Viewing archive of Wednesday, 27 September 2023
Solar activity report
Report of Solar-Geophysical Activity 2023 Sep 27 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 270 Issued at 2200Z on 27 Sep 2023IA. 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 C4 event observed at
27/0546Z. 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 and a slight chance for an X-class flare on
day one (28 Sep) and expected to be low with a chance for M-class flares
on days two and three (29 Sep, 30 Sep).
IIA. Geophysical Activity Summary 26-2100Z to 27-2100Z
The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed reached a peak of 529 km/s at 26/2104Z. Total IMF reached 6
nT at 27/0456Z. The maximum southward component of Bz reached -4 nT at
27/1807Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 3755 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on days one and two (28 Sep, 29 Sep)
and quiet to active levels on day three (30 Sep). Protons greater than
10 Mev have a slight chance of crossing threshold on day one (28 Sep).
III. Event Probabilities 28 Sep to 30 Sep
| Class M | 35% | 30% | 30% |
| Class X | 10% | 05% | 05% |
| Proton | 10% | 05% | 05% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 27 Sep 156 Predicted 28 Sep-30 Sep 160/158/155 90 Day Mean 27 Sep 162
V. Geomagnetic A Indices
Observed Afr/Ap 26 Sep 026/032 Estimated Afr/Ap 27 Sep 014/016 Predicted Afr/Ap 28 Sep-30 Sep 007/008-007/008-010/012
VI. Geomagnetic Activity Probabilities 28 Sep to 30 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 15% | 30% |
| Minor storm | 05% | 05% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 20% | 30% |
| Major-severe storm | 20% | 20% | 40% |
All times in UTC
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