[Ips-dsgr] ASWFC Daily Report - 10 April 26 issued 2330 UT on 10 Apr 2026 [SEC=OFFICIAL]
Australian Space Weather Forecasting Centre
aswfc at bom.gov.au
Sat Apr 11 09:30:49 AEST 2026
SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/10 APRIL 2026
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 10 APRIL AND FORECAST FOR 11 APRIL - 13 APRIL
STATUS INDICATORS SOL:GREEN MAG:** YELLOW ** ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 10 Apr: R0
Flares: none.
Observed 10.7 cm flux/Equivalent Sunspot Number for 10 Apr: 94/40
1B. SOLAR FORECAST
11 Apr 12 Apr 13 Apr
Activity R0 R0 R0
Fadeouts None expected None expected None expected
10.7cm/SSN 92/37 90/34 90/34
COMMENT: Solar flare activity was at the R0 level on UT day 10-Apr.
No significant flare activity was observed. There is currently
no region of significance on the visible solar disk. A small
solar region AR4416 (N19E17, beta) emerged on disk and rapidly
grew, though this initial rapid growth rate may not be sustained.
Small solar region AR4414 (N13E41, beta) is decaying. There are
currently three numbered solar regions on the visible solar disk.
The other solar region is a stable monopole. Solar activity is
expected to be at the R0 level for 11-13 Apr. S0 solar radiation
storm conditions were observed on 10-Apr. S0 solar radiation
storm conditions are expected over 11-13 Apr. No Earth directed
coronal mass ejections (CMEs) were observed. A very minor faint
narrow westward CME was observed from 10/0449UT that could not
be correlated to the solar disk. Three isolated coronal holes
are now located west of the solar central meridian and the Earth
entered a coronal hole wind stream from 10/0305UT. The solar
wind speed gradually increased from light to strong on 10-Apr,
ranging from 373 to 662 km/s and is currently at 599 km/s. The
peak total interplanetary magnetic field strength (IMF, Bt) was
11 nT and the north-south component (Bz) range was -9 and +11
nT. An interval of mildly southward IMF conditions was observed
10/1100-1300UT. The solar wind speed is expected to be strong
on 11-12 Apr due to the influence of the solar coronal hole wind
stream.
-----------------------------------------------------------
2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 10 Apr: G0
Estimated Indices 10 Apr : A K
Australian Region 13 32324331
Cocos Island 10 32323231
Darwin 13 33323332
Townsville 13 33324321
Learmonth 13 32324331
Alice Springs 13 32324331
Gingin 12 32314331
Canberra 10 22314321
Kennaook Cape Grim 11 22314331
Hobart 10 22314321
Estimated Antarctic Regional K Indices 10 Apr :
Macquarie Island 22 32226531
Casey 18 34523331
Mawson 36 64424463
Observed Regional daily pc3 Indices 10 Apr :
Darwin 7 (Quiet)
Townsville 4 (Quiet)
Learmonth 0 (Quiet)
Alice Springs 4 (Quiet)
Gingin 9 (Quiet)
Canberra 31 (Quiet to unsettled)
Hobart 43 (Unsettled)
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 10 Apr : A
Fredericksburg 19
Planetary 22
Observed AFr/Ap Indices 09 Apr : A K
Fredericksburg 6
Planetary 7 2121 2222
2B. MAGNETIC FORECAST
Date Ap Conditions
11 Apr 18 G0-G1
12 Apr 16 G0, chance G1
13 Apr 11 G0
COMMENT: ASWFC Geomagnetic Warning 27 was issued on 10 April
and is current for 11 Apr only. G0 geomagnetic conditions were
observed in the Australian region on 10-Apr. G1-G2 geomagnetic
periods were observed in the Antarctic region. G0 with G1 periods
are expected over 11-12 Apr due to a coronal hole high speed
wind stream.
-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
Latitude Band
Date Low Middle High
10 Apr Normal Fair-normal Poor-fair
PCA Event : No event.
3B. GLOBAL HF PROPAGATION FORECAST
Latitude Band
Date Low Middle High
11 Apr Normal Fair-normal Poor-fair
12 Apr Normal Fair-normal Fair
13 Apr Normal Normal Fair-normal
COMMENT: HF radio propagation conditions on 10-Apr were poor
at times at high latitudes and fair to normal at middle latitudes.
Mildly increased ionospheric absorption were observed on the
Macquarie Island riometer during the intervals 10/0200-0600UT
and 10/1300-1600UT. Generally fair to normal HF conditions are
expected on 11-12 Apr, with periods of poor to fair conditions
at high latitudes due to mild geomagnetic activity. High latitude
HF conditions are expected to improve on 13-Apr.
-----------------------------------------------------------
4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date T index
10 Apr 79
Observed Australian Regional MUFs
Cocos Island Region:
Enhanced by 15% during local day.
Near predicted monthly values during local night.
Niue Island Region:
Mostly near predicted monthly values.
Northern Australian Region:
Enhanced by 15% during local day.
Depressed by 15-20% during local night.
Southern Australian Region:
Near predicted monthly values.
Antarctic Region (Casey/Davis/Mawson):
Depressed by 30% over the UT day.
Monthly T index:
Month T index
Mar 92
Apr 83
May 81
4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date T index MUFs
11 Apr 70 Depressed 10 to 15%/near predicted monthly values
12 Apr 80 Depressed 10 to 15%/near predicted monthly values
13 Apr 90 Near predicted monthly values
COMMENT: Maximum Usable Frequencies (MUFs) in the Australian
region were generally near predicted monthly values on 10-Apr.
Northern Australian region MUFs were depressed by up to 20% at
times during local night hours. Spread F was observed at Hobart
during local night hours. MUFs are generally expected to be near
predicted monthly values over 11-13 Apr for the northern Australian
region with brief 15% depressions after local dawn for the southern
Australian region during 11-12 Apr due to mild geomagnetic activity
induced by a coronal hole wind stream.
-----------------------------------------------------------
5. SPACE ENVIRONMENT SUMMARY
GOES satellite data for 09 Apr
Daily Proton Fluence >1 MeV: 8.1E+05
Daily Proton Fluence >10 MeV: 1.8E+04
Daily Electron Fluence >2 MeV: 3.30E+08 (moderate fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability:19%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
X-ray background: B3.9
DSCOVR Satellite Solar Wind Day Averaged Data for 09 Apr
Speed: 373 km/sec Density: 2.1 p/cc Temp: 59900 K Bz: -2 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