap 20 Dec 013/017 Predicted Afr/Ap 21 Dec-23 Dec 012/016-010/012-008/008
VI. Geomagnetic Activity Probabilities 21 Dec to 23 Dec
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 25% | 15% |
| Minor storm | 15% | 05% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 15% | 15% |
| Minor storm | 30% | 30% | 25% |
| Major-severe storm | 45% | 30% | 20% |
All times in UTC
Current data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future
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