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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).

   
011012_0 011112_0 011212_0 011912_0 021312_0 032912_1 042212_0 042612_0 051212_0 051312_1 060312_0 060312_3 060312_4 060412_2 060412_7 060512_2 060512_3 060912_5 060912_8 061012_5 061112_1 061112_2 061112_3 061212_2 061312_1 061412_5 061712_0 062312_1 062412_0 062912_1 062912_3 063012_1 063012_3 070112_2 070112_3 070212_1 070412_0 070512_0 070712_2 070812_1 071012_1 071712_4 071912_0 072112_1 072112_3 072912_0 073012_1 073112_3 080312_1 080412_2 080512_1 080512_4 081012_1 081112_1 081312_1 081512_0 081612_0 081712_0 081912_1 082212_0 082412_1 082412_3 082712_0 082812_1 083012_0 083112_0 090112_0 090212_0 090412_0 090512_1 090712_1 090812_1 090912_0 091012_3 091712_3 092712_0 093012_0 100212_0 100612_2 100712_0 100812_0 100912_1 101012_0 101112_1 101212_2 101312_3 101512_0 101512_1 110812_0 111612_0 120212_0 123112_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.