A

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U

U/S - Unservicable
UAB - Until advised by ...
UCP -   Unit Control Position
UDDF - Up and down drafts
UFN - Until further notice
UIR - Upper flight information region
UKMET -   United Kingdom METeorological Agency
ULJ -   Upper Level Jet
UN - Unable
UNA - Unable
UNAVBL - Unavailable
UNEC - Unnecessary
UNKN - Unknown
UNL - Unlimited
UNREL - Unreliable
UNRELBL - Unreliable
UNRSTD - Unrestricted
UNSATFY - Unsatisfactory
UNSBL - Unseasonable
UNSTBL - Unstable
UNSTDY - Unsteady
UNSTL - Unsettle
UNSTLD - Unsettled
UNUSBL - Unusable
UPDFTS - Updrafts
UPR - Upper
UPSLP - Upslope
UPSTRM - Upstream
URG - Urgent
USACE -   U.S. Army Corps of Engineers
USBL - Usable
USBR -   U.S. Bureau of Reclamation
USFS -   U.S. Forest Service
USGS -   U.S. Geological Survey
UT - Utah
UTC -   Coordinated Universal Time
UV -   Ultraviolet
UVM -   Upward Vertical Motion.
UVV -   Upward Vertical Velocity
UVVS - Upward vertical velocities
UWNDS - Upper winds  


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