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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 IVMRMSPRISMCONUS404CoCoRaHS      Current maps  Interactive maps of past events
Select average recurrence interval: 10-year100-year1000-year
Select duration: 72-hour48-hour24-hour6-hour
Select year: 198119821983198419851986198719881989199019911992199319941995199619971998199920002001200220032004200520062007200820092010201120122013201420152016201720182019202020212022

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).

   
010412_0 021812_0 040412_0 040512_1 040612_1 042412_0 042412_1 042512_1 042512_2 051012_0 051412_1 051512_1 052412_1 053112_3 060112_2 060912_1 061012_1 061012_4 061212_3 061312_2 061412_0 061512_0 061612_0 061712_0 061812_3 061812_4 061912_2 062012_0 062712_0 062912_2 063012_0 070112_0 070312_2 070412_0 070412_2 070612_6 070712_3 070812_0 071412_2 071512_0 071512_2 071512_3 071612_1 071712_3 072512_0 072612_0 072712_0 072812_0 072812_1 080112_1 080312_0 080412_0 080512_7 080612_3 080612_5 080712_2 081312_0 081412_3 081512_1 081612_0 081612_2 081912_1 082012_1 082112_2 082212_0 082212_1 082612_1 082612_2 082812_1 082912_0 083012_2 083112_0 090112_1 090212_0 090212_1 090312_1 090612_0 090712_0 090812_1 090912_1 091012_1 091712_0 091812_0 091912_0 092012_1 092212_1 092312_2 092712_2 092812_1 092912_2 093012_1 101012_0 102112_1 102212_0 102812_2 110412_1 110912_0 112612_0 120912_2 121012_0 123012_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.