[Ips-dsgr] ASWFC Daily Report - 11 May 24 issued 2340 UT on 11 May 2024 [SEC=OFFICIAL]
rwc
rwc at ips.gov.au
Sun May 12 09:40:44 EST 2024
SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/11 MAY 2024
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 11 MAY AND FORECAST FOR 12 MAY - 14 MAY
STATUS INDICATORS SOL:** RED ** MAG:** RED ** ION: ** RED **
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 11 May: R3
Flares Max Fadeout Freq. Sectors
M1.0 0105UT possible lower West Pacific
X5.8 0123UT probable all West Pacific
M1.2 0743UT possible lower Mid East/Indian
M1.7 0915UT possible lower Mid East/Indian
M3.1 1018UT possible lower European
X1.5 1144UT probable all European
M1.2 2041UT possible lower East Pacific/
North American
Observed 10.7 cm flux/Equivalent Sunspot Number for 11 May: 214/165
1B. SOLAR FORECAST
12 May 13 May 14 May
Activity R2-R3 R2-R3 R2-R3
Fadeouts Probable Probable Probable
10.7cm/SSN 220/170 220/170 215/165
COMMENT: Solar activity on UT day 11-May was at the R3 level
due an X5.8 flare from AR3664(S18W58, beta-gamma-delta). This
region also produced the X1.5 and M8.8 flares. Several lower
class R1 flares were also observed. This large and complex region
has shown some growth and redistribution in its intermediate
spots and some decay in its trailer spots. The regions solar
longitude is now quite west, with subsequent CME events likely
to be more component arrivals or increasingly Earth misses. Very
small regions AR3670(N19E08, beta) and AR3671(N24E05, beta) are
showing growth. New unnumbered very small spots have appeared
at S25E25. There are currently seven numbered regions and one
unnumbered region on the solar disk. All other sunspot regions
are either stable or in decay. Solar activity is expected to
be at R2-R3 levels over 12-14 May. The GOES solar proton flux
reached S2 at the 10MeV energy level with a peak flux of 116PFU
at 11/0910UT and is currently at S1. A 100MeV energy solar proton
event was also observed with a peak flux of 7.8PFU at 11/0720UT.
The X5.8 flare was associated with a CME with a component impact
expected to arrive 13/1300UT. The M8.8 flare was associated with
a narrow westward CME and is modelled as an Earth miss. The X1.5
flare was not associated with a CME. Following the strong shock
observed in the solar wind at 10/1637UT, the solar wind environment
on 11-May was extremely enhanced. The solar ranged from 592 to
993 km/s and is currently near 850 km/s. The peak total interplanetary
field strength (IMF, Bt) was 56 nT and the north-south IMF component
(Bz) range was +22 to -50 nT, with Bz strongly orientated southwards
during the interval 11/0000-1430UT. The solar winds IMF Bt has
now greatly reduced, however the solar wind speed is still fast
and is currently at 850km/sec. A partial shock signature is evident
in the solar wind at 11/1756UT. Further CMEs are arrivals are
expected over 12-May and 13-May which are expected to induce
less severe activity. These CMEs are associated with an X1 flare
at 09/144UT, an X3.9 at 10/0654UT and an X5.8 at 11/0123UT. The
last event has been modelled more as a component arrival due
to AR3664 increasingly westward solar longitude at the time of
the event. Two small isolated coronal holes are visible on the
solar disk at N25W35 and S35W35.
