Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 10 Aug 2003

By SpaceRef Editor

August 10, 2003

Filed under Space Weather Prediction Center (NOAA), Space Weather Solar-Geophysical Activity, US

Joint USAF/NOAA Report of Solar and Geophysical Activity 10 Aug 2003

SDF Number 222 Issued at 2200Z on 10 Aug 2003

IA. Analysis of Solar Active Regions and Activity from 09/2100Z
to 10/2100Z: Solar activity was low. Region 425 (S09W43) produced a
C3/Sf flare at 10/1020Z followed by a more gradual C2 flare that
peaked at 10/1128Z. Region 431 (S13E56) produced an impulsive C1/Sf
flare at 10/0127Z. This beta gamma region is showing some minor
complexity in a spot group with over 250 millionths of white light
coverage. Region 424 (S18W41), the largest region on the visible
disk, exhibited only minor plage fluctuations this period. Remaining
active regions were quiet.

IB. Solar Activity Forecast: Solar activity is expected to continue
at low levels. C-class flares are possible from Regions 424, 425,
and 431.

IIA. Geophysical Activity Summary 09/2100Z to 10/2100Z:
The geomagnetic field was quiet to active. A declining high speed
stream with very low density and weak northward IMF Bz continues to
buffet the Earth’s magnetic field. Solar wind speed declined from
near 700 km/s to below 600 km/s by the end of the period. The
greater than 2 MeV electrons at geosynchronous orbit reached high
levels again today.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be mostly quiet to active on day one. Another coronal
hole high speed stream is expected to impact the geomagnetic field
on days two and three. Expect unsettled to minor storm levels both
days with isolated major storm periods on day three.

III. Event Probabilities 11 Aug-13 Aug