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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).

   
010912_0 021112_0 022412_0 031912_0 053112_0 060312_0 060512_2 060612_3 061112_1 061112_2 061112_3 061212_1 061312_1 061412_2 061512_0 061612_1 061612_4 062012_4 062212_0 062412_2 062512_2 062812_3 070312_2 070412_1 070512_0 070612_0 070712_0 070812_0 070812_2 071112_2 071312_2 071512_0 072012_2 072612_1 080512_1 080912_1 081912_1 082012_1 082512_0 082812_0 082912_0 082912_1 083012_0 083112_0 090112_0 090212_1 090312_0 090812_1 090912_0 090912_1 091012_0 091112_0 091112_1 091212_2 091312_1 091612_3 092212_0 092312_2 092712_0 100412_0 101612_0 102712_0 111012_0 111012_1 111112_0 121612_0 121712_0 121712_1 122912_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.