Viewing archive of Thursday, 4 May 2017
Solar activity report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 2017 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 2017IA. 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 2 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, 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 374 km/s at 04/1755Z. Total IMF reached 8 nT at
04/2035Z. The maximum southward component of Bz reached -2 nT at
04/1837Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 5333 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on day one (05 May) and quiet levels
on days two and three (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 074 Predicted 05 May-07 May 076/076/076 90 Day Mean 04 May 077
V. Geomagnetic A Indices
Observed Afr/Ap 03 May 002/003 Estimated Afr/Ap 04 May 005/005 Predicted Afr/Ap 05 May-07 May 008/008-005/005-006/005
VI. Geomagnetic Activity Probabilities 05 May to 07 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 05% |
| Minor storm | 05% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 15% | 20% |
| Major-severe storm | 20% | 15% | 10% |
All times in UTC
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