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Monitoring of heavy precipitation events

These images show locations where average recurrence intervals for precipitation have been exceeded. These are referred to, for example, as "100-year rainstorms", though this terminology can cause confusion, so a more accurate description is "less than a 1% probability of occurring at a given location in any given year." This is an automated search for the types of events discussed in Schumacher and Johnson (2005, 2006) and Stevenson and Schumacher (2014), using gridded precipitation analyses, as well as updated to use NOAA's Atlas 14 to define the average recurrence intervals. (In the northwest US, Atlas 14 has not yet been updated, so older Atlas 2 information is used.) Archived images from past events when the thresholds have been exceed are shown below.

Each dataset has been regridded to a 4-km latitude-longitude grid (the same grid used by the PRISM Climate Group) prior to calculating the exceedance points. This allows for a closer "apples-to-apples" comparison between precipitation datasets. The archive of past events is actively under development; if you don't yet see images for a particular dataset/duration, check back soon! Recent data (within the last several months) has not undergone quality control, so use recent maps with caution.


Select dataset: Stage IVMRMSPRISM      Current maps  Interactive maps of past events
Select average recurrence interval: 10-year100-year1000-year
Select duration: 72-hour48-hour24-hour6-hour
Select year: 20022003200420052006200720082009201020112012201320142015201620172018201920202021202220232024

Left arrow for previous frame, right arrow for next, space to pause/play; click to open image in new tab. Date of each event is listed as "mmddhh" (2-digit month, 2-digit day, 2-digit hour for end of accumulation period).

   
051812 051912 052112 052712 052812 052912 053012 060112 061512 062112 062212 062312 062512 062612 062712 071512 071612 071712 071912 072012 072512 072612 072712 072812 080112 080212 080412 080512 080612 080712 080812 080912 082312 082412 082812 082912 090812 090912 091112 091212 091312 091412 091512 091612 091712 092012 092112 100412 100612 100712 101212 101412 101512 112512

This material is based upon work supported by the National Science Foundation under Grant No. AGS-2337380. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.



DISCLAIMER: The images and data on this site are intended for meteorological education and research purposes and, although they should generally be up to date, are not monitored at all times. Do not use for making decisions where money or lives are at stake. For official forecasts and warnings, visit the National Weather Service.