If completed, this story will be weird (natch), long, and very non-canon. There will be minor character death, wonky science, and did I mention the weirdness?
Mindful of their footing and watchful of the above bank, Jack and Carter waded across the growing river. He grimaced as the cold, stone-gray water sloshed and slapped against his thighs. Just when he thought he was already completely soaked through...
The arroyo walls suddenly looked much more daunting than they had earlier, when the day had been dry if not exactly sunny. Jack shifted his P-90 to his back, glanced over his shoulder to make sure Carter hadn't fallen behind, and grabbed for the nearest handhold. It seemed steady, and he gave himself a good pull, kicked around for a toehold, pulled again...
Half-blinded by the rainwater bouncing off the rock and into his eyes, Jack reached the top and levered himself onto the surface. There was more tree cover here, less rain and more shadows, but no one seemed to be lurking in any of them. Jack turned around and looked down at Carter, halfway up the slope and doing fine, when something suddenly crashed.
She started, almost lost her handhold and regained it at the last second, clinging to the treacherously slick surface as they both looked in the direction of the sound. It was hard to see anything, but the noise had come from upstream, towards the mountains.
Carter gave a shout of alarm that even the wind couldn't muffle. Jack looked down, and saw it too.
The water was rising. Quickly.
The dammed-up water in the hills was finally coming down to join the party. Carter had already pulled herself a good six feet out of the river, but already a hungry current was lapping at her boots.
"Come on!" Jack called, inching as close as he dared to the incline and stretching out a hand. She was out of reach, but it gave her a goal; she set her jaw, grabbed a nub of rock, and pulled herself back out of the water. A few feet further and he was finally able to grasp her cold hand and help her up the rest of the way. She teetered for a moment and then pitched towards him. He fell back; she came along for the ride, jarring his right shoulder when she landed, but he was too relieved to be upset.
As though on cue, the rain began to lighten. Happy to take a momentary break where he was, sitting in the mud with his weapon in his lap, Jack squinted suspiciously up at the sky.
Abruptly, Carter grabbed his shoulder. He whipped his head back to look at her, but her attention was elsewhere, and he could see the fear in her eyes.
The whole 'action scene' thing is surprisingly addictive.