-----------------------------------------------------------
2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 11 May: G4
Estimated Indices 11 May : A K
Australian Region 127 76788655
Cocos Island 64 55667554
Darwin 76 65677545
Townsville 110 76787555
Learmonth 131 76788665
Alice Springs 98 76777555
Gingin 123 76688665
Canberra 129 66888654
Kennaook Cape Grim 207 76999755
Hobart 227 87999755
Estimated Antarctic Regional K Indices 11 May :
Macquarie Island 211 76999765
Casey 61 65666545
Mawson 191 76765899
Observed Regional daily pc3 Indices 11 May :
Darwin 92 (Minor storm)
Townsville 160 (Severe storm)
Learmonth NA
Alice Springs 180 (Severe storm)
Gingin NA
Canberra NA
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 11 May : A
Fredericksburg 268
Planetary 317
Observed AFr/Ap Indices 10 May : A K
Fredericksburg 80
Planetary 157 3322 3999
2B. MAGNETIC FORECAST
Date Ap Conditions
12 May 75 G3
13 May 45 G1-G2
14 May 18 G0
COMMENT: ASWFC Geomagnetic Warning 24 was issued on 11 May and
is current for 11-12 May. G4 geomagnetic conditions were observed
in the Australian region on UT day 11-May, with G5 geomagnetic
conditions observed in the Antarctic region. The geomagnetic
storm activity was induced by several CMEs. Further CME arrivals
are anticipated on 12 and 13-May, which are expected to induce
G3 conditions. Geomagnetic activity is then expected to decline
by 14-May.
-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
Latitude Band
Date Low Middle High
11 May Fair Poor-fair Poor(PCA)
PCA Event : 10MeV Proton/PCA Event Began at 1350UT 10/05, Ended at 0050UT 11/05
and, 10MeV Proton/PCA Event Began 11 05 2024 0210UT and is in progress
and, 100MeV Proton/PCA Event Began 11 05 2024 0155UT and is in progress
3B. GLOBAL HF PROPAGATION FORECAST
Latitude Band
Date Low Middle High
12 May Fair-normal Poor-fair Poor(PCA)
13 May Fair-normal Poor-fair Poor
14 May Normal Normal-fair Fair
COMMENT: HF radio communication conditions on UT day 11-May were
strongly degraded due to severe geomagnetic storm activity. Degraded
HF conditions are again expected for middle to high latitudes
for 12-May. Strong equatorial scintillation was observed in the
Australian region. High latitude/polar cap HF communications
have also been impact by increased absorption on 11-May.
-----------------------------------------------------------
4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date T index
11 May 113
Observed Australian Regional MUFs
Cocos Island Region:
Near predicted monthly values during local day.
Enhanced by 30% during local night.
Niue Island Region:
Near predicted monthly values during local day.
Enhanced by 70% during local night.
Northern Australian Region:
Depressed by 20% during local day.
Enhanced by 40% during local night.
Enhanced by 30% after local dawn.
Southern Australian Region:
Depressed by 55% during local day.
Enhanced by 25% during local night.
Antarctic Region (Casey/Davis/Mawson):
Proton event in progress, increased absorption observed.
Monthly T index:
Month T index
Apr 125
May 114
Jun 116
4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date T index MUFs
12 May 100 Near predicted monthly values
13 May 70 15 to 30% below predicted monthly values
14 May 90 Near predicted monthly values
COMMENT: ASWFC Preliminary HF Communications Warning 49 was issued
on 9 May and is current for 10-12 May. ASWFC SWF HF Communications
Warning 50 was issued on 9 May and is current for 10-12 May.
Maximum usable frequencies (MUFs) on UT day 11-May were strongly
depressed by 20-50% during the local day and strongly enhanced
during local night hours in association with geomagnetic storm
activity. Strong spread F was observed during local night hours
for southern Australian region sites. A shortwave fadeout was
observed 11/0101-0405UT in association with the X5 flare. An
extended interval of equatorial ionospheric scintillation was
observed at Darwin, Niue and Weipa 11/1139-2040UT. MUFs are expected
to be initially near predicted monthly values on 12-May, becoming
degraded overnight with further ionospheric depressions, though
not as severe, are likely on 13-May. Frequent shortwave fadeouts
are expected.
-----------------------------------------------------------
5. SPACE ENVIRONMENT SUMMARY
GOES satellite data for 10 May
Daily Proton Fluence >1 MeV: 4.9E+08
Daily Proton Fluence >10 MeV: 1.2E+06
Daily Electron Fluence >2 MeV: 2.10E+06 (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 1%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
X-ray background: C5.2
DSCOVR Satellite Solar Wind Day Averaged Data for 10 May
Speed: 425 km/sec Density: 6.7 p/cc Temp: 68700 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