June's 5 Weather Changes: Hurricane Season's Start To Tornadoes, Rising Highs And A Gloomy Spot

Yahoo

4 days ago

The swing from spring to summer is what June is known for, and with that comes some weather changes as the atmosphere reacts to increasing warmth just like we do by modifying our clothing selections.
While hurricane season's start comes to mind first when talking about June, there are four other changes we also watch for in the month:
Big Picture: June 1 marks the start of the six-month-long hurricane season, though it's usually a slower month compared to August, September and early October. The southeastern U.S. coast, the Gulf and the northwestern Caribbean Sea are typical breeding grounds for tropical storms in June. Since that's close to land, it increases the chance of impacts along the Gulf and Southeast coasts of the U.S. when a storm forms.
Deeper Dive: On average in the Atlantic Basin, one named storm forms every one to two years in June and a hurricane develops about once every five years. Recent Junes have proven to be more active, with two named storms forming in four of the last five Junes. Continental U.S. hurricane landfalls in the month are rare with only four since 1950 and the last one in 1986 (Bonnie), however tropical storms have proven to be impactful numerous times.
(MORE: June - Hurricane Season's Opening Act)
Big Picture: Tornadoes can happen just about anywhere in the Lower 48 this month, given the widespread warmth and humidity. However, the area at greater risk of tornadoes in June stretches from the Plains into the upper Midwest and Great Lakes. In the Southeast, June tornadoes tend to be fewer compared to earlier in spring since the jet stream shifts to the north.
Deeper Dive: June tallied up an average of 186 tornadoes each year between 2004 and 2023, the 3rd most of any month behind only May and April. It's not just about tornadoes, as peak hail activity also occurs in June, especially in the Plains, according to some studies. Not only that, but damaging wind gusts are also common, sometimes occurring in what's called a derecho, which contributes to the widespread destruction of trees, power lines and sometimes structures.
Big Picture: Drenching thunderstorms and June, as well as the rest of summer, go hand-in-hand. Heavy rainfall rates of an inch per hour or more can rapidly trigger flash flooding anywhere from the South to the Midwest and Northeast. Not only that, more of us are outside this time of year, which increases the odds of lightning being a danger for activities like going to the beach or participating in sports.
Deeper Dive: More water vapor can exist in warmer air this time of year, which increases the rainfall potential for both individual thunderstorms and larger-scale complexes of storms in many parts of the country. Not only that, the jet stream slows and moves north, which causes storms to move slower, increasing their rainfall potential. And of course, the early part of hurricane season can introduce the possibility of flooding from tropical storms.
(MORE: 5 Reasons Its The Most Dangerous Time For Flash Flooding)
Big Picture: Temperatures continue to rise toward their July peak in much of the U.S., which means the chance of multiday heat waves increases. Average highs are in the 70s and 80s for much of the Northeast and Midwest regions. 80s and 90s are commonplace in summer's first month across the South, as well as plenty of humidity. Geography plays a big role in the West, with average highs ranging from the 60s and 70s in higher elevations and the Pacific Northwest to the 90s and 100s in the Desert Southwest.
Deeper Dive: Average highs in the month jump considerably from start to finish, as these examples illustrate: New York City: 75 degrees June 1 → 84 degrees June 30 | Chicago: 76 degrees June 1 → 84 degrees June 30 | Dallas: 89 degrees June 1 → 94 degrees on June 30 | Denver: 78 degrees June 1 → 88 degrees June 30 | Phoenix: 100 degrees June 1 → 107 degrees on June 30
Big Picture: It's not all sunshine, storms and heat everywhere in the U.S. during June. Coastal California is prone to what's called "June gloom", which is a mixture of fog and low clouds that often make an appearance in the morning. These clouds often clear by early afternoon as heating from the sun arrives, but sometimes they can be stubborn to leave and last deep into the day, especially at beaches.
Deeper Dive: Known as the marine layer, its formation is driven by cold, more humid air coming from the chilly ocean waters that can be pushed onshore due to a pressure difference between high pressure off the California coast and a thermal low-pressure system that develops inland due to intense heating. Low clouds form and are pushed inland into places like Los Angeles and San Diego. Sometimes the low clouds can be deep enough to produce drizzle or light rain showers.
Chris Dolce has been a senior digital meteorologist with weather.com for nearly 15 years after beginning his career with The Weather Channel in the early 2000s.