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Late for 65 degree dewpoint

23 Oct 2012 05:51 AM
Very muggy air for this time of year visited Iowa on Monday. The dew point temperature reached 65 degrees Fahrenheit for Des Moines. It is very late in the year to have such a high dew point temperature as shown by the featured chart. Only two other years (1934, 2004) have experienced 65+ dewpoint after 22 October. Two more very warm days are expected before much colder air arrives and highs will only be in the 40s!

Voting:
Good: 19
Bad: 6

Tags:   2012   2004   1934  

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Arbitrary Metrics

31 Jul 2012 05:43 AM
This feature continues the series of comparing how the drought this growing season stacks up with previous years. For this metric, an estimated areal coverage of Iowa is presented that had a previous thirty day period with less than two inches of total rainfall received. This arbitrary metric attempts to show the breadth of dry continues and how it changed over the period. The top chart presents the daily coverage for this year and four previous years of note. In this comparison, 2012 shows up much worse than 1988 in late July, but better in late June. The middle chart presents the simple average of the value over the June and July period and 2012 has the highest value around 60% since the year 1900 followed closely by 1988. The bottom chart looks at this value during a key period for corn development in mid-July. 1936 is easily the largest average coverage as shown by this metric. So the question remains unresolved, how does this year compare with previous drought years? Is it worse than 1988?

Voting:
Good: 53
Bad: 14

Tags:   2012   1955   1934   1936   1988  

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Comparing Years

26 Jul 2012 05:47 AM
A common question asked this summer is how does this year compare with previous drought years, like 1988. While there is no easy nor correct answer to this question, we can certainly try different methods. The featured chart presents three time series of accumulated temperature and precipitation departures for the May through August time period. The year 2012 compares closely with 1988 at the current date of the year, but will it finish in a similar fashion? The current date precipitation departures from 1 May are some of the worst on record, so is this year worse than the epic years of 1934 or 1936? The temperature departure in the top chart has 1934 and 1936 with substantial leads over 2012. 1977 is thrown in as it was a significant drought for some in the state, is it worse than 2012? The bottom chart presents the distance from a zero temperature and precipitation departure, again there is no clear cut answer.

Voting:
Good: 76
Bad: 10

Tags:   2012   1955   1934   1936   1977