Viewing archive of Sunday, 20 March 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 Mar 20 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 079 Issued at 2200Z on 20 Mar 2011IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z
Solar activity was at very low levels. Region 1175
(N14W36) continued to grow in areal coverage and produced the
largest event of the period, a B7 X-ray event at 20/0733Z. Surging
and low-level B-class X-ray emissions from the vicinity of the SE
limb signal the return of old Region 1165 (S20, L=198).
IB. Solar Activity Forecast
Solar activity is expected to be at
predominately very low levels with a chance for C-class events for
the next three days (21 - 23 March). A slight chance for isolated
M-class activity exists all three days due to the return of old
Regions 1165 late on 21 March and 1164 (N24, L=179) late on 22
March.
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic field was quiet. Solar wind velocities at the ACE
satellite remained low, averaging about 350 km/s. The Bz component
of the interplanetary magnetic field was southward the entire
period, not varying much beyond 0 to -5 nT.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at predominately quiet levels for days one and two
(21 - 22 March). By midday on day three (23 March), a small coronal
hole high speed stream is expected to rotate into a geoeffective
position.
III. Event Probabilities 21 Mar to 23 Mar
| Class M | 10% | 20% | 20% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 20 Mar 092 Predicted 21 Mar-23 Mar 095/100/105 90 Day Mean 20 Mar 094
V. Geomagnetic A Indices
Observed Afr/Ap 19 Mar 002/004 Estimated Afr/Ap 20 Mar 003/005 Predicted Afr/Ap 21 Mar-23 Mar 005/005-005/005-008/008
VI. Geomagnetic Activity Probabilities 21 Mar to 23 Mar
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 15% |
| Minor storm | 01% | 01% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 20% |
| Minor storm | 01% | 01% | 10% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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