Weekly Bulletin on Solar and Geomagnetic Activity
               Highlights on 23 - 29.04.2018,
                Forecast on 30.04 - 06.05.2018,
            Carrington Rotation 2003 (19,22.04.2018)
            Earth out of ecliptic (-2.5 - -2.1) deg. 
             (S28 - N25 is zone o geoeffectiveness)

THE SUNSPOT-FORMING ACTIVITY OF THE SUN WAS ON VERY LOW LEVEL,
THE VISIBLE DISK WAS SPOTLESS 28 -29.04 (69d ON 2018). THE ES-
TIMATED, MOST LIKELY WEEKLY AVERAGE VALUE OF THE RELATIVE SUN-
SPOT NUMBER IN THE INTERNATIONAL SYSTEM (old) FOR  THE PERIOD
W = 007+5/-7 (Wn = 011+10/-11). ON THE VISIBLE DISK ONE SMALL, 
QUITE SUNSPOT GROUP HAS BEEN OBSERVED. 

 NEXT WEEK THE LEVEL OF SUNSPOT ACTIVITY  WILL BE ON THE VERY 
LOW LEVEL AND WITH HIGH PROBABILITY THE SUN  WILL BE SPOTLESS. 
LIKELY WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT NUMBER IN 
THE INTERNATIONAL SYSTEM (old) FOR THE NEXT WEEK IS W=010+10/
-10.  

 FLARE ACTIVITY WAS ON THE VERY LOW LEVELS ON PERIOD. NO EJEC-
TA OF SOLAR FILAMENTS AND TWO CORONAL MASS EJECTIONS (26  AND 
29.04) HAVE BEEN OBSERVED.
----------------------------------------------------------------------
FLARES FROM M1 CLASSES
        to   tm    te   local.     Class   E(1-8A)  AR   RII/IV   CME
                                 X-ray/Ïp  J/m-2
DSF     
        to      te  localization   l × ÇÒÁÄ.  Fl    AR    CME/to
---------------------------------------------------------------------
NEXT WEEK THE FLARE ACTIVITY IS EXPECTED AT VERY LOW LEVELS.

ON THE VISIBLE SOLAR DISK THE FOLLOWING CORONAL HOLES WERE OBSERVED:
---------------------------------------------------------------------
  sign   N end   E end   S end  W end    Sch    EE    R  G  Space Obser.
Sch - CH Square in Mm**2 (in square megameters) near the central meri-
dian on http://sdowww.lmsal.com/suntoday/; n/d - no data;
R - solar rotations; EE-date of possible geomag. disturbance in the 
Earth's environment. G(0-5)-geoeffectivity in last solar rotation on
the middle latitudes. A-active geomagnetic condition.
------------------------------------------------------------------------

 AFTER 27.04/0100 UT EARTH IS IN "+" SECTOR OF INTERPLANETARY MAG-
NETIC FIELD. NEXT SECTOR BOUNDARY +/- THE EARTH MUST PASS 9.05.

APRIL     23     24     25     26     27     28     29   APRIL
Wus      022    019    017    014    011    000    000 
F10.7    074    073    071    069    069    070    071 
èbcg    á4.7   á4.3   á3.4   á3.1   á2.5   á2.6   á2.6   GOES
Sp       080    050    050    020    010    000    000   msh   
N                                                   
IMF       -      -      -      -     -/+     +      +   DSCOVR   
Å>2   7.3E+8 4.9E+8 1.6E+8  17å+8 1.2å+8 5.4å+7 5.5å+7   GOES
Ie>2   21958  15976  11840   4623   4841   2359   1250   pfu 
Ap        6      5      4      4      5      4      4    nô  
Dst                                                      nô KIOTO
Amsc      8      5      4      5      6      4      5    nô IZMIRAN 
--------------------------------------------------------------------
Å>2 - Daily Electron Fluency e/(cm2-ster-day) with E>2 MeV.
Ie>2 - the maximum intensity of electron flux in geostationary or-
bits in days according to GOES15 in (electrons/cm2.s.sr) for events
> 1000 pfu.

THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT HAS 
BEGAN AT 10.04/0430 UT AND OBSERVED 10.03 - 29.04.  
 
 NEXT WEEK THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS 
ORBIT IS NOT EXPECTED4.

GEOMAGNETIC CONDITION  WAS UNSETTLED AND QUITE.   

NEXT WEEK THE GEOMAGNETIC CONDITION SHOULD BE QUITE AND UNSETTLED.

HIGHLIGHT AND FORECAST COMPOSED FROM DATA:
NOAA SWPC, BOULDER, USA               http://www.swpc.noaa.gov,
THE SOLAR INFLUENCES DATA ANALYSIS CENTRE, 
SIDC, BRUSSELS, BELGIUM               http://sidc.oma.be/index.php3, 
THE IZMIRAN, MOSCOW, TROITSK, RUSSIA  http://www.izmiran.ru
                                                          V. Ishkov