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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).

   
010212_0 030212_0 043012_0 050612_0 051312_0 051412_1 051712_3 052412_0 052512_1 052512_2 053112_0 053112_1 060212_1 060412_2 060612_0 060712_1 060812_1 061312_1 061412_0 061912_0 062312_0 062512_2 062712_0 062812_0 070212_1 070312_0 070412_4 070612_2 070712_2 070812_2 070912_4 071312_1 071812_1 072312_4 072312_5 072412_5 072612_0 072612_1 072712_3 072812_0 072812_1 072912_0 072912_2 073012_0 073112_0 080112_0 080212_0 080312_3 080412_0 080512_0 080512_4 080612_2 080612_6 080712_3 080712_5 080812_0 080812_2 081212_0 081412_0 081512_3 081612_0 081812_4 081912_0 082012_0 082012_4 082112_0 082212_0 082312_0 082512_2 082612_6 082712_0 082712_2 090512_0 090612_2 090712_0 091212_3 091312_0 091412_0 091512_1 092312_0 092712_0 092912_0 093012_0 100212_2 101612_0 101712_0 110612_0 120512_0 122812_3

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.