Viewing archive of Thursday, 11 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 11 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 070 Issued at 2200Z on 11 MAR 1999IA. Analysis of Solar Active Regions and Activity from 10-2100Z to 11-2100Z
SOLAR ACTIVITY WAS LOW. REGION 8483 (S18W61) SHOWED
GROWTH AND FREQUENT SMALL FLARE ACTIVITY, INCLUDING A C8/SF AT
0009Z. NEW REGION 8487 (N17E63) WAS ALSO ACTIVE TODAY AND PRODUCED A
C6/SF AT 2034Z. REGION 8485 (N22E27) GREW SLOWLY AND IS CURRENTLY
THE LARGEST SUNSPOT GROUP ON THE DISK, BUT COULD ONLY MUSTER A
COUPLE SUBFLARES.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW.
THERE IS A SLIGHT CHANCE FOR AN ISOLATED M-CLASS EVENT, HOWEVER,
FROM ANY OF REGIONS 8485, 8484 OR 8483.
IIA. Geophysical Activity Summary 10-2100Z to 11-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO ACTIVE. AN INITIALLY QUIET FIELD
BECAME MOSTLY UNSETTLED AFTER 11/0000Z AND CONTINUED UNSETTLED
THROUGH THE END OF THE DAY, WITH THE EXCEPTION OF AN ISOLATED ACTIVE
PERIOD AT HIGH LATITUDES BETWEEN 1200-1500Z.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE MOSTLY UNSETTLED FOR THE NEXT 36 TO 48 HOURS. THERE
IS A FAIR CHANCE FOR AN INCREASE TO ACTIVE LEVELS BEGINNING LATE ON
THE 13TH OR PERHAPS ON THE 14TH AS A RESPONSE TO YESTERDAY'S
FILAMENT ERUPTION. NOTE ALSO THAT THERE IS ALSO AN ENHANCED,
PROBABILITY FOR STORM LEVEL CONDITIONS DURING THIS TIME FRAME.
III. Event Probabilities 12 MAR to 14 MAR
| Class M | 20% | 20% | 20% |
| Class X | 05% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 11 MAR 137 Predicted 12 MAR-14 MAR 140/140/135 90 Day Mean 11 MAR 142
V. Geomagnetic A Indices
OBSERVED AFR/AP 10 MAR 029/031 ESTIMATED AFR/AP 11 MAR 013/015 PREDICTED AFR/AP 12 MAR-14 MAR 010/012-015/015-020/023
VI. Geomagnetic Activity Probabilities 12 MAR to 14 MAR
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 30% | 35% |
| Minor storm | 10% | 15% | 25% |
| Major-severe storm | 05% | 10% | 15% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 30% | 35% |
| Minor storm | 10% | 20% | 25% |
| Major-severe storm | 05% | 15% | 20% |
All times in UTC
Current data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future
Yellowknife, NTFairbanks, AK
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