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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: 201820192020202120222023202420252026

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).

   
010112_0 010212_1 011112_0 022512_0 022612_0 022712_0 031312_1 032712_0 041312_0 050212_3 050812_1 051212_1 051312_4 051412_4 052012_5 052612_1 052612_2 052712_0 052712_1 052812_0 052912_0 053012_1 053112_0 060212_0 060312_1 060412_0 060512_0 060612_0 060912_2 061012_2 061112_1 061212_1 061312_1 061412_2 061512_3 061712_0 061712_3 061812_4 062212_1 062212_3 062312_1 062312_2 062412_3 062512_1 062612_1 062912_4 070112_1 070212_1 070312_4 070312_5 070412_5 070812_1 071012_1 071012_2 071112_3 071212_3 071512_0 071612_2 071612_4 071712_4 072012_2 072112_1 072112_2 072212_0 080112_4 080212_3 080312_1 080312_2 080412_2 080412_4 080512_2 080512_4 080612_0 080612_2 080712_3 080712_4 080912_4 080912_6 081012_0 081112_0 081212_0 082112_0 082212_0 082412_0 082512_3 082712_0 082812_0 082912_2 083012_0 083112_1 090312_1 090412_1 090512_1 090612_1 090712_0 091912_1 092212_1 092312_2 092312_3 100212_1 100312_0 100312_2 100512_0 100512_1 101412_0 102612_1 102712_1 102812_0 111612_0 111712_0 120712_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.