The Kurdish fighters had not slept. They held their guns and kept watch from the sandbag berm they'd built. They could not afford to lose focus. The enemy, they knew, would likely use the bad weather to their advantage.
Part of the United States-led coalition, the Kurds have fought ISIS on the ground for months
. Ayn al Issa is vital. The terrorists depend on its main road to transport supplies. The Kurds have won and lost and won the area in the past. They know that to take it fully, they must be relentless.
"We are waiting all the time, we are ready for them," the unit's commander said. He wanted to be called Rubar, but would not, for his own security's sake, give his last name or age to CNN.
In a brief interview conducted over the phone with U.S.-based reporters, the commander recounted what happened.
When the first pop of gunfire from ISIS fighters came, it was clear the militants had used the cover of the fog to rush the Kurds, to shoot at them within a few yards. The fighting was so close, ISIS fighters dove behind trenches the Kurds had constructed.
At one point, a coalition airplane roared overhead, but had to hold fire because of the risk of killing Kurds, Rubar said.
How long could a close fight like this last? 20 minutes? 45 minutes? Time is hard to measure when you're fighting for your life. Rubar said it felt like three hours.
None of his fighters died, he said. And he was weary, but proud to say they killed at least a dozen ISIS fighters. Some managed to escape, disappearing into the fog.
The Kurds did the work of every battle's end with ISIS. They stretched the enemy's corpses' on the ground and, carefully, removed their shirts to make sure none were wearing suicide belts. Then they quickly buried them. For the Kurds, even an enemy who bastardizes a beloved religion, who kills your family and friends and threatens your country, gets to be buried.
Hours after the fight, Rubar doesn't say he is exhausted. His ragged voice does that for him.
Rubar told CNN that his soldiers don't have adequate supplies and weapons. He worries about that. But he's going to keep fighting. His unit plans to head into Raqqa.
He said he's unafraid. He knows he could die.
"I know that it's a big possibility," he said. "It's a choice I make. I am ready for death and I accept it."