Monday was the first official day of summer, but the mercury in many thermometers has been reaching summer temperatures all month.

According to Lyle Alexander, a meteorologist with National Weather Service’s Wakefield station, summer heat settled in a bit before the season officially started and may result in one of the hotter Junes on record.

“No area records were broken or probably will be broken, but its been consistently hotter this month,” Alexander said. “We’ll probably have one of the top 10 — if not, top five — hottest Junes on records, which date back to 1874.”

Temperatures for mid-to-late-June are normally in the mid 80s, but there already have been several days in June that have broken 90, Alexander said.

“It has been unseasonably warmer,” Alexander said. “We’re only running about five degrees higher than normal, but it’s been consistently higher.”

The heat seems to have caught some off guard, however, as there have been increased visits at local emergency rooms for heat-related symptoms.

“We had seven visits from people coming in because of heat-related symptoms,” said Sentara Belleharbour’s Clinical Manager Alisa Petrauskas. “It is certainly early for this type of weather for us.”

Of the seven cases seen, Petrauskas said, majority dealt with outdoor contractors.

“Most of them were men in their mid-20s to mid-40s and had been working outdoors,” Petrauskas said. “They have a bad habit of drinking soda and coffee, which both have caffeine. Caffeine is a diuretic, so it will dehydrate you even faster.”

Petrauskas reminds people to drink water and sports drinks — but more water than sports drinks — and periodically to take a break to cool down.

The same rules apply to children.

“Children will dehydrate faster than adults, so it’s important to monitor their water intake,” Petrauskas said.

Just as sodas and coffee aren’t a water substitute for adults, juices are not a substitute for children.

“If you need to, dilute the juice with water,” Petrauskas said.

Symptoms that your body is getting dehydrated are dizziness, nausea or a strong odor and bright yellow color in urine.