#Drought news: D0 shows up in the White, Yampa, Colorado, South Platte, and Arkansas basins #ColoradoRiver

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

Summary

A more tranquil weather pattern emerged this week, with light to moderate precipitation falling on the Pacific Northwest, southern High Plains and Rio Grande Valley, western Tennessee Valley, southern Appalachians, and South Carolina, and most of New England. Heavier totals (more than 2 inches) were limited to extreme western Washington, parts of the Rio Grande Valley and southern High Plains, central South Carolina, and along the southeastern Alaskan coast. Elsewhere in the lower 48 States, mostly dry and warm weather was observed, with temperatures averaging more than 6 degrees Fahrenheit above normal across the Far West and the northern halves of the Rockies and Plains. The first 12 days of October have seen little or no rain from eastern Texas to Mississippi and northward from the eastern Dakotas into southern Minnesota and Wisconsin. Unfortunately, this dry pattern has persisted for at least 3 consecutive months in the southern Great Plains and Delta, leading to severe to extreme short-term drought. While a limited period of dry and warm conditions is ideal for the maturation, dry down, and harvesting of summer crops, too much time under such conditions degrades topsoil moisture, pasture conditions, and winter grains growth while creating ideal wild fire conditions…

California and Great Basin

After last week’s widespread and unseasonably heavy (0.5-1.5 inches) rains in southern and eastern California and western and northern Nevada (locally to 2 inches), more typical dry and warm weather returned to the region. There were no changes made this week. The recent wet weather did nothing to offset the long-term drought, but may have aided in the suppression of wild fires as September and October are normally the biggest months for fires in California…

Northern and Central Plains

Short-term dryness (less than 25% of normal precipitation at 30-days, less than 50% at 60-days) warranted an expansion of D0 westward into south-central North Dakota and southward into northeastern South Dakota. The dryness, combined with strong winds and high temperatures, quickly dried out crops and produced blowing dust, with some wind-driven fires over the weekend. Several stations in northeastern South Dakota had one of the ten driest Septembers on record, ranging from Watertown (0.27”) to Clear Lake (0.63”), while stations in the southwest were similarly dry (Rapid City 0.25”, Newell 0.04”, Hill City 0.26”). Several locations in the Plains also set record October highs (degF) including 98 at Broken Bow and Norfolk, NE; 97 at Grand Island and Hastings, NE, Wheaton, MN, and Fargo, ND; 95 at Sisseton, SD; 94 at Pueblo, CO; and 88 at International Falls, MN. Farther south, light rains during the past 2 weeks were not enough to offset development of short-term dryness in northern and southeastern Kansas as warm and windy weather is impacting fall planted crops such as winter wheat and canola. In northwestern Colorado, D0 was introduced to Grand, Routt, Moffat, and Rio Blanco counties based upon low SPIs at 30- and 90-days, and degrading vegetative health and soil moisture conditions…

Pacific Northwest and Northern Rockies

Moderate to heavy precipitation (2-5 inches) fell on western Washington, especially the Olympic Peninsula and northern Cascades, continuing a trend of consistent precipitation (near to above normal amounts) during the past 3 months. Since these two areas had 90-day surpluses and near to above normal average USGS stream flow values, they were improved a category (from D2 to D1), and the Impact type changed to L (from SL). Elsewhere, the precipitation was not great enough (less than an inch) to make any improvements to the drought (coastal Oregon, southern Cascades, extreme northern Rockies), while little or no precipitation fell (interior Oregon and Washington, southern Idaho), keeping them status-quo…

Southwest

Scattered light showers (less than 0.5 inches) were observed across most of Arizona and southwestern New Mexico, with heavier totals (0.5-2 inches, locally to 4.5 inches) measured in southern and eastern New Mexico (in association with the rains in west Texas and the Rio Grande Valley). Nearly all of the significant rains, however, fell on non-drought areas, except for D0 in southern Chaves and eastern Otero counties. This small D0 was trimmed somewhat as the heavier rains fell to its east and west, still leaving deficits at 60-, 90-, and 180-days, and year-to-date. Elsewhere, decent precipitation from last week was enough to offset this week’s drier weather, keeping conditions unchanged…

Looking Ahead

For the upcoming 5-day period (October 15-19), a rather dry weather pattern should exist east of the Rockies, with only light to moderate precipitation expected in the Great Lakes region and New England, and extreme southern Florida. In the West, however, widespread and heavy rainfall (1-3 inches) is possible in the Southwest (southeast California, Nevada, Arizona, Utah, western New Mexico, southwest Colorado) and western Washington, with lighter amounts in Idaho, Oregon, and western Wyoming and Montana. Temperatures should average below normal in the eastern third of the Nation, with much above normal readings from the Plains westward.

For the ensuing 5 days (October 20-24), the odds favor above-median precipitation throughout much of the middle third of the U.S., in the Northwest and Southeast, and southern Alaska, with a tilt toward sub-median precipitation in California, along the mid-Atlantic and New England coasts, and western Alaska. Above-normal temperatures are favored in much of the lower 48 States and southern Alaska, with only near-normal readings expected in northern Alaska, the Carolinas, and New Mexico.

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