Viewing archive of Sunday, 21 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 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 080 Issued at 2200Z on 21 MAR 1999IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z SOLAR ACTIVITY WAS LOW. A C1 X-RAY FLARE OCCURRED AT
21/0642UT. NO OPTICAL FLARE REPORTS WERE RECEIVED DURING THE PAST
DAY. ALL SUNSPOT REGIONS CURRENTLY ON THE DISK ARE RELATIVELY SMALL
AND SIMPLE. REGIONS 8494 (S24W12) AND 8496 (S11W32) ARE GROWING
SLOWLY.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE VERY
LOW TO LOW. ISOLATED C-CLASS FLARES ARE POSSIBLE.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED.
III. Event Probabilities 22 MAR to 24 MAR
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 21 MAR 124 Predicted 22 MAR-24 MAR 120/115/115 90 Day Mean 21 MAR 142
V. Geomagnetic A Indices
OBSERVED AFR/AP 20 MAR 003/006 ESTIMATED AFR/AP 21 MAR 008/007 PREDICTED AFR/AP 22 MAR-24 MAR 010/005-005/007-005/009
VI. Geomagnetic Activity Probabilities 22 MAR to 24 MAR
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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