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. 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).

   
011912_1 012012_0 012012_1 012112_0 012112_1 012212_1 012212_2 012312_0 012612_0 020412_0 022312_0 022312_1 022412_0 022912_0 031312_0 031512_0 031612_0 031612_1 031812_0 031812_1 031912_0 032112_0 032112_1 032212_0 032212_2 032312_0 040112_0 040412_0 041212_0 041512_0 041612_0 041712_0 042712_0 042712_2 042812_0 042812_1 043012_0 043012_1 050112_0 050212_1 050312_0 050412_0 050512_0 050512_2 050612_0 050812_0 051112_0 051212_0 051512_0 051612_0 052012_0 052512_0 052812_1 052812_2 052812_3 052912_0 052912_1 053012_0 053012_1 053112_0 060412_0 060612_0 060712_0 060712_1 060712_2 060812_0 060812_1 060812_2 061012_0 061112_0 061212_0 061412_0 061512_1 061612_0 061612_1 061612_2 061712_0 061712_1 061712_2 061912_0 061912_1 062012_0 062012_1 062112_0 062112_1 062412_0 062512_0 062512_1 062512_2 062612_0 062612_1 062712_0 062712_1 070112_0 070212_0 070312_0 070412_1 070512_0 070612_0 070612_2 070612_3 070712_0 070712_2 070712_3 070812_0 070812_1 070912_0 070912_1 071012_0 071012_2 071012_4 071112_0 071112_1 071112_2 071112_3 071212_0 071212_1 071212_2 071312_0 071312_1 071512_0 071612_0 071612_1 071812_0 071912_0 071912_1 072012_1 072112_0 072112_1 072212_0 072212_2 072312_0 072412_1 072412_2 072512_0 072512_1 072512_2 072512_3 072612_1 072612_2 072812_1 072912_0 072912_1 073012_0 073112_0 073112_1 080112_0 080112_1 080412_0 080612_0 080612_1 080712_1 080812_0 080912_0 081012_0 081112_0 081112_1 081712_1 081712_2 081812_0 081912_0 082012_0 082312_0 082312_1 082412_3 082512_2 082512_3 082612_0 082612_2 082712_0 082712_1 082712_2 082812_0 083012_0 083112_0 090112_0 090212_0 090212_1 090312_1 090412_0 090412_1 090412_2 090512_0 090512_1 090512_2 090512_3 090512_4 090612_2 090712_0 090712_1 090812_0 090912_0 091212_1 091812_0 091912_0 091912_1 091912_2 092612_0 092712_0 092712_1 092712_2 092712_3 092812_2 092912_0 093012_0 093012_1 093012_2 100112_0 100212_0 101212_0 101512_0 102312_0 102412_0 102512_0 102912_0 103012_0 103112_0 103112_1 112112_0 112212_0 113012_0 120112_0 120112_1 120212_0 120212_2 120312_1 120312_2 120512_0 120612_0 121212_0
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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