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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: 1981198219831984198519861987198819891990199119921993199419951996199719981999200020012002200320042005200620072008200920102011201220132014201520162017201820192020202120222023202420252026

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).

   
022012_0 022812_0 030912_0 032012_0 032012_1 032112_0 041612_0 041712_0 042012_0 042312_0 042412_0 042512_0 042712_0 042812_0 050112_0 050212_0 051112_0 051212_0 051212_1 051512_0 052012_0 052012_1 052012_2 052112_0 052112_1 052112_2 052212_0 052312_0 052412_0 052412_1 052512_0 052512_1 052512_2 052612_0 052712_0 052812_0 053112_0 060212_0 060612_0 060712_0 060912_0 061012_0 061112_0 061212_0 061312_0 061412_0 061512_0 061512_1 061512_2 061712_0 061812_0 061912_0 061912_1 061912_2 062012_0 062012_1 062012_2 062012_3 062012_4 062012_5 062012_6 062112_0 062212_0 062612_0 062712_0 062712_1 062712_2 062812_0 062812_1 070312_0 070612_1 070712_0 070712_1 070812_0 070812_1 070912_0 070912_1 070912_2 071012_0 071212_0 071212_1 071312_0 071312_1 071312_2 071412_0 071412_1 071512_0 071512_1 071612_0 071612_1 071712_0 071812_0 071912_0 071912_1 072012_0 072312_1 072312_2 072312_3 072312_4 072412_0 072412_1 072512_1 072612_0 072712_0 072712_1 072812_0 072812_1 072912_0 072912_1 073012_0 080112_0 080112_1 080212_0 080312_0 080512_1 080612_0 080612_1 080712_0 080712_1 080712_2 080712_3 080812_0 081012_0 081212_0 081212_2 081312_0 081412_0 081412_1 081512_0 081512_1 081512_2 081512_3 081512_4 082112_1 082512_0 082712_0 082812_0 082912_0 082912_1 083012_0 090412_0 090512_0 090512_1 090512_2 090612_0 090712_0 090712_1 090812_0 090912_0 090912_1 091112_0 091412_0 091512_0 091512_1 091612_0 091712_0 091812_0 091912_0 092112_0 092412_0 092612_0 092712_0 092712_1 092812_0 100512_0 100612_0 100612_1 100712_0 100712_1 100812_0 100812_1 100912_0 100912_1 101012_0 101112_0 101712_0 101912_0 102012_0 103112_0 110712_0 110812_0 110912_0 112212_0 112812_0 120512_0 121312_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.