Viewing archive of Sunday, 1 May 2011
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 2011 May 01 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 121 Issued at 2200Z on 01 May 2011IA. Analysis of Solar Active Regions and Activity from 30-2100Z to 01-2100Z Solar activity was low. Region 1195 (S16W99) produced
the sole event of the period, a C1 flare at 01/0814Z.
IB. Solar Activity Forecast
Solar activity is forecast to be very
low to low for the next 3 days (2-4 May).
IIA. Geophysical Activity Summary 30-2100Z to 01-2100Z
The geomagnetic field was unsettled to active at mid latitudes. Minor
to major storm conditions occurred at high latitudes due to Coronal
Hole (CH) high-speed stream (HSS) effects. Solar winds speeds were
sustained above 620 km/s during the period. The greater than 2 MeV
electron flux at geosynchronous orbit reached high levels during the
period.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be mostly unsettled to active with a chance for a minor
storm on day 1 (2 May). Conditions are forecast to be unsettled to
active on day 2 (3 May) and return to quiet on day 3 (4 May) as CH
HSS effects are expected to subside.
III. Event Probabilities 02 May to 04 May
| Class M | 10% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 01 May 106 Predicted 02 May-04 May 105/100/100 90 Day Mean 01 May 108
V. Geomagnetic A Indices
Observed Afr/Ap 30 Apr 017/024 Estimated Afr/Ap 01 May 016/022 Predicted Afr/Ap 02 May-04 May 012/015-008/010-005/005
VI. Geomagnetic Activity Probabilities 02 May to 04 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 40% | 30% | 20% |
| Minor storm | 30% | 10% | 01% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 50% | 40% | 20% |
| Minor storm | 25% | 15% | 01% |
| Major-severe storm | 10% | 01% | 01% |
All times in UTC
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