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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).

   
010612_0 010712_0 012812_0 031912_1 050212_0 052312_0 052312_1 052412_2 052512_2 052612_0 052712_1 052812_0 060412_0 060512_2 060612_0 060812_0 060912_1 061212_1 061512_1 062812_0 063012_0 070112_0 070512_0 070912_0 071012_0 071012_2 071112_0 071212_0 071412_2 071512_0 071612_1 071812_0 071912_1 072012_1 072112_1 072412_0 072412_1 072412_2 072512_4 072712_0 072812_0 072812_3 072912_3 073012_1 073112_0 080412_1 081112_0 081212_0 081312_0 081412_0 081712_0 081812_0 081912_1 082012_0 082012_1 082112_1 082212_1 082312_1 082412_1 082512_0 082712_0 082712_2 082812_0 082812_1 082912_1 090112_0 090312_0 090412_0 090512_0 091012_0 091112_0 091112_1 091212_0 091212_5 091312_0 091412_1 091512_0 091512_2 092712_0 092812_0 101312_1 101512_0 102412_0 110512_0 111312_0 121212_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.