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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).

   
010112_0 010312_0 011012_0 022512_0 041312_0 050812_2 051112_1 051212_1 051312_4 051812_0 051912_2 052412_4 052512_2 052612_0 052612_3 052712_0 052712_2 052812_0 052912_0 060112_0 060212_2 060312_1 060312_4 060812_2 060912_0 061012_0 061112_0 061212_2 061312_0 061712_0 062112_4 062212_1 062312_2 062412_0 062512_1 062812_4 063012_0 070212_3 070312_1 070812_5 071012_0 071112_3 071212_1 071412_2 071412_3 071412_5 071612_3 072112_2 072212_1 072512_2 072812_0 073112_4 080112_1 080212_2 080312_2 080312_4 080312_5 080412_0 080412_2 080512_1 080512_2 080512_3 080512_7 080612_2 080812_4 080912_1 081012_0 081212_2 082112_0 082412_2 082512_0 082612_0 082812_0 082912_0 083112_0 090212_1 090312_1 090612_1 090712_1 091812_1 092112_0 092212_1 092212_2 100312_0 100512_1 101212_0 102512_1 102812_0 111612_0 111712_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.