Research on the interactions between El Niño events and the North American Monsoon System suggests that during past El Niño events, there was a slowing of the onset of monsoon precipitation across the Southwest U.S. (read more)
Originally published in Feb 2015 CLIMAS Southwest Climate Outlook:
Why has it been so cold on the East Coast, and so warm in the Southwest? Where does this fit into climatic patterns? And is this extraordinary or just variability? (read more)
Image Source - NOAA-Earth Systems Resarch Laboratory (ESRL)
A pesky ridge of high pressure over the east Pacific dominated the weather much of November steering storms well to our north and east leaving Arizona with unusually warm and dry conditions. (read more)
On September 10-11, 25 scientists and natural resource managers met at the offices of the International Boundary and Water Commission (IBWC), in El Paso, Texas. Their goal was to use strategic scenario planning techniques to gain insight into environmental and natural resource planning under highly uncertain conditions. Participants included climatologists, meteorologists, geologists, hydrologists, ecologists, biologists, and environmental economists, representing a range of U.S. and Mexican federal agencies, state agencies, universities, and non-governmental organizations. (read more)
September turned out to be quite a month as far as extreme monsoon season weather across Arizona. The month started out rather quiet as the monsoon ridge of high pressure weakened and a trough of low pressure to the north ushered in dry air from the west across the state. This suppressed thunderstorm activity for several days until the monsoon ridge pushed back north helping to bring low level moisture back into the region. (read more)
How Do We Know When the Monsoon is Over?
Across the southwest United States, the start of the summer monsoon season is pretty easy to recognize once you have experienced it firsthand a few times. Typically, one week it's hot and dry, and the next week, it's hot and sticky, but hopefully raining. (read more)
What is the exact criteria to call something El Niño? Is El Niño a continuum or is there a binary switch where it's either an El Niño event or not?
How closely linked is the strength of El Niño with observable effects in the Southwest? Would a weak El Niño look that different from no El Niño at all? (read more)
There’s been a lot of talk about El Niño and ‘busting the drought'. How much can El Niño help with ongoing drought conditions in the West?
Significant amounts of rain fall during the monsoon, why doesn’t that solve our drought problems? (read more)
July started off with a bang with moisture and thunderstorm activity moving into Arizona over the 4th of July weekend. This start date for monsoon thunderstorm activity was very close to the climatological start date of July 3rd, as determined by the old dewpoint definition (three consecutive days with average dewpoints >= 54F) in Tucson. The ‘monsoon ridge’ of high pressure was in an ideal position over the first two weeks of July to guide abundant subtropical moisture into the state, providing fuel for almost daily thunderstorm activity across parts of southeastern Arizona and the high country along the Mogollon Rim. (read more)
On June 25-27, 2014, a team of researchers from CLIMAS and the California-Nevada Applications Program (CNAP) convened a workshop at the Desert Research Institute in Reno, NV. The goal? We wanted to address the complex and uncertain future of Great Basin land management in the Central Great Basin (California and Nevada), and to provide state and federal agency partners with streamlined and purposeful means of incorporating climate change information into land management practice. (read more)
June was a hot and dry month across Arizona with little in the way of precipitation and lots in the way of wind and extreme fire weather. This isn’t all that unusual for June in Arizona, but temperatures were exceptionally warm and passing weather systems brought unwelcome wind which periodically enhanced fire danger to extreme levels. The weather pattern throughout the month was a battle between the strengthening sub-tropical high to our south and late season spring storm pushing through the Southwest from the north. (read more)
Just how old are the forests in the Chuska Mountains in the northeastern part of the Navajo Nation? How might those forests fare in a climate that will be warmer and probably drier than anything they've ever experienced?
In early June I had the chance to tromp around in the woods with a group of experts working to answer these questions. Our intrepid leader was UA Laboratory of Tree Ring Research PhD student Chris Guiterman who—I now know—is a man with a plan. The plan goes something like this...(read more)