Viewing archive of Saturday, 13 March 1999
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 1999 Mar 13 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 072 Issued at 2200Z on 13 MAR 1999IA. Analysis of Solar Active Regions and Activity from 12-2100Z to 13-2100Z
SOLAR ACTIVITY INCREASED TO MODERATE LEVELS. REGION
8487 (N17E39) REMAINED A RELATIVELY SMALL D-TYPE GROUP AND SHOWED
MINOR PENUMBRAL GROWTH AS WELL AS SOME MAGNETIC SHEAR IN THE
VICINITY OF THE DOMINANT LEADER SPOT. IT PRODUCED AN IMPULSIVE M1/1N
AT 13/2034Z AND NUMEROUS SUBFLARES EARLIER IN THE DAY, A FEW OF
WHICH REACHED C-CLASS. NONE OF THESE FLARES WERE IMPRESSIVE IN RADIO
EMISSION. REGION 8485 (N23E00) REMAINED A MODERATE-SIZED E-TYPE
GROUP WITH SOME MIXED POLARITIES. IT WAS GENERALLY STABLE AND
PRODUCED ISOLATED SUBFARES. THE REMAINING REGIONS WERE QUIET AND
STABLE.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE AT
MOSTLY LOW LEVELS. HOWEVER, ANOTHER ISOLATED M-CLASS FLARE COULD
OCCUR FROM REGION 8487 SOMETIME DURING THE PERIOD. REGION 8485 ALSO
PROVIDES A SLIGHT CHANCE FOR AN ISOLATED M-CLASS FLARE.
IIA. Geophysical Activity Summary 12-2100Z to 13-2100Z
GEOMAGNETIC FIELD ACTIVITY INCREASED TO UNSETTLED TO ACTIVE LEVELS
DURING 13/1200 - 1400Z. OTHERWISE, THE FIELD WAS AT QUIET TO
UNSETTLED LEVELS.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE AT UNSETTLED TO ACTIVE LEVELS THROUGH THE PERIOD.
BRIEF MINOR STORM PERIODS ARE ALSO POSSIBLE. THIS ACTIVITY IS
EXPECTED IN RESPONSE TO CME EFFECTS. AN ISOLATED, POSITIVE POLARITY
CORONAL HOLE MAY ALSO DISTURB THE FIELD SOMETIME DURING THE PERIOD.
III. Event Probabilities 14 MAR to 16 MAR
| Class M | 30% | 30% | 30% |
| Class X | 05% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 13 MAR 144 Predicted 14 MAR-16 MAR 145/145/140 90 Day Mean 13 MAR 142
V. Geomagnetic A Indices
OBSERVED AFR/AP 12 MAR 009/010 ESTIMATED AFR/AP 13 MAR 007/009 PREDICTED AFR/AP 14 MAR-16 MAR 020/015-015/012-015/010
VI. Geomagnetic Activity Probabilities 14 MAR to 16 MAR
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 45% | 40% | 40% |
| Minor storm | 20% | 10% | 10% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 55% | 45% | 45% |
| Minor storm | 25% | 15% | 15% |
| Major-severe storm | 10% | 05% | 05% |
All times in UTC
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