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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).

   
020412_0 020412_1 020512_0 032812_0 032912_0 040512_1 040612_0 042712_0 050212_0 050712_0 051212_1 051512_0 051512_1 051612_1 051712_0 052612_0 060312_2 060412_5 061312_4 061412_5 061412_8 061612_5 061712_1 061812_3 061912_4 062012_1 062512_0 062612_0 062712_0 062912_3 063012_2 070112_2 070312_1 070412_0 070412_1 070512_0 070612_0 070712_0 070712_1 070712_3 070812_3 071512_2 071812_1 071912_5 072112_0 072212_1 072212_3 072312_0 072312_6 072412_1 072712_1 072812_0 072912_1 072912_3 073012_0 073012_1 073112_2 080112_0 080312_1 080312_5 080312_8 080412_5 080512_2 080812_4 081012_4 081212_5 081612_3 081812_5 081912_2 082312_1 082612_1 082712_1 082812_1 082912_5 090612_0 090912_2 091212_5 091412_2 091512_4 091712_1 092412_1 092412_4 092512_3 092912_2 101212_3 101312_1 101312_2 101412_1 101612_1 102812_0 121112_0 122012_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.