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Monthly Conditions at the VLA

The following plots show the fraction of time that was most suitable for observing in each VLA band for the one-year period September 2010—August 2011, according to the measured wind speed and API phase rms (opacity is not included). Click any plot to enlarge it. The simultaneous requirements for wind speed and API phase rms used to create these plots correspond to the current table of values in the OPT:

Band	4, P, L	S	C	X	Ku	K	Ka	Q
API (deg)	any	< 60	< 45	< 30	< 15	< 10	< 7	< 5
Wind (m/s)	any	any	any	< 15	< 10	< 7	< 6	< 5

See also the Archival API Plots (monthly plots of API rms phase vs LST Sept 2010—Aug 2011)

January	February	March

April	May	June

July	August	September

October	November	December

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The National Radio Astronomy Observatory and Green Bank Observatory are facilities of the U.S. National Science Foundation operated under cooperative agreement by Associated Universities, Inc.