[Ips-dsgr] ASWFC Daily Report - 24 August 26 issued 2330 UT on 24 Aug 2026 [SEC=OFFICIAL]

Tue Aug 25 09:30:50 AEST 2026

SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/24 AUGUST 2026
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 24 AUGUST AND FORECAST FOR 25 AUGUST - 27 AUGUST
STATUS INDICATORS SOL:** YELLOW **   MAG:GREEN     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 24 Aug:  R1

Flares    Max     Fadeout    Freq.  Sectors
  M1.7    1937UT  possible   lower  East Pacific/
                                    North American

Observed 10.7 cm flux/Equivalent Sunspot Number for 24 Aug: 143/97

1B. SOLAR FORECAST
             25 Aug             26 Aug             27 Aug
Activity     R1, chance of R2   R1, chance of R2   R1, chance of R2
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   140/94             140/94             138/92

COMMENT: Solar flare activity on UT day 24-Aug was at the R1 
level due to an M1.7 flare at 24/1936UT produced by Active Region 
(AR) 4513 (N04E17, gamma-delta). There are currently four numbered 
sunspot regions visible on the solar disk. AR 4513 is the largest 
and most magnetically complex region on the disk and has exhibited 
spot development over the UT day. This region contains multiple 
delta spots and has become increasingly compact over the past 
24 hours. Regions 4516 (N16W54, beta) and 4517 (N09E02, beta) 
have both shown spot growth over the UT day. Region 4515 (S08E26, 
alpha) is simple and stable. Solar flare activity is expected 
to be at the R1 level over 25-27 Aug, with a chance of R2 due 
to the magnetic complexity of region 4513. S0 solar radiation 
storm conditions were observed on UT day 24-Aug, though the proton 
flux remained elevated. S0 solar radiation storm conditions are 
expected over 25-27 Aug, with a chance of S1 due to the current 
elevated proton flux. No Earth-directed coronal mass ejections 
(CMEs) have been observed. The solar wind speed on UT day 24-Aug 
declined, ranging between 400 and 330 km/s, and is currently 
near 355 km/s. The peak total interplanetary magnetic field strength 
(IMF, Bt) was 7 nT and the north-south IMF component (Bz) range 
was -4 to +4 nT. The solar wind speed is expected to remain at 
background levels over 25-26 Aug. A southern hemisphere coronal 
hole is currently crossing the central meridian and is expected 
to influence the solar wind speed on 27-Aug, though its effects 
will be limited by its far-southern latitudinal extent.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 24 Aug: G0

Estimated Indices 24 Aug : A   K           
   Australian Region       2   11100002
      Cocos Island         1   11010001
      Darwin               2   11110012
      Townsville           2   12100012
      Learmonth            2   20110012
      Alice Springs        2   11100002
      Gingin               1   10100001
      Canberra             1   11000001
      Kennaook Cape Grim   1   11000002
      Hobart               1   01000002    

Estimated Antarctic Regional K Indices 24 Aug :
      Casey                4   22210112
      Mawson              11   43110034

Observed Regional daily pc3 Indices 24 Aug : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            4   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin               0   (Quiet)
      Canberra             0   (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 24 Aug : A 
           Fredericksburg         5
           Planetary              5                         

Observed AFr/Ap Indices 23 Aug :  A   K
           Fredericksburg         6
           Planetary              6   1222 2122     

2B. MAGNETIC FORECAST 
Date      Ap    Conditions
25 Aug     4    G0
26 Aug     4    G0
27 Aug    10    G0

COMMENT: G0 geomagnetic conditions were observed in the planetary, 
Australian and Antarctic regions on UT day 24-Aug. G0 planetary 
geomagnetic conditions are expected over 25-27 Aug.

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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
24 Aug      Normal-fair    Normal         Normal         

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
25 Aug      Normal         Normal         Normal
26 Aug      Normal         Normal         Normal
27 Aug      Normal         Normal         Normal-fair

COMMENT: HF radio propagation conditions on UT day 24-Aug were 
mostly normal, with some mild degradations observed at low latitudes 
over the day. HF radio propagation conditions are expected to 
be mostly normal over 25-27 Aug. Shortwave fadeouts are possible.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY

Date   T index
24 Aug    79

Observed Australian Regional MUFs
   Cocos Island Region:
      No data available during local day.
      No data available during local night.
   Niue Island Region:
      No data available during local day.
      No data available during local night.
   Northern Australian Region:
      Near predicted monthly values.
   Southern Australian Region:
      Near predicted monthly values during local day.
      Enhanced by 15% during local night.
      Enhanced by 20% after local dawn.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

Monthly T index:
Month  T index
Jul      75
Aug      64
Sep      61

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
25 Aug    80    Near to 15% above predicted monthly values
26 Aug    80    Near to 15% above predicted monthly values
27 Aug    75    Near predicted monthly values

COMMENT: ASWFC SWF HF Communications Warning 76 was issued on 
22 August and is current for 23-25 Aug. Maximum usable frequencies 
(MUFs) in the Australian region on UT day 24-Aug were near predicted 
monthly values, with enhancements observed in the southern Australian 
region. Spread F was observed at Perth during local night hours. 
MUFs are expected to be near predicted monthly values to 15% 
enhanced over 25-26 Aug, then near predicted monthly values on 
27-Aug. Shortwave fadeouts are possible.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 23 Aug
       Daily Proton Fluence >1 MeV:   2.2E+06
       Daily Proton Fluence >10 MeV:  2.9E+05
       Daily Electron Fluence >2 MeV: 9.00E+07   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability:10%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: B7.3

Solar Wind Day Averaged Data for 23 Aug
Speed: 416 km/sec  Density:    3.3 p/cc  Temp:   125000 K  Bz:   0 nT

(Courtesy Space Weather Prediction Center, Boulder USA)
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Australian Space Weather Forecasting Centre
Bureau of Meteorology
ASWFC at bom.gov.au
www.bom.gov.au | www.sws.bom.gov.au