National weather data released on Monday found July was the hottest month on record for the contiguous United States.The National Oceanic and Atmospheric Administration found the average temperature across the Lower 48 states was 76.9 degrees in July, approximately 3 degrees higher than the 20th-century average, according to National Centers for Environmental Information data dating back to 1895. The month surpasses July 1936 and July 2012 to become the warmest July and warmest month overall.Above-average temperatures stretched across the contiguous U.S., with every state recording temperatures ranking in the warmest third of their July temperature records. Thirteen states experienced one of their five warmest Julys on record.
Wyoming recorded its hottest July and hottest month ever recorded, with its average temperature 5.1 degrees above normal and nearly a degree warmer than its previous record set in July 2007.The record-breaking month came as several heat domes settled over portions of the country. A heat dome occurs when a persistent area of high pressure traps hot air over a region, allowing temperatures to build over several days.A heat dome engulfed Washington, D.C., and areas along the East Coast and in the Midwest over the July Fourth holiday, and temperatures reached near 100 degrees with the heat index rising to 112 in some areas. Another strong ridge of high pressure settled over the northern Rockies in mid-July, bringing record-breaking temperatures to parts of Montana, Utah, and Wyoming.On the opposite end of the spectrum was Alaska — although not part of the contiguous U.S., the state recorded its coldest July since 2008.THE AMERICA 250 PATRIOT GAMES ARE HAPPENING: WHERE TO WATCH AND MOREDespite the widespread heat, precipitation across the Lower 48 was below average. The country received an average of 2.55 inches of precipitation, 0.23 inches below normal, placing July in the driest third of the 132-year record.Moving into August, NCEI predicts temperatures will again be above average across central and southern America. Additionally, the agency said portions of California and the southern Plains have a greater than 50% likelihood of seeing above-average temperatures.
