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<br />in approximately one week. He mentioned that a cold front was moving into Colorado
<br />and residents might expect a new front about every three days for the near future, He
<br />also mentioned that there should still be a high degree of concern for fire danger across
<br />the state,
<br />
<br />Klaus Wolter. NOAA Climate Diagnostic Center. Long Term Weather Outlook
<br />1, El Nino's growth stalled again last month, leaving conditions essentially unchanged,
<br />Despite some model forecasts that reduce its strength over the next few months, I believe
<br />more growth is possible, although there is considerable uncertainty about its eventual
<br />size,
<br />
<br />2, Historically, even modest El Nino conditions have been associated with wetter than
<br />average conditions for November in Colorado and several adjacent states, The jury is still
<br />out on August rainfall, but I am not very optimistic that we will see above average totals
<br />in much of the state, This cautions against being overly optimistic with regard to
<br />beneficial El Nino impacts during this fall,
<br />
<br />3, The new experimental forecast for October through December precipitation shows a
<br />better than 50/50 chance for wetness in eastern Colorado, compared to continued
<br />uncertainty over the mountains and western Colorado, Further south, New Mexico looks
<br />may end up on the dry side for the fall, while Arizona's odds are only marginally shifted
<br />towards wetness, These forecasts are based on a variety of influences on our climate, with
<br />El Nino being just one of several indicators used here, The one factor that continues to
<br />handicap this forecast is the historic tendency of drought to perpetuate themselves, For
<br />instance, during this spring and early summer season, my forecast for relatively wet
<br />conditions in the Northern Front Range vs,relatively dry conditions from the Four
<br />Comers southwestward verified on the dry side for everybody,
<br />
<br />4, A week-long monsoonal interlude in early August brought some beneficial moisture to
<br />Colorado as well as south of here, but was too short-lived to turn this monsoon season
<br />around, Vigorous cold fronts out of Canada have cooled down the eastern plains, without
<br />bringing much moisture, The monsoon season is not over yet, and some forecast models
<br />reestablish it by the middle of next week.
<br />
<br />5, Bottomline: Given the extraordinary lack of moisture in Colorado over the last four
<br />months, we have now reached drought conditions of truly historic proportions, Although
<br />the monsoon may still deliver some good-sized rain events, the window of opportunity is
<br />closing, For the rest of the year, the historic odds for moisture in Colorado are at least
<br />even, More importantly, they are higher than last year at this time, Nevertheless, the
<br />moisture deficit has gotten so big now that even a wet fall (and winter) will not be
<br />sufficient to refill the reservoirs, A "miracle" spring like the one in 1995, in addition to a
<br />wet fall AND winter, could do it, but I put the odds for that below 10%, In fact, given the
<br />historic tendency for El Nino winters to enhance moisture over the southern rather than
<br />the northern mountains of Colorado, I am very concerned about a deepened snow drought
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