Climate change boosts unusual October heat across the U.S

October 13, 2026

Unusually high October temperatures are forecast across a broad swath of the U.S. this week, bringing hot and humid conditions to parts of the Texas Gulf Coast and near-record warmth farther east. 

The heat will affect communities recovering from Hurricane Isaias in the Florida Panhandle and southern Alabama, where widespread power outages have disrupted access to air conditioning and storm cleanup efforts are ongoing. These conditions could increase the potential for heat-related illness, particularly among those without power and people working outdoors to clear debris and repair storm damage.

How unusual is the forecasted heat?

Unusually warm October temperatures are forecast across the U.S. from October 12-16, as a strong ridge of high pressure extends from the Gulf Coast northward through the Mississippi Valley and into the Midwest. Daily high temperature records could be tied or broken across portions of the Lower Mississippi River Valley, Mid-South, and Southeast through Thursday, with record highs in parts of Illinois early in the week.

• Southern Texas and the Lower Mississippi Valley: Highs of 90-97°F (32–36°C) are forecast across eastern and southern Texas, Louisiana, Mississippi, eastern Arkansas, and western Alabama. These temperatures will run 7-22°F (4-12°C) above normal across Texas, Louisiana, and western Mississippi, with the largest departures from normal across Arkansas and northern Mississippi. Along the Texas Gulf Coast, wet-bulb temperatures will reach 77-79°F (25-26°C), levels considered dangerous because of the risk of heat-related illness.

• Midwest and Ohio Valley: Highs of 91-97°F (33–36°C) are forecast across Missouri, Illinois, western Tennessee, and Indiana, and parts of Kentucky later this week. Temperatures will generally be 14-22°F (8-12°C) above normal, with some areas of eastern Missouri and central Illinois forecast to reach 27-29°F (15-16°C) above normal

• Southeast: Highs of 85-90°F (29-32°C) are forecast across the Florida Panhandle, southern and eastern Alabama, Georgia, the Carolinas, and some portions of Virginia. Temperatures will be 6-20°F (3-11°C) above normal, with the largest departures across northern portions of the region later this week.

How has climate change influenced this heat?

• Climate Shift Index (CSI) levels of 5 — the highest possible — are forecast in San Antonio, Houston, and Miami, meaning human-caused climate change made this extreme heat at least five times more likely. This signals an exceptional climate-influenced event.

• From October 12-16, more than 85 million people from the Gulf Coast northward through the Mississippi Valley and into parts of the Midwest will experience at least one day with average temperatures reaching a CSI 3 or higher, indicating an exceptional influence from climate change.

• Approximately 25.5 million people across Texas, Oklahoma, Arkansas, and Louisiana are forecast to experience dangerous humid heat that would not have occurred without climate change.

To request an interview with a Climate Central scientist, please contact Abbie Veitch at aveitch@climatecentral.org. 

How do we know climate change is influencing this heat?

The Climate Shift Index uses peer-reviewed methodology and real-time data to estimate how climate change has increased the likelihood of a particular daily temperature.