Status Report

NOAA/USAF Report of Solar-Geophysical Activity 5 October 2000

By SpaceRef Editor
October 5, 2000
Filed under
:Product: Report of Solar-Geophysical Activity
:Issued: 2000 Oct 05 2200 UT
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
#Space Environment Center and the U.S. Air Force.
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 279 Issued at 2200Z on 05 Oct 2000
IA.  Analysis of Solar Active Regions and Activity from  04/2100Z
to 05/2100Z:  Solar activity was low. Today's largest event was a
C2/1f flare at 0613Z from Region 9172 (N13W73). Region 9173 (S13W68)
is currently the largest region on the disk but is stable and in a
state of slow decline.
IB.  Solar Activity Forecast:  Solar activity is expected to be low
to moderate.
IIA.  Geophysical Activity Summary 04/2100Z to 05/2100Z:
The geomagnetic field ranged from active to severe storm levels
(estimated Kp of 7). A strong shock was observed at the ACE
spacecraft at 0241Z, and was followed by transient flow with
enhanced density, speed, and magnetic fields. Major to severe
storming at all latitudes began after 0300Z. There were two
intervals of strongly negative Bz: the first was from 0504-0543Z
with Bz values reaching -27 nT and the second was from 0958-1119Z
with Bz values reaching -23 nT. Severe (estimated Kp of 7) levels
were seen at high latitudes from 0300-1500Z and mid-latitudes also
attained the K=7 level from 0600-0900Z. The disturbance appeared to
be subsiding during the last three hours of the day.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be at active to minor storm levels during the next 24
hours as the current disturbance subsides. Unsettled to active
conditions should follow on the 2nd day, and predominantly unsettled
levels are expected by day three.
III.  Event Probabilities 06 Oct-08 Oct
Class M    30/30/30
Class X    05/05/05
Proton     05/05/05
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           05 Oct 174
Predicted   06 Oct-08 Oct  170/160/150
90 Day Mean        05 Oct 184
V.  Geomagnetic A Indices
Observed Afr/Ap 04 Oct  025/045
Estimated Afr/Ap 05 Oct  075/085
Predicted Afr/Ap 06 Oct-08 Oct  025/035-015/015-012/010
VI.  Geomagnetic Activity Probabilities 06 Oct-08 Oct
A.  Middle Latitudes
Active                25/35/20
Minor storm           50/30/15
Major-severe storm    20/05/05
B.  High Latitudes
Active                25/35/25
Minor storm           45/30/20
Major-severe storm    25/10/05

SpaceRef staff editor.