# Adjusting opacity in map overlays

I am currently working with rainfall data from hurricane Harvey in order to better understand how to allocate resources in the event of another disaster. I want to accomplish a few things given this data set.

Import["http://www.srh.noaa.gov/data/ridge2/Precip/qpehourlyshape/\
2017/201708/20170826/nws_precip_2017082607.tar.gz"]


The following are the elements of the data set:

  {"Centering", "CentralScaleFactor", "CoordinateSystem", \
"CoordinateSystemInformation", "Data", "Datum", "Graphics", \
"GraphicsList", "GridOrigin", "InverseFlattening", "LayerNames", \
"LayerTypes", "LinearUnits", "Projection", "ProjectionName", \
"ReferenceModel", "SemimajorAxis", "SemiminorAxis", "SpatialRange", \
"StandardParallels"}


What I want to do is to scale down the opacity of the points on the graph based on the heights of the rainfall (lower opacity for lower rainfall heights) so I can get a clear image of the hurricane. I also want to show rainfall for only Texas and neighboring states. This may seem like a general question but I checked the documentation and I am new to $Mathematica$ and working with large data sets like this one. Thank you to whomever is taking the time to answer or edit this question.

• If you provide the code of how you generate the picture would be fine for helping you. – José Antonio Díaz Navas Nov 13 '17 at 19:39
• Have you take a look at this? – José Antonio Díaz Navas Nov 13 '17 at 19:41
• The picture is generated from the single import command seen above. If you type "Elements" after the link in the import command the data set has its elements listed above. – hwhorf Nov 13 '17 at 20:15
• So do I have to understand that from the information of the picture, you get all the data of the elements, and you have in other set the rainfall for each point? – José Antonio Díaz Navas Nov 13 '17 at 20:18
• Here is the link from where I got the data set from: roadtolarissa.com/hurricane This is from data science weekly. The author of the article was working with the same data set in r. Is there a similar way to do this in mathematica? – hwhorf Nov 13 '17 at 20:22