[sci.space.shuttle] KSC Weather Report for 05/20/91

yee@trident.arc.nasa.gov (Peter E. Yee) (05/21/91)

          TO:   PIOS/PRESS

          FROM: George Diller/NASA-KSC
                407-867-2468/FTS 823-2468

                              L-2 Day Weather Forecast for STS-40
                              UPDATED 2:30 p.m.
                              Conditions expected on Wednesday, 5/22/91

          Synopsis:   Low pressure will cover the central and western Gulf
          of Mexico while an upper level low pressure trough approaches
          Florida.  The trough will create offshore showers, while the Gulf
          low located adjacent to Atlantic high pressure will create a
          gradient that generates strong surface winds.  Main concerns are
          the increase in winds, a chance of showers, and possible ceilings
          below the 8,000-foot minimum.

          At 8:00 a.m. on Wednesday morning conditions are forecast to be:

          Clouds:   3,000 to  6,000 scattered cumulus      (50% sky cover)
                    8,000 to 11,000 scattered altocumulus  (40% sky cover)
                   25,000 to 28,000 broken cirrostratus    (60% sky cover)

          Visibility: 7 miles

          Wind - Pad 39B: ESE-14 knots, gusts 20 knots

          Temperature:  76 degrees

          Dewpoint:     73 degrees

          Humidity:     86%

          Precipitation: chance of showers


          Probability of launch weather criteria violation at the beginning
          of the launch period: 40%

          Probability of launch weather criteria violation over the
          duration of the launch period: 30%

          Probability of tanking constraint violation: 5%

          Chance of violation at launch time on Thursday: 40%
                                                overall window 30%

                                                Friday:  30%
                                                overall window: 20%

          Developed by Cape Canaveral Forecast Facility
          USAF Air Weather Service  5/20/91