The monsoon season ended not with rain, but with a hot, dry whimper.
Precipitation in September was 34% of normal, with a mere 0.51 inches of rain. That’s nearly an inch less than the month’s average of 1.48 inches.
Even so, Montezuma County remains drought free.
Previous months – especially June and July, which were 486% and 204% of normal, respectively – helped push us beyond the average year to date precipitation, which is 108% of normal.
“It deserves paying attention to,” said James Andrus, a weather observer in Cortez for the National Weather Service. “For the next week, we have nothing but sunny and warm weather forecast. Not a hint of rain, not even a 10% chance of rain.”
Andrus attributed the dry end of September to the La Nina weather pattern.
“La Nina episodes are commonly associated with drier weather in the Southwest. In the wintertime it can also mean colder weather too,” he said.
“Sometimes the pattern’s a joker and the joker in the deck doesn’t conform to the classic La Nina pattern. Even if we’re in the middle of a La Nina pattern, we can have different episodes of weather.”
As far as temperatures go, “we’ve got some interesting temperature quirks,” Andrus said. Several steamy days in late September proved record- breaking.
“It feels like July weather out here, not October,” Andrus said.
- 88 degrees on Sept. 27 broke the 2001 record of 86 degrees.
- 89 degrees on Sept. 28 broke the 2010 record of 88 degrees.
- 90 degrees on Sept. 29 broke the 2001 record of 86 degrees.
- 87 degrees on Sept. 30 tied the 2010 record of that same temperature.
“We’ve got a strong, high-pressure ridge embedded over the western United States, and it’s just filled with hot, dry air,” said Andrus. “What we need is that high pressure ridge to collapse, and get replaced by some low pressure troughs coming in from the Pacific. It’d cool us off and perhaps even bring us some moisture.”
On Sept, 29, that 90 degrees record temperature “became the latest occurrence of a 90-plus degree day in any year for Cortez, resetting the old last-occurrence record of 91 degrees set on Sept. 21, 1937,” Andrus said.
That record got re-reset Oct. 1, which became the first 90-degree day we’ve ever experienced in October.
“You might say it’s a little flag, reminding us of the global warming situation,” Andrus said.