Viewing archive of Sunday, 1 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 01 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 092 Issued at 2200Z on 01 Apr 2012IA. Analysis of Solar Active Regions and Activity from 31-2100Z to 01-2100Z
Solar activity was very low. Only minor B-class/Sf
flares were observed, one from Region 1444 (N21W86) at 31/2107 and
from 1450 (N17E22) at 01/1454Z. The event from Region 1444 was
associated with a narrow eruption visible in SDO/AIA 304 imagery.
The ejecta is not expected to be geoeffective. The remaining
regions were quiet and magnetically simple.
IB. Solar Activity Forecast
Solar activity is expected to be very
low to low with a slight chance for a C-class flare for the first
two days of the period (02-03 April). The probability of a C class
event increases on Day 3 (04 April) with the anticipated return of
Old Region 1434 (S22 L=207).
IIA. Geophysical Activity Summary 31-2100Z to 01-2100Z
The geomagneic field was quiet. Solar wind speed measured at the ACE
spacecraft gradually declined from around 380 km/s at the beginning
of the period to about 320 km/s by the end. At approximately
01/0800Z, ACE indicated a solar sector boundary crossing to a
negative orientation accompanied by increased density and slight (-5
nT) southward Bz.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to begin the period at quiet levels. On Day 3 (04 April),
it will become unsettled with the possiblity of an isolated active
period as a coronal hole high speed stream becomes geoeffective.
III. Event Probabilities 02 Apr to 04 Apr
| Class M | 05% | 05% | 10% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 01 Apr 107 Predicted 02 Apr-04 Apr 110/115/125 90 Day Mean 01 Apr 118
V. Geomagnetic A Indices
Observed Afr/Ap 31 Mar 004/004 Estimated Afr/Ap 01 Apr 006/006 Predicted Afr/Ap 02 Apr-04 Apr 006/005-006/005-007/008
VI. Geomagnetic Activity Probabilities 02 Apr to 04 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 05% | 05% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 20% |
| Minor storm | 15% | 15% | 25% |
| Major-severe storm | 05% | 05% | 15% |
All times in UTC
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