#Drought news (October 4, 2022): Abundant recent precipitation (locally more than 2 inches) prompted improvements along the western slopes of the #Colorado Rockies. Improvements were also made to N.E. #CO

Click on a thumbnail graphic to view a gallery of drought data from the US Drought Monitor website.

Click the link to go to the US Drought Monitor website. Here’s an excerpt:

This Week’s Drought Summary

Major Hurricane Ian made landfall in southwestern Florida on September 28 and then reemerged offshore of the Atlantic coast, with another landfall near Georgetown, South Carolina two days later. Excessive rainfall (more than 10 inches) caused widespread inland flooding throughout the central Florida Peninsula and heavy rainfall overspread the Carolinas, Mid-Atlantic, and central Appalachians. After a mid-level low pressure system tracked inland from the northeastern Pacific and became stationary over the interior West, heavy precipitation (1 to 3 inches) occurred across northern Idaho along with the north-central Rockies. Therefore, improvements were made across much of the East and north-central Rockies. Conversely, a dry week resulted in an expansion of abnormal dryness (D0) and moderate drought (D1) along with intensifying drought conditions across much of the Great Plains, Mississippi Valley, and Midwest. D1 was added to parts of the Pacific Northwest. A mix of improvements and degradations were made to Hawaii, while Alaska and Puerto Rico remain drought-free…

High Plains

Short and long-term NDMC blends, SPIs, soil moisture, and crop conditions support a 1-category degradation for southern South Dakota, southwestern Nebraska, and parts of Kansas. Pond levels are low in Kansas and limited soil moisture is available for winter wheat planting. Abundant recent precipitation (locally more than 2 inches) prompted improvements along the western slopes of the Colorado Rockies. Improvements were also made to northeastern Colorado due to relatively significant precipitation (more than 0.5 inch) this past week. Following heavy precipitation during early August, little to no rainfall for a six week period resulted in an increase in D1 across southeastern Colorado. Beneficial precipitation during the past 30 to 60 days along with improving soil moisture conditions prompted improvements across parts of Wyoming…

Colorado Drought Monitor one week change map ending October 4, 2022.

West

Late summer heat and increasing 90-day precipitation deficits of more than 6 inches resulted in the addition of short-term moderate drought (D1) to parts of northwest Oregon and western Washington. This new D1 area is supported by 30 to 120-day SPI values, near record low 28-day streamflows for this time of year, and declining soil moisture. Conversely, heavy precipitation (1 to 4 inches) supported a broad 1-category improvement across parts of west-central Montana and the impact was changed from SL to L only. 12 to 24-month SPI values continue to support D1+ throughout western Montana. Based in part on above-normal temperatures during August and September, 1-category degradations were made to parts of southern Idaho. Farther to the north, beneficial precipitation during the past week resulted in a 1-cateogry improvement to northern Idaho. Although Arizona and much of New Mexico were status quo this week, this region will be reevaluated next week as many areas received more than 0.5 inch of rainfall from September 27 to October 3 and it was a wet Monsoon for the Southwest…

South

Due to a very dry pattern during the past month along with periods of above-normal temperatures, a 1-category degradation was necessary for parts of the Ozarks, lower Mississippi Valley, western Gulf Coast, and southern Great Plains. 30-day precipitation deficits exceed 4 inches in eastern Oklahoma and northwestern Arkansas. Much of these areas along with interior portions of southeastern Texas have received less than 0.10 inch of rainfall during the past 30 days. 30-day SPI/SPEI along with NLDAS and NASA SPoRT soil moisture were the primary indicators used in depicting these degradations along with recommendations from regional partners. Low to dry ponds, poor pastures, and cattle selloffs continue to be major impacts for Arkansas and Oklahoma. Although moderate drought (D1) was added to southwestern Louisiana, a broader D1 coverage was not designated this week due to a strong wet signal at 60 days and lack of support from soil moisture indicators. A couple of small D1 areas were added to Tennessee (near Nashville and northeast of Chattanooga), based on SPI/SPEIs and declining soil moisture…

Looking Ahead

From October 6 to 10, mid-level low pressure, the tail end of a front, and enhanced moisture from the East Pacific are expected to bring widespread rainfall (1 to 3 inches) to eastern Arizona, New Mexico, and the northern Texas Panhandle. Elsewhere, across the contiguous United States, little to no precipitation is forecast. Behind a cold front, below-normal temperatures are forecast to shift southeastward across the central and eastern U.S. The first frost or light freeze of the season may affect the Corn Belt. Above-normal temperatures are likely to persist throughout the northwestern U.S.

