I first plotted a Hovmoller of only V component winds averaged over -116 to -107W (Lat = 24 to 26N) for the whole of 1983. After looking at this data, I noticed a lot of noise in the northern portions of the graph. As a means to loose that noise and help pick-out patterns associated with surges I restricted the domain to 24 to roughly 33N (longitude held same). An example of this domain is shown below.
Looking at the first Hovmoller plot for this new domain, I noticed that the prevailing southerly winds were not allowing any clear patterns to show up. To compensate for the abundance of southerly, or positive V winds, I calculated the mean-wind for the year to provide a dividing point in the data. On the next Hovmoller, warm colors, i.e., white to red, will signify above average winds and cool colors, i.e., white to blue, will signify below average winds. A black contour interval is added to provide reference to the 0 m/s2 value.
It can be seen by comparing the winds and precipitation, Hovmoller over the same year and domain as V winds, that the two variables show quite close temporal agreement with one another. Though these results should be expected, it is of importance to note this agreement now so that later analysis can use winds as a parameter with confidence.
-jamie
Jamie, interesting analysis that gets at the correlation of southerly wind with precipitation. I wonder if we could show this for the entire period of record - to show the strong reliance of southerly wind on precip at any given point over the domain. Hmmm... Maybe a simple correlation map (matrix) of precipitation vs. longitudinally averaged v wind at lags =-4, -3, -2, -1, and 0.
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