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Monsoon Summary Jun 15-Aug 20

Friday, August 21, 2015

Originally published in the August 2015 CLIMAS Southwest Climate Outlook

The monsoon started off early and strong with several widespread thunderstorms in late June and early July, especially in Arizona, which recorded its second wettest June on record.  Precipitation tapered to some extent in July in Arizona but continued to be frequent and widespread in New Mexico, which recorded its 10th wettest July on record (Figs. 1a-2a). (read more)

El Niño Tracker - July 2015

Monday, July 20, 2015

El Niño conditions continue for a fifth straight month, and at this point, forecasters are relatively bullish that we are witnessing the development of a moderate-to-strong event that could rival 1997 in absolute magnitude later this year. The most recent outlooks from various sources offer a consistent cluster of forecasts calling for a clear El Niño signal that is maintained or even strengthens well into early 2016. Forecasts focused on the persistence of sea-surface temperature (SST) anomalies (Figs.1 - 2) along with weakening trade winds, ongoing convective activity in the central and eastern Pacific, and El Niño-related ocean-atmosphere coupling. (read more)

Image Source - Australian Bureau of Meteorology

Monsoon Summary - (June 15 - July 16)

Thursday, July 16, 2015

After a few anomalous incursions of tropical moisture in early June, we saw an early beginning to the monsoon in mid- to late June, a few weeks ahead of the typical start date (Fig. 1). Regional dewpoint/humidity readings for June illustrate the multiple incursions of tropical moisture, followed by the onset of monsoon conditions later in the month (Fig. 2). (read more)

June 2015 SW Climate Podcast - Tropical Storms, Monsoon, Wildfire & El Niño

Wednesday, July 1, 2015

In the June 2015 edition of the CLIMAS SW Climate Podcast, Mike Crimmins and Zack Guido recap the month of June, including the quick transition from cool and wet to hot and muggy conditions.  The discuss the impact of tropical storms on the region, the early start to this season, and what this may or may not mean in terms of relationship to monsoon patterns.  They turn to El Niño, and the impact the El Niño signal may be having on the region, both looking back at the past few months, but in particular looking forward at what this could mean for the southwest in terms of precipitation patterns over the next 12 months. (read more)

El Niño Tracker - June 2015

Friday, June 19, 2015

Originally Published in the June 2015 CLIMAS SW Climate Outlook (SWCO)


El Niño conditions continued for a fourth straight month with no signs of weakening or disorganizing. Forecasts focused on the persistence of sea-surface temperature (SST) anomalies (Figs.1 - 2) along with weakening trade winds, ongoing convective activity, and El Niño-related ocean-atmosphere coupling. Despite the high degree of uncertainty associated with forecasting El Niño this time of year (the so-called spring predictability barrier), the most recent outlooks from various sources offer a consistent cluster of forecasts calling for a clear El Niño signal that is maintained or even strengthening. (read more)


Image Source - Australian Bureau of Meteorology

Southwest Climate Outlook June 2015

Thursday, June 18, 2015

Originally Published in the June 2015 CLIMAS SW Climate Outlook (SWCO)


Precipitation: In the past 30 days, most of New Mexico and much of northern Arizona recorded well-above-average precipitation (Fig. 1).  Climatologically, we are in one of the drier times of year for the Southwest, so this precipitation and humidity (mostly tied to early season Pacific tropical storm activity) helped tamp down fire risk. This respite was short-term however, as water-year observations since October 1 reflect persistent and ongoing drought conditions, with most of the western U.S. recording well-below-average precipitation (Fig. 2).  Notable exceptions are New Mexico, Colorado, Wyoming, and Montana, but with most recent precipitation falling on the eastern side of the Continental Divide. (read more)


Image Source - NOAA/NWS - Advance Hydrologic Prediction Service

2015 El Niño Tracker

Friday, May 22, 2015

Originally published in the May 2015 CLIMAS SW Climate Outlook


El Niño continued for a third straight month, with no signs of weakening or dissipating. Forecasts keyed in on persistent sea surface temperature (SST) anomalies (Figs. 1–2), along with weakening trade winds, ongoing convective activity, and El Niño-related ocean-atmosphere coupling. If these conditions continue, we are likely to see the effects of a moderate El Niño event–or stronger if conditions continue to strengthen. Spring forecasts have a higher degree of uncertainty, owing to the so-called spring predictability barrier, a likely source of vacillations in recent forecasts. (read more)

