By CNN Meteorologist Mary Gilbert, CNN

(CNN) — The wildfire raging along the Grand Canyon’s North Rim became a “megafire” this week, doubling in size in just a few days and intensifying enough to create its own weather.

Hostile weather conditions including intense, dry heat and gusty winds drove the Dragon Bravo Fire’s explosive growth and erased much of the containment progress made by fire crews.

The northern Arizona fire has burned through nearly 112,000 acres since igniting on July 4 and was 8% contained as of Friday morning, according to the National Interagency Fire Center. It’s the largest fire currently burning in the lower 48 states and its footprint is about three times the size of Washington, DC.

The Dragon Bravo fire reached megafire status after crossing the 100,000-acre threshold. The blaze has more than doubled in size since Sunday, when it was around 50,000 acres, according to data from Inciweb.

That’s because bone-dry fire fuels, like brush, can go up in flames in an instant. Days of very dry air dehydrated those fuels to a level drier than kiln-dried lumber, according to a Thursday fire update.

Megafires like the Dragon Bravo Fire are rare — only about 3% of wildfires reach this scale — but they account for the majority of total acreage burned in the United States each year.

A lightning strike ignited the wildfire on Independence Day and crews initially chose to manage it as a controlled burn instead of smothering it immediately. The fire quickly grew out of control about a week after igniting and fire crews have been fighting to contain it ever since.

Crews have been able to control some sections of the blaze though they are not yet fully contained, Section Chief Craig Daugherty with Southwest Area Incident Management said in an update late Friday morning. The main areas of concern are along the fire’s northern edge and a portion in the southwest, where it is still spreading, Daugherty said.

The blaze tore through the North Rim’s historic Grand Canyon Lodge in mid-July and destroyed at least 70 other structures, including cabins and a visitor’s center.

The fire was 26% contained — its maximum level so far — this past weekend, but worsening weather conditions this week have triggered erratic fire behavior and lowered its containment level considerably.

In fact, the fire became so intense that it created its own weather.

Pyrocumulus or “fire clouds” were spotted over the Dragon Bravo Fire for at least seven days in a row, fire information officer Lisa Jennings told the Associated Press on Thursday.

Pyrocumulus clouds form over intense heat sources, like raging wildfires or volcano eruptions. They develop because the air above such intense heat is quickly and chaotically forced to rise, which cools and condenses the air’s moisture, forming clouds.

If a wildfire is hot and chaotic enough it could even fuel a pyrocumulonimbus – a “fire thunderstorm cloud” – that generates lightning, wind gusts and sometimes produces tornadoes. Additional lightning strikes from these types of clouds could set off new blazes or reignite areas crews have already smothered.

Even outside of the weather the fire creates for itself, conditions will remain challenging through at least early next week, if not beyond.

There is a slight chance of showers and thunderstorms on Friday, but any additional gusts or lightning in those storms could quickly negate what little, if any, help some rain brings.

An extreme heat warning is in effect for the Grand Canyon through Tuesday and periods of gusty winds will not relent into early next week. Frequent wind gusts of around 20 to 25 mph will occur Friday and through the weekend before gusts up to 30 mph pick up early next week.

Wildfire season in the US is also far from over, despite the calendar flip to August.

“We’re in the heart of summer, and the heart of the fire year,” the National Interagency Fire Center warned Friday.

The West will remain the major wildfire hot spot through at least September, forecasts from the center show.

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CNN Meteorologist Briana Waxman contributed to this report.