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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: 201820192020202120222023202420252026

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).

   
020712_0 040312_0 040612_0 040712_0 041812_0 042112_0 042712_4 042812_0 042812_3 042912_2 050412_2 050412_3 050912_0 050912_1 051212_0 052212_1 052712_2 053012_0 053112_0 060212_1 060212_2 060512_4 061112_0 061212_1 061312_0 061412_0 061612_1 061712_1 061812_0 061912_0 061912_3 062012_1 062212_0 062212_1 062312_0 062312_1 062412_0 062912_2 063012_0 070212_0 070812_1 071112_2 071112_3 071212_4 071312_6 071612_2 071812_3 071812_7 072012_1 072212_1 072312_1 072412_2 080112_8 080112_9 080612_0 080712_0 080812_0 080912_1 081012_1 081012_2 081112_2 081112_3 081212_0 081212_2 081312_0 081412_0 081512_1 081512_5 081612_2 082012_2 082212_1 082312_0 082312_1 082412_0 082912_0 083012_0 090212_2 090412_0 091512_0 091712_2 091812_2 091812_5 091912_0 091912_5 092212_6 092612_0 092712_0 092812_0 092912_0 093012_1 101012_0 102012_0 102112_0 110512_0 110612_0 110712_0 110812_0 110912_0 110912_3 112312_0 122812_0 122912_2

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.