Viewing archive of Monday, 17 May 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 May 17 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 137 Issued at 2200Z on 17 May 2021IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z Solar activity has been at very low levels for the past 24
hours. There are currently 1 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
with a slight chance for a C-class flare on days one and two (18 May, 19
May) and expected to be very low on day three (20 May).
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 433 km/s at 17/1057Z. Total IMF reached 8 nT at
17/1954Z. The maximum southward component of Bz reached -7 nT at
17/1921Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 414 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to minor storm levels on day one (18 May), unsettled to
active levels on day two (19 May) and quiet to active levels on day
three (20 May).
III. Event Probabilities 18 May to 20 May
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 17 May 075 Predicted 18 May-20 May 076/075/074 90 Day Mean 17 May 076
V. Geomagnetic A Indices
Observed Afr/Ap 16 May 004/005 Estimated Afr/Ap 17 May 008/012 Predicted Afr/Ap 18 May-20 May 013/018-017/020-012/012
VI. Geomagnetic Activity Probabilities 18 May to 20 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 40% | 30% | 25% |
| Minor storm | 25% | 15% | 05% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 15% |
| Minor storm | 25% | 25% | 30% |
| Major-severe storm | 60% | 40% | 30% |
All times in UTC
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