Little or no precipitation recorded in High Plains
With high pressure anchored over the eastern Pacific Ocean, storm systems bypassed California, Nevada, Arizona, and Utah, instead tracking either northward into the Pacific Northwest or southward across Baja California and into the southern Rockies. Once they reached the nation’s mid-section, ample Gulf moisture was incorporated into the storm systems, generating widespread showers and thunderstorms in the South and Southeast, along with mixed or frozen precipitation in more northern locales.
The week’s heaviest precipitation (1 to 4 inches) fell on western sections of Washington and Oregon, parts of the Rockies, and in the southern Great Plains, lower Mississippi, Tennessee, and Ohio Valleys, Southeast, and Appalachians. Weekly temperatures averaged below normal in Alaska and across much of the North-Central states as Arctic air brought sub-zero readings to most of the Midwest Thursday and Friday. In contrast, above-normal readings encompassed the Southeast, mid-Atlantic, and portions of the Far West.
South
Heavy rains (2 to 5 inches) fell from central Texas northeastward into southwestern Arkansas, across northern Louisiana, and from west-central Mississippi northeastward into central Tennessee. Light to moderate amounts (0.5 to 2 inches) were reported in northern and eastern Texas, eastern Oklahoma, and the remainder of Arkansas, Louisiana, Mississippi, and Tennessee. Little or no precipitation occurred in western portions of Texas and Oklahoma, and across southern and southeastern Texas. Weekly temperatures were seasonable in western and northern sections of the South, and above-normal along the central Gulf Coast.
With the heavy rain that fell across central and northeastern Texas, a broad 1-category improvement was made, including some 2-category reductions (D2 to D0; D1 to nothing) in northeastern Texas where the amounts were the greatest. Elsewhere, some of the D0 and D1 was erased in northern Texas and southwest Oklahoma that incorporated precipitation over the past 2-week period; the D0 in southwest Arkansas was removed; and some D0 was alleviated in Louisiana and southern Mississippi where the totals exceeded an inch. In contrast, very dry weather the past 30- to 60-days in southern Texas, combined with above-normal temperatures, warranted a broad 1-category degradation in many southern and southeastern sections of the state. Deficits at 30-days reached 0.5 to 1.5 inches and 1.5-3 inches in southern and southeastern portions, and at 60-days, shortages were 1 to 2 inches and 2 to 4 inches, respectively. D3 was added or expanded where the short- and medium-range tools (3-, 6-, and 9-months) were the driest, along with corresponding to low values (less than tenth percentile) on the USGS average stream flows. D0 was also expanded into extreme southwestern Louisiana where little or no rain fell and short-term deficiencies grew.
Midwest
Similar to the Northeast, short-term (30-days) precipitation deficits existed, but near to surplus precipitation is common across the Midwest at longer time periods (2 months and longer), thus no drought or D0 was depicted. In addition, snow covered much of the upper Midwest and Great Lakes region, and with subnormal temperatures this week, the ground and smaller rivers were frozen in many northern locations. This region could actually use some dryness and warmth to get the fields primed for spring preparation and planting.
High Plains
Little or no precipitation was recorded across the northern and central Plains, although scattered light totals occurred in parts of the northern and central Rockies. The past 30 days have been drier than normal, but January and February precipitation climatologies are normally dry, and temperatures have been below normal the past 2 weeks. From 3 months and longer, however, wet conditions prevailed throughout much of the northern and central Plains, and with low temperatures, the non-growing season, and frozen and snow-covered ground in the north, drought and D0 was limited to southern areas (Kansas and Colorado), along with smaller D0 areas in northern Wyoming and western Montana.
In south-central Kansas, light precipitation (0.25 to 1 inch) was enough to ease drought and dryness, while decent snowfall in central Colorado brought most indices close to normal, thus eliminating D0 in Lake County. In western Wyoming’s Teton County, 0.5 ti 2 inches of precipitation boosted SNOTEL WYTD basin average precipitation and SWC to near-normal (97%) and above-normal (112%) levels, respectively, eliminating the D0 there. Light precipitation in northern Wyoming’s Big Horn County also decreased D0 along its eastern edges. In contrast, D0 expanded somewhat in western Montana as 30- and 60-day indices were very low (dry), but WYTD values were close to normal. Fortunately, SNOTEL WYTD basin average SWC has remained above normal.