Viewing archive of Thursday, 16 September 1999
Geophysical 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.
Solar and Geophysical Activity Summary 1999 Sep 16 0245 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Solar and Geophysical Activity Summary
SGAS Number 259 Issued at 0245Z on 16 SEP 1999 This report is compiled from data received at SWO on 15 SEPA. Energetic Events
Begin Max End Rgn Loc Xray Op 245MHz 10cm Sweep 0422 0427 0430 C1.1 450 1049 1050 1050 120 1119 1121 1125 110 2106 2108 2109 8699 N22W20 C1.5 SF 230
B. Proton Events
None
C. Geomagnetic Activity Summary
THE GEOMAGNETIC FIELD RANGED FROM
QUIET TO MINOR STORM LEVELS WITH A PERIOD OF SEVERE STORM LEVELS AT
HIGH LATITUDE. A SUDDEN IMPULSE WAS OBSERVED AT 15/2019Z, MEASURING
8 NT IN BOULDER.
D. Stratwarm
None
E. Daily Indices: (real-time preliminary/estimated values)
10 CM 155 SSN 155 AFR/AP 026/032 X-RAY BACKGROUND B6.9 DAILY PROTON FLUENCE (FLUX ACCUMULATION OVER 24 HRS) GT 1 MEV 4.3E+06 GT 10 MEV 1.6E+04 P/(CM2-STER-DAY) (GOES-8 SATELLITE SYNCHRONOUS ORBIT W75 DEGREES) DAILY ELECTRON FLUENCE GT 2 MEV 4.00E+08 E/(CM2-STER-DAY) (GOES-8 SATELLITE SYNCHRONOUS ORBIT W75 DEGREES) 3 HOUR K-INDICES: BOULDER 4 4 5 5 3 2 2 1 PLANETARY 4 3 5 7 4 3 3 2
F. Comments
THE GREATER THAN 2 MEV ELECTRON FLUENCE ATTAINED MODERATE LEVELS FOR THE 15TH OF SEPTEMBER.
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