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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 25020512 25020712 25021412 25021512 25021612 25021712 25021812 25021912 25022012 25022112 25022212 25030212 25030312 25030412 25030712 25030812 25030912 25031512 25031612 25031712 25031812 25032812 25032912 25033012 25033112 25040112 25040212 25040312 25040412 25040512 25040612 25040712 25040812 25040912 25041912 25042012 25042112 25042212 25042312 25042412 25042512 25042612 25042712 25042812 25042912 25043012 25050112 25050212 25050412 25050612 25050712 25050812 25050912 25051212 25051312 25051412 25051512 25051612 25051712 25051812 25051912 25052012 25052112 25052512 25052612 25052712 25052812 25052912 25053012 25060212 25060312 25060412 25060512 25060612 25060712 25060812 25060912 25061012 25061112 25061212 25061312 25061412 25061512 25061612 25061712 25061812 25061912 25062012 25062112 25062212 25062312 25062412 25062512 25062612 25062712 25062812 25062912 25063012 25070112 25070212 25070312 25070412 25070512 25070612 25070712 25070812 25070912 25071012 25071112 25071212 25071312 25071412 25071512 25071612 25071712 25071812 25071912 25072012 25072112 25072212 25072312 25072412 25072512 25072612 25072712 25072812 25072912 25073012 25073112 25080112 25080212 25080312 25080412 25080512 25080612 25080712 25080812 25080912 25081012 25081112 25081212 25081312 25081412 25081512 25081612 25081712 25081812 25081912 25082012 25082112 25082212 25082312 25082412 25082512 25082612 25082712 25082812 25082912 25083012 25083112 25090112 25090212 25090312 25090412 25090512 25090612 25090712 25090812 25090912 25091012 25091112 25091212 25091312 25091412 25091512 25091612 25091712 25091812 25091912 25092012 25092112 25092212 25092312 25092412 25092512 25092612 25092712 25092812 25092912 25093012 25100112 25100412 25100512 25100612 25100712 25100812 25100912 25101012 25101112 25101212 25101312 25101412 25101512 25101612 25101712 25101812 25102412 25102512 25102612 25102712 25102812 25102912 25111512 25111612 25111712 25111812 25112012 25112112 25112212 25112312 25120712
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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