#Drought news: D0 eliminated in Kiowa, Cheyenne, and Prowers counties

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

Summary

A series of storm systems swept across the lower 48 States, generating wet weather that soaked many portions of the contiguous U.S., including a second round of heavy rains that provided drought improvement and relief to the southern Great Plains and Mississippi Delta. Unfortunately, the rains were accompanied by severe weather and flash flooding in Texas, including a record daily total of 14.99 inches at Austin (5.76 inches in one hour) on October 30, and an EF2 tornado in Floresville that damaged the high school. Additional dryness or drought relief from moderate to heavy rains (more than 2 inches) also occurred across most of the Southeast, west-central Corn Belt and western Great Lakes region, Ohio and Tennessee Valleys, much of the Atlantic Coast States, and the Pacific Northwest, northern Rockies, and Sierra Nevada. Heavy precipitation also fell on interior and northeastern Puerto Rico and along the southeastern Alaskan Panhandle. Weekly temperatures generally averaged above to much-above normal in the lower 48 States, with near to below-normal readings limited from the Southwest northeastward into the middle Mississippi Valley, and in interior New England…

California and Great Basin

An early-season, moisture-laden Pacific storm system brought beneficial precipitation (including snows to higher elevations) to extreme northwestern and central California, including 2-3.5 inches of precipitation to the Sierra Nevada and northeastward across west-central and northeastern Nevada. The precipitation (and snow) was an early bonus to the 2015-16 Water Year in the Sierras, but with 4 consecutive years of drought, this precipitation was just a start to moisten the soils for hopefully more (frozen preferred) precipitation this winter, thus no changes were made in the Sierras. However, according to the NRCS Snotel sites, it was refreshing to see the Sierra average basins WYTD (since Oct. 1) precipitation and snow water content at 152-170% of normal and 608-1150% of normal, respectively, as of Nov. 3, but one must remember that normal are quite small early in the Water Year, so huge percentages can occur with a wet start (but better wet than dry). Additionally, the Impact Lines were redrawn to reflect where recent wetness has occurred (L only) versus where much-below normal short-term precipitation was recorded (SL).

In contrast, the past 6 months have been unusually wet in parts of the semi-arid Great Basin (200-300% of normal precipitation, surpluses of 4-8 inches), especially in extreme eastern California (east of Sierra range) and western Nevada. This has led to minimal fall wild fires, decent pasture and range conditions, and adequate soil moisture. Although the Nevada statewide reservoir levels were still dismal (Oct. 1: at 5% capacity, normal=35%) and will require ample mountain snowpack this winter, the past 6 months wetness (from all tools) in a semi-arid environment is significant and a good start to the 2015-16 Water Year. Therefore, D4 was improved to D3 in western Nevada (southwest Pershing, northwest and southern Churchill, southern Lyon, and western Mineral counties) and eastern California (northern Mono county) to reflect this recent moisture. In addition, some D3 to D2 improvement was made farther south along the CA-NV border (southern Nye and east-central Inyo counties) where the past 3-6 months have NOT been arid…

Mississippi Delta and Southern Plains

Extreme precipitation events seem to be the norm in this region as a sudden (1-2 weeks) end to the 3-month flash drought neared reality. Two swaths of copious rains (more than 8 inches), one between San Antonio and Austin, TX, and another from Houston, TX, to north of Alexandria, LA, produced flash and river flooding, with at least 5 fatalities in Texas. Needless to say, after the previous week’s rainfall, these amounts were more than enough to eliminate the remaining D1 and D0 across south-central and southeastern Texas and the southern two-thirds of Louisiana. In addition to these incredible totals, widespread moderate to heavy rains (2-6 inches) were measured across the eastern two-thirds of the state, south-central Oklahoma, central Arkansas, nearly all of Louisiana and the southern two-thirds of Mississippi. A widespread 1- to occasionally 2-category improvement was made in these areas as all D2 was removed. According to the Texas Water Development Board, statewide reservoirs stood at 82.1% full as of Nov. 4, continuing to climb after falling from 85% to 77% full during the flash drought. In addition, the Texas state climatologist John Nielsen-Gammon estimated that October 2015 statewide precipitation stood at 6.51 inches (previous Oct. record 6.26 inches in 1919), making 2015 the third year with at least two monthly records (May and October). The other two years were 2004 (June and November) and 2007 (March and July). Short to very short topsoil moisture dropped to 16, 19, 5, and 16% in Texas, Arkansas, Louisiana, and Mississippi, respectively, as of Nov. 1, down from 32, 48, 39, and 58% the previous week, according to NASS/USDA. Residual areas of D1 and D0 remained where 2-week precipitation totals were lower and larger 90-day deficiencies remained, however, the numerous reports of drought impacts a few weeks ago have instead turned to excessive moisture problems…

