Viewing archive of Wednesday, 20 July 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 Jul 20 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 201 Issued at 2200Z on 20 Jul 2011IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z
Solar activity was very low. There were five numbered
active regions today, but most remained quiet and stable. Regions
1254 (S22W17) and 1259 (N25E42) were classified as Cso Beta groups.
Only 1254 produced any x-ray events during the period, the largest a
B8 flare at 20/1551Z.
IB. Solar Activity Forecast
Solar activity is expected to be very
low to low with the chance for a C-class event for the next 3 days
(21-23 July).
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic field was mostly unsettled to active 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 for the next 3 days (21-23
July), with an isolated minor storm possible at high latitudes. This
activity is forecast as the result of high speed stream effects from
a currently geoeffective coronal hole.
III. Event Probabilities 21 Jul to 23 Jul
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 20 Jul 100 Predicted 21 Jul-23 Jul 100/100/100 90 Day Mean 20 Jul 097
V. Geomagnetic A Indices
Observed Afr/Ap 19 Jul 010/018 Estimated Afr/Ap 20 Jul 016/018 Predicted Afr/Ap 21 Jul-23 Jul 018/015-014/012-007/008
VI. Geomagnetic Activity Probabilities 21 Jul to 23 Jul
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 40% | 40% | 30% |
| Minor storm | 30% | 30% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 50% | 50% | 40% |
| Minor storm | 40% | 40% | 20% |
| Major-severe storm | 10% | 05% | 01% |
All times in UTC
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