Viewing archive of Tuesday, 12 October 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 Oct 12 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 285 Issued at 2200Z on 12 OCT 1999

IA. Analysis of Solar Active Regions and Activity from 11-2100Z to 12-2100Z

SOLAR ACTIVITY WAS LOW. REGION 8731 (N10E49) PRODUCED MOST OF TODAY'S LOW LEVEL SUBFLARE ACTIVITY. THE REGION ROTATED MORE FULLY INTO VIEW AS A MODERATE SIZED D-TYPE GROUP. REGION 8728 (N22E25) CONTINUES TO BE THE LARGEST REGION ON THE DISK BUT WAS FAIRLY STABLE, EXHIBITING ONLY OCCASIONAL POINT BRIGHTENINGS. NEW REGION 8732 (N20E41) WAS ASSIGNED TODAY.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW. THERE IS, HOWEVER, A CHANCE FOR AN ISOLATED M-CLASS EVENT FROM EITHER REGION 8728 OR 8731.
IIA. Geophysical Activity Summary 11-2100Z to 12-2100Z
THE GEOMAGNETIC FIELD RANGED FROM UNSETTLED TO MINOR STORM LEVELS, WITH AN INTERVAL OF MAJOR STORM AT HIGH LATITUDES FROM 0900-1200Z. AN INITIALLY ACTIVE LEVEL DISTURBANCE STRENGTHENED TO MOSTLY MINOR STORM LEVELS FROM 0000-1200Z. CONDITIONS APPEARED TO BE SUBSIDING DURING THE LAST NINE HOURS OF THE REPORTING INTERVAL (1200-2100Z), WITH MID-LATITUDES ATTAINING UNSETTLED AND HIGH LATITUDES AT ACTIVE TO MINOR STORM. THE GREATER THAN 2 MEV ELECTRON FLUXES ATTAINED HIGH LEVELS DURING THE PAST 24 HOURS.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS EXPECTED TO BE ACTIVE AT MID-LATITUDES AND ACTIVE TO MINOR STORM AT HIGH LATITUDES DURING THE NEXT THREE DAYS. THE INCREASE IS EXPECTED AS A RESULT OF EARTH'S INTERACTION WITH A HIGH-SPEED SOLAR-WIND STREAM FROM A FAVORABLY POSITIONED CORONAL HOLE.
III. Event Probabilities 13 OCT to 15 OCT
Class M30%30%30%
Class X05%05%05%
Proton05%05%05%
PCAFGREEN
IV. Penticton 10.7 cm Flux
  Observed       12 OCT 184
  Predicted   13 OCT-15 OCT  185/190/190
  90 Day Mean        12 OCT 155
V. Geomagnetic A Indices
OBSERVED AFR/AP 11 OCT  018/023
ESTIMATED AFR/AP 12 OCT  027/034
PREDICTED AFR/AP 13 OCT-15 OCT  020/030-020/030-020/025
VI. Geomagnetic Activity Probabilities 13 OCT to 15 OCT
A. Middle Latitudes
Active45%45%45%
Minor storm15%15%15%
Major-severe storm10%10%10%
B. High Latitudes
Active40%40%40%
Minor storm20%20%20%
Major-severe storm10%10%10%

All times in UTC

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