Temperatures averaged slightly above normal. Measurable rain fell on 3 days, totaling 0.09 inch. August is normally the driest month of the year, averaging 0.24 inch.
Precipitation for June, July, and August totaled only .14 inch, making this the second driest summer on record at the airport.
A massive upper level high pressure ridge covering the west kept the first week of August hot. Temperatures at Boise topped out at 100 on the 5th and 101 on the 6th.
Southerly flow aloft brought enough monsoon moisture for light showers on the 2nd and again on the 8th, plus enough cloud cover on the 8th to prevent the temperature from reaching 90.
On the 9th and 10th, a low pressure trough which had resided off the West coast since late July moved inland. As the associated cold front interacted with the monsoon moisture, it triggered thunderstorms which produced light but measurable precipitation and gusty outflow winds. A gust of 40 mph was measured at the airport on
The 9th.
With a high of only 78, the 11th was the coolest day of the month, thanks to the north Pacific air which accompanied the trough.
Following the trough, highs were back in the 90s from the 13th through the 15th, and dry westerly flow aloft blocked monsoon moisture from invading southwest Idaho.
On the 16th and 17th, a weak cold front trailing south from a low pressure system over Canada lowered temperatures a few degrees.
The high pressure ridge expanded north again, and highs were in the 90s from the 18th through the 21st.
On the 22nd and 23rd, a Pacific cold front, followed by an upper Level low pressure trough from the the Gulf of Alaska, brought a trace of rain and kept highs from exceeding the 80s. A dry cold front followed on the 25th, keeping temperatures below normal through the 26th.
A warming trend commenced on the 27th as the high pressure ridge rebuilt and persisted through the end of the month, with temperatures around 10 degrees above normal.
