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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 states of Washington and Oregon, Atlas 14 has not yet been updated, so no points are shown.) Archived images from past events when the thresholds have been exceeded 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 (e.g., within the current year) has not undergone quality control, so use recent maps with caution.


Select dataset: Stage IVMRMSPRISMCONUS404      Current maps  Interactive maps of past events
Select average recurrence interval: 10-year100-year1000-year
Select duration: 72-hour48-hour24-hour6-hour
Select year: 198119821983198419851986198719881989199019911992199319941995199619971998199920002001200220032004200520062007200820092010201120122013201420152016201720182019202020212022202320242025

Left arrow for previous frame, right arrow for next, space to pause/play; click to open image in new tab. Each event is listed as "mmddhh_e" (2-digit month, 2-digit day, 2-digit hour for end of accumulation period, one digit for the event number on this date).

   
010812_2 010912_1 010912_2 021812_0 032812_0 042712_0 043012_0 050212_0 050312_0 050412_0 050912_0 051612_1 052012_0 052112_0 052212_0 052412_4 052712_0 052912_1 052912_2 060312_1 060412_0 060412_2 060712_1 061112_1 061212_1 061212_4 061612_5 061712_4 061812_0 061812_1 061812_2 061812_3 061912_2 061912_3 062012_0 062012_1 062112_0 062112_2 062712_4 062812_2 062912_2 070512_5 071412_3 071512_1 072412_1 072612_0 073112_1 073112_2 080112_2 080312_1 080912_1 081612_2 081712_1 081912_2 082012_2 082212_2 082212_3 082412_1 082912_1 083012_1 083012_2 083012_6 083112_1 083112_3 090312_0 090612_1 091112_5 091112_6 091212_1 091212_3 091312_2 091312_5 091412_1 091512_0 091612_1 091712_0 091812_0 091912_0 092012_2 092212_0 092312_2 092512_1 092712_0 100612_0 100912_0 101512_2 111312_0

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.