[Ips-dsgr] ASWFC Daily Report - 19 May 23 issued 2330 UT on 19 May 2023 [SEC=OFFICIAL]

Regional Warning Centre rwc at ips.gov.au
Sat May 20 09:30:10 EST 2023


SUBJ: ASWFC DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 2330UT/19 MAY 2023
FROM THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE
SUMMARY FOR 19 MAY AND FORECAST FOR 20 MAY - 22 MAY
STATUS INDICATORS SOL:** RED **   MAG:** YELLOW **     ION: GREEN
ASWAS SCALE DESCRIPTION: https://bit.ly/3lmaMBx
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 19 May:  R2

Flares    Max     Fadeout    Freq.  Sectors
  M5.3    0048UT  possible   lower  West Pacific
  M1.6    0312UT  possible   lower  E. Asia/Aust.
  M2.5    0500UT  possible   lower  E. Asia/Aust.
  M2.3    2006UT  possible   lower  East Pacific/
                                    North American

Observed 10.7 cm flux/Equivalent Sunspot Number for 19 May: 165/119


1B. SOLAR FORECAST
             20 May             21 May             22 May
Activity     R1-R2              R1-R2              R1-R2
Fadeouts     Probable           Possible           Possible
10.7cm/SSN   165/119            165/119            160/114

COMMENT: Solar activity on UT day 19-May reached R2 levels. A 
total of 6 M-class flares were observed: M5.3 at 0048 UT, M1 
at 0312 UT, M2.5 at 0500 UT, and an M2.3 at 2006 UT followed 
by an M2.7 at 2026 UT and M1 at 2120 UT. All M-class flares originated 
from new region AR3311 (N18E61, beta). There are currently 8 
numbered sunspot regions on the disk. AR3311 is the most flare 
productive and some minor growth was observed over the past 24 
hours. AR3308 (N11W38, alpha) and AR3310 (S20E49, beta) have 
also shown some minor growth. All other sunspot regions are either 
stable or in decay. Solar activity is expected to be at R1-R2 
levels over 20-22 May. A filament eruption was observed in H-alpha 
imagery from 19/0449 UT from the southwest quadrant. A CME was 
observed from 19/0749 UT, but is not considered geoeffective. 
A larger filament, located near S25W03, has been showing signs 
it may soon lift off the Sun. This filament will be monitored 
closely for any possible subsequent CME activity. N The 10 MeV 
proton flux has returned to background levels. The solar wind 
speed on UT day 19-May was on a general inclining trend and ranged 
from 285 to 365 km/s. The peak total interplanetary magnetic 
field strength (IMF, Bt) reached 16 nT, shortly after a weak 
shock was observed at 2030 UT to indicate the arrival of a recent 
CME. The north-south IMF component (Bz) range was +6 to -15 nT, 
with southward oriented Bz following the weak shock. The solar 
wind speed is expected to remain elevated on 20-21 May, with 
a pair of small coronal holes in the northern hemisphere contributing 
to the high speed winds. The solar wind may begin to decline 
by 22-May.

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

Geomagnetic field for Australian Region 19 May: G0

Estimated Indices 19 May : A   K           
   Australian Region       4   11111222
      Cocos Island         4   11011222
      Darwin               4   11111222
      Townsville           5   11111223
      Learmonth            -   --------
      Alice Springs        4   10111222
      Gingin               3   00100222
      Canberra             2   00000222
      Hobart               3   01000222    

Estimated Antarctic Regional K Indices 19 May :
      Macquarie Island     2   00000122
      Casey                6   22201322
      Mawson               7   01101234

Observed Regional daily pc3 Indices 19 May : 
      Darwin               2   (Quiet)
      Townsville           6   (Quiet)
      Learmonth           11   (Quiet)
      Alice Springs        6   (Quiet)
      Gingin               0   (Quiet)
      Canberra             0   (Quiet)
      Hobart               0   (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 19 May : A 
           Fredericksburg         5
           Planetary              8                         

Observed AFr/Ap Indices 18 May :  A   K
           Fredericksburg         8
           Planetary              4   1100 1211     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
20 May    20    G0-G1
21 May    12    G0
22 May     8    G0

COMMENT: ASWFC Geomagnetic Warning 28 was issued on 19 May and 
is current for 20 May only. G0 geomagnetic conditions were observed 
in the Australian and Antarctic regions on UT day 19-May. Mostly 
G0 geomagnetic conditions are expected over 20-22 May, with possible 
isolated periods of G1 on 20-May due to a recent CME impact.

-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
19 May      Fair-poor      Normal         Fair           

PCA Event : No event.

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
20 May      Normal         Normal-fair    Fair-normal
21 May      Normal         Normal-fair    Fair-normal
22 May      Normal         Normal         Normal-fair

COMMENT: Some degradations to HF communication conditions were 
observed in low latitude regions on UT day 19-May during local 
night hours. Otherwise, generally normal conditions were observed. 
Mostly Normal HF communication conditions are expected over 20-22 
May, with some mild degradations possible during local night 
hours. Shortwave fadeouts are probable.

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


Date   T index
19 May    88

Observed Australian Regional MUFs
   Cocos Island Region:
      Near predicted monthly values.
   Niue Island Region:
      Enhanced by 25% during local day.
      Near predicted monthly values during local night.
   Northern Australian Region:
      Near predicted monthly values.
   Southern Australian Region:
      Near predicted monthly values.
   Antarctic Region (Casey/Scott Base/Davis/Mawson):
      Near predicted monthly values over the UT day.

Monthly T index:
Month  T index
Apr      120
May      87
Jun      88

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
20 May    90    Near predicted monthly values to 15% depressed
21 May    85    Near predicted monthly values to 10% depressed
22 May    90    Near predicted monthly values

COMMENT: ASWFC SWF HF Communications Warning 47 was issued on 
19 May and is current for 20-22 May. Maximum usable frequencies 
(MUFs) on UT day 19-May were near predicted monthly values in 
the Australian region. Spread-F was observed at Hobart; sporadic-E 
was observed at Townsville, and degraded conditions were observed 
at Darwin during local night hours. MUFs are expected to be near 
predicted monthly values over 20-22 May, with some mild depressions 
possible. Shortwave fadeouts are probable.

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

GOES satellite data for 18 May
       Daily Proton Fluence >1 MeV:   7.8E+04
       Daily Proton Fluence >10 MeV:  3.6E+04
       Daily Electron Fluence >2 MeV: 2.40E+06   (normal fluence)
Electron Fluence Daily Deep Dielectric Discharge Probability: 1%
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.
       X-ray background: C1.5

DSCOVR Satellite Solar Wind Day Averaged Data for 18 May
Speed: 438 km/sec  Density:    2.8 p/cc  Temp:   152000 K  Bz:   1 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