#Drought news: April-July 2020 was the 3rd driest on record for #Colorado

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

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

This Week’s Drought Summary

This U.S. Drought Monitor week saw continued intensification of drought across parts of the western U.S. including Northern California, the Great Basin, Southwest, and parts of the Intermountain West where hot and dry conditions continued and large wildfires burned in California and Colorado. In Northern California, the National Interagency Coordinator Center is reporting 34 uncontained large fires with approximately 1,276,751 cumulative acres burned (all active fires) and more than 11,000 personnel deployed to the region. Further east, drought-related conditions continued to deteriorate in areas of West Texas where significant rainfall deficits (4 to 8 inches) have been mounting during the past 90 days as well as extreme heat and drying winds that have stressed crops and degraded rangeland conditions. In the Trans Pecos region of western Texas, the August 2019 to July 2020 period was the warmest on record—according to the National Oceanographic and Atmospheric Administration (NOAA) National Centers for Environmental Information (NCEI). Along the Gulf Coast of Louisiana, Tropical Storm Marco made landfall this week, but fortunately weakened before making landfall causing no significant damage. A much more powerful storm, Hurricane Laura (Category 4), is expected, however, to make a Gulf Coast landfall along the border of Louisiana and Texas on Thursday (August 27)—where a life-threatening storm surge, hurricane-force winds, and widespread flash flooding are expected. In the Midwest, above-normal temperatures and dryness in Iowa during the past 90-day period (3-to-7 inch rainfall deficits) led to expansion of areas of drought statewide. In the Northeast, areas of drought intensified in portions of the region including New Hampshire where streamflow levels were well-below-normal level (<10th percentile) and reports of some agricultural impacts emerged…

High Plains

On this week’s map, areas of Moderate Drought (D1) expanded in the following areas: northwestern and central North Dakota, southwestern and eastern South Dakota, and eastern and western portions of Nebraska. In eastern South Dakota, corn has been drying prematurely as a result of the recent heat and strong winds. For the week, average temperatures were well above normal across the Dakotas, Nebraska, and the plains of Colorado, Wyoming, and Montana—ranging from 2-to-10+ degrees above normal. Further south, Kansas experienced cooler-than-normal temperatures (2-to-6 degrees) for the week. Overall, the region was mainly dry with some light accumulations (generally < 1.5 inches) observed in eastern North Dakota, southern South Dakota, and western Nebraska…

West

During the past week, numerous large wildfires continued to burn across California leading to mandatory evacuations in some communities around the Bay Area and in other locations in Northern California. The wildfires have been creating unhealthy air quality conditions downwind of the fires in California as well as in western Nevada, and southern Oregon —with smoke plumes extending as far as away as the Midwest. During the past week, the West saw some minor cooling compared to the record-setting heat of last week; but average temperatures were still well above normal across the most of the region. On the map, areas of drought expanded and intensified across California, Nevada, and the Four Corners States. In the Four Corners states, a combination of factors have led to the current drought depiction on the map—starting with an extended period of above-normal temperatures across Arizona, Colorado, and New Mexico beginning in mid-April and extending into mid-June. This warming triggered a premature melting of the snowpack across the mountain ranges of the Colorado River Basin. As summer continued, the extreme heat and a weak monsoon exacerbated the situation with numerous heat-related records broken across the region during July and August. According to NOAA NCEI, the April-July 2020 period was the 2nd driest on record in the Southwest Climate Region (Arizona, Colorado, New Mexico, Utah) while on a state level, the May-July 2020 period was the 2nd warmest on record for both Arizona and New Mexico. In terms of precipitation, April-July 2020 was the 3rd driest on record for Colorado, 4th driest for New Mexico, 5th driest for Colorado, and 6th driest on record for Utah. As of August 1, statewide reservoir storage was slightly below normal in California, Colorado, Nevada, and Oregon with New Mexico worse off at ~50% of normal while above-normal levels were observed in Arizona, Idaho, Montana, Utah, Washington, and Wyoming…

South

On Monday, Tropical Storm Marco made landfall near the mouth of the Mississippi River after weakening significantly thus sparing the residents of the Gulf Coast of Louisiana any significant impacts while a strengthening Hurricane Laura is expected to make landfall as a dangerous hurricane early Thursday morning. On this week’s map, drought intensified (due to continued hot temperatures and mounting precipitation deficits) across Texas with western Texas as a focal point of deterioration. According to NOAA NCEI, the Trans Pecos Climate Division (Texas, Division 5) observed its warmest July on record as well as its warmest August-July period on record. Elsewhere in the region, drought intensified on the map in southwestern Oklahoma where 4-to-6 inch rainfall deficits, since June 1, exist and rangelands reportedly are in poor condition. For the week, average temperatures continued to be above normal (2 to 8 degrees) across Far West Texas while areas to the east were below normal (2 to 8 degrees). In terms of precipitation, moderate accumulations (2 to 5 inches) were observed in portions of eastern Louisiana and southern Mississippi while some light precipitation (generally <1 inch) was observed along the Texas Gulf Coast and central Texas…

US Drought Monitor one week change map ending August 25, 2020.

Looking Ahead

The NWS WPC 7-Day Quantitative Precipitation Forecast (QPF) calls for very heavy rainfall accumulations in association with Hurricane Laura making landfall along the Gulf coast of Louisiana and Texas. Along the coast, rainfall accumulations are expected to range from 3 to15 inches while areas inland in the Lower Mississippi River Basin are expected to see moderate-to-heavy accumulations (2-to-10 inches). In the Midwest, moderate rainfall accumulations (2-to-5 inches) are expected across parts of the region including Missouri, Iowa, Minnesota, Wisconsin, and Michigan as well as in parts of the Northeast. Out West, generally dry conditions are forecasted with the exception of some light precipitation (generally <1inch accumulations) in isolated areas of Arizona, New Mexico, and Colorado. Further northward, isolated mountain showers and thunderstorms are expected in the Northern Rockies of Wyoming and Montana with light accumulations (generally <1 inch). The CPC 6-10-day Outlook calls for a moderate-to-high probability of above-normal temperatures in the Far West, Southwest, South, Southeast, and Mid-Atlantic states, while a high probability of below-normal temperatures are expected across the remainder of the West, Plains states, and the Midwest. In terms of precipitation, there is a moderate-to-high probability of above-normal precipitation across most of the eastern half of the U.S., Northern Rockies, and Alaska. Drier-than-normal conditions are forecast for the Pacific Northwest, Four Corners states, and the Gulf Coast region of Texas and Mississippi.

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