Viewing archive of Tuesday, 4 May 2021
Solar activity report
Report of Solar-Geophysical Activity 2021 May 04 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 124 Issued at 2200Z on 04 May 2021IA. Analysis of Solar Active Regions and Activity from 03-2100Z to 04-2100Z 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 (05 May, 06 May, 07 May).
IIA. Geophysical Activity Summary 03-2100Z to 04-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 499 km/s at 03/2351Z. Total IMF reached 6 nT at
04/0409Z. The maximum southward component of Bz reached -4 nT at
04/0002Z. Electrons greater than 2 MeV at geosynchronous orbit reached
a peak level of 239 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet levels on days one, two, and three (05 May, 06 May, 07
May).
III. Event Probabilities 05 May to 07 May
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 04 May 070 Predicted 05 May-07 May 072/072/072 90 Day Mean 04 May 076
V. Geomagnetic A Indices
Observed Afr/Ap 03 May 006/005 Estimated Afr/Ap 04 May 005/006 Predicted Afr/Ap 05 May-07 May 006/005-006/005-006/005
VI. Geomagnetic Activity Probabilities 05 May to 07 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 20% | 20% |
| Minor storm | 20% | 20% | 20% |
| Major-severe storm | 20% | 10% | 10% |
All times in UTC
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