Spring Arrives With Meteorologists' Grim Forecast for California Water Supply
SAN FRANCISCO (CNN) -- Saturday marks the first day of astronomical spring and the outlook is grim for the western portion of the country, where drought conditions will persist.
"Drier conditions in the Southwest U.S. associated with La Niña and the failed 2020 summer monsoon have been contributing factors to the development and intensification of what represents the most significant U.S. spring drought since 2013," according to the National Oceanic and Atmospheric Administration (NOAA).
Dry weather is expected to linger into the spring, with below average precipitation forecast across much of the West. This will likely make the drought situation even worse.
One of the contributing factors to the western drought has been lack of snowfall. The greatest area of snow drought expansion has been in the Sierra Nevada where no large storms have occurred since the strong atmospheric river in late January. This has left almost all of the Sierra Nevada weather stations below the 30th percentile of snow water equivalent and a few locations in the southern Sierra are even below the 10th percentile.
But what is bad for some can be good for others in terms of snowpack. It's the ultimate dichotomy.
That's because unlike in some previous years, that lack of snowmelt means flooding will be less severe across the Plains and Midwest but it also means lack of necessary water for the western states that rely on it to keep drought conditions in check.
Drought conditions to worsen as we head into peak fire season
Drought continues to plague about 44 percent of the contiguous U.S., mostly in the western states, and the spring outlook expects that drought to persist.
Currently, the most severe drought conditions are across the western U.S., with 20 percent of the region in exceptional drought. This is the worst category on the National Drought Mitigation Center's scale. Nearly 90 percent of the region overall is at least abnormally dry and these drought conditions could worsen.
Going into summer with dry conditions is also worrisome since that is when wildfire season begins to ramp up.
"With warmer spring temperatures forecast and the drought deepening, fire season could start earlier in some places and be more severe this year," says Chad Myers, a CNN meteorologist.
Some major cities in the West have experienced record dry streaks within the past year and this persistent drought has had an effect on the agriculture industry.
The National Integrated Drought Information System (NIDIS) -- a division of NOAA -- lists crops and livestock affected by drought. As of this week, more than 150 million acres of crops are under drought conditions in the U.S. The drought's impact on agriculture can be connected to higher prices due to crop losses.
In other portions of the U.S., a drought may begin: "Warmer-than-average temperatures this spring and low soil moisture will allow drought conditions to develop and expand in the southern and central Great Plains as well as southern Florida," according to NOAA.
Meanwhile in the Northeast and mid-Atlantic regions, a wetter than normal spring is forecast. Some areas in this part of the country are currently experiencing dry conditions and, in some cases, a moderate drought but that will give way in the Northeast to a wet spring..
NOAA anticipates any drought in the Northeast to end thanks to the expected weather patterns this spring.
There is a bright side but not for everyone
However, drought isn't always about rain. Snowpack, again, is a factor.
"In the West, winter snowpack can be more effective at relieving drought than summer thunderstorms. The snowpack melts slowly and doesn't just run off the parched soil," says Myers.
As of this week, nearly 70 percent of western contiguous U.S. weather stations are below median for snow water equivalent.
Snow drought conditions remain focused over the southwestern U.S., especially across the Sierra Nevada and Rocky Mountains. In these areas, nearly one-third of snow telemetry stations are below the 30th percentile snow water equivalent.
Lack of strong storms in the Sierra Nevada left states like California, Nevada and Arizona at a huge disadvantage going into the summer dry season.
While snow drought may be low across the Colorado River headwaters, they have improved along the Colorado and Wyoming Front Range since the beginning of the month.
Last week's record snow in the Rockies helped boost overall snowpack. In fact, for the Upper Rio Grande most basins received a 15 percent boost in snow water equivalent.
While that particular basin saw enough of a surge to reach near average levels, "water supply forecasts still remain below average," the West Gulf River Forecast Center says.
For the first time since 2018, NOAA hydrologists are forecasting limited widespread flooding this spring. More importantly, there are no areas greater than a 50 percent chance of major flooding.
"A reduced flood risk exists for the majority of the Greater Mississippi River Basin, Red River of the North, and Souris Basins, primarily due to abnormally dry conditions, ongoing drought, and a lack of snowpack and associated water equivalent."
Even compared to last year the flood threat for much of the Midwest and Plains regions is lower, which is welcome news for people in those areas of the country. The last two years have brought increased flood threats to much of the Mississippi and Missouri River basins, so the drier conditions that are forecast this year are actually considered a positive compared to what's happening to the western US states.
Spring could feel more like summer
Temperatures this spring during the months of April, May and June are forecast to be warmer than normal for the large majority of the country.
NOAA forecasts all of the contiguous U.S. to experience temperatures above average overall with the exception of the Northwest. Western Washington is expected to feel below average temperatures while the rest of the region has an equal chance of above, below or near-normal conditions.
The greatest chance for above average temperatures is across the interior Southwest, which is also dealing with exceptional drought conditions.
Past springs (in months April through June) have also been on the warm side. The last time the U.S. experienced below-average temperatures during this time period was more than a decade ago in 2008.
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