July delivered Cortez a break from the drought and spring heat wave, with above-average rainfall spanning the month and arriving, as local weather spotter Jim Andrus described it, precisely on time.
“The monsoon arrived right on schedule, just like a train arriving at the train station,” Andrus said, “and they had lots of tanker cars full of rain for us. So, that was a very good start.”
Cortez received 1.60 inches of precipitation over last month, compared with an average of 1.25 inches, according to Andrus’ monthly report for the National Weather Service.
Most rainfall stemmed two major events, though the first of it fell July 9. One event stretched July 20 through 22, producing 1.1 inches and spraying pockets widely across the Four Corners.
It reached the Ferris Fire burned area, causing some flooding and runoff in vulnerable soils. During a presentation at the Dolores Watersheds Collaborative’s workshop Wednesday, members of the U.S. Forest Service’s and U.S. Bureau of Land Management’s BAER (Burned Area Emergency Response) teams provided initial findings.
The discussion relayed impacts of what was characterized as the “first big flush” during a July 21 storm, dropping 3-6 inches of rain in some burned areas.
“The most amount of rain landed in that small, private watershed. … It turned out to be a 500-to-1000-year event,” Shauna Jensen, a hydrologist on the BAER team, told attendees Wednesday.
Jensen added: “We have had that first, damaging storm and when you look at the picture of the Dolores Canyon, some of that stuff has moved already, but you have got your first big flush.”
A hailstorm accompanied by heavy rain and strong winds in Cortez on July 21 swiftly gained the better of several trees. Greater impacts were from flooding.
“It's what I would call an episode. This is where the atmosphere is configured to favor frequent showers,” Andrus said. “With showers, you never know exactly where they're going to fall.”
Andrus said the welcomed reprieve may be temporary as August started with no moisture recorded. He said he’s observing monsoonal moisture flowing from southwest New Mexico to the northeast and middle parts of the state.
NWS meteorologist Gillian Felton said most areas are in drought, despite July’s monsoons. Hummingbirds shuttle more frequently in backyard feeders, Andrus said he’s noticed, while the dry season has left Colorado black bears hurting for food.
Felton said gauges at Cortez Municipal Airport have recorded 3.54 inches of precipitation this year, compared with a normal 6.20 inches based on the station's historical record dating to 1998.
Felton said high pressure in the atmosphere led to the hotter and drier August. It mirrors the forecast for this weekend and weather attendees may be under for Saturday at Escalante Days in Dolores or the city of Cortez’s Summer Send-Off.
“Our high temperatures are looking to be around 10 degrees above normal Friday and through the weekend, although we are expecting a slight cooldown Sunday,” Felton said, but only by a couple of degrees.
Moisture could hit the region early next week, starting slowly late Sunday into Monday. Although, Felton said, the ground is extremely dry. Afternoon relative humidity has fallen into the single digits in parts of the Four Corners.
“The issue is when we start so dry and moisture comes, the rain has a really hard time reaching the ground at first and it tends to evaporate,” Felton said.
Instead, she said these initial storms could generate virga – rain that evaporates before hitting the ground – and gusty winds, while adding better chances for stronger precipitation to arrive Tuesday into Wednesday.
Felton also noted the climate models have recently reduced the amount of rain expected, although overall, its signaling some moisture will return.
awatson@the-journal.com
