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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: 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).

   
040512_0 041012_0 041612_2 041712_0 041912_0 042812_0 050212_0 050212_2 050212_3 050712_2 050812_2 050912_0 051012_1 052012_0 052112_1 053012_0 060212_2 060312_4 061012_0 061312_0 061512_0 061612_3 061712_0 061812_1 061912_0 061912_2 062012_1 062112_0 062112_1 062212_0 062212_1 062612_1 062912_0 063012_0 070112_1 070212_1 070712_1 071012_0 071112_0 071612_1 071612_2 071712_1 071812_1 071812_3 072012_3 073012_6 073012_7 080512_0 080612_0 080912_1 080912_2 081212_0 081312_1 081412_3 081512_2 081912_1 082012_1 082212_0 090312_0 091612_5 091712_0 091712_5 092612_0 092712_0 092812_0 101012_0 110412_0 110512_0 110712_0 110812_1 112212_0 112312_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.