National Weather Service United States Department of Commerce

Heavy rain and flash flooding possible in portions of the Southwest this weekend

An upper-level low in the Southwest U.S. will act as a trigger for thunderstorms this weekend. The area of greatest concern is in New Mexico, southeast Utah and portions of southern Colorado. Storms will be slow moving and could bring several rounds of rain to the same areas. Rainfall amounts may exceed 3 inches in localized areas. Flash Flood Watches are in effect. Read More >

Percentile JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
Max X X X X X X X X X X X X
99th X X X X X X X X X X X X
75th X X X X X X X X X X X X
50th X X X X X X X X X X X X
25th X X X X X X X X X X X X
+2sd X X X X X X X X X X X X
+3sd X X X X X X X X X X X X

Methodology

These plots are produced from data compiled by Matt Bunkers at WFO Rapid City

The Storm Prediction Center produces precipitable water climatology for each sounding location.

The gridded precipitable water plots (above) were created for the maximum, 99th percentile, 75th percentile, 50th percentile, and +2SD values.  A separate GIS point shapefile was created for each of these categories, based on the latitude/longitude values of the sounding locations for each month.  The point shapefiles were then interpolated to the gridded raster format using the following specifications:

   a)  Kriging interpolation method
   b)  Semivariogram:  Circular
   c)  Number of points:  6
   d)  Grid resolution:  0.1 degrees

Due to increasing uncertainty in interpolated data at increasing distances from the point data source, caution should be used when taking a value from the precipitable water maps. Because of this, the border of the continentual Unites States was used to clip the completed grids.

The data on these plots has changed since the original plots were produced in 2011. This is due to a change in the interpolation method (to a geostatistical technique) as well as the additional of 3 more years of sounding data.


Change Log

The data on these plots has changed since the original plots were produced in 2011. This is due to a change in the interpolation method (to a geostatistical technique) as well as the additional of 3 more years of sounding data.


Attributions

These plots are produced from data compiled by Matt Bunkers at WFO Rapid City

The Storm Prediction Center produces precipitable water climatology for each sounding location.


Contact Information

Questions or comments should be directed to:

Scott.Lincoln@noaa.gov