Image Source - Australian Bureau of Meteorology

Winter/Spring Recap 2014-2015

Friday, May 22, 2015

Originally published in the May 2015 CLIMAS SW Climate Outlook


It may not be news to anyone who follows weather forecasting and climate outlooks, but winter 2014–2015 did not play out as expected. Last year, long-term seasonal forecasts keyed in on conditions favorable to the development of an El Niño event and suggested we were more likely to see above-average precipitation in our winter months.  This was welcome news to a region that has been affected by a long-term and persistent drought, but rather than sustained above-average precipitation, we saw highly variable precipitation between October 2014 and April 2015 (Fig. 1) and cumulative water year-to-date precipitation that is below average across much of Arizona and parts of New Mexico (Fig. 2 on page 2).  Temperature was much less variable, with record or near-record warm average temperatures across most of the western U.S. (Fig. 4 on page 2). So what does this mean for some key areas of concern in the Southwest?  (read more)

Southwest Climate Outlook May 2015

Thursday, May 21, 2015

Originally published in the May 2015 SW Climate Outlook


Precipitation: In the past 30 days, most of New Mexico and much of central Arizona recorded well above-average precipitation (Fig. 1). Climatologically, this is one of the drier times of year for the Southwest, so any substantive precipitation during this timeframe is generally unexpected but welcome, as it helps tamp down fire risk. Water year observations since October 1 demonstrate the persistent and ongoing drought, with most western states, including Arizona, recording large areas of below-average to well below-average precipitation (Fig. 2). New Mexico and the eastern side of Colorado, Wyoming, and Montana have benefitted from some late season storms, but that rainfall on the other side of the Continental Divide, does not necessarily help the water situation in the Southwest.  (read more)

Image Source - NOAA/NWS - Advanced Hydrologic Prediction Service

Image Source - NOAA/NWS - Advanced Hydrologic Prediction Service

Mini-Podcast/News - Southwest Climate Update - May 1, 2015

Monday, May 4, 2015

Podcast introduction: We're introducing a new podcast series (CLIMAS SW Climate Update) that focuses on quick and timely reporting on important climate news and information. We will emphasize stories that relate to the southwest, but we'll also include other climate related news that illustrate the impact of climate on national or global scales.  And Mike, Zack, and Ben will still take a deeper look at southwestern climate issues in the monthly CLIMAS Southwest Climate Podcast. This episode, we're focused on record warm temperatures, drought, and snowpack across the west, along with a few stories that illustrate the downstream impact of these conditions.

El Niño Tracker - April 2015

Friday, April 17, 2015

This was originally published in the April 2015 Southwest Climate Outlook


Strong signals in early 2014 stalled, delaying El Niño’s onset until last month, when ocean-atmosphere coupling and an additional Kelvin wave indicated more favorable conditions. Despite this late start, El Niño continued for a second consecutive month. Recent increases in sea surface temperature (SST) anomalies (Fig.1 - 2) and ongoing convective activity associated with El Niño-favorable conditions indicate we might be witnessing a two-year El Niño event. These forecasts rely on projections during a time of increasing uncertainty, and the so-called “spring predictability barrier” continues to make it difficult to anticipate how seasonal changes will help or hinder El Niño. (read more)

Southwest Climate Outlook April 2015 - Climate Summary

Thursday, April 16, 2015

Precipitation: In the past 30 days, most of the southwestern U.S. received below-average precipitation (Fig. 1). The winter wet season is wrapping up, and instead of above-average precipitation (as many of the El Niño influenced seasonal forecasts suggested), water year observations since October 1 show below-average precipitation across much of Arizona and portions of New Mexico. The situation is direr in other western regions, with California, the Pacific Northwest, and the Intermountain West recording significantly below-average winter precipitation (Fig. 2). (read more)

