Viewing archive of Monday, 18 September 2023
Solar activity report
Report of Solar-Geophysical Activity 2023 Sep 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 261 Issued at 2200Z on 18 Sep 2023IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z
Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C2 event observed at
18/1041Z from Region 3435 (N09E56). There are currently 9 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 (19
Sep, 20 Sep, 21 Sep).
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic
field has been at quiet to minor storm levels for the past 24 hours.
Solar wind speed reached a peak of 598 km/s at 18/1617Z. Total IMF
reached 22 nT at 18/1540Z. The maximum southward component of Bz reached
-18 nT at 18/1644Z. Electrons greater than 2 MeV at geosynchronous
orbit reached a peak level of 734 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at unsettled to major storm levels on day one (19 Sep), quiet to
active levels on day two (20 Sep) and quiet to unsettled levels on day
three (21 Sep).
III. Event Probabilities 19 Sep to 21 Sep
| Class M | 20% | 20% | 20% |
| Class X | 01% | 01% | 01% |
| Proton | 05% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Sep 155 Predicted 19 Sep-21 Sep 154/154/152 90 Day Mean 18 Sep 162
V. Geomagnetic A Indices
Observed Afr/Ap 17 Sep 014/020 Estimated Afr/Ap 18 Sep 023/029 Predicted Afr/Ap 19 Sep-21 Sep 022/035-014/015-008/008
VI. Geomagnetic Activity Probabilities 19 Sep to 21 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 30% | 20% |
| Minor storm | 40% | 10% | 05% |
| Major-severe storm | 35% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 05% | 15% | 15% |
| Minor storm | 20% | 20% | 20% |
| Major-severe storm | 75% | 20% | 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
Oulu, Rovaniemi, SodankyläKirkenes, Trondheim
Arkhangelsk, Murmansk, Vorkuta
Kiruna, Luleå, Sundsvall, Umeå
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