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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).

   
020512_0 021512_0 021612_0 022312_0 022412_0 022712_2 032312_0 032412_0 050412_0 050412_1 050812_1 050912_1 052112_1 052112_2 052112_4 052312_0 052512_0 052812_2 052912_0 052912_1 053012_3 060312_3 060512_0 060512_6 060712_0 060712_3 060812_1 060912_0 061012_1 061112_2 061712_0 061912_1 062012_1 062312_4 062512_3 062712_2 062812_3 062912_1 070212_0 070312_0 070512_0 070512_5 070612_6 070712_4 070812_2 070812_8 070912_2 071012_2 071112_0 071112_2 071412_1 071512_0 071612_0 071712_0 071812_3 071912_2 072012_3 080112_1 080312_2 080412_3 080412_4 081012_2 081212_3 081312_1 081812_0 081812_1 081912_0 082012_0 082412_3 082512_4 082612_1 082612_4 082712_1 082812_1 082912_2 090312_2 090612_1 090712_0 090812_0 090912_3 091012_1 091112_0 091212_2 091312_2 091912_0 092012_0 092112_0 092212_0 092212_4 092312_0 092312_2 092412_0 092512_0 092512_1 092612_1 100212_0 100312_1 100412_0 100512_0 100812_1 102712_0 110112_0 111512_0 111612_0 112212_0 113012_0 122212_0 122412_1

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.