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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).

   
010312_0 020712_2 021112_0 031312_0 051512_0 051712_0 051812_0 051912_0 052012_1 052112_3 052312_0 052412_1 052512_0 052512_4 052612_0 060912_2 061012_1 061112_1 061212_1 061512_0 061712_1 062012_3 062012_5 062112_0 062112_1 062312_1 062712_0 062812_3 062912_5 063012_2 063012_3 063012_4 063012_5 070112_5 070712_0 070812_0 070812_1 070812_2 071012_0 071512_1 071512_2 072112_0 072112_1 072512_0 072512_2 072612_0 072712_1 072712_2 072812_0 072912_0 073112_0 080212_1 080312_0 080412_0 080512_0 081412_0 081412_1 081512_0 081512_1 081612_0 082512_0 082612_0 082612_1 082912_2 083012_0 090112_1 090112_2 090912_0 090912_2 091012_1 091112_1 091412_1 091712_0 091812_0 102612_0 102912_0 111312_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.