El Niño Tracker - Southwest Climate Outlook February 2015

Friday, February 20, 2015

Originally published in the Feb 2015 CLIMAS Southwest Climate Outlook

A definitive 2014–2015 El Niño forecast remains elusive. Weak El Niño conditions have continued in 2015, but recent backsliding in SST anomalies (Fig. 1), especially in the Niño 1-2 regions (Fig. 2), along with the ongoing lack of coordination between atmospheric and oceanic conditions, give little confidence that the 2014–2015 event will be characterized as anything more than a weak El Niño. (read more)

Image Source - NOAA-National Climatic Data Center

El Niño Tracker - January 2015

Friday, January 23, 2015

Just when it looked like we were getting a more definitive answer regarding El Niño, ongoing lack of cooperation on the part of the atmosphere continues to muddy forecasts moving into 2015. Sea surface temperatures (SSTs) remain elevated across much of the equatorial Pacific Ocean (Fig. 1), and while temperature anomalies in the Niño 3.4 region are within the range of a weak El Niño event, they have declined in the past month (Fig. 2). It is a common refrain in forecast bulletins that a lack of coupling between ocean and atmosphere is responsible for decreased confidence in an El Niño event this winter. Additionally, a lack of temperature gradient along the equatorial Pacific and little in the way of El Niño wind patterns further reduce confidence that a stronger event is on the horizon. (read more)

Jan 2015 SW Climate Podcast: 2014 Year in Review, and Stuck in El Limbo

Wednesday, January 21, 2015

In the January Southwest Climate Podcast, Zack Guido is back and joins Mike Crimmins to discuss the state of the climate in 2014, including the record year for Arizona and the near record year for New Mexico.  They also talk about weather systems that affected our most recent temperature and precipitation patterns, the ongoing uncertainty with El Niño, or as some have started referring to it, "El Limbo", and the state of precipitation and drought in the southwest.  They wrap things up looking at the seasonal outlooks and the projected trends for the coming year. (read more)

Nov 2014 SW Climate Podcast: A Warm End to Autumn and Waiting for ENSO

Wednesday, December 10, 2014

In the November Southwest Climate Podcast, Ben McMahan and Mike Crimmins discuss the warm autumn weather in the southwest, the transition to winter weather patterns, the ongoing uncertainty of El Niño forecasts, a recap of El Niño conditions and definitions, and the possibility of interaction between El Niño conditions and weather patterns in the southwest looking forward.  read more

El Niño Tracker Update - Late November 2014

Friday, November 21, 2014

From the Nov 20, 2014 Southwest Climate Outlook

The long-awaited El Niño event projected to develop during winter 2014 – 2015 has yet to send a decisive signal regarding an official start, but a number of factors have increased forecasters’ confidence that one will emerge. The strength of this event still remains in question, however with the most likely projection still centering on a weak or weak to moderate event (

Southwest Climate Outlook November 2014

Thursday, November 20, 2014

The Nov 20, 2014 Southwest Climate Outlook (SWCO) includes a regional climate summary, an update on El Niño, Arizona and New Mexico reservoir levels, a look back at the tropical storms that impacted the southwest in 2014, and a reminder about the CLIMAS video podcast series on youtube (read more)

Monsoon Recap - June 15 - Sept 30, 2014

Friday, October 17, 2014

Looking back on the 2014 monsoon, a simple characterization of the season as ‘normal’ or ‘average’ (or above or below these thresholds) is difficult, given the spatial and temporal variability of monsoon storms. The cumulative seasonal totals provide one way of characterizing the monsoon, and by those metrics, the Southwest saw an average to above-average summer rainy season, with much of Arizona and New Mexico receiving well above-average rainfall. (read more)

This post was originally published as part of the October 2014 Southwest Climate Outlook

2014/2015 El Niño Tracker: Oct 16, 2014

Thursday, October 16, 2014

An El Niño Watch, issued by the NOAA Climate Prediction Center (CPC), continues for the seventh consecutive month as signs of an emerging El Niño are just on the horizon, but not quite here yet. Another slug of warm water (also known as a Kelvin wave), has been making its way across the Pacific Ocean from west to east just below the surface and is poised to emerge and help warm sea surface temperatures in the eastern Pacific over the next month or so...(read more)

This post was originally published as part of the October 2014 Southwest Climate Outlook

Monsoon Summary (June 15 – Sep 18)

