[Ips-dsgr] ASWFC Daily Report - 25 July 24 issued 2330 UT on 25 Jul 2024 [SEC=OFFICIAL]

Fri Jul 26 09:30:45 AEST 2024

SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/25 JULY 2024
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 25 JULY AND FORECAST FOR 26 JULY - 28 JULY
STATUS INDICATORS SOL:** YELLOW **   MAG:** YELLOW **     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 25 Jul:  R1

Flares    Max     Fadeout    Freq.  Sectors
  M1.3    1537UT  possible   lower  South American/
                                    Atlantic

Observed 10.7 cm flux/Equivalent Sunspot Number for 25 Jul: 167/121

1B. SOLAR FORECAST
             26 Jul             27 Jul             28 Jul
Activity     R0-R1, chance R2   R0-R1, chance R2   R0-R1, chance R2
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   170/124            170/124            165/119

COMMENT: Solar activity on UT day 25-Jul was R1, with an isolated 
M1 solar flare from AR3751 (S08W81, beta). There are currently 
eleven numbered sunspot regions on the solar disk. The only region 
of note is AR3762 (S13W02, beta-gamma) which has been changing 
rapidly, with growth in complexity. All other sunspot regions 
are either stable or in decay. Solar activity is expected to 
be R0-R1 with a chance for R2 over 26-28 Jul. 

>From 25/0024 UT, a weak halo CME was observed. This event has
 been determined as likely farside, however dimming can be seen
from near AR3762 shortly before this CME in association with a C8 
flare. It is possible material from the dimming event associated with 
the C8 flare has been overshadowed by the farside halo; in which 
case, arrival from this material is estimated to be on 27-Jul, 
although this is low confidence. No other potentially Earth-directed 
CMEs were observed on 25-Jul. 

S0 solar radiation storm conditions were observed on 25-Jul. 
S0 solar radiation storm conditions are expected over 26-28 Jul. 

The solar wind environment was mildly disturbed on UT day 25-Jul due 
to a transient feature or possibly recent CME, however the source 
is not clear. The solar wind speed increased from near 300 to 470 km/s. 
The peak total interplanetary field strength (IMF, Bt) was 19 nT and 
the north-south IMF component range (Bz) was +13 to -11 nT. The 
solar wind is expected to be somewhat disturbed over 26-28 Jul,
 due to a weak glancing blow from a recent CME on 26-Jul, 
followed by the material from the dimming event on 27-Jul.
 A weak coronal hole feature is also developing in the centre disk 
that may increase the solar wind speed by 28-Jul.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 25 Jul: G0

Estimated Indices 25 Jul : A   K           
   Australian Region       5   12112222
      Cocos Island         5   12212212
      Darwin               6   22212222
      Townsville           6   22112222
      Learmonth            7   22212232
      Alice Springs        5   12112222
      Gingin               4   11111222
      Canberra             4   12011122
      Kennaook Cape Grim   3   11011122
      Hobart               3   11011122    

Estimated Antarctic Regional K Indices 25 Jul :
      Macquarie Island     0   00000011
      Casey                7   12201332
      Mawson              20   22101356

Observed Regional daily pc3 Indices 25 Jul : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            0   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin               0   (Quiet)
      Canberra             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 25 Jul : A 
           Fredericksburg         6
           Planetary              6                         

Observed AFr/Ap Indices 24 Jul :  A   K
           Fredericksburg         8
           Planetary              6   2221 2222     

2B. MAGNETIC FORECAST 
Date      Ap    Conditions
26 Jul    12    G0, chance G1
27 Jul    16    G0, chance G1
28 Jul    10    G0, very slight chance G1

COMMENT: G0 geomagnetic conditions were observed in the Australian 
region on UT day 25-Jul. Mostly G0 conditions were observed in 
Antarctica, with an isolated period of G1 in Mawson. Mostly G0 
geomagnetic conditions are expected over 26-28 Jul, however periods 
of G1 are possible on 26 and 27 Jul due to two possible weak 
CME glancing blows. Coronal hole high speed winds may also contribute 
to enhanced geomagnetic activity by 28-Jul.

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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
25 Jul      Normal         Normal         Normal         

PCA Event : No event.

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

COMMENT: HF radio communication conditions on UT day 25-Jul were 
mostly normal. HF radio communication conditions are expected 
to be normal to fair over 26-28 Jul, as several weak geomagnetic 
disturbances are expected over the period. Impacts will be strongest 
at high latitudes and during local night hours.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY

Date   T index
25 Jul   132

Observed Australian Regional MUFs
   Cocos Island Region:
      Enhanced by 40% during local day.
      Enhanced by 15% during local night.
   Niue Island Region:
      Near predicted monthly values.
   Northern Australian Region:
      Mostly near predicted monthly values.
      Depressed by 20% after local dawn.
   Southern Australian Region:
      Near predicted monthly values.
   Antarctic Region (Casey/Davis/Mawson):
      Enhanced by 25% over the UT day.

Monthly T index:
Month  T index
Jun      120
Jul      118
Aug      117

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
26 Jul   130    Near predicted monthly values
27 Jul   125    Near predicted monthly values
28 Jul   120    Near predicted monthly values

COMMENT: Maximum usable frequencies (MUFs) on UT day 25-Jul were 
near predicted values to 20% depressed in the Australia region. 
Spread F and sporadic E were observed in Hobart during local 
night hours. MUFs are expected to be near predicted values over 
26-28 Jul.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 24 Jul
       Daily Proton Fluence >1 MeV:   9.0E+06
       Daily Proton Fluence >10 MeV:  1.0E+05
       Daily Electron Fluence >2 MeV: 1.10E+06   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 1%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C1.3

DSCOVR Satellite Solar Wind Day Averaged Data for 24 Jul
Speed: 322 km/sec  Density:    1.3 p/cc  Temp:    50900 K  Bz:   3 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