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Real-Time Weather Data
Precip. Sys. Research Group
Colorado State University
Real-Time Weather Data
Precip. Sys. Research Group
Colorado State University
Real-Time Weather Data
Precipitation Systems Research Group
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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: 200220032004200520062007200820092010201120122013201420152016201720182019202020212022202320242025

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).

   
25020312 25020412 25030212 25030312 25030712 25032812 25032912 25040412 25040512 25040612 25042612 25042712 25042912 25050612 25050712 25051212 25051312 25051512 25051612 25060312 25060412 25060512 25061112 25061212 25061312 25061412 25061512 25061812 25062312 25062412 25062512 25062612 25062712 25062812 25062912 25070312 25070412 25070512 25070612 25070712 25070812 25070912 25071012 25071512 25071612 25071712 25071812 25072112 25072212 25072512 25072712 25072812 25072912 25073012 25073112 25080112 25080212 25080312 25080412 25080612 25080712 25080812 25080912 25081012 25081112 25081712 25081812 25082312 25082412 25082712 25082812 25082912 25090612 25090912 25091012 25091412 25091512 25092612 25092912 25100512 25101112 25101312 25101412 25102712 25102812
on the left is a map showing locations where rainfall exceeding an average recurrence interval threshold occurred, and on the right is the corresponding precipitation analysis for that time period

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.

Walter Scott, Jr.
College of Engineering
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