the bee

al
winds and observed winds during the period of HAVO were within

these observational limits, On the last specific wind forecast
igsued at H minus 8 hours, there were ten (10) winds forecast to
be above 10 mots which can be compared with the observed winds

taken fram the CURTISS at BRAVO hour.

Of these ten (10) winds,

siz (6) differed by 10 degrees, two (2) by 20 degrees, one (1)
by 30 degrees and one (1) by 40 degrees.

80 per cent of the

forecast winds which can be checked in the imnediete locale were
within observational limits imposed by the equipment itself.

The

errers of 30 desrees and 40 degrees were the forecasts for the
levels immediately above and below 10,000 feet.
CONCLUSIONS:
ae

Weather conditions during the five days prior to BRAVO day were

indicative of a favorable trend for BRAVO, involving on an average,

ERAVO minus 2 and FRAVO minus 1 days were especially favorable

fron a fallout point of view.

The weather situation presented at z

minus 6 hours for a 2) hour period was setisfactary; however, an unfavorable trend was predicted to occur during the following 24 hous
since northwest winds were forecast for the 10,000 to 20,000 foot
levels. This trend wes borne out by leter observations.
be

The forecast wind directions were well within the normal forecast

error, which must be anticipated.

Forecasts of the seme precisicn as

those mage in ereas of deuse observation networks cannot be expected

in this ereae

The forecasts of rincs eloft for BRAVO were, neverthe-

less, approaching the limits of Eiman ability which the ext et presext
allots.

Ce

ihe

above.

ee

easterly winds below 15,000 feet, with winds of a southerly component

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