The mercury reached the century mark two other times — July 2, 1966 and July 5, 1999. In fact, the average daily temperature climbs from 72 degrees at the start of the month to 75 by July 31. The warmest July on record happened 17 years ago, in 1994, with an average temperature of 78.4 degrees.
Last July was one of the hottest on record. You may recall the heat wave over the Independence Day holiday weekend. The high temperatures from July 4 through July 7 were 97, 93, 98, and 95 degrees, respectively. In fact, record high temperatures were established July 6 and 7. The mercury also reached 95 degrees July 24. The average temperature for the month was 78 degrees, just shy of the all-time record.
Many people have asked me why the hottest time of the year happens over a month after the first day of Summer. Well, it takes the Earth awhile to absorb the heat. As the Sun’s angle gets higher in the sky and the days grow longer in May and June, the Northern Hemisphere slowly starts to warm.
It’s much like warming your home. When you turn your thermostat up to 72 degrees after being away all day in the Winter, it will take awhile for the house to warm up. It doesn’t happen instantly. That’s why our hottest days are typically in July and early August.
On the flip side, the coolest temperature ever recorded in these parts in July was 49 degrees on July 1, 1988. Aside from that, every record low for the month is in the 50s. Believe it or not, according to the National Weather Service record book, a trace of snow fell at the airport on July 4, 1950. I find that too hard to believe.
As far as precipitation is concerned, the wettest July on record happened in 1971 when over a foot of rain (12.84″) fell. The average monthly rainfall is 3.77 inches. There have been several memorable rainstorms in July. For example, nearly a half-foot (5.95″) of rain fell on July 19, 1971, and nearly four inches (3.93″) was recorded on July 29, 1990. Two other days delivered well over three inches of rain — July 30, 1960 (3.57″) and July 23, 1953 (3.45″).
The length of daylight decreases next month. For example, on July 1, the Sun rises at 5:23 and sets at 8:30. By the middle of the month, on July 15, the Sun rises at 5:32 and sets at 8:24. However, at the end of the month, it rises at 5:47 and sets at 8:10, meaning we lose 44 minutes of daylight. Remember, the “longest” day of the year happened at the Summer Solstice in late June.
Our weather will begin to heat up over the holiday weekend with daytime highs in the 80s to close to 90 degrees inland by Sunday afternoon. A threat of a few scattered showers or a thunderstorm will be with us Sunday, but most of the three-day weekend should be fine.
Paul
