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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: 20182019202020212022202320242025

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).

   
25010312 25010412 25010512 25010912 25011012 25011112 25011312 25011412 25011512 25012112 25012212 25012312 25012412 25020312 25020412 25020512 25021212 25021312 25021412 25021512 25021912 25022012 25030412 25030712 25030812 25030912 25031012 25031112 25031412 25031512 25031612 25031712 25031812 25031912 25032012 25032112 25032212 25032812 25032912 25033012 25033112 25040412 25040512 25040612 25041712 25041812 25041912 25042612 25042712 25042812 25050112 25050212 25050512 25050612 25050712 25050812 25051212 25051512 25051612 25051712 25051812 25052012 25052112 25052512 25052612 25052712 25052812 25052912 25060312 25060412 25060512 25060612 25060712 25060812 25061212 25061312 25061412 25061512 25061612 25061712 25061812 25061912 25062012 25062312 25062412 25062512 25062612 25062712 25062812 25062912 25063012 25070112 25070312 25070412 25070512 25070612 25070712 25070812 25070912 25071112 25071212 25071312 25071512 25071612 25071712 25071812 25071912 25072012 25072112 25072212 25072312 25072412 25072512 25072712 25072812 25072912 25073012 25073112 25080112 25080212 25080312 25080412 25080512 25080612 25080712 25080812 25081012 25081112 25081212 25081412 25081612 25081712 25081812 25081912 25082212 25082312 25082412 25082612 25082712 25082812 25082912 25083012 25090512 25090612 25090712 25090812 25090912 25091012 25091112 25091212 25091312 25091412 25091512 25091712 25091812 25091912 25092412 25092512 25092612 25092812 25092912 25093012 25100612 25100712 25101112 25101212 25101312 25101412 25101512 25101612 25102112 25102212 25102312 25102712 25102812 25102912 25110112 25110212
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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