Colorado State University
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: 201820192020202120222023202420252026

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).

   
25010318 25011912 25012712 25020212 25020218 25020300 25020500 25020506 25020706 25021312 25021318 25021400 25021500 25021506 25021606 25022000 25022512 25022600 25030218 25030300 25030406 25030700 25030706 25030712 25030718 25030800 25030806 25030812 25030818 25030900 25031206 25031300 25031312 25031318 25031400 25031406 25031412 25031418 25031500 25031506 25031512 25031518 25031600 25031606 25031612 25031618 25031700 25031706 25031900 25031906 25031912 25031918 25032000 25032400 25032406 25032700 25032712 25032718 25032800 25032806 25032818 25032900 25032906 25033000 25033018 25033100 25033106 25040100 25040206 25040300 25040312 25040406 25040412 25040418 25040500 25040506 25040512 25040600 25040606 25040612 25040700 25040706 25040900 25041506 25041706 25041800 25042000 25042006 25042112 25042118 25042200 25042300 25042306 25042318 25042400 25042406 25042412 25042418 25042500 25042506 25042600 25042606 25042612 25042618 25042700 25042718 25042806 25042812 25043000 25043006 25043012 25043018 25050100 25050200 25050206 25050212 25050300 25050306 25050406 25050500 25050506 25050600 25050606 25050700 25050706 25050712 25050900 25050906 25051000 25051100 25051106 25051118 25051200 25051206 25051212 25051218 25051300 25051306 25051318 25051400 25051406 25051500 25051506 25051512 25051518 25051618 25051700 25051706 25051712 25051806 25051812 25051900 25051906 25051912 25052000 25052006 25052106 25052200 25052218 25052306 25052412 25052500 25052506 25052512 25052518 25052600 25052606 25052612 25052700 25052706 25052800 25052806 25052900 25052906 25053000 25053006 25053012 25053100 25060100 25060200 25060206 25060300 25060306 25060312 25060318 25060400 25060406 25060412 25060500 25060512 25060600 25060606 25060612 25060618 25060700 25060706 25060712 25060806 25060812 25060818 25060900 25060906 25060912 25061000 25061006 25061012 25061100 25061106 25061112 25061200 25061206 25061212 25061218 25061300 25061306 25061312 25061318 25061400 25061406 25061412 25061500 25061506 25061512 25061518 25061600 25061606 25061612 25061618 25061700 25061706 25061712 25061718 25061800 25061806 25061818 25061900 25061912 25062000 25062006 25062018 25062106 25062112 25062118 25062212 25062218 25062300 25062306 25062312 25062400 25062406 25062412 25062418 25062500 25062506 25062512 25062600 25062606 25062612 25062700 25062706 25062712 25062800 25062806 25062818 25062900 25062906 25062912 25062918 25063000 25063006 25063012 25070100 25070106 25070112 25070200 25070206 25070212 25070218 25070300 25070306 25070312 25070318 25070400 25070406 25070412 25070418 25070500 25070506 25070512 25070518 25070600 25070606 25070612 25070618 25070700 25070706 25070712 25070718 25070800 25070806 25070906 25070912 25070918 25071000 25071006 25071012 25071018 25071100 25071106 25071200 25071206 25071212 25071218 25071300 25071306 25071312 25071318 25071400 25071406 25071412 25071418 25071500 25071506 25071512 25071518 25071600 25071606 25071612 25071618 25071700 25071706 25071712 25071718 25071800 25071806 25071818 25071900 25071906 25071912 25071918 25072000 25072006 25072012 25072100 25072106 25072112 25072118 25072200 25072206 25072212 25072218 25072300 25072306 25072312 25072318 25072400 25072406 25072412 25072500 25072506 25072512 25072518 25072600 25072606 25072612 25072618 25072700 25072706 25072712 25072718 25072800 25072806 25072812 25072818 25072900 25072906 25072912 25072918 25073000 25073006 25073012 25073018 25073100 25073106 25073112 25073118 25080100 25080106 25080112 25080118 25080200 25080206 25080212 25080300 25080306 25080312 25080318 25080400 25080406 25080418 25080500 25080506 25080512 25080518 25080600 25080606 25080618 25080700 25080712 25080718 25080800 25080806 25080812 25080900 25080906 25080912 25080918 25081000 25081006 25081012 25081018 25081100 25081106 25081112 25081118 25081200 25081206 25081212 25081218 25081300 25081306 25081312 25081318 25081400 25081406 25081412 25081500 25081506 25081512 25081518 25081600 25081606 25081612 25081700 25081706 25081712 25081800 25081806 25081812 25081818 25081900 25081906 25081912 25081918 25082000 25082012 25082100 25082106 25082200 25082206 25082212 25082300 25082306 25082312 25082318 25082400 25082406 25082412 25082500 25082506 25082518 25082600 25082606 25082612 25082618 25082700 25082706 25082712 25082718 25082800 25082806 25082812 25082818 25082900 25082906 25082912 25082918 25083000 25083006 25083018 25083100 25083106 25083112 25083118 25090100 25090106 25090112 25090206 25090218 25090300 25090306 25090318 25090400 25090412 25090418 25090500 25090506 25090512 25090600 25090606 25090612 25090700 25090706 25090712 25090800 25090806 25090812 25090818 25090900 25090906 25090918 25091000 25091006 25091100 25091106 25091112 25091118 25091200 25091206 25091212 25091218 25091300 25091306 25091312 25091318 25091400 25091406 25091412 25091418 25091500 25091506 25091512 25091600 25091606 25091618 25091700 25091706 25091712 25091718 25091800 25091806 25091818 25091900 25091906 25091912 25091918 25092000 25092018 25092100 25092106 25092112 25092200 25092206 25092212 25092218 25092300 25092306 25092312 25092318 25092400 25092406 25092412 25092418 25092500 25092506 25092512 25092600 25092606 25092700 25092712 25092718 25092800 25092806 25092900 25092906 25093000 25093006 25100112 25100300 25100312 25100318 25100418 25100500 25100506 25100512 25100600 25100612 25100706 25100718 25100800 25100806 25100812 25100900 25101006 25101018 25101100 25101106 25101118 25101200 25101206 25101212 25101218 25101300 25101400 25101406 25101412 25101418 25101606 25101612 25101700 25101900 25102018 25102100 25102218 25102406 25102506 25102612 25102618 25102700 25102706 25103112 25110118 25110512 25110612 25111400 25111406 25111518 25111600 25111606 25111612 25111700 25111706 25111718 25111806 25111900 25112018 25112306 25112312 25112606 25120900 25120906 25120918 25121012 25121100 25121106 25121118 25121518 25121706 25121712 25121718 25121818 25121900 25121906 25121912 25122118 25122200 25122206 25122212 25122418 25122500 25122506 25122512 25122606 25122906 25122912 25123100
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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