Viewing archive of Monday, 11 September 2023
Solar activity report
Report of Solar-Geophysical Activity 2023 Sep 11 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 254 Issued at 2200Z on 11 Sep 2023IA. Analysis of Solar Active Regions and Activity from 10-2100Z to 11-2100Z 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
11/0128Z from Region 3429 (N10E46). There are currently 10 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
(12 Sep, 13 Sep, 14 Sep).
IIA. Geophysical Activity Summary 10-2100Z to 11-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 429 km/s at 11/1902Z. Total IMF reached 8 nT at
11/0133Z. The maximum southward component of Bz reached -6 nT at
11/0038Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 174 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on days one and two (12 Sep, 13 Sep) and
quiet to unsettled levels on day three (14 Sep). Protons greater than 10
Mev have a slight chance of crossing threshold on day three (14 Sep).
III. Event Probabilities 12 Sep to 14 Sep
| Class M | 55% | 55% | 55% |
| Class X | 10% | 10% | 10% |
| Proton | 05% | 05% | 10% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 11 Sep 176 Predicted 12 Sep-14 Sep 175/170/168 90 Day Mean 11 Sep 163
V. Geomagnetic A Indices
Observed Afr/Ap 10 Sep 006/003 Estimated Afr/Ap 11 Sep 007/007 Predicted Afr/Ap 12 Sep-14 Sep 011/015-011/012-009/010
VI. Geomagnetic Activity Probabilities 12 Sep to 14 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 30% | 20% |
| Minor storm | 10% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 25% | 15% |
| Minor storm | 30% | 25% | 20% |
| Major-severe storm | 20% | 20% | 20% |
All times in UTC
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