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: 200220032004200520062007200820092010201120122013201420152016201720182019202020212022202320242025

Left arrow for previous frame, right arrow for next, space to pause/play; click to open image in new tab. Date of each event is listed as "mmddhh" (2-digit month, 2-digit day, 2-digit hour for end of accumulation period).

   
010112 010212 010312 010412 010512 010612 010712 010812 010912 011012 011112 011212 011312 011412 011512 011612 011812 011912 012012 012112 012212 012312 012412 012512 012612 013112 020112 020212 020312 020412 020512 020612 020712 020812 020912 021012 021112 021212 021312 021412 021512 021612 021712 021812 021912 022012 022112 022412 022512 022612 022712 030412 030512 030612 030712 030812 030912 031012 031312 031412 031512 031612 031712 031812 031912 032012 032112 032212 032312 032412 032512 032712 032812 032912 033012 033112 040112 040212 040312 040412 040512 040612 040712 040812 040912 041012 041212 041312 041412 041712 041812 041912 042012 042112 042212 042312 042412 042512 042612 042712 042812 042912 043012 050112 050212 050312 050412 050512 050612 050712 050812 050912 051012 051112 051212 051312 051412 051512 051612 051712 051812 051912 052012 052112 052212 052312 052412 052512 052612 052712 052812 052912 053012 053112 060112 060212 060312 060412 060512 060612 060712 060812 060912 061012 061112 061212 061312 061412 061512 061612 061712 061812 061912 062012 062112 062212 062312 062412 062512 062612 062712 062812 062912 063012 070112 070212 070312 070412 070512 070612 070712 070812

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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