[Ips-dsgr] ASWFC Daily Report - 17 March 23 issued 2333 UT on 17 Mar 2023 [SEC=OFFICIAL]
rwc
rwc at ips.gov.au
Sat Mar 18 10:33:35 EST 2023
SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/17 MARCH 2023
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 17 MARCH AND FORECAST FOR 18 MARCH - 20 MARCH
STATUS INDICATORS SOL:** YELLOW ** MAG:** RED ** ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 17 Mar: R1
Flares Max Fadeout Freq. Sectors
M1.0 1507UT Possible lower South American/Atlantic
Observed 10.7 cm flux/Equivalent Sunspot Number for 17 Mar: 134/88
1B. SOLAR FORECAST
18 Mar 19 Mar 20 Mar
Activity R0-R1 R0-R1 R0-R1
Fadeouts Possible Possible Possible
10.7cm/SSN 132/86 130/84 128/81
COMMENT: Solar activity on UT day 17-Mar was at the R1 level,
due to a brief M1.0 flare at 17/1507UT from minor solar region
AR3247(S23W71, alpha). South east solar limb activity was observed
near region AR3256(S24E80, beta) associated with a broad slow
rise and fall X-ray flux enhancement during 17/1200-1630UT. Solar
region AR3256 produced C class flare activity with the largest
events two C6.4 flares at 17/0626UT and 17/0652UT. Solar region
AR3256 currently appears as a large single spot but may have
trailers following this spot or another region is following.
Emission is also currently visible on the north east solar limb
at N25 possibly indicating the return of previous flare active
region AR3234, but at this stage it does not appear very large/bright.
There are currently 7 numbered sunspot regions on the visible
disk. Other solar regions are small and uninteresting. A large
48 degree long filament located in the solar south west quadrant,
centred at S30W25 erupted from 17/0700-1000UT and a subsequent
south west directed CME was observed in LASCO C2 imagery from
17/1058UT. Event modelling indicates a CME arrival middle of
the UT day on 19-Mar. Due to a lack of available images CME analysis
was restricted to C2 imagery only. The southern solar latitude
of this filament may reduce induced activity at the Earth, with
model output showing the bulk of the CME passing under the Earth.
A small 10 degree long solar filament erupted from 17/1718UT
but did not appear to have an associated CME. The start of a
bright south west CME was observed from 17/1950UT in LASCO C2
imagery and appears to be associated with south west limb activity
at solar latitude S25 and due the west limb location is not considered
as Earth directed. Due to activity near/from solar region AR3256
and the possible return of AR3234, solar activity may generally
increase in coming days and R0-R1 activity is expected. The solar
wind speed on UT day 17-Mar ranged from 450 to 414 km/s with
a slight declining trend, and is currently near 417 km/s. The
peak total interplanetary field strength (IMF, Bt) was 6 nT and
the north-south IMF component (Bz) range was +5 to -5 nT. Solar
wind speed is expected to decline to background levels over 18-Mar,
then solar wind parameters are expected to become enhanced during
19-Mar due to the filament eruption. A large coronal hole is
visible in the far south east solar quadrant.
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2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 17 Mar: G0
Estimated Indices 17 Mar : A K
Australian Region 4 12222002
Cocos Island 2 11211001
Darwin 5 22222002
Townsville 5 12222012
Learmonth 5 22222002
Alice Springs 4 12222002
Gingin 4 11222002
Canberra 4 12122002
Hobart 5 12223001
Estimated Antarctic Regional K Indices 17 Mar :
Macquarie Island 7 02234001
Casey 12 34432012
Mawson 13 23332015
Observed Regional daily pc3 Indices 17 Mar :
Darwin 0 (Quiet)
Townsville 0 (Quiet)
Learmonth 0 (Quiet)
Alice Springs 0 (Quiet)
Gingin 0 (Quiet)
Canberra 0 (Quiet)
Hobart 2 (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 17 Mar : A
Fredericksburg 7
Planetary 7
Observed AFr/Ap Indices 16 Mar : A K
Fredericksburg 6
Planetary 7 4301 1211
2B. MAGNETIC FORECAST
Date Ap Conditions
18 Mar 6 G0
19 Mar 35 Initially G0, then G1-G2 conditions
20 Mar 18 Initially G1, then declining to G0
COMMENT: G0 geomagnetic conditions were observed in the Australian
region and Antarctic region on UT day 17-Mar. G0 conditions generally
observed in the Antarctic region, with an isolated period of
G1 observed at Mawson. G0 conditions are expected for 18-Mar.
ASWAS G1, with the chance of G2 conditions are expected from
second half of 19-Mar due to a recent solar filament eruption/CME.
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3A. GLOBAL HF PROPAGATION SUMMARY
Latitude Band
Date Low Middle High
17 Mar Normal Normal Normal
PCA Event : No event.
3B. GLOBAL HF PROPAGATION FORECAST
Latitude Band
Date Low Middle High
18 Mar Normal Normal Normal
19 Mar Normal Normal-poor Normal-poor
20 Mar Normal Poor-normal Poor-fair
COMMENT: HF propagation conditions on 17-Mar were normal. Normal
HF conditions are expected for 18-Mar. HF propagation conditions
on 19-Mar are initially expected to be normal, then becoming
degraded later in the UT day at middle to high latitudes due
to the anticipated arrival of a recent CME associated with a
solar filament eruption. Isolated minor fadeouts possible.
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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date T index
17 Mar 137
Observed Australian Regional MUFs
Cocos Island Region:
Near predicted monthly values during local day.
Enhanced by 55% during local night.
Enhanced by 55% after local dawn.
Niue Island Region:
Enhanced by 25% during local day.
Enhanced by 70% during local night.
Northern Australian Region:
Enhanced by 15-30%.
Southern Australian Region:
Enhanced by 25-35%.
Antarctic Region (Casey/Scott Base/Davis/Mawson):
Near predicted monthly values over the UT day.
Monthly T index:
Month T index
Feb 117
Mar 80
Apr 80
4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date T index MUFs
18 Mar 140 15 to 30% above predicted monthly values
19 Mar 140 15 to 30% above predicted monthly values
20 Mar 80 Depressed 20%/15% above predicted monthly values
COMMENT: Maximum usable frequencies (MUFs) on UT day 17-Mar in
the Australian region were enhanced by 15-70%. Scintillation
was observed at Niue from 17/1042-1059UT. MUFs are expected to
be enhanced by 15-30% over 18-Mar. Southern Australian region
MUFs are expected to become depressed on 20-Mar if geomagnetic
activity induced from a recent erupting solar filament eventuates.
Northern Australian region MUFs are expected to remain enhanced.
Isolated minor fadeouts possible.
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5. SPACE ENVIRONMENT SUMMARY
GOES satellite data for 16 Mar
Daily Proton Fluence >1 MeV: 5.3E+06
Daily Proton Fluence >10 MeV: 5.4E+04
Daily Electron Fluence >2 MeV: 1.90E+06 (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 1%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
X-ray background: B6.1
DSCOVR Satellite Solar Wind Day Averaged Data for 16 Mar
Speed: 509 km/sec Density: 8.2 p/cc Temp: 264000 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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