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Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 272 Issued at 2200Z on 29 Sep 2023

By Keith Cowing
Status Report
NOAA SWPC
September 29, 2023
Filed under , , ,
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast SDF Number 272 Issued at 2200Z on 29 Sep 2023
Space weather
NOAA SWPC

IA. Analysis of Solar Active Regions and Activity from 28/2100Z to 29/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C7 event observed at 29/1824Z. There are currently 7 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be low with a chance for M-class flares on days one, two, and three (30 Sep, 01 Oct, 02 Oct).

IIA. Geophysical Activity Summary 28/2100Z to 29/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed reached a peak of 520 km/s at 29/0945Z. Total IMF reached 8 nT at 29/0945Z. The maximum southward component of Bz reached -7 nT at 29/0912Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 3085 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on days one and three (30 Sep, 02 Oct) and quiet to unsettled levels on day two (01 Oct).

III. Event probabilities 30 Sep-02 Oct
Class M 30/30/30
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 29 Sep 155
Predicted 30 Sep-02 Oct 152/148/145
90 Day Mean 29 Sep 162

V. Geomagnetic A Indices
Observed Afr/Ap 28 Sep 005/009
Estimated Afr/Ap 29 Sep 009/013
Predicted Afr/Ap 30 Sep-02 Oct 008/010-008/008-012/015

VI. Geomagnetic Activity Probabilities 30 Sep-02 Oct
A. Middle Latitudes
Active 30/20/40
Minor Storm 10/05/20
Major-severe storm 01/01/05
B. High Latitudes
Active 15/15/20
Minor Storm 30/25/30
Major-severe storm 40/25/35

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