California and National Drought Summary for January 2, 2018 Summary January 4, 2018 – During the 7-day period (ending Tuesday morning), bitterly cold, mostly dry weather prevailed across the nation.
Farther south, Moderate Drought (D1) was expanded from northeastern Pennsylvania into central Maryland; 90-day precipitation in these locales has totaled less than 70 percent of normal, and groundwater levels continued to drop (25th percentile or lower in many reporting locations).
Rainfall over the past 60 days averaged less than 50 percent of normal from central Alabama into central and northern Virginia, while 90-day totals have totaled 30 to 60 percent of normal from central North Carolina up to the Potomac River Basin.
Moderate to Severe Drought (D1 and D2) were reintroduced to locales in Louisiana, Mississippi, and Arkansas where 90-day rainfall was 60 percent of normal or less and subsequent streamflows — which exhibited short-term recovery after late-December rain — resumed a sharp downward trend.
Midwest Bitter cold weather prevailed with a moderate to deep snowpack covering all but southern portions of the region.
There were no changes made to the drought depiction in central and eastern portions of the region, while reductions in Abnormal Dryness, Moderate Drought, and Severe Drought (D0-D2) were made in northwestern Montana to account for the favorable start to the Water Year and the easing of long-term moisture deficits; 12-month precipitation climbed to near-normal levels in western Montana, but was still less than 50 percent of normal in the lingering Extreme Drought (D3) areas.
West Drought intensified in the Four Corners, while heavy snow brought welcomed drought relief to northeastern portions of the region.
Across Montana, Abnormal Dryness to Severe Drought were trimmed along the Canadian border to account for the favorable start to the Water Year and subsequent easing of long-term moisture deficits; 12-month precipitation climbed to near-normal levels in western Montana, but was still less than 50 percent of normal in the lingering Extreme Drought (D3) areas.
Severe Drought (D2) was expanded over large portions of the Four Corners region, coincident with much-below-normal precipitation totals over the past 6 months (30-65 percent of normal).
Elsewhere, periods of rain and snow will affect northern California and the Northwest, while dry weather prevails across the central and southern Plains.