[Ips-dsgr] ASWFC Daily Report - 14 April 25 issued 2331 UT on 14 Apr 2025 [SEC=OFFICIAL]

Australian Space Weather Forecasting Centre aswfc at bom.gov.au
Tue Apr 15 09:31:24 AEST 2025


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/14 APRIL 2025
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 14 APRIL AND FORECAST FOR 15 APRIL - 17 APRIL
STATUS INDICATORS SOL:** YELLOW **   MAG:** YELLOW **     ION: ** YELLOW **
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 14 Apr:  R1

Flares    Max     Fadeout    Freq.  Sectors 
  M1.4    0605UT  possible   lower  Mid East/Indian
  M4.2    0646UT  possible   lower  Mid East/Indian
  

Observed 10.7 cm flux/Equivalent Sunspot Number for 14 Apr: 152/107


1B. SOLAR FORECAST
             15 Apr             16 Apr             17 Apr
Activity     R1,chance R2       R0-R1              R0-R1
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   165/119            165/119            160/114

COMMENT: Solar activity on UT day 14-Apr was at the R1 level. 
Solar region AR4055 (N07W89, beta-gamma-delta) produced both 
the M4.2 and M1.4 flare events. This region is rotating over 
the northwest solar limb and also produced several C class flares. 
The other region of interest, solar region AR4060 (N09E09, beta-gamma) 
has been mostly flare quiet, with some spot redistribution and 
is possibly starting to decay. A new small to medium sized solar 
region is rotating onto the solar disk at S04E80. There are currently 
four numbered sunspot regions and one unnumbered region on visible 
on the solar disk. All other sunspot groups were either stable 
or in decay. Solar activity is expected to be at the R1 level, 
with a chance of R2 on 15-Apr, with a behind the limb flare possible 
from AR4055. R0-R1 level flare activity is expected over 16-17 
Apr. S0 solar radiation storm conditions were observed on UT 
day 14-Apr. S0 solar radiation storm conditions are expected 
over 15-17 Apr. No Earth directed CMEs have been observed on 
14-Apr. A narrow southward CME was observed from 14/1500UT which 
could not be correlated to on disk activity. CMEs from two recent 
filament eruptions on late 12-Apr and on 13-Apr have been modelled 
to be Earth directed and are expected to arrive late in the UT 
day on 15-Apr and first half of the UT day on 16-Apr. The second 
arrival is expected to be weaker. The solar wind speed on UT 
day 14-Apr slowly declined. The wind speed mostly ranged between 
471 km/s and 389 km/s. The current wind speed is around 390 km/s. 
The peak total interplanetary field strength (IMF, Bt) was 8 
nT and the north-south IMF component range (Bz) was +5 to -7 
nT. A moderate to strong solar wind shock is expected late in 
the UT day on 15-Apr due to an anticipated impact from a CME 
first observed on 13-Apr. A weaker shock arrival is possible 
during the first half of the UT day on 16-Apr. The ACE EPAM low 
energy ion CME precursor channel is currently flat, possibly 
indicating a later than modelled arrival.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 14 Apr: G0

Estimated Indices 14 Apr : A   K           
   Australian Region       9   23213322
      Cocos Island         7   23212222
      Darwin               8   23213222
      Townsville          12   34213223
      Learmonth           12   33213333
      Alice Springs        9   23213322
      Gingin              12   33213333
      Canberra             9   23312322
      Kennaook Cape Grim   -   --------
      Hobart              11   23323322    

Estimated Antarctic Regional K Indices 14 Apr :
      Macquarie Island    19   35434321
      Casey               20   45422333
      Mawson              44   36432656

Observed Regional daily pc3 Indices 14 Apr : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            0   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin               2   (Quiet)
      Canberra             6   (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 14 Apr : A 
           Fredericksburg        13
           Planetary             14                         

Observed AFr/Ap Indices 13 Apr :  A   K
           Fredericksburg         0
           Planetary              0   4432 3232     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
15 Apr    20    Initially G0, then G1-G2 late in UT day.
16 Apr    30    G1-G2
17 Apr    16    G1 periods possible early in UT day then G0

COMMENT: ASWFC Geomagnetic Warning 28 was issued on 14 April 
and is current for 15-16 Apr. G0 geomagnetic conditions were 
observed in the Australian region on UT day 14-Apr. G1-G2 conditions 
were observed in the Antarctic region. G1-G2 conditions are expected 
from late in the UT day on 15-Apr and on 16-Apr due to an anticipated 
impact from a partial halo CME first observed on 13-Apr.

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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
14 Apr      Normal         Fair-normal    Fair           

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
15 Apr      Normal         Normal-fair    Fair
16 Apr      Normal         Fair           Fair-poor
17 Apr      Normal         Normal-fair    Fair

COMMENT: HF radio propagation conditions on UT day 14-Apr were 
fair to normal, with fair conditions at middle to high latitudes. 
Degraded HF conditions for middle to high latitudes are expected 
from late on 15-Apr and over 16-Apr due to anticipated geomagnetic 
activity from expected CME arrivals.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
14 Apr   116

Observed Australian Regional MUFs
   Cocos Island Region:
      Enhanced by 25% during local day.
      Enhanced by 45% during local night.
   Niue Island Region:
      Enhanced by 30% during local day.
      Near predicted monthly values during local night.
      Enhanced by 20% after local dawn.
   Northern Australian Region:
      Near predicted monthly values.
   Southern Australian Region:
      Near predicted monthly values during local day.
      Southeast depressed by 25% during local night.
   Antarctic Region (Casey/Davis/Mawson):
      Depressed by 20% over the UT day.

Monthly T index:
Month  T index
Mar      126
Apr      115
May      113

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
15 Apr   120    Near predicted monthly values/depressed 5 to 
                15%
16 Apr    75    Depressed 15 to 20%/near predicted monthly values
17 Apr    95    Depressed 10 to 15%/near predicted monthly values

COMMENT: ASWFC SWF HF Communications Warning 37 was issued on 
14 April and is current for 14-15 Apr. Maximum usable frequencies 
(MUFs) in the Australian region on UT day 14-Apr were generally 
near predicted values with depressions of 25% observed during 
local night hours for the southeast Australian region. Spread-F 
was observed during local night hours at Hobart. MUFs are expected 
to be initially near predicted monthly values on 15-Apr, with 
depressed conditions possible late in the UT day for the southern 
Australian region. Southern Australian region MUFs are expected 
to be depressed 15-20% on 16-Apr if CME induced geomagnetic storm 
activity eventuates late in the UT day on 15-Apr.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 13 Apr
       Daily Proton Fluence >1 MeV:   4.1E+05
       Daily Proton Fluence >10 MeV:  1.5E+04
       Daily Electron Fluence >2 MeV: 3.40E+07   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 5%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C4.1

DSCOVR Satellite Solar Wind Day Averaged Data for 13 Apr
Speed: 489 km/sec  Density:    1.1 p/cc  Temp:   102000 K  Bz:  -2 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



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