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: 2002200320042005200620072008200920102011201220132014201520162017201820192020202120222023202420252026

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).

   
012112_0 012812_0 012912_0 020812_0 021312_0 021412_0 021512_0 021712_1 022412_0 030112_0 031312_0 031312_1 031412_0 031412_2 031512_0 031512_1 031712_0 031812_0 032112_0 032212_0 032512_0 032612_0 032812_0 032912_0 042512_0 042812_0 042812_1 042912_0 042912_1 042912_3 050112_0 050312_0 050412_0 050412_2 050512_0 051112_0 051212_0 051212_1 051512_0 051612_0 051612_1 051712_0 051712_1 051812_0 051812_1 051812_2 051912_0 051912_2 052012_0 052112_1 052112_2 052112_3 052312_1 052312_2 052412_1 052412_2 052412_3 052412_4 052512_0 052512_1 052512_3 052612_0 052612_1 052712_0 052712_1 053112_0 060112_1 060212_0 060412_0 060412_1 060412_2 060512_1 060512_2 060812_0 060812_1 060812_3 060912_0 060912_1 060912_2 060912_3 060912_4 060912_5 061012_0 061012_2 061012_4 061112_0 061112_1 061112_2 061112_5 061212_0 061212_1 061212_2 061312_0 061412_0 061512_0 061512_1 061512_2 061912_0 062012_0 062012_1 062112_1 062212_0 062212_1 062512_1 062512_2 062512_3 062612_0 062612_1 062612_2 062712_0 062712_2 062812_0 062812_1 062812_2 062912_0 062912_1 063012_0 063012_1 063012_3 070112_0 070112_3 070212_0 070212_1 070212_2 070312_0 070412_0 070412_1 070512_0 070512_2 070612_0 070612_1 070712_0 070712_1 070712_2 070712_3 070712_4 070812_0 070812_1 070912_0 070912_2 071012_0 071012_1 071012_3 071012_4 071112_0 071212_0 071212_1 071212_2 071312_0 071312_1 071312_2 071312_3 071312_4 071412_1 071412_3 071512_0 071512_3 071612_0 071612_1 071612_2 071612_4 071612_6 071712_2 071712_3 071712_5 071712_6 071812_0 071812_2 071812_3 071812_4 071912_1 071912_2 071912_3 071912_4 072012_1 072112_0 072212_1 072312_0 072312_1 072312_3 072412_0 072412_1 072412_2 072512_0 072512_1 072512_2 072512_6 072512_7 072612_0 072612_1 072612_3 072612_4 072612_5 072612_6 072712_1 072712_3 072812_0 073012_1 073012_2 073112_2 080112_1 080212_0 080212_1 080312_0 080312_1 080312_3 080412_0 080412_1 080412_2 080412_3 080412_4 080512_0 080512_1 080512_2 080512_3 080612_0 080812_0 080812_1 080812_2 080812_3 080912_1 081112_0 081112_1 081112_2 081212_0 081212_1 081312_0 081312_1 081312_2 081312_3 081312_4 081412_0 081412_1 081412_4 081512_0 081612_0 081612_1 081612_2 081712_1 081712_2 081812_0 081812_1 081912_0 081912_1 081912_2 082012_1 082012_2 082012_3 082012_4 082112_1 082112_2 082112_3 082112_4 082112_5 082212_0 082212_1 082312_0 082312_2 082312_3 082412_0 082412_2 082412_3 082512_0 082612_1 082612_2 082712_1 082712_2 082812_0 082812_1 082912_1 083012_0 083112_0 083112_1 090112_0 090112_3 090112_5 090212_0 090212_1 090212_2 090312_1 090312_2 090412_0 090412_1 090412_2 090512_0 090512_1 090612_0 091112_0 091412_0 091512_0 091612_0 091612_1 091912_0 092012_0 092012_1 092112_0 092212_0 092312_0 092312_1 092412_1 093012_1 093012_3 100112_0 100112_1 100112_2 100112_3 100112_4 100212_0 100212_1 100212_2 100312_0 100312_1 100412_1 100412_2 100512_0 100612_0 100612_1 100712_0 100812_0 100912_0 100912_1 100912_2 100912_3 101012_0 101012_4 101112_0 101312_0 101412_0 101412_1 101512_0 102212_0 102512_0 102512_1 102512_3 102612_0 102612_1 102712_0 102712_1 103012_1 111212_0 111412_0 121012_0 121112_0 121412_0 121412_1 121512_0 121512_1 121812_0 122412_0 122512_0 122612_0 122612_1 123112_0 123112_1
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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