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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: 1981198219831984198519861987198819891990199119921993199419951996199719981999200020012002200320042005200620072008200920102011201220132014201520162017201820192020202120222023202420252026

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).

   
031012_0 041712_2 041712_3 041912_0 042612_0 050712_2 050812_0 050912_1 051312_0 052412_0 052512_1 052612_3 052912_1 053012_1 060312_0 061512_0 061612_0 061612_2 061712_1 061812_1 061912_1 062812_0 063012_4 070112_0 070212_0 070312_3 070412_2 070812_0 071112_2 071212_4 071212_5 071712_0 072612_0 072912_5 080112_0 080112_3 080112_4 080212_2 080212_3 080312_4 080412_0 080412_1 080712_0 080712_4 080812_0 080812_1 080812_2 080912_2 081112_2 081112_3 081212_2 081212_3 081312_0 081312_1 081312_3 081412_0 081412_1 081412_2 081412_3 081512_0 081612_0 081712_1 081912_0 082012_0 082012_4 082112_0 082112_5 082212_0 082312_1 082412_2 082512_0 082512_1 082512_2 082612_1 083012_0 083012_1 090112_0 090112_2 090212_0 090212_1 090212_2 090312_0 090312_1 090812_0 090812_1 092012_0 092112_0 092212_3 092312_2 092312_3 092412_0 092712_0 092912_0 093012_1 100112_1 100712_1 100812_0 100912_1 101012_1 102212_0 102912_0 110512_1 110612_1 121212_0 121312_0 121612_2 121712_1

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.