Viewing archive of Thursday, 21 September 2023
Solar activity report
Report of Solar-Geophysical Activity 2023 Sep 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 264 Issued at 2200Z on 21 Sep 2023IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
Solar activity has been at high levels for the past 24 hours.
The largest solar event of the period was a M8 event observed at
21/1254Z from Region 3435 (N08E16). There are currently 11 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is likely to be moderate
with a slight chance for an X-class flare on days one, two, and three
(22 Sep, 23 Sep, 24 Sep).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 474 km/s at 20/2119Z. Total IMF reached 5
nT at 21/0709Z. The maximum southward component of Bz reached -4 nT at
21/1239Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 1416 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on day one (22 Sep), unsettled to minor
storm levels on day two (23 Sep) and quiet to minor storm levels on day
three (24 Sep).
III. Event Probabilities 22 Sep to 24 Sep
| Class M | 55% | 55% | 55% |
| Class X | 10% | 10% | 10% |
| Proton | 05% | 05% | 05% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Sep 168 Predicted 22 Sep-24 Sep 162/162/165 90 Day Mean 21 Sep 161
V. Geomagnetic A Indices
Observed Afr/Ap 20 Sep 015/020 Estimated Afr/Ap 21 Sep 008/009 Predicted Afr/Ap 22 Sep-24 Sep 011/015-016/022-018/022
VI. Geomagnetic Activity Probabilities 22 Sep to 24 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 35% | 35% |
| Minor storm | 15% | 25% | 20% |
| Major-severe storm | 01% | 05% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 15% |
| Minor storm | 30% | 25% | 20% |
| Major-severe storm | 55% | 65% | 30% |
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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