Viewing archive of Thursday, 18 November 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 Nov 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 322 Issued at 2200Z on 18 NOV 1999IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z SOLAR ACTIVITY HAS BEEN MODERATE. DESPITE THE PRESENCE
OF SOME OF THE LARGEST REGIONS OF THE SOLAR CYCLE, THE SUN HAS BEEN
SURPRISINGLY QUIET. THE LARGEST EVENT OF THE PERIOD WAS A M1/1F
FROM REGION 8771 (S14E46). REGION 8765 (S12W20), NOW APPROACHING
1300 MILLIONTHS, CONTINUES TO SLOWLY EVOLVE AND CONTAINS AT LEAST
ONE MAGNETIC DELTA CONFIGURATION. REGION 8772 (NO5E71) WAS
NUMBERED.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE TO HIGH. MOST OF THE REGIONS NOW VISIBLE ON THE SUN HAVE
EITHER PRODUCED M FLARES OR HAVE THE POTENTIAL FOR MAJOR ACTIVITY.
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
THE GEOMAGNETIC FIELD HAS BEEN GENERALLY UNSETTLED THE PAST 24 HOURS.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE UNSETTLED TO ACTIVE. THERE MAY BE SOME INCREASE IN
ACTIVITY AS A CONSEQUENCE OF SUSPECTED CME ACTIVITY OVER THE PAST
SEVERAL DAYS.
III. Event Probabilities 19 NOV to 21 NOV
| Class M | 90% | 90% | 90% |
| Class X | 30% | 30% | 30% |
| Proton | 15% | 15% | 15% |
| PCAF | YELLOW | ||
IV. Penticton 10.7 cm Flux
Observed 18 NOV 218 Predicted 19 NOV-21 NOV 210/200/200 90 Day Mean 18 NOV 166
V. Geomagnetic A Indices
OBSERVED AFR/AP 17 NOV 008/010 ESTIMATED AFR/AP 18 NOV 011/012 PREDICTED AFR/AP 19 NOV-21 NOV 020/020-020/020-015/012
VI. Geomagnetic Activity Probabilities 19 NOV to 21 NOV
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 45% | 45% | 40% |
| Minor storm | 20% | 20% | 15% |
| Major-severe storm | 10% | 10% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 50% | 50% | 40% |
| Minor storm | 25% | 25% | 20% |
| Major-severe storm | 10% | 10% | 10% |
All times in UTC
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