[Ips-dsgr] ASWFC Daily Report - 23 June 26 issued 2330 UT on 23 Jun 2026 [SEC=OFFICIAL]

Wed Jun 24 09:30:52 AEST 2026

SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/23 JUNE 2026
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 23 JUNE AND FORECAST FOR 24 JUNE - 26 JUNE
STATUS INDICATORS SOL:** YELLOW **   MAG:** YELLOW **     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 23 Jun:  R0

Flares: none.

Observed 10.7 cm flux/Equivalent Sunspot Number for 23 Jun: 130/84

1B. SOLAR FORECAST
             24 Jun             25 Jun             26 Jun
Activity     R0, chance R1      R1, chance R2      R1, chance R2
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   130/84             135/89             135/89

COMMENT: Solar flare activity on UT day 23-Jun remained at R0. 
There are currently five numbered sunspot regions on the solar 
disk. Active Region (AR) 4476 (N08E13, beta) is the newest, appearing 
early on 22-Jun. The region has seen a growth in the number and 
size of spots over the past 24 hours. AR 4474 has since left 
the solar disk. AR 4470 has largely decayed. A new region also 
appears to be developing at S13E70, but is currently unnumbered. 
A notable region, which has been imaged by Solar Orbiter on the 
Sun's farside is due to rotate on disk within the next 24 hours. 
All other regions are either stable or in decay. Solar flare 
activity is expected to be R0, chance R1 on 24 Jun, increasing 
to R1, chance R2 over 25-26 Jun, given the above mentioned region 
about to rotate onto disk. A CME was observed on LASCO imagery 
at 1900 on 23-Jun. Further analysis is pending additional data 
from STEREO-A. It does not appear to be associated with any front-side 
flares. No Earth-directed CMEs were observed on 23-Jun, with 
the caveat that the previously mentioned CME remains under analysis. 
S0 solar radiation storm conditions were observed on UT day 23-Jun. 
S0 solar radiation storm conditions are expected over 24-26 Jun. 
The solar wind environment on UT day 23-Jun was near background 
levels. The solar wind speed ranged between approximately 330 
to 400 km/s. It is currently 390 km/s. The peak total interplanetary 
field strength (IMF, Bt) was +10 to +1 nT. The north-south IMF 
component (Bz) was +6 to -7 nT. The solar wind speed is expected 
to increase over the 24-26 Jun, due to several coronal holes 
become geoeffective.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 23 Jun: G0

Estimated Indices 23 Jun : A   K           
   Australian Region       2   00012120
      Cocos Island         3   00021030
      Darwin               3   10012121
      Townsville           3   01012221
      Learmonth            3   00112220
      Alice Springs        2   00012020
      Gingin               2   20002020
      Canberra             2   00002120
      Kennaook Cape Grim   3   00012220
      Hobart               2   00012210    

Estimated Antarctic Regional K Indices 23 Jun :
      Macquarie Island     3   00003220
      Casey                6   22112131
      Mawson               9   31102243

Observed Regional daily pc3 Indices 23 Jun : 
      Darwin              NA
      Townsville           0   (Quiet)
      Learmonth            4   (Quiet)
      Alice Springs        6   (Quiet)
      Gingin               7   (Quiet)
      Canberra             8   (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 23 Jun : A 
           Fredericksburg         5
           Planetary              7                         

Observed AFr/Ap Indices 22 Jun :  A   K
           Fredericksburg         5
           Planetary              5   1112 1122     

2B. MAGNETIC FORECAST 
Date      Ap    Conditions
24 Jun    12    G0
25 Jun    12    G0, chance G1
26 Jun    19    G1

COMMENT: G0 geomagnetic conditions were observed in the Australian 
and Antarctic regions on UT day 23-Jun. G0 geomagnetic conditions 
are expected over 24-Jun. There is a chance for an isolated period 
of G1 on 25-Jun due to coronal hole activity, with G1 conditions 
likely on 26-Jun as more coronal holes become geoeffective.

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

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
24 Jun      Normal         Normal         Normal
25 Jun      Normal         Normal         Normal-fair
26 Jun      Normal         Normal-fair    Fair

COMMENT: HF radio propagation conditions on UT day 23-Jun were 
mostly normal. HF radio propagation conditions are expected to 
be normal over 24-Jun, but become mildly degraded by 25-Jun, 
continuing through 26-Jun due to intermittent coronal hole connections 
with Earth.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY

Date   T index
23 Jun    76

Observed Australian Regional MUFs
   Cocos Island Region:
      No data available during local day.
      No data available during local night.
   Niue Island Region:
      Near predicted monthly values.
   Northern Australian Region:
      Near predicted monthly values during local day.
      Enhanced by 25% 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
May      67
Jun      68
Jul      65

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
24 Jun    68    Near predicted monthly values
25 Jun    65    Near predicted monthly values
26 Jun    60    Near predicted monthly values

COMMENT: Maximum usable frequencies (MUFs) in the Australian 
region on UT day 23-Jun were mostly near predicted values, with 
enhancements of up to 25% seen in the Northern Australian region 
during local night. Spread-F was observed over much of the Australian 
region during local night hours. MUFs are expected to be mostly 
near predicted monthly values over 24-26 Jun.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 22 Jun
       Daily Proton Fluence >1 MeV:   4.2E+05
       Daily Proton Fluence >10 MeV:  1.7E+04
       Daily Electron Fluence >2 MeV: 2.70E+07   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 4%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: B6.2

DSCOVR Satellite Solar Wind Day Averaged Data for 22 Jun
Speed: 351 km/sec  Density:    5.2 p/cc  Temp:    46700 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