[Ips-dsgr] ASWFC Daily Report - 15 September 26 issued 2330 UT on 15 Sep 2026 [SEC=OFFICIAL]
Australian Space Weather Forecasting Centre
aswfc at bom.gov.au
Wed Sep 16 09:30:50 AEST 2026
SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/15 SEPTEMBER 2026
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 15 SEPTEMBER AND FORECAST FOR 16 SEPTEMBER - 18 SEPTEMBER
STATUS INDICATORS SOL:GREEN MAG:** YELLOW ** ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 15 Sep: R0
Flares: none.
Observed 10.7 cm flux/Equivalent Sunspot Number for 15 Sep: 107/57
1B. SOLAR FORECAST
16 Sep 17 Sep 18 Sep
Activity R0 R0 R0
Fadeouts None expected None expected None expected
10.7cm/SSN 110/60 105/54 100/48
COMMENT: Solar flare activity on UT day 15-Sep was at the R0
level, with no notable solar flares. There are currently four
numbered sunspot regions and one unnumbered region visible on
the solar disk. All numbered regions are small and magnetically
simple. An unnumbered region has developed on the solar disk
at around N08E45 with beta magnetic classification. Solar flare
activity is expected to be at the R0 level over 16-18 Sep. The
>10 MeV proton flux as measured at GOES was elevated below the
S1 threshold on 15-Sep, but declined to background levels over
the day. S0 conditions are expected over 16-18 Sep. No CMEs were
observed on 15-Sep. A coronal hole in the southern hemisphere
appears to not have affected the solar wind environment at Earth.
The solar wind speed increased slightly over the day, with two
periods of high speed spikes. The solar wind speed mostly ranged
between 340 km/s and 515 km/s and is currently near 450 km/s,
with the speed spikes reaching just below 800 km/s. The IMF was
enhanced over the UT day. The peak total field strength (Bt)
was 16 nT the north-south IMF component range (Bz) was +13 to
-13 nT. A coronal hole in the northern hemisphere is expected
to become geoeffective on 16-Sep, in addition, a pair of recently
observed CMEs are expected to produce a glancing impact at Earth
on 16-Sep late in the UT day. As a result, the solar wind speed
is expected to increase on 16-Sep and remain elevated over 17-18
Sep.
-----------------------------------------------------------
2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 15 Sep: G0
Estimated Indices 15 Sep : A K
Australian Region 7 33102023
Cocos Island 8 33212023
Darwin 8 33102123
Townsville 8 33202023
Learmonth 8 33102123
Alice Springs 7 331-2022
Gingin 6 32101123
Canberra 6 23202022
Kennaook Cape Grim 7 33002023
Hobart 6 23002023
Estimated Antarctic Regional K Indices 15 Sep :
Casey 21 35323344
Mawson 26 63112046
Observed Regional daily pc3 Indices 15 Sep :
Darwin 0 (Quiet)
Townsville 0 (Quiet)
Learmonth 4 (Quiet)
Alice Springs 15 (Quiet)
Gingin 2 (Quiet)
Canberra 4 (Quiet)
Hobart 0 (Quiet)
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.
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.
Estimated AFr/Ap Indices 15 Sep : A
Fredericksburg 10
Planetary 14
Observed AFr/Ap Indices 14 Sep : A K
Fredericksburg 8
Planetary 11 1212 3433
2B. MAGNETIC FORECAST
Date Ap Conditions
16 Sep 22 G1, chance of G2
17 Sep 16 G0 - G1
18 Sep 10 G0
COMMENT: G0 geomagnetic conditions were observed at the planetary
level and in the Australian region on UT day 14-Sep. G0-G2 conditions
were observed in the Antarctic region. G1 conditions, with a
chance of G2 are expected on 16-Sep due to anticipated high speed
wind stream effects from a coronal hole in the northern hemisphere,
combined with a glancing CME impact late in the day. G0-G1 conditions
are expected on 17-Sep due to ongoing effects. Conditions are
expected to return to G0 by 18-Sep.
-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
Latitude Band
Date Low Middle High
15 Sep Normal-fair Normal-fair Normal-fair
PCA Event : No event.
3B. GLOBAL HF PROPAGATION FORECAST
Latitude Band
Date Low Middle High
16 Sep Normal Normal-fair Fair
17 Sep Normal Normal-fair Fair
18 Sep Normal Normal Normal-fair
COMMENT: HF radio propagation conditions on UT day 15-Sep were
mostly normal, with mildly degraded conditions observed in the
northern hemisphere over the UT day. HF radio propagation conditions
may become degraded over 16-17 Sep due to anticipated geomagnetic
activity over the period, with the strongest degradations expected
at high latitudes. HF radio propagation conditions are expected
to be mostly normal on 18-Sep.
-----------------------------------------------------------
4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date T index
15 Sep 70
Observed Australian Regional MUFs
Cocos Island Region:
No data available during local day.
No data available during local night.
Niue Island Region:
Enhanced by 30% during local day.
Enhanced by 15% during local night.
Northern Australian Region:
Near predicted monthly values during local day.
Enhanced by 15% during local night.
Southern Australian Region:
Near predicted monthly values.
Antarctic Region (Casey/Davis/Mawson):
Near predicted monthly values over the UT day.
Monthly T index:
Month T index
Aug 66
Sep 62
Oct 60
4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date T index MUFs
16 Sep 50 Near predicted monthly values/depressed 5 to
15%
17 Sep 55 Near predicted monthly values/depressed 5 to
15%
18 Sep 65 Near predicted monthly values
COMMENT: Maximum usable frequencies (MUFs) in the Australian
region on UT day 15-Sep were near predicted monthly values, with
enhanced conditions observed in the northern Australian region
during local night hours. Spread F was observed at Hobart during
local night hours. MUFs are expected to be near predicted monthly
values to depressed by up to 15% over 16-17 Sep, due to anticipated
geomagnetic activity. Depressions are more likely in the southern
Australian region. MUFs are expected to be near predicted monthly
values on 18-Sep.
-----------------------------------------------------------
5. SPACE ENVIRONMENT SUMMARY
GOES satellite data for 14 Sep
Daily Proton Fluence >1 MeV: 9.3E+06
Daily Proton Fluence >10 MeV: 1.9E+05
Daily Electron Fluence >2 MeV: 1.10E+08 (moderate fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability:11%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
X-ray background: B2.7
Solar Wind Day Averaged Data for 14 Sep
Speed: 346 km/sec Density: 6.3 p/cc Temp: 72500 K Bz: 0 nT
(Courtesy Space Weather Prediction Center, Boulder USA)
-----------------------------------------------------------
Australian Space Weather Forecasting Centre
Bureau of Meteorology
ASWFC at bom.gov.au
www.bom.gov.au | www.sws.bom.gov.au
More information about the ips-dsgr
mailing list