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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).

   
011212_0 011712_0 020712_0 020812_1 020812_2 020912_0 021312_0 030612_0 031312_0 031412_0 031512_1 032112_0 032112_1 040912_0 041012_0 041112_0 042012_0 042112_0 042612_0 050912_0 051612_0 051612_2 051712_0 051712_1 051812_1 051912_0 052012_0 052012_1 052012_2 052012_3 052112_0 052112_1 052112_2 052212_1 052312_3 052412_0 052412_1 052412_2 052412_3 052512_0 052512_2 052612_0 052612_1 052612_2 052712_0 052712_1 052812_0 053012_0 053112_0 060512_0 060712_0 060812_0 060912_0 060912_1 060912_2 060912_3 060912_4 061012_0 061012_1 061012_3 061112_1 061212_0 061412_1 061512_0 061712_1 061812_1 061812_2 062012_0 062012_1 062012_2 062112_1 062112_3 062112_4 062112_5 062212_0 062212_2 062212_3 062212_4 062312_0 062312_1 062412_0 062412_1 062512_1 062612_1 062812_0 062812_1 062812_3 062912_0 062912_2 063012_0 063012_2 063012_4 063012_5 070112_1 070112_2 070112_3 070112_5 070212_0 070212_1 070212_2 070312_0 070312_1 070312_2 070512_0 070512_1 070512_2 070612_0 070712_0 070712_1 070712_2 070712_3 070812_0 070812_1 070812_2 070912_1 070912_3 070912_4 071112_0 071112_1 071212_0 071412_1 071512_0 071512_2 071512_3 071612_0 071612_1 071612_2 071612_3 071712_0 071912_1 071912_2 072012_1 072112_0 072112_1 072212_1 072212_2 072312_2 072412_1 072512_0 072512_1 072512_3 072612_1 072612_2 072612_3 072612_4 072712_0 072712_1 072712_3 072812_0 072812_1 072812_3 072812_5 072812_6 072912_2 073012_0 073012_1 073112_0 073112_1 080112_0 080112_2 080212_0 080412_0 080412_1 080512_0 080612_0 080612_1 080712_0 080912_0 081012_1 081112_0 081112_1 081312_0 081412_1 081512_0 081512_3 081512_5 081612_0 081612_3 081712_0 081712_1 081712_2 081812_0 081812_1 082212_0 082212_1 082412_0 082512_0 082512_1 082712_0 082812_0 082812_3 082912_0 082912_1 082912_2 082912_3 083012_0 083012_1 083112_0 090112_1 090112_2 090212_0 090212_1 090212_2 090312_1 090412_0 090512_0 090512_1 090812_0 090812_1 090812_2 091012_1 091012_2 091012_3 091112_0 091112_2 091112_3 091212_1 091412_0 091412_1 091412_2 091512_0 091612_0 091712_0 091812_0 091912_0 092212_1 092312_0 092412_1 092512_0 100312_0 100412_0 101012_0 101112_0 101212_1 101212_2 101512_0 102212_0 102312_1 102412_0 102512_0 102912_0 110812_1 110912_0 111012_0 111212_0 111212_1 111312_0 111312_1 111412_1 122612_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.