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Starlink-L27 - L-1 Day

Falcon 9

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Valid Period

May 9, 2021 05:42 - 07:34 UTC (01:42 - 03:34 ET)

Issued

Sat May 8, 2021 at 12:00 UTC (08:00 ET)

Forecast Discussion

Space Launch Delta 45

High pressure continues to move across the southeastern US. Slightly cooler and drier air has begun to overspread the area. There will likely be scattered cumulus clouds later this afternoon and evening. Another storm system is developing over the south central US which will begin to increase winds slightly over the area as it develops this weekend. Winds over the Space Coast as well as the recovery area look to be on the light side. The overall threat for a delay looks to be small but the main weather concern for the primary day will be from the Cumulus Cloud Rule. In the event of a delay, the storm system over the central US moves into the Mississippi Valley late Sunday into early Monday morning. As this happens, the surface pressure gradient tightens and this will cause winds to increase. This will occur both at the Space Coast as well as the recovery area. As with late Saturday/early Sunday, expect scattered cumulus clouds. The primary weather concerns for Monday morning are the Cumulus Cloud Rule as well as Liftoff Winds.

Primary Launch Date

Launch Day

Primary Window

80%
PGO

Primary Concerns

  • Cumulus Cloud Rule

Additional Risk Criteria

CriteriaRisk Level
Upper-Level Wind ShearLOW
Booster Recovery WeatherLOW
Solar ActivityLOW

Backup Opportunities

24-Hour Delay

Backup Window

70%
PGO

Primary Concerns

  • Cumulus Cloud Rule
  • Liftoff Winds

Additional Risk Criteria

CriteriaRisk Level
Upper-Level Wind ShearLOW
Booster Recovery WeatherMOD
Solar ActivityLOW