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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).

   
020612_0 040512_0 040612_0 041012_0 041712_0 041912_0 042712_5 042812_0 042812_2 050212_2 050712_1 050812_1 050912_0 051112_0 052112_1 052212_1 052612_1 053012_0 060212_1 060212_3 060412_5 061112_0 061312_0 061412_0 061512_1 061612_1 061712_0 061812_2 061912_0 061912_5 062012_1 062112_0 062112_1 062212_0 062212_1 062312_0 063012_0 070112_0 070312_0 070412_2 070712_1 070812_2 071012_2 071112_2 071212_3 071512_1 071612_3 071812_0 071912_0 072212_1 073012_8 073112_6 080612_0 080712_0 080812_4 080912_1 081012_1 081012_3 081112_2 081212_0 081312_0 081312_3 081412_1 081512_1 081512_5 082012_2 082212_1 082312_0 082312_1 090112_0 090212_2 090412_0 091512_0 091712_1 091712_3 091712_6 091812_6 091912_1 092612_0 092712_0 092812_0 092912_1 101012_0 102012_0 110512_0 110712_0 110812_0 110912_1 112212_0 112312_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.