Viewing archive of Wednesday, 15 September 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 Sep 15 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 258 Issued at 2200Z on 15 Sep 2021IA. Analysis of Solar Active Regions and Activity from 14-2100Z to 15-2100Z Solar activity has been at very low levels for the past 24
hours. There are currently 0 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
on days one, two, and three (16 Sep, 17 Sep, 18 Sep).
IIA. Geophysical Activity Summary 14-2100Z to 15-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 465 km/s at 14/2355Z. Electrons greater than 2 MeV at
geosynchronous orbit reached a peak level of 456 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet levels on day one (16 Sep) and quiet to active levels on
days two and three (17 Sep, 18 Sep).
III. Event Probabilities 16 Sep to 18 Sep
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 15 Sep 075 Predicted 16 Sep-18 Sep 075/075/075 90 Day Mean 15 Sep 082
V. Geomagnetic A Indices
Observed Afr/Ap 14 Sep 005/006 Estimated Afr/Ap 15 Sep 005/005 Predicted Afr/Ap 16 Sep-18 Sep 006/005-012/015-013/015
VI. Geomagnetic Activity Probabilities 16 Sep to 18 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 40% | 45% |
| Minor storm | 01% | 20% | 20% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 10% |
| Minor storm | 20% | 35% | 25% |
| Major-severe storm | 20% | 50% | 65% |
All times in UTC
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