Viewing archive of Thursday, 12 April 2012
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 2012 Apr 12 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 103 Issued at 2200Z on 12 Apr 2012IA. Analysis of Solar Active Regions and Activity from 11-2100Z to 12-2100Z
Solar activity has been at very low levels for the past
24 hours. Region 1455 (N06W05) has been the most active region
producing multiple B-class x-ray events. Region 1455 has shown rapid
growth in area and magnetic complexity, now a D-type beta group. New
Region 1456 (S20W19) was numbered today. Multiple CMEs were observed
during the period but none appear to be Earth directed.
IB. Solar Activity Forecast
Solar activity is expected to be at
very low levels with a chance for C-class activity for the next
three days (13 - 15 April) as Regions 1455 and 1456 continue to grow
and evolve.
IIA. Geophysical Activity Summary 11-2100Z to 12-2100Z
The geomagnetic field has been at quiet to active levels over the
past 24 hours. Characteristics of an anticipated high speed solar
wind stream from a coronal hole were observed by the ACE spacecraft,
with subsequent elevated geomagnetic levels here at Earth.
Measurements from the ACE spacecraft showed an increase in solar
wind speeds from around 370 km/s to around 600 km/s with the total
IMF hovering around 12 nT.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at unsettled to active levels with the chance for
minor storm periods on day one (13 April) as the effects of a
coronal hole high speed stream (CH HSS) continue. Quiet to unsettled
levels with a chance for active periods are expected on day two (14
April) as the effects of the CH HSS wane. Predominantly quiet levels
are expected on day three (15 April) as the geomagnetic field
returns to nominal levels.
III. Event Probabilities 13 Apr to 15 Apr
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 12 Apr 095 Predicted 13 Apr-15 Apr 095/095/095 90 Day Mean 12 Apr 114
V. Geomagnetic A Indices
Observed Afr/Ap 11 Apr 005/004 Estimated Afr/Ap 12 Apr 009/010 Predicted Afr/Ap 13 Apr-15 Apr 013/018-010/010-009/008
VI. Geomagnetic Activity Probabilities 13 Apr to 15 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 30% | 25% |
| Minor storm | 10% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 40% | 35% | 30% |
| Minor storm | 30% | 20% | 15% |
| Major-severe storm | 15% | 10% | 10% |
All times in UTC
Current data suggests there is a moderate possibility for aurora to appear at the following high latitude regions in the near future
VorkutaCurrent data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future
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