National Weather Service United States Department of Commerce

Heavy Rain and Mountain Snow Lingers in California; Winter Storm Impacting the Great Lakes and Northeast U.S.

An atmospheric river will wind down through today across California with lingering heavy rainfall, heavy mountain snow, and gusty winds. A wintry mix of freezing rain, sleet, and snow will cause hazardous travel conditions for the Great Lakes into the northern Mid-Atlantic and southern New England today through Saturday morning. Areas of tree damage and power outages are possible. Read More >

 

  Drought Severity Classifications

 

Ranges

Category

Description

Possible Impacts

Palmer Drought Index

CPC Soil
Moisture Model
(Percentiles)

USGS Weekly Streamflow
(Percentiles)

Standardized Precipitation Index (SPI)

Objective Short and Long-term Drought Indicator Blends (Percentiles)

D0

Abnormally
Dry

Going into drought: short-term dryness slowing planting, growth of crops or pastures. Coming out of drought: some lingering water deficits;  pastures or crops not fully recovered

-1.0 to -1.9

21-30

21-30

-0.5 to -0.7

21-30

D1

Moderate Drought

Some damage to crops, pastures; streams, reservoirs, or wells low, some water shortages developing or imminent; voluntary water-use restrictions requested

-2.0 to -2.9

11-20

11-20

-0.8 to -1.2

11-20

D2

Severe
Drought

Crop or pasture losses likely;  water shortages common; water restrictions imposed

-3.0 to -3.9

6-10

6-10

-1.3 to -1.5

6-10

D3

Extreme Drought

Major crop/pasture losses;  widespread water shortages or restrictions

-4.0 to -4.9

3-5

3-5

-1.6 to -1.9

3-5

D4

Exceptional Drought

Exceptional and widespread crop/pasture losses; shortages of water in reservoirs, streams, and wells creating water emergencies

-5.0 or less

0-2

0-2

-2.0 or less

0-2