[Ips-dsgr] ASWFC Daily Report - 26 October 23 issued 2332 UT on 26 Oct 2023 [SEC=OFFICIAL]

rwc rwc at ips.gov.au
Fri Oct 27 10:32:42 EST 2023


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/26 OCTOBER 2023
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 26 OCTOBER AND FORECAST FOR 27 OCTOBER - 29 OCTOBER
STATUS INDICATORS SOL:** YELLOW **   MAG:GREEN     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 26 Oct:  R1

Flares: M1 at 2315 UT

Observed 10.7 cm flux/Equivalent Sunspot Number for 26 Oct: 126/79


1B. SOLAR FORECAST
             27 Oct             28 Oct             29 Oct
Activity     Low to moderate    Low to moderate    Low
Fadeouts     Possible           Possible           None expected
10.7cm/SSN   126/79             126/79             130/84

COMMENT: Solar activity on UT day 26-Oct was R1, with several 
low level C-class flares and one R1 level radio blackout at 26/2315 
UT from near AR3473. At the time of writing this flare has not 
peaked. There are currently five numbered sunspot regions on 
the solar disk. AR3472 (N20E43, beta) and AR3473 (N14E64, beta) 
have grown from being mostly plage to having some very small 
and simple spots and were responsible for most of the C-class 
solar flares in the past 24 hours. AR 3471 (S22W32, beta) has 
shown some minor growth over the period as well, and also contributed 
to the C-class flaring, but all other sunspots are stable. Overall, 
the sunspot regions on the disk are not currently significantly 
complex and solar activity over 27-29 Oct is expected to be R0 
with a chance of R1. 

A CME was observed on the northwest solar limb from 25/2336 UT, 
although this event is not considered to be Earth-directed due 
to its location. A filament eruption was observed on the northeast limb 
from 26/2250 UT near AR3473 associated with the R1 flare. A CME 
is possible, but the event will be analysed when further imagery 
becomes available. No other CMEs were observed on 26-Oct.

A weak CME may have passed close to Earth or had a glancing impact 
on 26-Oct, possibly from a CME first seen on 21-Oct. Additionally,
 the small coronal hole currently near W50 may have connected with Earth. 
The solar wind speed on UT day 26-Oct was on a steady increase until 
26/1320 UT, from when it increased notably. The solar wind speed ranged
 between 330 to 550 km/s and is currently near 500 km/s. The peak total
 interplanetary field strength (IMF, Bt) was 13 nT and the north-south
 IMF component (Bz) range was +9 to -12 nT. Bz was oriented southward 
for several sustained periods on 26-Oct. The solar wind parameters 
are expected to remain enhanced on 27-Oct, returning to background levels 
over 28-29 Oct. There is a large coronal hole currently near 
the central meridian, however this is not expected to affect 
Earth in the current 3-day forecast period.

-----------------------------------------------------------
2A. MAGNETIC SUMMARY

Geomagnetic field for Australian Region 26 Oct: G0

Estimated Indices 26 Oct : A   K           
   Australian Region      16   23344233
      Cocos Island        10   23233222
      Darwin              15   23244233
      Townsville          17   23344243
      Learmonth           17   33244333
      Alice Springs       16   23344233
      Gingin              16   32234244
      Canberra            17   23344243
      Hobart              18   23344334    

Estimated Antarctic Regional K Indices 26 Oct :
      Macquarie Island    23   22165333
      Casey               26   45533334
      Mawson              43   34345475

Observed Regional daily pc3 Indices 26 Oct : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            2   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin               2   (Quiet)
      Canberra             4   (Quiet)
      Hobart              13   (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 26 Oct : A 
           Fredericksburg        15
           Planetary             19                         

Observed AFr/Ap Indices 25 Oct :  A   K
           Fredericksburg         3
           Planetary              2   0000 2111     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
27 Oct    12    G0, slight chance G1
28 Oct    10    G0
29 Oct     8    G0

COMMENT: ASWFC Geomagnetic Warning 62 was issued on 26 October 
and is current for 26-27 Oct. G0 geomagnetic conditions were 
observed in the Australia region on UT day 26-Oct, although there 
were several periods where the Australian K-index reached 4 (under 
but close to the G1 threshold). Mostly G0-G2 geomagnetic conditions 
were observed in the Antarctica region, but with an isolated 
period of G3 at Mawson. Geomagnetic conditions are expected to 
be G0 over 27-29 Oct, although there is a slight chance for G1.

-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
26 Oct      Normal-fair    Normal         Normal         

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
27 Oct      Normal-fair    Normal-fair    Fair
28 Oct      Normal         Normal-fair    Normal-fair
29 Oct      Normal         Normal         Normal

COMMENT: HF radio propagation conditions were mostly normal on 
26-Oct, with some mild degradations during local night hours 
in low latitudes. Mildly degraded HF conditions may be expected 
over 27-28 Oct, particularly during local night hours. Conditions 
are expected to return to normal by 29-Oct.

-----------------------------------------------------------
4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY


Date   T index
26 Oct   133

Observed Australian Regional MUFs
   Cocos Island Region:
      Enhanced by 40% during local day.
      Enhanced by 35% during local night.
   Niue Island Region:
      Enhanced by 15% during local day.
      Near predicted monthly values during local night.
   Northern Australian Region:
      Enhanced by 15% during local day.
      Near predicted monthly values during local night.
   Southern Australian Region:
      Enhanced by 15% during local day.
      Enhanced by 20% during local night.
   Antarctic Region (Casey/Davis/Mawson):
      Near predicted monthly values over the UT day.

Monthly T index:
Month  T index
Sep      104
Oct      98
Nov      96

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
27 Oct   120    Near predicted monthly values to 10-15% depressed
28 Oct   120    Near predicted monthly values to 10-15% depressed
29 Oct   130    Near predicted monthly values to 10-15% enhanced

COMMENT: ASWFC SWF HF Communications Warning 105 was issued on 
26 October and is current for 27-28 Oct. Maximum usable frequencies 
(MUFs) in the Australian region on UT day 26-Oct were near predicted 
monthly values to 20% enhanced. Sporadic-E was observed at low 
latitude regions during local dusk and night hours. MUFs are 
expected to be near predicted values, with possible depressions 
of 10-15% over 27-28 Oct due to some mild geomagnetic activity. 
MUFs are expected to be near predicted monthly values to 10-15% 
enhanced by 29-Oct.

-----------------------------------------------------------
5. SPACE ENVIRONMENT SUMMARY

GOES satellite data for 25 Oct
       Daily Proton Fluence >1 MeV:   3.5E+04
       Daily Proton Fluence >10 MeV:  1.9E+04
       Daily Electron Fluence >2 MeV: 7.20E+06   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 1%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: B5.4

DSCOVR Satellite Solar Wind Day Averaged Data for 25 Oct
Speed: 327 km/sec  Density:    6.5 p/cc  Temp:    16100 K  Bz:   0 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