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).

   
25020500 25021400 25030700 25030712 25030718 25030800 25030806 25030812 25030818 25030900 25031406 25031412 25031418 25031506 25031512 25031518 25031600 25031606 25031618 25031900 25031906 25031912 25031918 25032000 25032400 25033018 25040100 25040406 25040506 25042406 25042600 25042606 25042612 25042618 25042806 25050406 25050900 25051500 25051506 25052412 25052706 25052806 25060300 25060306 25060400 25060406 25060600 25060606 25060700 25060906 25061100 25061106 25061206 25061318 25061406 25061506 25061606 25061700 25061706 25061806 25061900 25061912 25062112 25062212 25062306 25062400 25062406 25062500 25062512 25062600 25062606 25062806 25062906 25062912 25070306 25070312 25070412 25070500 25070506 25070512 25070612 25070618 25070700 25070706 25071000 25071300 25071406 25071500 25071506 25071512 25071606 25071700 25071706 25071806 25071906 25071912 25071918 25072000 25072006 25072100 25072106 25072112 25072200 25072206 25072300 25072400 25072506 25072512 25072606 25072706 25072712 25072800 25072806 25072900 25072906 25072912 25073000 25073006 25073100 25073106 25080100 25080106 25080112 25080118 25080200 25080206 25080306 25080312 25080400 25080500 25080506 25080600 25080606 25080700 25080806 25080812 25081006 25081100 25081106 25081112 25081206 25081600 25081606 25081712 25081800 25082106 25082206 25082500 25082506 25082518 25082600 25082606 25082618 25082700 25082718 25082800 25082806 25082900 25082912 25083000 25083018 25090100 25090106 25090500 25090512 25090612 25090712 25090800 25090806 25090818 25091000 25091006 25091118 25091200 25091206 25091306 25091312 25091318 25091418 25091500 25091700 25091706 25091800 25091900 25091906 25091918 25092200 25092206 25092212 25092218 25092700 25092718 25092900 25092906 25093000 25100312 25100318 25100718 25101018 25101106 25101118 25101212 25101218 25101300 25102100 25102700 25102706 25110612 25111706 25111806 25120906 25121712 25121906 25121912 25122118 25122418 25122506 25122606
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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