Viewing archive of Wednesday, 22 December 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 Dec 22 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 356 Issued at 2200Z on 22 DEC 1999IA. Analysis of Solar Active Regions and Activity from 21-2100Z to 22-2100Z SOLAR ACTIVITY WAS HIGH. REGION 8806 (N19E12) PRODUCED
AN IMPULSIVE M5/1B FLARE AT 1904Z. THIS REGION WAS QUITE ACTIVE
DURING THE PERIOD AND SHOWS A COMPLEX INVERSION LINE WITH SOME
EVIDENCE FOR SHEARED MAGNETIC FIELDS. THE MAGNETIC DELTA
CONFIGURATION PERSISTED THROUGH MOST OF THE DAY BUT MAY BE BREAKING
UP AS OF FORECAST FILE TIME. AN ADDITIONAL M-CLASS EVENT OCCURRED
TODAY AT 0216Z. THIS EVENT WAS COMPLICATED IN THAT IT STARTED WITH
AN ERUPTING FILAMENT, FOLLOWED BY EVENT LEVEL FLARES IN 8807
(N10E16) AND 8806. REGION 8798 (S13W47) SHOWED SOME DECAY TODAY AND
EXHIBITED FREQUENT PLAGE FLUCTUATIONS, BUT DID NOT PRODUCE
SIGNIFICANT FLARE ACTIVITY.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE. REGIONS 8798 AND 8806 ARE BOTH GOOD CANDIDATES FOR
PRODUCING ADDITIONAL M-FLARES. THERE IS A FAIR CHANCE FOR AN
ISOLATED MAJOR FLARE EVENT FROM REGION 8806 OVER THE NEXT THREE
DAYS.
IIA. Geophysical Activity Summary 21-2100Z to 22-2100Z
THE GEOMAGNETIC FIELD WAS QUIET.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE MOSTLY QUIET FOR THE NEXT THREE DAYS.
III. Event Probabilities 23 DEC to 25 DEC
| Class M | 75% | 75% | 75% |
| Class X | 20% | 20% | 20% |
| Proton | 10% | 10% | 10% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 22 DEC 202 Predicted 23 DEC-25 DEC 200/200/195 90 Day Mean 22 DEC 173
V. Geomagnetic A Indices
OBSERVED AFR/AP 21 DEC 001/002 ESTIMATED AFR/AP 22 DEC 001/003 PREDICTED AFR/AP 23 DEC-25 DEC 005/007-005/007-005/007
VI. Geomagnetic Activity Probabilities 23 DEC to 25 DEC
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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