30 minutes after lightning is observed within of the launch pad or the flight path. Unique for Crew Dragon launches of the Falcon 9: weather downrange has a high chance or is violating splashdown limits (wind, wave, lightning, and precipitation limits) in case of a launch escape Space Shuttle Weather The weather conditions NASA required during countdown and launch were specified for "prior to loading external tank propellant" and "after loading propellant has begun". Weather forecasts were provided by the 45th Weather Squadron at nearby Patrick Air Force Base with concerns such as thunderstorms, winds, low cloud ceilings, or anvil clouds noted in the report. Prior to loading propellant Tanking was not to begin if the 24-hour average temperature had been below , the wind was observed or forecast to exceed for the next three-hour period, or there was a forecast to be greater than a 20% chance of lightning within five nautical miles of the launch pad during the first hour of tanking. After propellant loading was underway After tanking began, the countdown must not be continued, nor the Shuttle launched, if any of the following weather criteria were exceeded: Temperature Once propellant loading had begun, the countdown was to be stopped if the temperature remained above for more than 30 consecutive minutes. The minimum temperature the countdown may proceed at was determined by a table of temperatures determined by wind speed and relative humidity ranging from (high humidity, high winds) to (low humidity, low winds). In no case was the space shuttle to be launched if the temperature was degrees or colder. Wind For launch the wind constraints at the launch pad varied slightly for each mission. The peak wind speed allowable was . However, when the wind direction was between 100 degrees and 260 degrees, the peak speed varies and may be as low as . Precipitation None was allowed to exist at the launch pad or within the flight path. References External links Launch Weather Forecast for Cape Canaveral from Patrick Space Force Base Example pre-launch weather report from MAVEN pre-launch press conference Spaceflight