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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: 20182019202020212022202320242025

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).

   
012812_0 032812_1 051512_0 051612_1 051612_2 051712_1 051812_0 051812_1 052012_2 052412_0 052512_2 052712_1 053012_0 053112_0 060112_1 060812_2 060912_0 060912_6 061012_0 061112_2 061112_4 061112_5 061212_0 061312_0 061412_3 061912_2 062012_0 062212_1 062512_2 062612_0 062612_1 062712_0 062812_0 062812_1 062912_0 063012_3 070112_3 070212_0 070312_4 070412_2 071012_3 071212_1 071412_3 071512_5 071612_5 071712_0 071712_3 071812_0 071812_4 071912_3 072312_0 072412_0 072512_1 072512_4 072612_0 072612_1 073012_0 073112_0 080112_0 080512_1 080812_6 080912_3 081112_0 081212_0 081212_3 081312_3 081512_4 081712_1 081812_1 081812_3 081912_1 082012_3 082012_5 082112_0 082112_1 082212_3 082212_5 082312_0 082312_1 082412_0 082812_1 082912_0 082912_3 083012_0 083112_4 090112_2 090212_1 090412_1 092112_1 093012_2 100412_0 100512_0 100712_0 100812_0 101312_0 102512_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.