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Viewing archive of Wednesday, 28 July 1999

Solar activity report

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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 Jul 28 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 209 Issued at 2200Z on 28 JUL 1999

IA. Analysis of Solar Active Regions and Activity from 27-2100Z to 28-2100Z

SOLAR ACTIVITY WAS MODERATE. REGION 8649 (S15W05) PRODUCED AN M1/SF AT 28/0201Z. THIS EVENT WAS ACCOMPANIED BY A TYPE IV SWEPT FREQUENCY BURST, AND A 450 SFU BURST AT 10CM. THIS REGION ALSO PRODUCED A M2/1B AT 28/0814Z. REGION 8645 (S26E22) PRODUCED A C7/1N AT 28/1812Z WITH A TYPE II SWEPT FREQUENCY BURST WITH A SPEED ESTIMATED AT 500 KM/S. TWO NEW REGIONS WERE NUMBERED TODAY AS REGION 8652 (N17W37) AND REGION 8653 (N28W30).
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW TO MODERATE WITH A CHANCE FOR AN ISOLATED X-CLASS EVENT CONSIDERING THE CURRENT REGIONS ON THE SUN.
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO ACTIVE.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS EXPECTED TO BE QUIET TO UNSETTLED THROUGH THE FORECAST PERIOD.
III. Event Probabilities 29 JUL to 31 JUL
Class M80%80%80%
Class X15%15%15%
Proton15%15%15%
PCAFGREEN
IV. Penticton 10.7 cm Flux
  Observed       28 JUL 198
  Predicted   29 JUL-31 JUL  190/190/185
  90 Day Mean        28 JUL 159
V. Geomagnetic A Indices
OBSERVED AFR/AP 27 JUL  006/006
ESTIMATED AFR/AP 28 JUL  012/012
PREDICTED AFR/AP 29 JUL-31 JUL  008/008-008/008-005/005
VI. Geomagnetic Activity Probabilities 29 JUL to 31 JUL
A. Middle Latitudes
Active15%15%15%
Minor storm05%05%05%
Major-severe storm01%01%01%
B. High Latitudes
Active20%20%15%
Minor storm05%05%05%
Major-severe storm01%01%01%

All times in UTC

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