Monday set a heat index record for Jacksonville and surrounding areas. Extreme heat and humidity made it feel like 126 degrees in Saint Simons Island, Ga. In addition, a new daily record was broken at Jacksonville International Airport at 114° when the high reached 98°F and combined with a 77°F Dewpoint.
The heat index or feels like temperature ranked as the fourth highest on record for the month of August. Monday’s heat surpassed the previous record of 112 degrees set on Aug. 7, 2007.
The extreme heat set records in surrounding areas including Gainesville which tied the monthly highest heat index at 114. The previous highest August heat index was set on the first in 1986.
The combination of high temperatures and humidity is causing dangerous conditions that can cause heat-related illnesses this week. The National Weather Service has issued a variety of alerts to help alert people to this week’s week’s heat wave in and around in around Jacksonville.
This summer has been unusually hot with five days having feels like or heat index readings at or over 108 degrees. This ties 2019, which also totaled five, over the last 20 years at Jacksonville International.
Locals are accustomed to hot August temperatures but this week’s heat may be pushing the tolerance for anyone who has spent years in Florida. Highs will be at or over 95 all week long. This heat wave could bring even hotter daily maximum highs compared to last month.
July’s persistent heat ranked it as the hottest month on record for Jacksonville with a total of 10 days recording a 105 degree heat index; in contrast to 2022 which had four.
Focusing on the hottest days that trigger heat advisories at 108 degrees, up until August 7th, five have occurred this summer which is more than double the number from last year.
As of August 8, there are 45 more days until the end of summer and this week will likely bring several more days with heat advisory or heat warnings that may break the tie.
Tuesday we are under another Excessive Heat Warning until 8 p.m.
Here are what the three advisories mean:
In Georgia and Florida, 108 degrees is the benchmark for when to be cautious about heat related problems although locations farther north have lower thresholds for when heat alerts are issued.
The least extreme type of heat alert called a Heat Advisory is only issued when the heat index is predicted to reach at least 108 degrees for two or more consecutive hours.
Excessive Heat Warnings – are issued during the most extreme type of heat when readings will reach 113 or higher.