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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 IVMRMSPRISMCONUS404CoCoRaHS      Current maps  Interactive maps of past events
Select average recurrence interval: 10-year100-year1000-year
Select duration: 72-hour48-hour24-hour6-hour
Select year: 198119821983198419851986198719881989199019911992199319941995199619971998199920002001200220032004200520062007200820092010201120122013201420152016201720182019202020212022

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).

   
041712_0 050312_0 050412_0 050612_0 051812_1 051812_4 051912_0 051912_3 052012_0 052012_3 052012_4 052412_1 052612_0 052612_1 052712_0 052812_2 052912_1 053012_1 053112_1 060212_1 060612_0 060712_1 061312_0 061412_0 061612_0 061612_1 062012_0 062112_0 062112_2 062212_0 062612_0 062812_0 063012_1 070212_1 070212_2 070412_1 070512_0 070712_0 070812_2 070912_0 071012_1 071112_1 071212_3 071512_1 071612_1 071712_0 071712_1 071812_0 071912_2 072112_0 072212_0 072912_0 073012_0 080412_0 080412_2 080812_2 080912_0 081512_0 081712_0 082512_0 082612_0 082712_1 082812_0 082912_2 083012_0 090112_0 090112_1 090212_3 090612_0 090812_0 090912_0 091012_0 091112_0 091212_0 091312_0 091412_2 091912_0 092012_0 092112_0 092612_1 093012_1 100412_0 101012_0 101412_0 103112_0 120212_1 122212_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.