CALIFORNIANEVADA 

DROUGHT 

OUTLOOK

JULY 2018

National Integrated Drought 

Information System Drought.gov

Current Drought Conditions

Summer in California and Nevada is the climatological dry season, with the 

exception of monsoon-impacted regions of southeastern California-Nevada. 

According to the U.S. Drought Monitor, drought conditions have not changed 

over the last 2 months, except for expansion of abnormally dry (D0) to moderate 

drought (D1) conditions in northern California due to meteorological drought. As 

of July 24 (Fig. 1), ~39% of California-Nevada was in moderate-extreme 

(D1-D3) drought and another ~45% was abnormally dry. Most drought areas are 

expected to persist into the fall with above-normal temperatures likely. Fig 1. U.S. Drought Monitor for July 24. 

Source: http://droughtmonitor.unl.edu

Regional Climate Update

As California and Nevada continue through their 

climatological dry season, water year totals through 

July have remained below normal across both 

states. Southern Nevada and California are at 

50-70% (or less) of the 1981-2010 normal water 

year precipitation, with just pockets of northern 

California and Nevada receiving above-normal 

precipitation (Fig. 2). Monsoonal precipitation over 

the southeast portions of California-Nevada has 

helped, but has not alleviated drought conditions.

June-July temperatures left California-Nevada 2-6°F 

warmer than normal (Fig. 3). The July 6-7 heat wave was 

record-breaking in California, including maximum highs of 

121°F in San Bernardino and 118°F in Los Angeles counties. 

Smoke from wildfires has been an issue, although not 

atypical for this time of year, including most recently from 

the Ferguson fire that started July 13th (Fig. 4) and has 

closed parts of Yosemite National Park. Reservoir levels are 

generally at or just below historical averages, due to carry 

over from last year’s wet winter and this year’s wet March.

Fig. 2: Percent of normal precipitation (%) for the 

2018 water year to July 23, 2108. Source: HPRCC

Fig. 3: Departure from Normal Temperature (°F), 

May 25 - July 23, 2018. Source: HPRCC

For more information about NIDIS, visit www.drought.gov
Drought & Climate Outlook

• ENSO: Conditions are ENSO-neutral as equatorial sea 

surface temperatures are near-to-above normal across 

most of the Pacific Ocean, and the coupled oceanic and 

atmospheric conditions reflect ENSO-neutral. Given 

recent oceanic warming, NOAA’s ENSO alert system

status is currently an El Niño Watch as the forecaster 

consensus favors the onset of El Niño during the 

Northern Hemisphere fall (65% chance) through winter 

(70% chance).

• Temperature: Warm temperatures are favored over 

California-Nevada through the fall. According to NOAA 

Climate Prediction Center (CPC), there is a 45-65% 

chance of above-normal August-October temperatures 

over the region, with the greatest chances over eastern 

Nevada (Fig. 5).

• Precipitation: According to NOAA CPC, most of California 

and Nevada have equal chances of above, below, and 

normal August-October precipitation (Fig. 5). Drought is 

forecasted to persist through the fall, with potential drought 

relief where above-normal monsoonal precipitation is 

slightly favored in southeastern California-Nevada.

• Wildfire: The National Significant Wildland Fire Potential 

Outlook shows above-normal wildfire potential in AugustSeptember over north-central California-Nevada as well as 

coastal California (Fig. 6). Elevated fire potential will extend 

from the higher elevations of California, across most of the 

Northwest, and most of the Great Basin. 

Fig. 4: Fire and smoke from the Ferguson Fire on July 19, 2018, 

from NASA MODIS. Source: https://www.nasa.gov/image-feature/

goddard/2018/ferguson-fire-jumps-to-near-23k-acres-in-size

Fig. 5: Temperature and precipitation probabilities for 

August to October, 2018. Source: Climate Prediction Center. 

A = chances of Above Normal; EC = equal chances of Above, 

Below, or Normal; B = chances of Below Normal

August 2018 September 2018

Significant Wildland Fire Potential Outlook

Fig. 6: National Significant Wildland Fire Potential Outlooks 

issued July 1, 2018. Red indicates above-normal significant 

wildland fire potential. Source: NIFC Predictive Services

About this Outlook

On July 23, 2018, NIDIS and its partners held this webinar as part of a series of 

drought and climate outlook webinars designed to provide stakeholders in the 

region with timely information on current drought status and impacts, as well as a 

preview of current and developing climatic events. 

A video of and presentations from this webinar can be accessed here: 

https://www.drought.gov/drought/calendar/events-california-nevada-droughtclimate-outlook-webinar-july-23-2018

Contributors

Dave Simeral, WRCC/DRI

Amanda Sheffield, NOAA/NIDIS

Ed Delgado, NIFC

Julie Kalansky, CNAP/SIO

For more information about NIDIS, visit www.drought.gov Follow us Twitter Facebook YouTube