NASA StreaM

## Community Coordinated Modeling Center Database Of Notifications, Knowledge, Information (CCMC DONKI) ## Message Type: Weekly Space Weather Summary Report for May 13, 2026 - May 19, 2026 ## ## Message Issue Date: 2026-05-20T19:56:50Z ## Report Coverage Begin Date: 2026-05-13T00:00Z ## Report Coverage End Date: 2026-05-19T23:59Z ## Message ID: 20260520-7D-001 ## ## Disclaimer: NOAA's Space Weather Prediction Center is the United States Government official source for space weather forecasts. This "Experimental Research Information" consists of preliminary NASA research products and should be interpreted and used accordingly. ## Summary: Solar activity was at moderate levels during this reporting period with 4 M-class flares, 1 O-type CME, and 10 C-type CMEs (see details below). Based on preliminary analysis by the Moon to Mars Space Weather Analysis Office and heliospheric modeling carried out at NASA Community Coordinated Modeling Center, it was estimated that the following CMEs were predicted to impact missions near Earth: CME Starting time | Predicted Impacts (plus minus 7 hours) ----------------------------------------------------------------------------- 2026-05-16T16:36Z NASA missions near Earth at 2026-05-19T00:00Z (glancing blow), Kp index 3-5 (below minor to minor) (see notification 20260516-AL-006). The arrival of this CME was likely detected at L1 around 2026-05-19T06:31Z. It was also estimated that the following CMEs were predicted to impact the listed locations: CME Starting time | Predicted Impacts (plus minus 7 hours) ----------------------------------------------------------------------------- 2026-05-13T22:24Z Parker Solar Probe at 2026-05-15T19:33Z, Juice at 2026-05-19T22:00Z (glancing blow), Mars at 2026-05-18T22:00Z (glancing blow), Psyche at 2026-05-18T22:00Z (glancing blow), and STEREO A at 2026-05-17T10:00Z (glancing blow) (see notification 20260514-AL-001). 2026-05-16T08:09Z Mars at 2026-05-20T08:00Z (glancing blow), Psyche at 2026-05-20T06:00Z (glancing blow), and Solar Orbiter at 2026-05-20T00:00Z (glancing blow) (see notification 20260516-AL-005). 2026-05-16T16:36Z Europa Clipper at 2026-05-20T21:00Z (glancing blow) and OSIRIS-APEX at 2026-05-19T16:00Z (glancing blow) (see notification 20260516-AL-006). The highest value of Kp = 6.33 occurred during the synoptic period 2026-05-15T21:00Z to 2026-05-16T00:00Z (see notifications 20260516-AL-001, 20260516-AL-002). This enhancement in geomagnetic activity was associated with the interplanetary shock detected at L1 by ACE and DSCOVR at 2026-05-15T07:14Z (see notification 20260515-AL-001) which was associated with the arrival of the coronal hole high speed stream detected by ACE and DSCOVR at L1 on 2026-05-15. The > 2.0 MeV energetic electron flux in the Earth's outer radiation belt crossed the threshold level of 1000 pfu starting at 2026-05-16T15:20Z (see notifications 20260516-AL-003, 20260516-AL-004, 20260518-AL-001). This elevation of energetic electron flux levels was likely associated with the arrival of a coronal hole high speed stream detected at L1 by ACE and DSCOVR on 2026-05-15. The energetic proton flux of >10 MeV protons detected at GOES and the 13-100 MeV protons at STEREO A were all at background levels for the entire reporting period. Space Weather Impact: Space weather impacts on NASA spacecraft are expected to have been moderate this reporting period due to the elevated energetic electron flux in the Earth's outer radiation belt described above. ##Events: Flares (M-class and above) Date Start Stop Peak Class Location 2026-05-16 15:50:00 16:22:00 16:12:00 M1.9 N22W17 ( 14436 ) 2026-05-16 16:22:00 16:34:00 16:29:00 M1.3 N18W15 ( 14436 ) 2026-05-16 17:39:00 17:44:00 17:42:00 M1.9 N21W90 ( 14435 ) 2026-05-17 03:29:00 03:42:00 03:39:00 M1.4 N22W97 ( 14435 ) CMEs (>500 km/s): Earth directed: Starting time Speed (km/s) Type Direction (LON/LAT in HEEQ) Half-Angle width (degrees) Detecting spacecraft (real-time) 2026-05-16T16:36Z ~1201 O 9/37 22 SOHO, STEREO A, GOES Non-Earth directed (POS = Plane Of Sky): Starting time Speed (km/s) Type Direction (LON/LAT in HEEQ) Half-Angle width (degrees) Detecting spacecraft (real-time) 2026-05-13T03:12Z ~736 C 102/-31 11 SOHO, STEREO A, GOES 2026-05-13T22:24Z ~519 C 87/26 34 SOHO, STEREO A, GOES 2026-05-14T20:12Z ~501 C -20/34 15 SOHO 2026-05-15T02:00Z ~522 C 49/-46 23 SOHO, STEREO A 2026-05-15T14:24Z ~564 C -75/17 29 SOHO, STEREO A, GOES 2026-05-16T05:00Z ~503 C 90/44 21 SOHO, STEREO A, GOES 2026-05-16T08:09Z ~548 C 175/2 40 STEREO A 2026-05-17T10:24Z ~508 C -40/37 10 SOHO, STEREO A 2026-05-18T22:00Z ~594 C NONE(POS)/3 10 SOHO, GOES 2026-05-19T11:01Z ~564 C -26/32 20 SOHO, STEREO A ## Space Weather Outlook: ## Outlook Coverage Begin Date: 2026-05-20T00:00Z ## Outlook Coverage End Date: 2026-05-26T23:59Z Solar activity is expected to be at low to moderate levels during the outlook period. There are currently four numbered Active Regions on the Earth-facing disk. Active Region 14436 (N18W72) produced M-class flaring during the reporting period and may produce similar levels of flaring activity during the outlook period. Geomagnetic activity is expected to be at low levels during the outlook period. A southern coronal hole started crossing the central meridian on 2026-05-20 (as seen in available imagery from SDO/AIA 193) and may reach geoeffective longitudes on or around 2026-05-23. ## Notes: SCORE CME typification system: S-type: CMEs with speeds less than 500 km/s C-type: Common 500-999 km/s O-type: Occasional 1000-1999 km/s R-type: Rare 2000-2999 km/s ER-type: Extremely Rare >3000 km/s