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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).

   
020612_1 032312_0 042412_1 051312_0 051812_1 051912_1 051912_2 052012_4 052412_2 052812_2 052912_1 052912_3 053012_1 053012_4 053112_3 061012_0 061212_0 061712_0 061812_4 061912_3 061912_4 062012_0 062012_1 062012_4 062112_0 062112_1 062212_1 062312_0 062612_0 062612_1 062612_2 062712_0 063012_1 070612_2 071112_0 071212_0 071312_0 071312_1 071412_0 071412_1 071412_2 071712_2 072012_2 072112_0 072212_1 072512_1 072612_1 073112_0 080112_1 080112_2 080212_1 080312_0 081012_2 081212_0 081312_0 081412_0 081712_4 081712_6 081712_7 081812_2 082012_2 082112_1 082212_0 082312_0 082312_1 090312_1 090412_1 090512_0 090612_3 090712_0 090812_0 090812_2 090912_1 091012_1 091112_1 091512_1 091612_1 091712_1 091812_0 091912_0 092012_1 092112_0 092112_3 092212_0 092312_0 092712_3 100212_0 100312_0 100312_1 100412_3 100812_0 100912_1 101512_2 120312_0 122812_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.