2022 Northeast spring outlook part one

 

It is that time of year for the spring flood outlook.

This is the first of two scheduled outlooks for the Northeast and Middle Atlantic region.

Meteorological spring runs from March 1 through the end of May.

October was very warm, whereas November was cold with shots of snow. This pattern carried into the winter.

Winter 2021-2022:

Temperatures were significantly above average across the region through the month of December. Generally, the regional temperatures ranked among the top-five Decembers since records began in 1895. December was also generally a drier-than-average month for the Northeast.

 January started off unseasonably mild. January ended up being cold and snowy and for parts of the region it was one of the snowiest Januarys on record. January was much colder than the 1991-2020 thirty-year average. But while January 2022 was a cold month, generally temperatures are not getting as cold as they once did 30-40 years ago.

So far February has been volatile. With the temperature pendulum making wide swings back and forth.  Based on how I think the pattern will evolve, February will likely end up slightly below average as far as overall temperatures.

The overall pattern this winter has seen a mostly positive North Atlantic Oscillation (NAO) and arctic oscillation (AO). In the Pacific La Nina conditions in the equatorial Pacific. Madden-Julian Oscillation (MJO) is in Phase 3 this is a cold phase for February.  The MJO went into the cold phase in December before retreating into the null phase, where it had no real influence, but pattern remembered the earlier influence leading to the cold January. The Eastern Pacific Oscillation and Western Pacific Oscillation have been the dominate teleconnections this winter. They are the major reasons we’ve seen the back-and-forth temperature pattern every 4 to 6 weeks.   Western and northern parts of the region and the Middle Atlantic including the I-95 corridor with the exception of Philadelphia have seen near average to above average snowfall to date. While a large part of eastern Pennsylvania southeast New York State including the NYS Capital District into western and central New England have seen below average to well below average snowfall to date. The reason for the snowfall disparity is due to the timing of the elements and storm tracks.

Spring 2022 thoughts:

The Climate Prediction Center (CPC) just released their latest 3-month climate outlook for the United States.

Temperature forecast March-May: Climate Prediction Center

 

The CPC is showing above average temperatures for the Northeast and Middle Atlantic region.

 

Precipitation forecast March-May: Climate Prediction Center

 

The CPC is showing above average precipitation for western New York State and western Pennsylvania, with near average for the rest of the Northeast and Middle Atlantic region.

 

La Nina:

 

The 2021-2022 La Nina has been classified as a weak La Nina with sea surface temperatures only slightly below normal. The La Nina in 2020-2021 was a moderate event. As is typical of weak La Nina’s this one made for a chaotic rollercoaster ride this winter. During a weak La Nina the region has a slightly better chance for above normal snowfall and slightly above normal temperatures over the entire winter season.

Temperatures were significantly above average across the region through the month of December. Generally, the regional temperatures ranked among the top-five Decembers since records began in 1895. December was also generally a drier-than-average month for the Northeast.

 January started off unseasonably mild. January ended up being cold and snowy and for parts of the region it was one of the snowiest Januarys on record. January was much colder than the 1991-2020 thirty-year average. But January 2022 was an illustration that even in a cold winter month these days, it's on average not getting as cold as it once did.

In a La Nina wintertime pattern, the polar jet stream tends to dip farther south across the continental United States. Resulting a better chance for cold and snow across northern parts of the region. But the jet stream position does vary. La Nina is expected to stick around for at least a little while longer, with the transition back to neutral conditions most likely not taking place until early this Summer. One thing we have to keep in mind, is that the Great Lakes also have a lot of influence on the Region.  

As I said above, we’re in a 2^nd year La Nina. There are some signs that show the possibility for a return to La Nina conditions for next Fall into Winter 2022-2023.  That could allow for another active Atlantic hurricane season, The Atlantic hurricane season does not officially start until June 1, but a storm could form before the official season gets underway. There is also a chance for above average tornado activity this year.  

Sudden Stratospheric Warming Event:

Here is a look at the stratospheric temperature forecast from NOAA. It shows the sudden stratospheric warming event unfolding and bringing the Great Lakes and East plenty of cold air as we head into March.

 

 

Madden-Julian Oscillation (MJO):

The MJO phase diagram illustrates the progression of the MJO through different phases, which generally coincide with locations along the equator around the globe. RMM1 and RMM2 are mathematical methods that combine cloud amount and winds at upper and lower levels of the atmosphere to provide a measure of the strength and location of the MJO. When the index is within the center circle the MJO is considered weak, meaning it has little to no influence.  

From here the MJO looks to go into Phase 4, this is a cold phase for March. The American GFS model takes the MJO into phase 5 and maybe phase 6. But the European ECMWF, Japanese JMA, United Kingdom UKMET and most of the others keep in phase 3 or 4 than move it into the center circle (Null). So I don’t think the GFS has a good handle on the pattern.  This time of year, phases 3,4, and 5 are cold phases for March and April. As we saw in the end of December, the atmospheric pattern could end up remembering the earlier MJO input. If this does happen March would be colder than average overall.

  

The other Pacific Teleconnections:

 

The Pacific has been in the driver’s seat this winter. It has overridden the Atlantic Oscillation and North Atlantic Oscillation this winter. There are several reasons for that, not the least of which is warming global temperatures.

The EPO:

 

The WPO:

 

The Eastern Pacific Oscillation and Western Pacific Oscillation have been the dominate teleconnections this winter. These are going to take a sharp dive into the negative phase.  That is a strong signal for a cold March. 

The AO:

 

The NAO:

 

The AO and NAO have been overall positive so far this winter. As I said, the EPO and WPO have been overriding the AO and NAO. But the AO and NAO are looking to go negative; with all these teleconnections cooperating with each other March into April could be very cold indeed.  

 

All of this means that March into April will surely be colder than average overall.  With the cold will come snow opportunities, how those chances work out and for who, will depend on the exact storm tracks. But historically March is more than capable of delivering major snowstorms. So we will see.

 

The spring flood risk:

First taking a look back at how much precipitation fell across the region before the ground froze. The map from the Northeast Regional Climate Center (NRCC) shows the accumulated precipitation (in) departure based on the 20^th century average. The map shows that Central into Eastern New York State saw slightly above average precipitation for Oct through December, with most of the rest of the region seeing around average to slightly below, while Maryland, Delaware and the Middle Atlantic region saw below average precipitation.

 

The maps from NRCC shows that much of the region saw below average precipitations for January.  

 

The maps from WeatherBELL Analytics showing data from the Climate Prediction Center show how much of the region is below average for precipitation over the few months.

The recent milder temperatures across the region have resulting in snow loss

The map from the National Operational Hydrologic Remote Sensing Center shows across most of northern New York State and northern New England along with the higher terrain in Central New England have a snowpack with 4 to near 14 inches of water equivalent.  

 

As a result of all of this any spring flooding will be due to spring precipitation, rather than from fall and winter conditions. It also means we will have a possible drought issue this Spring.

Any spring flooding will be due to spring precipitation than from fall and winter conditions.

 Conclusion:

While Spring 2022 will likely see overall temperatures average to slightly warmer than average. I think the CPC is overdoing the overall warmth.  March going into April is looking to be cold. The 2^nd half of April and May will likely see spring warmth. But I don’t see Spring having well above average temperatures overall.

For the rest of winter, I think the pattern will remain active. So, we will be seeing more snow/mix and rain.  But I think the amount of precipitation that makes it into the ground is going to be average to below average.  So later in the Spring going into Summer could see drought conditions become a problem.

 

That’s the end of part one. I will be releasing part two during the first part of March. Part two will go into more detail on temperature and precipitation patterns.