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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).

   
032312_0 050412_0 051712_3 051812_3 052012_2 052412_0 052512_0 052512_2 052912_0 053012_0 053112_1 060212_4 060312_3 060712_0 060912_2 061012_1 061212_1 061312_1 061812_5 061912_4 061912_5 062012_2 062112_0 062112_1 062212_0 062212_2 062512_0 062512_4 062612_0 062712_1 062712_2 062812_0 062912_3 063012_3 070112_5 070312_1 070312_2 070412_1 070412_3 070512_2 071012_0 071612_1 071812_0 072012_1 072412_0 072612_0 080112_1 080712_1 081012_2 081512_3 081612_2 081712_3 081812_2 081812_4 082112_0 082112_5 082212_3 082312_0 082412_0 082612_0 082912_1 090312_2 090312_4 090412_3 090512_5 090612_5 090712_0 090812_0 090912_3 091012_2 091112_1 091212_1 091612_1 091712_1 091812_0 092312_0 092412_0 092612_0 100212_0 100312_0 101012_0 101612_0 120312_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.