[Ips-dsgr] ASWFC Daily Report - 12 September 23 issued 2330 UT on 12 Sep 2023 [SEC=OFFICIAL]
Regional Warning Centre
rwc at ips.gov.au
Wed Sep 13 09:30:08 EST 2023
SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/12 SEPTEMBER 2023
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 12 SEPTEMBER AND FORECAST FOR 13 SEPTEMBER - 15 SEPTEMBER
STATUS INDICATORS SOL:** YELLOW ** MAG:GREEN ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 12 Sep: R1
Flares Max Fadeout Freq. Sectors
M1.9 0426UT possible lower E. Asia/Aust.
M2.5 0707UT possible lower Mid East/Indian
Observed 10.7 cm flux/Equivalent Sunspot Number for 12 Sep: 154/109
1B. SOLAR FORECAST
13 Sep 14 Sep 15 Sep
Activity R0-R1 R0-R1 R0-R1
Fadeouts Possible Possible Possible
10.7cm/SSN 160/114 155/109 152/107
COMMENT: Solar activity on UT day 12-Sep was at the R1 level,
with two R1 class flares observed. Solar region AR3425(N25W10,
beta) produced the M1.9 flare and solar region AR3423(N17W47,
beta) produced the M2.5 flare. Solar region AR3425 is now in
decay and intermediate spots in AR3423 are in decay, though the
region is mostly stable. Recently flaring regions AR3429(N11E34,
beta) and AR3431(S08E36, beta) are also in decay. There are currently
8 solar regions visible on the solar disk. Other regions are
small and are either stable or in decay. Solar activity is expected
to be at the R0-R1 level over 13-15 Sep. The solar wind parameters
on UT day 12-Sep exhibited what is currently considered a glancing
blow from a slow CME transient, though the ACE EPAM CME arrival
precursor channel did not show an increasing trend prior to the
CMEs arrival. There are two weak discontinuities in the solar
wind speed parameter at 12/1020UT and 12/1125UT, with the second
discontinuity evident across other solar wind parameters. Though
the CME speed was slow with peak speed of approximately 420km/sec,
the embedded IMF was orientated strongly southward with IMF Bz
falling to -19nT at 12/1430UT. then slowly recovering. Overall
on 12-Sep, the solar wind speed ranging from 330 to 429 km/s
and is currently near 390 km/s. The peak total interplanetary
field strength (IMF, Bt) was 20 nT and the north-south IMF component
(Bz) range was +10 to -19 nT. Two small coronal holes just west
of the solar central meridian may mildly increase the solar wind
speed in two days time.
-----------------------------------------------------------
2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 12 Sep: G1
Estimated Indices 12 Sep : A K
Australian Region 18 12134543
Cocos Island 12 11134432
Darwin 15 12134443
Townsville 22 22145543
Learmonth 22 22145543
Alice Springs 20 12135543
Gingin 17 11134543
Canberra 14 11034532
Hobart 17 11034543
Estimated Antarctic Regional K Indices 12 Sep :
Macquarie Island 33 00036742
Casey 15 23324432
Mawson 44 23224844
Observed Regional daily pc3 Indices 12 Sep :
Darwin 0 (Quiet)
Townsville 0 (Quiet)
Learmonth 0 (Quiet)
Alice Springs 0 (Quiet)
Gingin 43 (Unsettled)
Canberra 39 (Quiet to unsettled)
Hobart 19 (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 12 Sep : A
Fredericksburg 20
Planetary 32
Observed AFr/Ap Indices 11 Sep : A K
Fredericksburg 8
Planetary 7 2222 2222
2B. MAGNETIC FORECAST
Date Ap Conditions
13 Sep 13 G0
14 Sep 10 G0
15 Sep 7 G0
COMMENT: G1 geomagnetic conditions were observed in the Australian
region on 12-Sep. Periods of G2-G3 were observed at Macquarie
Island and an isolated period of G4 was observed at Mawson. The
unexpected brief increase in geomagnetic activity is considered
to be from a glancing blow from a slow moving CME(s). G0 geomagnetic
conditions are expected over 13-15 Sep.
-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
Latitude Band
Date Low Middle High
12 Sep Normal Normal-fair Normal-poor
PCA Event : No event.
3B. GLOBAL HF PROPAGATION FORECAST
Latitude Band
Date Low Middle High
13 Sep Normal Fair-normal Fair-normal
14 Sep Normal Normal Normal
15 Sep Normal Normal Normal
COMMENT: HF radio propagation conditions on UT day 12-Sep were
degraded at middle to high latitudes. Degraded HF conditions
may be experienced early in the UT day on 13-Sep, then improving.
Mostly normal HF conditions are expected over 14-15 Sep. Isolated
minor shortwave fadeouts are possible.
-----------------------------------------------------------
4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date T index
12 Sep 116
Observed Australian Regional MUFs
Cocos Island Region:
Near predicted monthly values during local day.
Enhanced by 45% during local night.
Niue Island Region:
Mostly near predicted monthly values.
Enhanced by 20% after local dawn.
Northern Australian Region:
Near predicted monthly values during local day.
Enhanced by 20% during local night.
Southern Australian Region:
Mostly near predicted monthly values.
Depressed 15% after local dawn.
Antarctic Region (Casey/Davis/Mawson):
Enhanced by 15% over the UT day.
Monthly T index:
Month T index
Aug 115
Sep 96
Oct 93
4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date T index MUFs
13 Sep 80 Depressed 15 to 20%/near predicted monthly values
14 Sep 110 Near predicted monthly values
15 Sep 110 Near predicted monthly values
COMMENT: ASWFC SWF HF Communications Warning 89 was issued on
11 September and is current for 11-13 Sep. Maximum usable frequencies
(MUFs) on UT day 12-Sep were generally near predicted monthly
values to 20% enhanced in the Australian region. HF conditions
became mildly degraded overnight in the southern Australian region
with spread F was observed at Hobart during local night hours.
Depressions of 15% have been observed after local dawn this morning
for the southern Australian region. Depressed conditions may
persist into early in the UT day on 13-Sep, then MUFs are expected
to recover as brief overnight geomagnetic activity has abated.
Very minor fadeouts may have been experienced at 12/0426UT and
12/0707UT in association with R1 flare activity. MUFs are generally
expected to be near predicted monthly values over 13-15 Sep.
Isolated minor shortwave fadeouts are possible.
-----------------------------------------------------------
5. SPACE ENVIRONMENT SUMMARY
GOES satellite data for 11 Sep
Daily Proton Fluence >1 MeV: 2.4E+05
Daily Proton Fluence >10 MeV: 1.8E+04
Daily Electron Fluence >2 MeV: 2.70E+06 (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 1%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
X-ray background: C1.5
DSCOVR Satellite Solar Wind Day Averaged Data for 11 Sep
Speed: 390 km/sec Density: 5.6 p/cc Temp: 80400 K Bz: 2 nT
(Courtesy Space Weather Prediction Center, Boulder USA)
-----------------------------------------------------------
Australian Space Weather Forecasting Centre
Bureau of Meteorology
ASWFC at bom.gov.au
www.bom.gov.au | www.sws.bom.gov.au
More information about the ips-dsgr
mailing list