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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 IVMRMSPRISMCONUS404CoCoRaHS      Current maps  Interactive maps of past events
Select average recurrence interval: 10-year100-year1000-year
Select duration: 72-hour48-hour24-hour6-hour
Select year: 198119821983198419851986198719881989199019911992199319941995199619971998199920002001200220032004200520062007200820092010201120122013201420152016201720182019202020212022

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).

   
010912_0 020812_0 020812_1 021312_0 022312_0 022412_0 031612_0 032012_0 032312_0 032812_0 032812_1 033012_0 033012_1 033112_0 041312_0 041412_0 042012_0 042112_0 042312_0 042312_1 042312_2 042612_0 042712_0 042812_0 042812_1 042812_2 042912_0 042912_1 043012_0 043012_1 050112_0 050212_0 050212_1 050212_2 050312_0 050912_0 051012_0 051012_1 051112_0 051112_1 051112_2 051212_0 051312_0 051312_1 051412_0 051612_0 051612_1 051712_0 052112_0 052112_1 052212_0 052312_0 052812_0 052912_0 053012_0 053112_0 053112_1 060212_0 060412_0 060412_1 060412_2 060512_0 060512_1 060612_0 060712_0 060912_0 061012_0 061112_0 061112_1 061112_2 061212_0 061212_1 061612_0 061812_0 061912_0 061912_1 061912_2 062012_0 062212_0 062412_0 062512_0 062512_1 062612_0 062612_1 062612_2 062712_0 062712_1 062712_2 062712_3 062812_0 062812_1 062812_2 062912_0 063012_0 070112_0 070212_0 070212_1 070312_0 070512_0 070512_1 070612_0 070612_1 070612_2 070612_3 070712_0 070712_1 071312_0 071512_0 071612_0 071612_1 071612_2 071712_0 071712_1 072012_0 072012_1 072112_0 072112_1 072212_0 072212_1 072212_2 072212_3 072312_0 072312_1 072312_2 072312_3 072312_4 072412_0 072412_1 072412_2 072412_3 072412_4 072412_5 072512_0 072512_1 072512_2 072512_3 072612_0 072612_1 072612_2 072612_3 072612_4 072712_0 072712_1 072712_2 072712_3 072712_4 072712_5 072812_0 072812_1 072912_0 072912_1 072912_2 073012_0 073012_1 073012_2 073012_3 073112_0 080112_0 080212_0 080212_1 080312_0 080312_1 080312_2 080312_3 080312_4 080412_0 080412_1 080512_0 080512_1 080612_0 080712_0 080712_1 080812_0 080812_1 080812_2 080912_0 080912_1 081012_0 081012_1 081112_0 081112_1 081112_2 081212_0 081312_0 081412_0 081412_1 081512_0 081512_1 081612_0 081612_1 081612_2 081712_0 081712_1 081712_2 081712_3 081812_0 081812_1 081912_0 081912_1 082012_0 082012_1 082112_0 082112_1 082112_2 082112_3 082112_4 082212_0 082312_0 082412_0 082512_0 082512_1 082512_2 082612_0 082612_1 082612_2 082712_0 082812_0 082812_1 083012_0 083112_0 083112_1 090112_0 090212_0 090212_1 090312_0 090312_1 090412_0 090412_1 090512_0 090512_1 090612_0 090612_1 090612_2 090712_0 090712_1 090912_0 090912_1 090912_2 090912_3 091012_0 091112_0 091112_1 091112_2 091212_0 091212_1 091312_0 091312_1 091312_2 091412_0 091412_1 091412_2 091512_0 091512_1 091612_0 091712_0 091812_0 091912_0 091912_1 091912_2 091912_3 091912_4 092012_0 092112_0 092112_1 092312_0 092312_1 092412_0 092412_1 092412_2 092712_0 092812_0 092912_0 092912_1 093012_0 100112_0 100212_0 100312_0 100412_0 100712_0 100812_0 100912_0 100912_1 101012_0 101212_0 101312_0 101412_0 101412_1 101512_0 101512_1 101712_0 101812_0 101912_0 101912_1 101912_2 102012_0 102112_0 102112_1 102212_0 102212_1 102312_0 102712_0 102812_0 102812_1 103012_0 103012_1 103012_2 103112_0 103112_1 110212_0 110212_1 110212_2 110312_0 110412_0 110512_0 110512_1 111112_0 111212_0 111912_0 112012_0 112112_0 112212_0 112212_1 112512_0 112512_1 112512_2 112512_3 112612_0 112612_1 113012_0 120312_0 121312_0 121412_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.