The Climate Prediction Center’s 6-10 day outlook (valid October 11-15, 2022) expects a variable temperature pattern during this 5-day period. Below-normal temperatures are most likely across the Rockies and Southwest, while above normal temperatures are favored for the Pacific Northwest and lower to middle Mississippi Valley. Probabilities for above-normal precipitation are elevated across the southwestern and south-central U.S. with a likely continuation of a drier-than-normal pattern for the Pacific Northwest.

US Drought Monitor one week change map ending October 4, 2022.

Just for grins (maybe grimaces) here’s a gallery of early October US Drought Monitor maps for the past few years.

#California #water agencies strike an agreement to conserve some #ColoradoRiver supply — KUNC #COriver #aridification

Southern California water agencies have agreed on a deal to cut back on the amount of water they use for the Colorado River, some of which is used to grow crops in the Imperial Valley. Ted Wood/The Water Desk

Click the link to read the article on the KUNC website (Alex Hager). Here’s an excerpt:

Water agencies in southern California announced a new agreement to voluntarily cut back on their total water from the Colorado River use by 9%. The deal is a rare instance of collaboration between water departments representing cities and farms, and comes amid federal pressure to conserve water in the face of historic drought…California’s contribution represents the first public commitment to conserve a specific volume of water among the Colorado River’s basin states since the mid-August deadline passed…The new plan from California proposes a 400,000 acre-foot reduction in water use each year, beginning in 2023 and lasting through 2026. The agencies involved – Metropolitan Water District of Southern California, Imperial Irrigation District, Coachella Valley Water District and Palo Verde Irrigation District – said it’s an effort to help boost low levels in Lake Mead, the nation’s largest reservoir…

Map of the Salton Sea drainage area. By Shannon – Background and river course data from http://www2.demis.nl/mapserver/mapper.asp and some topography from http://seamless.usgs.gov/website/seamless/viewer.htm, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=9707481

The California agencies said they will only take voluntary cutbacks if the federal government provides “funding and commitments on the Salton Sea.” The lake is kept full by irrigation runoff from neighboring agricultural areas. As farmers conserve more water in the Imperial and Coachella valleys, the lake declines causing public health and ecological crises for that valley. Its future has been at the heart of fractious debates in California about its use of Colorado River water.

The All American Canal diverts water from the Lower Colorado River to irrigate crops in California’s Imperial Valley and supply 9 cities. Graphic credit: USGS

Click the link to read “California agencies float Colorado River water cuts proposal” on the Associated Press website (Kathleen Ronayne). Here’s an excerpt:

The agencies, which supply water to farmers and millions of people in Southern California, laid out their proposal in a letter to the U.S. Department of the Interior. It comes as drought exacerbated by climate change continues to diminish the river, and months after the U.S. Bureau of Reclamation first called on users to voluntarily limit their reliance on it. California shares the river’s water with six other states, tribes and Mexico. It has rights to the single largest share and is the last to lose water in times of shortage…California has been under pressure from other states to figure out how to use less as river reservoirs drop so low they risk losing the ability to generate hydropower and deliver water…

Four California agencies use the river’s water: The Metropolitan Water District of Southern California, the Imperial Irrigation District, the Palo Verde Irrigation District and the Coachella Valley Water District. The proposed cuts are contingent on the water agencies getting money from the $4 billion in drought relief included in the Inflation Reduction Act, as well as a commitment by the federal government to help clean up the Salton Sea, a drying lake fed by diminishing runoff from Imperial Valley farms. The letter was scant on details. The agencies said they have “a collection of proposed water conservation and water use reduction opportunities” that would help keep more water in Lake Mead, one of the river’s key reservoirs…It did not list any specific projects, or specify the rate of payment the agencies are expecting. But the federal government has previously said the $4 billion could be used for short-term conservation measures, like paying farmers to leave their fields unplanted, and long-term efficiency projects such as lining canals to prevent water loss.

The Imperial Irrigation District receives a larger share of the river than any other entity. It’s the only source of water for crops in California’s southeastern desert, where many of the nation’s winter vegetables, like broccoli, as well as feed crops like alfalfa are grown.

Colorado River Allocations: Credit: The Congressional Research Service