Northern California typically experiences a wet season, October through May, and a dry season May through September. Last year's water year, October 2019 through September 2020, was one of the driest on records.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS STO wrote it up.
Northern California typically experiences a wet season, October through May, and a dry season May through September. Last year's water year, October 2019 through September 2020, was one of the driest on records. This likely contributed to the U.S. Drought Monitor's decision to place portions of interior northern California into extreme drought on September 29, 2020. Portions of Shasta, Tehama, Butte, Glenn, Colusa, Yolo, Solano, Yuba, Nevada, and Sacramento counties remain placed extreme drought. The rest of interior northern California was placed into severe drought (D2) on December 8; however, the state of California has not announced that these locations are in drought.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Sacramento, CA wrote its last area forecast discussion before the first event at Jan 31, 10:30 PM PST, 1 hour 30 minutes earlier.
Area Forecast Discussion National Weather Service Sacramento CA 1030 PM PST Sun Jan 31 2021 .SYNOPSIS... Light to moderate showers possible today across the northern Sacramento Valley and northern mountains. A winter storm is forecast to impact NorCal late Monday into Tuesday night. Dry weather should return by Thursday and continue through the weekend with periods of increased north to east winds. && .DISCUSSION... The Evening Update: Some WAA precip is rapidly moving Nwd over the Nrn portion of the CWA including the Nrn Sac Vly where RDD could pick up some light QPF by 11 pm LT. This band will move through by 1 am or so over Shasta Co. The frontal band is along the N coast and will nudge inland on Mon as the upper trof axis (mentioned below) barely moves to 130W. Energy moving into the base of the trof will eventually bifurcate or split into 2 low pressure systems, one heading well to the SW of Norcal and the parent low moving into the Pac NW Tue/Wed. It is this parent low that may keep some showers over portions of Norcal into Wed as it deepens a trof over NV into the afternoon. Best estimate of the frontal band is that is should move into the NW quarter of our CWA Tue evening, then moving into the 80/50 corridor Tue morning. It should linger over the Sierra into Tue evening, possibly longer into Wed morning for areas S of 50 if one leans to the GFS solution. NAM 3km this evening indicated the chance of higher REF Tue afternoon over the Nrn Sac Vly/NE foothills with nice veering profiles, but limited mid level CAA. Can't rule out a possible T- storm there, but chances seem low as the CAPE is thin and capped around 10-11 kft. .Previous Discussion... A large upper level trough continues deepening over the eastern Pacific today, clearly visible on satellite imagery. Moisture plume remains fairly stable today ranging over the northwestern California coast up into the Pacific Northwest. Light showers continue over the Coastal Range, southern Cascades, and northern Sacramento Valley this afternoon into tonight. The next winter storm is still slated to impact interior Northern California tomorrow through early Wednesday. Ensemble guidance continues to indicate the trough will begin moving inland tomorrow with the main dynamics moving into the CWA late tomorrow. General timing has not changed much since the previous forecast, though slight timing inconsistencies of the onset and southern extent of the precipitation remain between the GEFS and Euro ENS. Overall, still expecting the main band of precipitation to begin pushing into the northern counties tomorrow afternoon, slowing spreading southwest into the Sierra and Central Valley by tomorrow evening. The heaviest precipitation is expected late tomorrow night through Tuesday night. Snow levels are now beginning higher with most snowfall expected above 5000 to 6000 feet. Light snow may be possible down to 4500 feet behind the frontal passage Tuesday. Precipitation amounts do continue to slightly decrease, though. QPF amounts are now 0.5 to 1.25 inches in the Valley with up to 1.5 to 2 inches in the foothills and mountains below snow level. In the mountains, 8 inches to 2 feet of snow are forecast with locally up to 3 feet around Lassen NP only. Gusty winds are also expected Monday afternoon through Tuesday. Gusts up to 20 to 30 mph are possible in the Valley and up to 40 to 50 mph in the mountains, locally higher in wind prone areas. Precipitation is expected to begin decreasing overnight Tuesday through early Wednesday as the trough continues to move southwest. Mountain showers could linger through Wednesday morning. The Winter Storm Watch remains in effect timing unchanged from late Monday night through early Wednesday morning. -HEC && .EXTENDED DISCUSSION (Thursday THROUGH Sunday)... Models are in good agreement the Eastern Pacific Ridge will build into next weekend with the ridge axis slowly moving towards the West Coast. Models continue to trend a low pressure system eastward that is expected to drop into the great basin Friday. The latest forecast guidance indicates this will be far enough into our east that no notable impacts are expected for Northern California. High pressure over the region will yield quiet and dry weather for Northern California with generally seasonable temperatures. Periodically breezy north to east winds are possible. && .AVIATION... VFR conditions expected with MVFR possible due to passing showers KRDD and KRBL. Winds generally under 15 kts. Southerly Gusts increase after 18 UTC Monday. Surface gusts 10-20 kts expected for Valley terminals. && .STO WATCHES/WARNINGS/ADVISORIES... Winter Storm Watch from late Monday night through late Tuesday night for West Slope Northern Sierra Nevada-Western Plumas County/Lassen Park. &&
5 drought. Local standard time, as filed.
For the month of February, the U.S. Drought Monitor kept the majority of zone 13, which covers Shasta County, in extreme drought (D3). The California Department of Water Resources continues the water allocation of 10% for the State Water Project that started on December 1st.
For the month of February, the U.S. Drought Monitor kept all of zone 15, portions of Shasta and Tehama counties, into extreme drought (D3).They also noted on this month's call the following impacts for the Sacramento Valley: low groundwater levels, dry stock pond, and poor range-land and pasture conditions. Some ranchers have even stated they've started selling livestock. Additionally, the California Department of Water Resources continues the water allocation of 10% for the State Water Project that started on December 1st.
For the month of February, the U.S. Drought Monitor kept most of Glenn and Colusa, and Sutter counties along with the western portions of Butte and Yuba counties in extreme drought (D3). They also noted on this month's call the following impacts for the Sacramento Valley: low groundwater levels, dry stock pond, and poor range-land and pasture conditions. Some ranchers have even stated they've started selling livestock. Additionally, the California Department of Water Resources continues the water allocation of 10% for the State Water Project that started on December 1st.
For the month of February, the U.S. Drought Monitor kept all of Yolo County, and portions of Sacramento, Sutter, Solano counties in extreme drought (D3). They also noted on this month's call the following impacts for the Sacramento Valley: low groundwater levels, dry stock pond, and poor range-land and pasture conditions. Some ranchers have even stated they've started selling livestock. Additionally, the California Department of Water Resources continues the water allocation of 10% for the State Water Project that started on December 1st.
For the month of February, the U.S. Drought Monitor kept all of zone 63, which covers western Tehama, Glenn, and Colusa counties in extreme drought (D3). They also noted on this month's call the following impacts for the Sacramento Valley: low groundwater levels, dry stock pond, and poor range-land and pasture conditions. Some ranchers have even stated they've started selling livestock. Additionally, the California Department of Water Resources continues the water allocation of 10% for the State Water Project that started on December 1st.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2021Every state in 2021This day in weather historyWarnings in California, February 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 945464, 945465, 945466, 945467, 945468.