Viewing archive of Wednesday, 28 July 2004

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.
:Product: 20040728SGAS.txt :Issued: 2004 Jul 28 0250 UT Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Solar and Geophysical Activity Summary

SGAS Number 210 Issued at 0245Z on 28 Jul 2004 This report is compiled from data received at SWO on 27 Jul
A. Energetic Events
Begin  Max  End  Rgn   Loc   Xray  Op 245MHz 10cm   Sweep
 0523 0523 0523                       130                           
 0541 0545 0552  0652 N02W53 M1.1  1n 320    100                    
 0556 0556 0556                       930                           
 1127 1128 1128                       100                           
 1959 2020 2037  0652 N09W65 M1.5  1f                               
 2346 0000 0011  0652 N10W54 M1.2  1f                               
B. Proton Events
The greater than 10 MeV proton event that began on 25/1855Z is still in progress. A rapid, short-lived increase in the greater than 10 MeV protons to 2,090 pfu occurred with the shock passage at 25/2250Z. Protons quickly declined and were straddling the 10 pfu alert threshold by the end of the period.
C. Geomagnetic Activity Summary
The geomagnetic field ranged from active to severe storming. A strong sudden impulse (SI) of 95 nT was observed on the Boulder magnetometer at 26/2228Z. This SI followed the very fast (~31 hours) transit of the full halo CME associated with the long duration M1 flare on 25/1514Z. Solar wind speed increased from the already elevated levels near 600 km/s to over 1050 km/s. After approximately four hours of fluctuating between -15 and +15 nT, the IMF Bz rotated strong southward and ranged from -15 to -25 nT for about 15 hours. The fast solar wind speed and southward Bz combined to produce severe geomagnetic storm levels at all latitudes from 27/0000Z to 27/1500Z. Solar wind speed was still near 900 km/s by the end of the period but Bz was near zero. The disturbance declined to minor storm levels to end the period.
D. Stratwarm
E. Daily Indices: (real-time preliminary/estimated values)
10 cm 118  SSN 066  Afr/Ap 131/162   X-ray Background B4.4
Daily Proton Fluence (flux accumulation over 24 hrs)
GT 1 MeV 2.7e+08   GT 10 MeV 1.9e+06 p/(cm2-ster-day)
(GOES-11 satellite synchronous orbit W97 degrees)
Daily Electron Fluence
GT 2 MeV 9.40e+07 e/(cm2-ster-day)
(GOES-12 satellite synchronous orbit W75 degrees)
3 Hour K-indices
Boulder 7 7 7 8 8 6 4 5 Planetary 8 7 8 8 9 7 5 5 
F. Comments

All times in UTC

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