Northern and Central Plains

Weekly totals were much lower across the northern and central Plains as compared to areas to the south and east; however, in North Dakota, timely rains (0.2-0.7 inches) helped improve the condition of the winter wheat while farmers utilized the dry weather to continue harvesting corn and sunflower seeds which were done well ahead of normal. Even though little or no rain fell on South Dakota, 90-day surpluses, lower temperatures, and minimal evapotranspiration have kept the D0(S) from worsening. In southern Nebraska and eastern Kansas, light to moderate (0.3-0.9 inches) rains generally kept conditions stable, although a reassessment of short-term tools led to a slight redraw of the D1 areas in Kansas and D0 in southwestern Nebraska. In [southeastern] Colorado and southwestern Kansas, 0.6-1.5 inches of rain, locally to 2.5 inches, plus heavy rains from last week, were enough to eliminate the D0 in Kiowa, Cheyenne, and Prowers counties (Colorado), and Greeley and Hamilton counties (Kansas)…

Pacific Northwest and Northern Rockies

A constant barrage of Pacific moisture and storm systems brought daily precipitation, quite heavy during mid-week, to coastal Washington, northwestern Oregon, the northern Cascades, and northern Rockies. For the week, totals ranged between 6-15 inches in the first three areas, and 2-6 inches in the latter region. With this week’s copious amounts and wet weather during the past 3-4 months, 1-category improvements were made to areas with the greatest amounts, namely western Washington and northwestern Oregon (D2 to D1), central coastal Oregon (D3 to D2), western side of Cascades (D3 to D2), northeastern Washington, northern Idaho, and northwestern Montana (D3 to D2), and north-central Montana (D0 to D2 1-cat improvements; Glacier, Pondera, Teton, and Toole counties), the latter which was wet out to 180-days. Similarly, some D0 was removed from eastern Montana as the short-term indices were either normal or wet. Just like many basins in the West, this early Water Year (since Oct. 1) precipitation is welcome to moisten the soils, but it will take ample winter precipitation in the form of mountain snows to truly replenish the depleted reservoirs next spring, especially in Oregon. In contrast, short-term dryness (past 3 months) in central sections of Wyoming expanded the D0(S) in this state…

Southwest

Although precipitation was generally light (about 0.5 inches) across Arizona and New Mexico, slight adjustments were made based upon numerous indices (especially the station SPIs) out to 12-months that depicted wetness across the D1 areas of northern Arizona and northwestern New Mexico in order to better match the conditions in neighboring states (southern Utah and Colorado). This is similar to the changes made in the Great Basin (Nevada). As a result, D1 was improved to D0 across northern and central Arizona and a bit in northwestern New Mexico (Cibola County). In addition, some D1 was returned to southern Yavapai County, AZ, to better reflect long-term deficits. Based upon the Oct. 1 USDA/NRCS statewide reservoir storage data, however, Arizona and New Mexico were still below normal (35% and 28% capacity versus normal of 49% and 42%, respectively), so ample winter precipitation (decent mountain snowpack) is still needed to offset the long-term hydrologic (reservoir) shortages…

Looking Ahead

For the upcoming 5-day period (November 5-9), moderate to heavy (1-3 inches) precipitation is expected from the southern Great Plains northeastward into the eastern Ohio Valley. Light to moderate precipitation (0.5-1.5 inches) is forecast from Louisiana eastward to the North Carolina Outer Banks, southern Florida, the central Great Lakes region, parts of the Rockies, and the Pacific Northwest. Little or no precipitation should occur in most of California and the Great Basin, the High Plains, and the Northeast. Temperatures should average below-normal in the western third of the Nation, and above normal in the northern half of the Plains and eastern third of the U.S.

For the ensuing 5 days (November 10-14), the odds favor above median precipitation in the Pacific Northwest, central Rockies, north-central and southern Plains, Midwest and Great Lakes region, New England and mid-Atlantic, and most of Alaska except sub-median chances in the southwest. Below median odds are likely from central California northeastward into western North Dakota. Below-normal temperatures are favored in the West and Alaska, and above-normal readings in the eastern half of the Nation.

Click on a thumbnail graphic below to view a gallery of US Drought Monitor maps for early November since 2010.

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