[Ips-dsgr] SWS Daily Report - 17 September 21 issued 2353 UT on 17 Sep 2021

rwc rwc at ips.gov.au
Sat Sep 18 09:53:10 EST 2021


SUBJ: SWS DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/17 SEPTEMBER 2021 BY Space Weather Services
FROM THE AUSTRALIAN SPACE FORECAST CENTRE
SUMMARY FOR 17 SEPTEMBER AND FORECAST FOR 18 SEPTEMBER - 20 SEPTEMBER
STATUS INDICATORS SOL:GREEN   MAG:GREEN     ION: ** YELLOW **
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 17 Sep:  Low

Flares: none.

Observed 10.7 cm flux/Equivalent Sunspot Number for 17 Sep:  73/9


1B. SOLAR FORECAST
             18 Sep             19 Sep             20 Sep
Activity     Very low to low    Very low to low    Very low to low
Fadeouts     None expected      None expected      None expected
10.7cm/SSN    78/17              78/17              76/14

COMMENT: Solar activity was low on UT day 17 September with a 
C3.5 flare at 17/0420 UT from over the southeast limb. A type 
II sweep was observed 17/0417-0427 UT with estimated shock speed 
of 582 km/s. The visible disk of the Sun is spotless with no 
active regions. Solar activity is expected to be very low to 
low on 18-20 September. A southeast CME was first observed in 
LASCO C2 at 0428 UT and is likely associated with the C3.5 flare. 
A narrow CME observed at 0438 UT on the northeast limb may be 
associated with a prominence eruption on the limb. There was 
also a very faint CME signature to the south in LASCO C3 at 0454 
UT. There was a filament eruption in the southeast quadrant ending 
around 17/0130 UT which may have been the origin of this CME 
but there are no STEREO A images to confirm at this stage. A 
glancing blow early on 20 Sep is possible from the CME associated 
with the C3.5 flare. On UT day 17 September, a step occurred 
in solar wind parameters at 0130 UT, probably signalling the 
arrival of the 13 September CME. The solar wind speed range was 
290 km/s to 419 km/s. The total IMF (Bt) peaked at 15 nT and 
the north-south component (Bz) varied in the range -14/+12 nT, 
mostly southward after 0130 UT. Over UT day 18 September the 
solar wind parameters are expected to be mildly elevated due 
to a coronal hole wind stream and the subsiding effects of the 
CME. Conditions should be settled on 19 September.

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

Geomagnetic field for Australian Region 17 Sep: Quiet to Active

Estimated Indices 17 Sep : A   K           
   Australian Region      12   22132343
      Cocos Island         8   22122332
      Darwin              11   33122333
      Townsville          12   33132333
      Learmonth           15   32133344
      Alice Springs       12   22132343
      Gingin              13   22133343
      Canberra            11   22132243
      Hobart              13   22043243    

Estimated Antarctic Regional K Indices 17 Sep :
      Macquarie Island    27   23065443
      Casey               14   34232333
      Mawson              34   35223466

Observed Regional daily pc3 Indices 17 Sep : 
      Darwin               0   (Quiet)
      Townsville           0   (Quiet)
      Learmonth            0   (Quiet)
      Alice Springs        0   (Quiet)
      Gingin               0   (Quiet)
      Canberra             0   (Quiet)
      Hobart              14   (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 Sep : A 
           Fredericksburg         0
           Planetary              0                         

Observed AFr/Ap Indices 16 Sep :  A   K
           Fredericksburg         3
           Planetary              3   3     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
18 Sep    13    Quiet to Active. Chance of an isolated minor 
                storm period.
19 Sep     8    Quiet to Unsettled
20 Sep     7    Quiet

COMMENT: On UT day 17 September, geomagnetic conditions in the 
Australian region were quiet to active. In the Antarctic region, 
quiet to major storm levels were observed. A weak (8 nT) impulse 
was observed at 17/0219 UT in the SWS magnetometer data. Geomagnetic 
conditions are expected to be at quiet to active with a chance 
of an isolated minor storm period on 18 September as the CME 
effects pass and an expected weak coronal hole wind stream. Mostly 
quiet conditions are expected on 19-20 September.

-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
17 Sep      Normal         Normal         Normal         

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
18 Sep      Normal-fair    Normal-fair    Normal-fair
19 Sep      Normal         Normal         Normal-fair
20 Sep      Normal         Normal         Normal

COMMENT: Normal to fair conditions are expected on 18 September 
with mild to moderate MUF depressions. Conditions on 19-20 September 
are expected to be mostly normal.

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


Date   T index
17 Sep    14

Observed Australian Regional MUFs
   Cocos Island Region:
      Near predicted monthly values during local day.
      Depressed by 25% during local night.
   Niue Island Region:
      No data available.
   Northern Australian Region:
      Depressed by 15% during local day.
      Depressed by 20% during local night.
   Southern Australian Region:
      Near predicted monthly values.
   Antarctic Region (Casey/Scott Base/Davis/Mawson):
      Enhanced by 30% over the UT day.

Monthly T index:
Month  T index
Aug      14
Sep      27
Oct      30

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
18 Sep     5    Near predicted monthly values/depressed 15 to 
                25%
19 Sep    15    Near predicted monthly values
20 Sep    15    Near predicted monthly values

COMMENT: MUFs in the Australian region on UT day 17 September 
were mostly near predicted monthly values. Some moderately depressed 
MUFs were observed in the Cocos Island region during the local 
night. MUFs in the Australian region on UT days 18-20 September 
are expected to be near predicted monthly values to mildly depressed. 
Moderate depressions likely on 18 September.

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

GOES satellite data for 16 Sep
       Daily Proton Fluence >1 MeV:   NA
       Daily Proton Fluence >10 MeV:  NA
       Daily Electron Fluence >2 MeV: NA
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: NA

DSCOVR Satellite Solar Wind Day Averaged Data for 16 Sep
Speed: 324 km/sec  Density:    6.9 p/cc  Temp:   186000 K  Bz:   0 nT

(Courtesy Space Weather Prediction Center, Boulder USA)
-----------------------------------------------------------

Space Weather Services              email: asfc at bom.gov.au
Bureau of Meteorology
PO Box 1386                         WWW: http://www.sws.bom.gov.au
Haymarket NSW 1240  AUSTRALIA       FTP: ftp://ftp-out.sws.bom.gov.au
tel: +61 2 9213 8010                fax: +61 2 9213 8060 

IMPORTANT: This e-mail, including any attachments, may contain,
confidential or copyright information.  The views expressed in 
this message are those of the individual sender, unless 
specifically stated to be the views of SWS.  If you are not 
the intended recipient, please contact the sender immediately 
and delete all copies of this e-mail and attachments. 
To unsubscribe from an IPS mail list either send an email to 
"MAIL_LIST"-leave at ips.gov.au or go to
http://www.sws.bom.gov.au/mailman/listinfo/"MAIL_LIST".
Information about training can be obtained from
http://www.sws.bom.gov.au/mailman/listinfo/ips-training.
General information is available from
http://www.sws.bom.gov.au/mailman/listinfo/ips-info.




More information about the ips-dsgr mailing list