[Ips-wgr] ASWFC Weekly Geo. Report (11 September 25) issued 0203 UT on 11 Sep 2025 [SEC=OFFICIAL]

[Australian Space Weather Forecasting Centre]

SUBJ: ASWFC WEEKLY GEOPHYSICAL REPORT 
ISSUED ON 11 SEPTEMBER 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx

1. SUMMARY (02 SEPTEMBER - 10 SEPTEMBER)
K indices are in UT (0-24). For conversion to local time:

AEST = UT + 10 hours; ACST = UT + 9.5 hours; AWST = UT + 8 hours
        Australian Region*              
 Date     K-INDICES    A               
 02 Sep   5454 3454   33  
 03 Sep   2222 1021    5  
 04 Sep   2112 2323    8  
 05 Sep   1112 1123    5  
 06 Sep   2333 4431   15  In the BOM magnetometer data for 06 
                          Sep, a weak (20nT) impulse was observed 
                          at 1424UT.
 07 Sep   0000 0012    1  
 08 Sep   3323 3322   12  
 09 Sep   2222 2224    9  
 10 Sep   2211 2312    6  

*estimated from real time data

NOTE: Indices may have been generated from data obtained in 
cooperation with the following organisations: Geoscience Australia, 
University of Newcastle Space Physics Group, Australian Government 
Antarctic Division and International Center for Space Weather 
Science and Education, Japan.


G1 periods were observed on 02-Sep in the Australian regional
and planetary geomagnetic field. Geomagnetic activity over the UT 
day was due to the arrival of a halo CME late on 01-Sep. On 
06-Sep planetary conditions reached G1 due to a coronal hole wind
stream, with the Australian regional field remaining at G0.


2. FORECAST (11 SEPTEMBER - 11 OCTOBER)
Disturbed Periods: 
15-16 Sep, 03-Oct, 06-07 Oct, 12-13 Oct.

Best Quiet Periods: 
12-13 Sep, 19-20 Sep , 24-25 Sep.

3. FORECAST FOR HIGH RESOLUTION AEROMAGNETIC SURVEYS
Northern Australian Regions:
 Disturbed Periods: None.
 Best Quiet Periods: 11-15 Sep, 19-28 Sep, 07-11 Oct.

Central Australian Regions: NA

Southern Australian Regions:
 Disturbed Periods: 16-Sep, 18-Sep, 03-05 Oct.
 Best Quiet Periods: 11-14 Sep,  20-27 Sep,  30-Sep to 01-Oct, 09-11 Oct.


Pc3 pulsations are high frequency (10-45 second period) variations 
of the Earths magnetic field. Daily pc3-indices are the daily sum of 
20 minute pc3-indices for that station and have been shown to be well 
correlated with rejection of high resolution aeromagnetic survey 
flight-line data.

PLEASE NOTE:
Geomagnetic activity can frequently be determined by short timescale 
solar events that cannot be forecast a week in advance, particularly
at solar maximum.

Australian Space Weather Forecasting Centre
Bureau of Meteorology
ASWFC at bom.gov.au
www.bom.gov.au | www.sws.bom.gov.au