Viewing archive of Thursday, 27 May 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 May 27 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 147 Issued at 2200Z on 27 May 2021IA. 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 C3 event observed at
26/2124Z from Region 2826 (N24W60). There are currently 2 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
with a chance for a C-class flares and a slight chance for an M-class
flare on days one and two (28 May, 29 May) and expected to be very low
with a slight chance for a C-class flare on day three (30 May).
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 448 km/s at 27/2035Z. Total IMF reached 16
nT at 27/0254Z. The maximum southward component of Bz reached -11 nT at
27/0518Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 187 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on day one (28 May) and quiet levels
on days two and three (29 May, 30 May).
III. Event Probabilities 28 May to 30 May
| Class M | 10% | 10% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 27 May 083 Predicted 28 May-30 May 083/081/080 90 Day Mean 27 May 077
V. Geomagnetic A Indices
Observed Afr/Ap 26 May 012/014 Estimated Afr/Ap 27 May 017/021 Predicted Afr/Ap 28 May-30 May 008/010-005/005-007/008
VI. Geomagnetic Activity Probabilities 28 May to 30 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 10% | 15% |
| Minor storm | 05% | 01% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 30% | 20% | 25% |
| Major-severe storm | 30% | 10% | 25% |
All times in UTC
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