Friday, September 19, 2014

We are nearing the end of the 2014 season, and while it is difficult to characterize the highly variable day-to-day storms of any monsoon as “normal,” we have had a fairly typical if not above-average monsoon season in terms of precipitation. Regional assessment is complicated by the effects of a few extreme events that amplified precipitation amounts in parts of Arizona and New Mexico and caused an entire month’s or year’s worth of precipitation to fall in a single storm. (read more)

This post was originally published as part of the September 2014 Southwest Climate Outlook

El Niño Tracker - Sept 2014

Thursday, September 18, 2014

The song remains the same this month with El Niño not quite here yet, but probably soon. This is now the seventh consecutive month since the NOAA Climate Prediction Center issued an “El Niño Watch” last March. The signs are a bit stronger once again, but it is getting late in the game...(read more)

This post was originally published as part of the September 2014 Southwest Climate Outlook

Monsoon Summary (June 15 - Aug 19)

Friday, August 22, 2014

The 2014 monsoon can be characterized many ways—the amount and intensity of rain has been spotty both spatially and temporally, the humidity has been persistently high, and precipitation has improved short-term drought conditions in many areas. Certainly it cannot be characterized as a dud. (read more)

This post was originally published as part of the August 2014 Southwest Climate Outlook

El Niño Watch - Aug 21, 2014

Thursday, August 21, 2014

An “El Niño Watch” continues this month as issued by the NOAA Climate Prediction Center several months ago. The watch is just that: we are waiting and watching for the development of a full-fledged El Niño event that has yet to materialize across the equatorial Pacific Ocean. Several indicators of El Nino-Southern Oscillation (ENSO) status declined, moving back towards ENSO-neutral values over the past month instead of leaning towards an El Niño event as they had been.  These shifts included slight cooling in the eastern Pacific Ocean and near-average wind patterns along the equator. But for those cheering on the development of an El Niño event, not all hope is lost (read more).

This post was originally published as part of the August 2014 Southwest Climate Outlook

Recap: Drought and Water Supplies in the Southwest - 1075' Shortage on the Colorado River

Wednesday, August 13, 2014

This week, we released the 5th episode in the CLIMAS podcast series[1] 1075' - Shortage on the Colorado River, which explores what a shortage declaration on the Colorado River would mean to those living in the Southwest.  In this post - Ben McMahan recaps some of the key issues that formed the impetus for this podcast series, summarizes the podcast episodes, and gives some backstory from folks who have been writing about the Colorado River (Basins) for years (read more)

1075' - Shortage on the Colorado River Ep. 5 - Tucson Water & Muncipal Water Issues

Tuesday, August 12, 2014

1075’ – Shortage on the Colorado River is a CLIMAS podcast series that explores what the first shortage declaration on the Colorado River would mean to those living in the Southwest.

In this episode, CLIMAS climate scientist Zack Guido speaks with Alan Forrest, Director of Tucson Water, about various strategies that Tucson implemented to deal with potential water shortages, the conservation and recapture efforts that areas of municipalities in Southern Arizona, and the practical realities of providing municipal water to an growing population in the southwest. (read more)

1075' - Shortage on the Colorado River Ep. 4 - CAGRD (Dennis Rule)

Tuesday, August 5, 2014

1075’ – Shortage on the Colorado River is a CLIMAS podcast series that explores what the first shortage declaration on the Colorado River would mean to those living in the Southwest.

In this episode, CLIMAS climate scientist Zack Guido talks to Dennis Rule, manager of the Central Arizona Groundwater Replenishment District (CAGRD), about the importance of CAGRD in the management of Arizona groundwater and potential impacts on the system from continued drought in the Colorado River Basin. (read more)

1075' - Shortage on the Colorado River Ep. 3 - Shortage Impacts on the CAP

Tuesday, July 29, 2014

1075’ – Shortage on the Colorado River is a CLIMAS podcast series that explores what the first shortage declaration on the Colorado River would mean to those living in the Southwest.

