Past IEM Features tagged: jul14
After one of the wettest Junes on record, July was on the cool and dry side of average. The featured map displays calculated monthly precipitation totals from the automated airport weather sensors in the state. Only a few locations were above average with many others well below and even below an inch for the month. After having mostly eliminated the drought situation in the state during June, it may start creeping back in unless rain returns.
High temperatures on Sunday once again struggled in the 70s, which is a very pleasant treat for July in Iowa. This July has seen plenty of cool days which adds up to one of the coolest July's on record as highlighted by the featured chart. The average temperature (mean of daily high and low) for the month is shown along with the coolness rank over the number of available years. This unofficial ranking has the Quad Cities and Davenport on its way to the coldest July on record. It is interesting to see how much different Des Moines appears on this chart. Outside of a sensor calibration issue, the first obvious explanation is the Urban Heat Island affect that is most pronounced for that site in Iowa.
The featured map displays the coolest low temperature reported by the Iowa ASOS/AWOS sites for Tuesday and Wednesday this week. Temperatures have once again dipped into the lower 50s this Thursday morning. We can only go upwards from here and the forecast has temperatures climbing back to seasonal levels by this weekend with muggy weather returning next week. It is kind of a treat to have such cool weather during the warmest period of the year.
Much was made this previous winter about the "polar vortex" and the biblical outbreaks of cold weather it brought the eastern half of the country. Tongue-in-cheek, the vortex appears to be back next week with high temperatures forecasted to struggle in the upper 60s and 70s. The featured chart presents the average high temperature for Des Moines for the 14-19 July period. This should be about the warmest period of the year, but instead will be some 12 degrees below average.