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there precipitation totals come from April. May. and June. So it is opposite from mountains to plains. These individual stations cast of the mountains share the dry \\inter phenomena. The Ilea\'y Rain Probabilities graphic shows that the chances arc best for hea\')' rains in May with a drop otTto the lowest point at the Fourth of July. lie warned that there arc no absolutes with climate but that this is the general trend in Colorado. Interpreting this graph he explained that during the middle and late May there is good chances for hea\)' rains. During the July 4lh period there is a remarkable lull. One exception was the July 3.4 frijole Creek storm event that was 16 inches of rain in not much time. Then you see an interesting return to last ten days of July that is the ()nset of the monsoon and last hurrahs of the winter. There is a second lull in end of august and then the third peak. September through October is southwest dominated for precipitation and April and t\1ay is plains dominated for precipitation. Once its warmer the air holds more water vapor. ~1ax 1 hour precipitation versus elevation now has a data set for a 45. year period. Ilere we arc looking at max one-hour rainfall. For a big summer thunderstonn, the higher you go in elevation the lower your max rainfall is expected to be. but there arc some outliers even at high altitudes. Nolan showed the NOAA precipitation frequency atlas that has the I OO.year 24 hour precipitation values or what is called the nlOO-year storm" for 24 hour durations. This was last updated from 1973 using data from late 1 960s precipitation and precipitation since 1970 has not been incorporated. The largest values arc in southeast Colorado. 6.5 inches. Whereas the Front Range is 5 inches from Golden to I.oveland and is slightly decreasing to the cast. I.arry I.ang pointcd out that Utah and others had updated thcir ~O^A Atlas with new maps for their states and they had more definition to their lines but the avcrage numbers didn't go up or do\\ n that much. Nolan asked about ho\\ many places experiencc 1 OO-ycar storm on average? Thc ans\\cr is about 150 places in Colorado have I OO.year storms in different locations per year. Nolan sho\\ed the drought monitor map from ~Ia) 31 that had (mly small portions of northeast and northern cast plains in drought. There is an emcrging drought in Oklahoma and southwest Kansas. Nolan stated that the history of the month of ~Iay for the last 6--8 )ears is a drier trend. .6. . . . . . . . . . tEA"" IWN fI'IIIlC8A8lUTlll ,.rlH~ttOI..IW~~CQ.OIW)O _~_~I'(M)O a a > .. L . . ___~......u._1f"0C"f_ Max. l-hour Precipitation V$. Elevation /.....~...., II w . - . . - -......-.. ~..-. - ---.-. .~ . _(llO_._>PUl)O.U,fIOII~ o 1 2 3 4 5 Mumu-nl-t'ou"P\~1 . U.S, Drought Monitor .""? i.1~ ,0:.. .t- .( '",-- ...Y'... [\ '-.", '>c., l> . 1IIIo;!.~!.:.~ - .""_:0. "'--- ...-- - ."-'- ..-- . . - ..- ..-.-- L-':: !:::o." (i)~ ...---.-.-- ---- ..--- ._-- --_&- ---..-.- --- Floo.l PrOCt'rt1Oll . Walel Prc,<<t PLlnnmg and Fuwnct' . Strum .uld l..1h- PlOIet,:llOn WalNSuppl'l Pmtt'rtJOn. COl'l!.('l"uuon PLlnnon,.