In this episode, CLIMAS climate scientist Zack Guido and Mohammed Mahmoud, planning analyst with the Colorado River Programs department at the Central Arizona Project (CAP), discuss the CAP and its role in delivering Colorado River water throughout Arizona, as well as how a shortage would impact the CAP system. (read more)

Southwest Climate Podcast: Strong Start for the Monsoon & Groundhog Day for El Niño Forecasts

Thursday, July 24, 2014

In the July Southwest Climate Podcast, CLIMAS climate scientists Zack Guido and Mike Crimmins talk about the solid start to the monsoon, and seemingly inevitable monsoon breaks (like we just experienced). They also discuss the "inevitability" of this fickle El Niño event. There’s a feeling of Groundhog Day with these forecasts—and there continues to be uncertainty regarding the strength and duration of this El Niño event. (read more)

1075' - Shortage on the Colorado River - Podcast Ep. 2 - Stressors on the River

Tuesday, July 22, 2014

1075’ – Shortage on the Colorado River is a CLIMAS podcast series that explores what the first shortage declaration on the Colorado River would mean to those living in the Southwest.

In this episode, CLIMAS climate scientist Zack Guido hosts three University of Arizona experts, Bonnie Colby, George Frisvold and Kiyomi Morino, to discuss water supply and demand in the Colorado River basin. This podcast explores stressors on the Colorado River Basin, how these stressors may change over time, and how these changes may affect management and behaviors across the Southwest.(read more)

Southwest Climate Outlook July 2014

Friday, July 18, 2014

The Southwest Climate Outlook is published on the third Thursday of every month, and focuses on the climate & weather patterns for the SW more generally, and Arizona and New Mexico in particular.  This month's issue includes sections on precipitation and temperature for the past month or so, reservoir totals for AZ & NM, drought and monsoon trends, a summary of the fire season, an El Niño watch, and a look forward at the precipitation and temperature outlook for the next 30-90 days (read more).

1075' - Shortage on the Colorado River, A CLIMAS Podcast Series

Monday, July 14, 2014

1075’ – Shortage on the Colorado River is a CLIMAS podcast series that explores what the first shortage declaration on the Colorado River would mean to those living in the Southwest.

In this episode, we take a broad view of the Colorado River Basin, exploring how the river is managed, who uses the water, and what a potential shortage could mean for the system. Our guest is Doug Kenney, Director of the Western Water Policy Program, a division of the Getches-Wilkinson Center for Natural Resources, Energy and the Environment, at the University of Colorado School of Law.  (read more)

Recent Variations in Low-Temperature and Moisture Constraints on Vegetation in the Southwestern U.S.

Friday, April 19, 2013

Dr. Jeremy Weiss, a senior researcher with UA’s Environmental Studies Laboratory, will discuss the importance of seasonality and elevational gradients for understanding the effects of drought and warming on vegetation in topographically complex regions like the Southwest, and explain how projected changes in future regional climate may potentially further or alter these effects. (read more)

Field of Dreams, or Dream Team? Assessing Two Models for Drought Impact Reporting in the Semiarid Southwest

Friday, March 22, 2013

To make decisions about drought declarations, status, and relief funds, decision makers need high quality local-level drought impact data. In response to this need in Arizona, the Arizona DroughtWatch program was created, which includes an online drought impacts reporting system. Despite extensive and intensive collaboration and consultation with the intended public participants, Arizona DroughtWatch has had few consistent users and has failed to live up to its goal of providing decision makers or the public with high quality drought impacts data. (read more)

Drought Impacts on Dust and Health in New Mexico

Friday, March 1, 2013

Dust storms create both health issues and transportation hazards. Valley Fever is endemic to the border region and gets carried with the dust. Interstates and local highways are often closed for hours in an attempt to avoid accidents and injuries. Windblown dust concentrations can be very high when strong winds occur during extended droughts - creating “exceptional episodes” of poor air quality. Air quality in rural areas of New Mexico and along the US/Mexico border is normally acceptable and well below the US EPA’s air quality standards for particulate matter. But these episodes expose millions of people to particulate levels that exceed air quality standards. (read more)

Southwest Climate Podcast: Arizona "Blizzard" - Drought Remedy?

Friday, February 1, 2013

Was the "blizzard" in February unprecedented for Arizona, and did climate change play any role? In this month's podcast, Gregg Garfin and Zack Guido discuss this and the influence the storm and recent temperatures had on the state's snowpack. They also explore the status of drought in both Arizona and New Mexico, and what the precipitation forecast looks like for the next few months.