Viewing archive of Sunday, 17 September 2023
Solar activity report
Report of Solar-Geophysical Activity 2023 Sep 17 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 260 Issued at 2200Z on 17 Sep 2023IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z
Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C3 event observed at
17/1604Z from Region 3435 (N10E60). There are currently 5 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with
a slight chance for an M-class flare on days one, two, and three (18
Sep, 19 Sep, 20 Sep).
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic
field has been at unsettled to active levels for the past 24 hours.
Solar wind speed reached a peak of 508 km/s at 17/0424Z. Total IMF
reached 11 nT at 17/0412Z. The maximum southward component of Bz reached
-8 nT at 17/0205Z. Electrons greater than 2 MeV at geosynchronous orbit
reached a peak level of 167 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on day one (18 Sep), unsettled to
major storm levels on day two (19 Sep) and quiet to active levels on day
three (20 Sep).
III. Event Probabilities 18 Sep to 20 Sep
| Class M | 20% | 20% | 15% |
| Class X | 05% | 01% | 01% |
| Proton | 05% | 05% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 17 Sep 145 Predicted 18 Sep-20 Sep 145/140/140 90 Day Mean 17 Sep 162
V. Geomagnetic A Indices
Observed Afr/Ap 16 Sep 005/010 Estimated Afr/Ap 17 Sep 014/019 Predicted Afr/Ap 18 Sep-20 Sep 008/008-022/035-014/015
VI. Geomagnetic Activity Probabilities 18 Sep to 20 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 25% | 25% |
| Minor storm | 05% | 40% | 05% |
| Major-severe storm | 01% | 35% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 05% | 15% |
| Minor storm | 25% | 20% | 20% |
| Major-severe storm | 35% | 75% | 25% |
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
Gillam, MBNuuk
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