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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).

   
031112_0 041612_1 041712_4 041812_1 041912_0 042612_0 050212_0 050312_1 050812_0 050912_1 051112_1 051812_0 052412_1 052712_4 052812_2 052912_2 053112_0 060312_0 061612_0 061612_2 061712_1 061712_2 062012_1 062412_0 062812_0 062912_0 063012_5 070212_1 070312_2 071212_2 071212_3 071312_2 071412_1 071712_0 072612_1 072912_4 073012_1 073112_3 080112_1 080112_2 080212_3 080212_4 080312_0 080312_1 080412_0 080412_1 080412_2 080512_0 080512_1 080612_0 080712_1 080712_3 080812_0 080812_1 080812_2 080912_0 080912_2 081012_2 081212_2 081212_3 081312_1 081312_2 081312_5 081412_0 081412_1 081512_0 081512_3 081612_0 081712_0 082012_0 082012_3 082112_0 082112_3 082212_0 082312_0 082512_0 082612_0 082612_2 082712_0 083012_0 083112_2 090112_0 090112_2 090212_0 090212_2 090312_0 090312_1 090412_0 090412_1 090812_0 090912_0 090912_3 091012_3 091712_1 092112_1 092212_1 092312_1 092312_3 092412_2 092712_0 092812_0 093012_1 100112_1 100512_0 100712_0 100712_1 100912_0 101012_1 101712_0 102312_0 110612_2 110712_1 121212_0 121712_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.