Viewing archive of Tuesday, 16 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 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 075 Issued at 2200Z on 16 MAR 1999IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z SOLAR ACTIVITY CONTINUED AT MODERATE LEVELS. REGION
8485 (N23W39) REMAINED A LARGE F-TYPE GROUP WITH MIXED POLARITIES
AND SHOWED AN OVERALL INCREASE IN ACTIVITY, THOUGH NO SIGNIFICANT
CHANGES WERE APPARENT IN ITS SIZE OR STRUCTURE. IT PRODUCED AN
IMPULSIVE M1/1F AT 16/0635UT ALONG WITH SEVERAL C-CLASS SUBFLARES.
ALL OF THESE FLARES WERE WEAK IN RADIO EMISSION. REGION 8487
(N16W02) PRODUCED ISOLATED B-CLASS SUBFLARES AND SHOWED NO
SIGNIFICANT CHANGES. A 16-DEGREE FILAMENT, LAST SEEN NEAR S35W32,
DISAPPEARED EARLY IN THE PERIOD. THERE WAS A CME ASSOCIATED WITH THE
DISAPPEARANCE, BUT IT DID NOT APPEAR TO BE EARTH-DIRECTED. NEW
REGION 8489 (N13W28) WAS NUMBERED.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE. REGIONS 8485 AND 8487 APPEAR CAPABLE OF PRODUCING M-CLASS
FLARES. THERE IS ALSO A SLIGHT CHANCE FOR A MAJOR FLARE FROM REGION
8485.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
THE GEOMAGNETIC FIELD WAS QUIET.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE AT MOSTLY QUIET TO UNSETTLED LEVELS. HOWEVER, ACTIVE
PERIODS ARE POSSIBLE DURING THE FIRST TWO DAYS IN RESPONSE TO RECENT
CME OCCURRENCES.
III. Event Probabilities 17 MAR to 19 MAR
| Class M | 50% | 45% | 40% |
| Class X | 05% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 16 MAR 156 Predicted 17 MAR-19 MAR 155/150/145 90 Day Mean 16 MAR 142
V. Geomagnetic A Indices
OBSERVED AFR/AP 15 MAR 011/016 ESTIMATED AFR/AP 16 MAR 005/005 PREDICTED AFR/AP 17 MAR-19 MAR 012/010-015/012-010/008
VI. Geomagnetic Activity Probabilities 17 MAR to 19 MAR
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 30% | 25% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 30% | 35% | 30% |
| Minor storm | 10% | 10% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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