An international research team says monsoon storms in the Southwest have become less frequent but more intense, bringing more extreme wind and rain to central and southwestern Arizona than just a few decades ago.
The study, led by scientists with the University of Arizona, compared precipitation records from 1950 to 1970 with data from the 1991-2010 period to verify their climate model, scaled down to capture changes at a resolution of 1.5 square miles. At that level of detail the changes over time became apparent, while models using a 10 square mile grid aren’t able to accurately recreate the precipitation trends. Continue reading “Is global warming changing the Southwest monsoon?”→
Big surge of subtropical moisture possible early next week
FRISCO — Hurricane Norbert, now spinning off the coast of Baja, California, could deliver copious amounts of moisture to Colorado early next, according to the National Weather Service, which is already talking about the potential for regional flash flooding.
The Category 3 storm is expected to weaken gradually during the next few days as it moves northwest over cooler water, but the projected path turns the remnant low pressure system eastward, coming ashore over northern Mexico or southern California late in the weekend.
The exact path will determine how much rain falls in Colorado, but National Weather Service forecast maps are showing widespread rain across Colorado, with a bullseye over the north-central mountains.
Grand Junction-based National Weather Service forecasters say subtropical moisture will increase across the Great Basin and western Colorado Monday as a low pressure area off the SoCal coast directs Nortbert’s remnants and more monsoon moisture northeastward.
Storms will be widespread by Monday afternoon with the potential for heavy rain and small hail, as well as a chance for flash floods and debris flows.
Energetic monsoon brings moisture surplus to many areas
By Summit Voice
FRISCO — An energetic and widespread monsoon weather pattern brought above normal precipitation to much of the West in August, with a bullseye of moisture in southern Idaho, extending across western Wyoming, Montana, northeastern Utah and into northwestern Colorado. Some locations in the region saw up to 800 percent of average precipitation. Continue reading “Climate: Wet West in July”→
FRISCO — Monsoon season just won’t quit in Colorado this year. That’s a boon for mushroom lovers, who continue to report good finds around the high country, and it’s also dampened the fire season across much of the state. But while the stream of moisture feels summer-like, there’s already been a subtle shift in the quality of the light. We’re closer to the equinox than the solstice now, and the sun slants in from a noticeably different angle at sunset. Continue reading “Morning photo: Twilight set”→
FRISCO — Flashes of lightning, loud thunder and heavy rains Friday marked the start of Colorado’s summer monsoon season. The one- to 2-month period when moist and warm air flows northward from the subtropics may not be as dramatic as the Asian monsoon, but it’s still a critical piece of the state’s overall weather picture, providing abundant moisture just at the time when forests and fields are reaching their driest point. Continue reading “Colorado: Monsoon arrives right on schedule”→
New technique focuses on late-summer tree ring growth to pinpoint seasonal climate patterns
By Summit Voice
SUMMIT COUNTY — A detailed new study of tree rings in the Southwest shows that patterns of alternating wet and dry seasons observed since the 1950s is not the norm. Rather, the analysis suggests that, during historic decadal droughts, both winter and summer precipitation was below the long-term average.