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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).

   
012112_0 012212_0 012312_0 012412_0 041712_0 041812_0 042412_1 050312_1 050412_1 051212_0 051212_1 051312_1 051312_3 052112_0 052612_1 052712_1 060512_4 060612_0 060712_0 061012_0 061112_0 061212_1 061212_3 061412_2 061412_3 061512_1 061612_2 061812_5 061912_5 062212_1 062712_0 062912_1 070112_2 070212_3 070312_1 070412_0 070512_0 070512_1 070612_1 070712_0 070812_2 070812_3 070812_4 070912_0 071112_0 071412_1 072012_2 072112_2 072212_3 072312_0 072312_1 072312_2 072412_0 072412_3 072512_0 072612_0 072612_2 072712_0 072812_1 072912_0 072912_1 073012_2 073112_1 080112_1 080212_0 080212_1 080312_0 080312_1 080412_0 080412_1 080412_4 080512_3 081012_0 081112_1 081212_2 081312_0 081412_2 081512_0 081612_1 081712_0 081912_4 082012_2 082112_4 082212_0 082212_1 082312_2 082412_2 082412_3 082512_3 082812_2 083012_1 090912_0 092312_0 092412_0 092412_1 092512_1 092812_1 092912_1 093012_1 100112_1 100212_0 100712_0 101512_0 102612_1 121512_0 122012_0 122112_0 122212_0 122312_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.