Publisher’s Note: A version of this article originally appeared in the weekly weather newsletter, published every Monday. You can sign up here to receive these every week and during heavy storms.
Spring starts on Tuesday, but if you google the word spring, it will answer March 20th.
You did NOT go through a time warp; Tuesday is not March 20th. It’s March 1st. Google is not wrong, astronomical spring (based on the earth’s rotation around the sun) is at the vernal or vernal equinox.
But in the meteorological world, spring begins on March 1st.
“Meteorologists and climatologists divide the seasons into three-month groups based on the annual temperature cycle and our calendar,” the National Oceanic and Atmospheric Administration (NOAA) explained.
The groupings make it much easier to calculate seasonal stats from monthly stats.
One thing you may not know is that what happens in the winter months can, to some extent, impact what happens in the spring.
Does a dry winter lead to a dry spring? Or does a cold and snowy winter lead to a cooler spring?
There’s no doubt that this winter has been brutal for some. In the north of the country, an already cold region, temperatures were well below seasonal norms.
As I write this and look ahead to the week ahead, things are looking promising if warmer temperatures are desired. But so much goes into forecasting, especially when you’re forecasting three months ahead.
John Gottschalck is the director of operational forecasting at NOAA’s Climate Prediction Center (CPC). He is one of the experts who will make the long-term forecast and to make a forecast you have to look into the past.
He noted that one of the things that struck him during the winter was the unrelenting rain that fell over the middle Mississippi Valley, causing flooding.
Rain fell in the West early in the season but was shut off when California was expected to reach its peak rainfall, causing the region to finish the season well below normal.
Gottschalck acknowledged how wet or dry a region is at the moment could impact the next three months.
He explained that a region’s soil moisture can affect temperatures over the longer term, meaning that if an area is very wet, its temperatures could get slightly cooler. On the other hand, if an area is exceptionally dry, its temperatures may be slightly above normal.
“A lot of surface water, whether it’s from flooding or just higher rivers or just above-normal soil moisture, can tend to keep temperatures below normal or lower than normal,” Gottschalck outlines. “Certain areas that have been fairly dry, for example, may rise a little if temperatures are above normal.”
Case in point: California. We were all optimistic at the start of the season given all the rain they received in December and then nothing proving how quickly things can change for better or for worse.
“We’ve had all this excitement about the drought improving and there was definitely a lot out west, early December,” Gottschalck said. “But right now, if you look at the 90-day normal departures, Northern California and Oregon have been significantly below normal for the past two months, so that’s actually trumping.”
Going forward, California could pick up where it left off with a continuation of a drier and warmer pattern, as could Texas.
“Texas had one of the hottest Decembers on record,” Gottschalck reported. “These conditions will play some role in the prospects further as this feedback may lead to warmer temperatures.”
Note the continuation of the La Niña pattern, a phenomenon in which cooler than normal sea surface temperatures occur in the Pacific Ocean near the equator. It is affecting weather around the world, including an increase in Atlantic hurricanes.
Learn more about La Nina
La Niña influenced this winter, including early-season rains in the west, to be colder than normal in the north and warmer than normal in the south.
“The La Niña pattern often creates cold in the Pacific Northwest and along the West Coast and even on the northern plains, and this can last well into March,” Gottschalck pointed out. “If that continues into March, it could be a colder start, more like La Niña in early spring.”
Gottschalck added that we will move away from a La Niña pattern later in the spring.
“As you enter more neutral conditions, you lose some of your climate reliability in terms of forecasting,” Gottschalck explained.
“We’re starting to focus a bit on where we have deficits and/or excesses in snow cover and snow water equivalent and soil moisture in the spring because these can feed back into air temperature,” Gottschalck pointed out.
Places like the Ohio Valley and Tennessee Valley will likely remain on the cooler side, in part because of the amount of rain they’ve received.
And these prospects are known to relate to the entire season. During the season there are ups and downs, rainy periods and dry periods.
But can I just say one more time: Hooray! Spring is just around the corner, no matter when spring “officially” begins!
Ironically, on the first day of meteorological spring, March 1st, weather geeks (like me) will rejoice! NOAA will launch a new weather satellite called GOES-18.
The satellite will sit more than 22,000 miles above the Earth, tracking the western United States, Alaska, Hawaii, Mexico, Central America and the Pacific Ocean.
It will have a wide range of instruments and will be able to send back ultra-high resolution images that will greatly improve weather forecasts and the computer models we rely on for forecasts.
“The observations from these satellites are even more critical now that the US is experiencing a record number of billion-dollar disasters,” Pam Sullivan, director of NOAA’s GOES-R program, said during a news conference. “Compared to the previous generation, GOES-R satellites provide 60x more imagery and feature a new flash camera to track severe storms that produce tornadoes and damaging winds.”
We will be able to see the evolution of these storms in the Pacific Ocean and track them to the United States.
Like West Coast atmospheric flow events, where the West receives most of its annual precipitation. However, they can also cause deadly floods and landslides. Being able to better predict where these systems will be put in place will protect life and property in ways we have never seen before.
- Years ago, CNN meteorologist Judson Jones, who writes the weather newsletter with me, visited GOES-R and GOES-S before wrapping them up. You can read more about it here.
- Our science writer Ashley Strickland and author of our amazing science newsletter called Wonder Theory is closely following the launch of GOES-T. You can read more about her here.
The first images of GOES-18 won’t be available until next summer, which is a bit of a shame as they would be really useful across the West this week.
A Level 4 of 5 “extreme” atmospheric flow hits the Pacific Northwest this week, threatening flooding and avalanches. Flood monitors are in place for more than five million people in Idaho, Oregon and Washington, including Seattle.
The rain will last for several days. A combination of warmer temperatures will cause heavy rain in the mountains that currently have snow. This could result in rapid melting and runoff of water, which could result in dangerous flooding and wet avalanches.
“Wet” avalanches typically occur when warm air, sun or rain causes water to drain into the snowpack, which in turn reduces the snow’s strength.
The Northwest Avalanche Center issued a strong warning as the avalanche danger has increased exponentially.
“Avalanches triggered today could be large enough to bury you or kill you. This will not be the day to try to tiptoe around danger.”
Read more here.