[Ips-dsgr] ASWFC Daily Report - 08 December 24 issued 2330 UT on 08 Dec 2024 [SEC=OFFICIAL]

Australian Space Weather Forecasting Centre aswfc at bom.gov.au
Mon Dec 9 10:30:47 AEDT 2024


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/08 DECEMBER 2024
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 08 DECEMBER AND FORECAST FOR 09 DECEMBER - 11 DECEMBER
STATUS INDICATORS SOL:** YELLOW **   MAG:GREEN     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 08 Dec:  R3

Flares    Max     Fadeout    Freq.  Sectors
  M3.2 07/2215UT  possible   lower  East Pacific/
                                    North American
  X2.2    0906UT  probable   all    Mid East/Indian
  M1.5    1611UT  possible   lower  South American/
                                    Atlantic

Observed 10.7 cm flux/Equivalent Sunspot Number for 08 Dec: 178/131


1B. SOLAR FORECAST
             09 Dec             10 Dec             11 Dec
Activity     R0-R1 chance R2-R3 R0-R1 chance R2-R3 R0-R1 chance R2-R3
Fadeouts     Possible           Possible           Possible
10.7cm/SSN   180/133            175/129            175/129

COMMENT: Solar activity on UT day 08-Dec was at the R3 level 
due to an X2.2 flare at 08/0906UT and an M1.5 flare at 08/1611UT. 
There are currently six numbered sunspot regions visible on the 
solar disk and one unnumbered region. AR3912 (S06W50, beta-gamma) 
was responsible for both noteworthy flares in the UT day and 
has shown spot development. This region is expected to remain 
on the solar disk until 11-Dec. AR3917 (S09E13, beta-delta) remains 
magnetically complex, but has not produced any notable flares 
recently. An unnumbered region has rotated on to the disk at 
around N25E65 likely with beta magnetic characteristics. All 
other sunspot regions are either stable or in decay. Solar activity 
is expected to be at R0-R1 levels, with a chance of isolated 
R2-R3 flares over 09-11 Dec. S0 solar radiation storm conditions 
were observed on 08-Dec. S0 conditions are expected on 09-11 
Dec, with a chance of S1 conditions due to possible further X-class 
flares from AR3912. A CME associated with the X2.2 flare at 08/0906UT 
is visible in SOHO and STEREO-A imagery from 08/0924UT. Modelling 
suggests this CME will mostly pass ahead of Earth, but there 
is a chance of a glancing impact late on 11-Dec (11/1700 +/- 
12 hours). The solar wind speed declined for most of the UT day, 
ranging between 400 km/s and 325 km/s. An increase was then observed 
from around 09/1730UT. The wind speed is currently around 450 
km/s but peaked at 492 km/s. The peak total interplanetary field 
strength (IMF, Bt) was 11 nT and the north-south IMF component 
(Bz) range was +6 to -9 nT. A jump in Bt was observed from around 
09/1730UT concurrent with the increase in solar wind speed. The 
increase in solar wind speed and IMF Bt was concurrent with a 
drop in solar wind density, indicating the Earth has entered 
a high speed wind stream from a pair of coronal holes which have 
recently rotated into geoeffective positions. The solar wind 
speed is expected to remain slightly elevated over 09-11 Dec 
due to coronal hole high speed wind stream effects and the chance 
of a glancing impact on 11-Dec from a CME first observed on 08-Dec.

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2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 08 Dec: G0

Estimated Indices 08 Dec : A   K           
   Australian Region       5   12122221
      Cocos Island         3   22012110
      Darwin               5   12122211
      Townsville           7   23112231
      Learmonth            6   22122222
      Alice Springs        4   02022221
      Gingin               6   21132122
      Canberra             5   12112230
      Kennaook Cape Grim   5   22112221
      Hobart               5   12112221    

Estimated Antarctic Regional K Indices 08 Dec :
      Macquarie Island     7   11224220
      Casey               14   44332222
      Mawson              13   34233232

Observed Regional daily pc3 Indices 08 Dec : 
      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 08 Dec : A 
           Fredericksburg         7
           Planetary              7                         

Observed AFr/Ap Indices 07 Dec :  A   K
           Fredericksburg         5
           Planetary              4   1111 1111     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
09 Dec    12    G0, chance of G1
10 Dec     8    G0
11 Dec    12    G0, chance of G1

COMMENT: G0 geomagnetic conditions were observed in the Australian 
and Antarctic regions on UT day 08-Dec. G0 geomagnetic conditions, 
with a chance of G1 are expected on 09-Dec due to coronal hole 
high speed wind stream effects. G0 conditions are expected on 
10-Dec. G0 conditions, with a chance of G1 are expected on 11-Dec 
due to the chance of a glancing impact from a CME first observed 
on 08-Dec.

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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
08 Dec      Normal-fair    Normal-fair    Fair-poor      

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
09 Dec      Normal         Normal         Normal-fair
10 Dec      Normal         Normal         Normal-fair
11 Dec      Normal         Normal         Normal-fair

COMMENT: HF radio propagation conditions were mostly normal on 
UT day 08-Dec, with fair-poor conditions over the Americas for 
the first and last thirds of the UT day. Fair-poor conditions 
were observed at high latitudes in the last third of the UT day. 
HF radio propagation conditions are expected to be mostly fair-normal 
over 09-11 Dec, with the best conditions in the middle of the 
UT day. Shortwave fadeouts are possible.

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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
08 Dec   133

Observed Australian Regional MUFs
   Cocos Island Region:
      Mostly near predicted monthly values.
   Niue Island Region:
      Near predicted monthly values.
   Northern Australian Region:
      Near predicted monthly values.
   Southern Australian Region:
      Mostly near predicted monthly values.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

Monthly T index:
Month  T index
Nov      127
Dec      117
Jan      114

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
09 Dec   140    Near to 15% above predicted monthly values
10 Dec   140    Near to 15% above predicted monthly values
11 Dec   140    Near to 15% above predicted monthly values

COMMENT: ASWFC SWF HF Communications Warning 142 was issued on 
8 December and is current for 8-10 Dec. Maximum usable frequencies 
(MUFs) in the Australian region on UT day 08-Dec were near predicted 
monthly values, with some isolated periods of sporadic E impacting 
local HF propagation conditions at Darwin, Townsville, Hobart 
and Norfolk Island. MUFs are expected to be near predicted monthly 
values to 15% enhanced over 09-11 Dec, with further isolated 
periods of sporadic E possible. Shortwave fadeouts are possible.

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5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 07 Dec
       Daily Proton Fluence >1 MeV:   1.1E+05
       Daily Proton Fluence >10 MeV:  1.4E+04
       Daily Electron Fluence >2 MeV: 1.70E+06   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 1%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C1.6

DSCOVR Satellite Solar Wind Day Averaged Data for 07 Dec
Speed: 366 km/sec  Density:    9.5 p/cc  Temp:    44100 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



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