[Ips-dsgr] ASWFC Daily Report - 23 November 23 issued 2330 UT on 23 Nov 2023 [SEC=OFFICIAL]
Regional Warning Centre
rwc at ips.gov.au
Fri Nov 24 10:30:10 EST 2023
SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/23 NOVEMBER 2023
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 23 NOVEMBER AND FORECAST FOR 24 NOVEMBER - 26 NOVEMBER
STATUS INDICATORS SOL:** YELLOW ** MAG:** YELLOW ** ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
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1A. SOLAR SUMMARY
Activity 23 Nov: R1
Flares Max Fadeout Freq. Sectors
M1.4 0339UT possible lower E. Asia/Aust.
M1.1 1437UT possible lower South American/
Atlantic
Observed 10.7 cm flux/Equivalent Sunspot Number for 23 Nov: 194/146
1B. SOLAR FORECAST
24 Nov 25 Nov 26 Nov
Activity R0-R1 R0-R1 R0-R1
Fadeouts Possible Possible Possible
10.7cm/SSN 195/147 195/147 195/147
COMMENT: Solar activity on UT day 23-Nov was R1, with two low-level
M-class solar flares. An M1 flare at 23/0340 UT was from a region
beyond the eastern limb not yet in view; and the other M1 solar
flare was from region AR3490 (N25E18, beta). There are currently
eleven sunspot regions on the solar disk, however many of these
belong to the group in the solar northeast. For the most part,
all sunspots in the northeast group have remained stable over
the past 24 hours. AR3499 (S18E05, beta) has had minor growth
and AR35000 (S17E61, gamma) is currently the most complex sunspot
on the solar disk. Solar activity is expected to be R0-R1 over
24-26 Nov.
A CME that was mentioned in yesterday's report that
was first seen from 22/2148 UT has been reanalysed. This CME
may potentially have come from the frontside of the Sun rather
than the back, as there was some coronal dimming near AR3489
(S16W05, alpha) and a C4 solar flare at the time. It is also
possible this is two separate CMEs occurring concurrently. Confidence
is low that this CME is associated with this front side event,
as this kind of CME would be expected to be correlated with more
obvious activity. Should this CME be front side, it may impact
earth by late 25-Nov. Effects from this event may also be exacerbated
by a coronal hole.
Several other CMEs were observed on 23-Nov.
Many were from large prominence eruptions near or over the eastern
solar limb, and are not considered to be geoeffective.
The solar
wind environment began returning to background levels on 23-Nov
as Earth exited a coronal hole wind stream. The peak total interplanetary
field strength (MF, Bt) was 5 nT and the north-south IMF component
(Bz) range was +3 to -4 nT. The solar wind speed was on a general
declining trend and ranged from 547 to 375 km/s. The solar wind
is expected to be near background levels over 24-25 Nov. The
solar wind may become enhanced by the end of 26-Nov due to a
small coronal hole that is currently crossing the central meridian.
If the above mentioned CME is indeed a frontside CME, then the
solar wind parameters will also increase by late 25-Nov.
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2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 23 Nov: G0
Estimated Indices 23 Nov : A K
Australian Region 2 11211001
Cocos Island 1 11100000
Darwin 2 11211001
Townsville 3 21211011
Learmonth 3 21211001
Alice Springs 2 11211001
Gingin 3 21211001
Canberra 2 11211001
Hobart 4 12312001
Estimated Antarctic Regional K Indices 23 Nov :
Macquarie Island 5 12313001
Casey 22 46522112
Mawson 13 34423211
Observed Regional daily pc3 Indices 23 Nov :
Darwin 0 (Quiet)
Townsville 0 (Quiet)
Learmonth 0 (Quiet)
Alice Springs 0 (Quiet)
Gingin 0 (Quiet)
Canberra 0 (Quiet)
Hobart 4 (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 23 Nov : A
Fredericksburg 9
Planetary 10
Observed AFr/Ap Indices 22 Nov : A K
Fredericksburg 17
Planetary 24 3554 3442
2B. MAGNETIC FORECAST
Date Ap Conditions
24 Nov 6 G0
25 Nov 6 G0
26 Nov 20 G1, chance G2
COMMENT: G0 geomagnetic conditions were observed in the Australian
region on UT day 23-Nov. Mostly G0 geomagnetic conditions were
observed in the Antarctic region with some G1-G2 conditions at
Casey. G0 geomagnetic conditions are expected over 24-25 Nov.
There is a possibility of a CME impact late on 25-Nov, combined
with a coronal hole wind stream on 26-Nov. If the CME does make
impact, G1-G2 geomagnetic conditions are expected on early 26-Nov.
If the CME does not make impact then isolated periods of G1 will
be possible throughout the day of 26-Nov.
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3A. GLOBAL HF PROPAGATION SUMMARY
Latitude Band
Date Low Middle High
23 Nov Normal-fair Fair Fair
PCA Event : No event.
3B. GLOBAL HF PROPAGATION FORECAST
Latitude Band
Date Low Middle High
24 Nov Normal Normal Normal-fair
25 Nov Normal Normal Normal-fair
26 Nov Normal-fair Fair Fair
COMMENT: HF radio communication conditions on UT day 23-Nov were
depressed and degraded in the southern hemisphere for the first
half of the day. HF radio communication conditions are expected
to be mostly normal over 24-25 Nov. HF radio communication conditions
may become degraded on 26-Nov due to geomagnetic activity. Isolated
shortwave fadeouts are possible.
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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date T index
23 Nov 100
Observed Australian Regional MUFs
Cocos Island Region:
Near predicted monthly values.
Niue Island Region:
Enhanced by 20% during local day.
Enhanced by 25% during local night.
Northern Australian Region:
Near predicted monthly values.
Southern Australian Region:
Depressed by 20% during local day.
Near predicted monthly values during local night.
Antarctic Region (Casey/Davis/Mawson):
Near predicted monthly values over the UT day.
Monthly T index:
Month T index
Oct 130
Nov 100
Dec 98
4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date T index MUFs
24 Nov 100 Near predicted monthly values
25 Nov 110 Near predicted monthly values
26 Nov 90 Near predicted monthly values to 15-20% depressed
COMMENT: ASWFC SWF HF Communications Warning 117 was issued on
22 November and is current for 23-24 Nov. Maximum usable frequencies
(MUFs) were near predicted monthly values to 20% depressed in
the Australian region on 23-Nov. Sporadic-E and spread-F was
observed at Hobart during local day and night hours. MUFs are
expected to be mostly near predicted monthly values over 24-25
Nov. MUFs may become depressed by 15-20% by 26-Nov due to anticipated
geomagnetic activity.
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5. SPACE ENVIRONMENT SUMMARY
GOES satellite data for 22 Nov
Daily Proton Fluence >1 MeV: 1.7E+05
Daily Proton Fluence >10 MeV: 1.8E+04
Daily Electron Fluence >2 MeV: 3.40E+06 (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 1%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
X-ray background: C2.7
DSCOVR Satellite Solar Wind Day Averaged Data for 22 Nov
Speed: 525 km/sec Density: 3.9 p/cc Temp: 248000 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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