It's now the final month of meteorological winter. The days are getting longer and average high temperatures are now beginning to climb. Average highs across New England are about 5-7 degrees warmer by the end of the month than the beginning. This month, however, may see cooler weather in the second half. Here's the big picture for this month:
TEMPERATURES
February will start off with an Omega-style blocking pattern in place. A ridge in the center of the country will remain in place through this weekend into early next week. New England will be on the edge between this ridge and a trough of low pressure near the Canadian Maritimes. This will keep the building milder air over the interior of the United States from reaching New England.
With New England being on the edge, this will likely lead to a stretch of seasonable temperatures for early February, with the warmth remaining to our west and an arctic shot of cold centered to our east.
Heading deeper into next week, the ridge over the center of the country is looking to begin to break down as it slides eastward. This should allow the more mild air to begin to spread eastward. At this point, it doesn't look like a major warm-up will be coming to New England next week, but there is some confidence in above average temperatures by the middle to late next week and potentially lasting longer.
Heading toward the middle of the month, the pattern begins to shift. After starting the month well into the positive range, North Atlantic Oscillation (NAO) is expected to begin to weaken. Arctic Oscillation (AO) is also expected to trend toward a negative phase after starting the month strongly positive. A weaker/negative phase of both these oscillations would support more cold air intrusions getting into New England.
As always, it's important to remember that a positive phase of NAO or AO doesn't automatically mean it will be warm and a negative phase of these oscillations doesn't automatically mean cooler weather. If this was true, long-range forecasting would be much easier. These positive/negative phases just support those things happening.
Also heading toward the middle of the month, a persistent trough in the western United States will begin to weaken and shift eastward. All of this points toward a potential cooler, more winter-like weather for the second half of the month.
Overall, we're predicting a near seasonable February with a generally more mild first half followed by a generally cooler second half. We're thinking these shifts between warmer and cooler weather will result in an average month as a whole.
PRECIPITATION
After being dominated by low pressure for the past couple weeks, high pressure will be building into New England. This will bring New England a much needed break from consistently cloudy weather. Much sunnier and calm weather will arrive in New England this weekend.
One area to watch heading into next week will be the southeast United States. An active southern jet will keep the south unsettled. Around the middle of next week, an area of low pressure will emerge off the southeast coast. As of now, this system looks to get suppressed well south of New England as high pressure continues over New England, but a wide range of potential tracks still exist at this time range. Overall, the start of February is looking very calm.
The month as a whole may end up being a bit calmer than normal as below average precipitation is expected through much of the month. The one issue with February is that this is the month that the region typically sees its largest snowstorms. It will only take one strong nor'easter to throw a wrench in this below-average precipitation forecast.
Overall, the precipitation forecast (and temperature forecast for that matter) is very indicative of a strong El-Nino winter. Strong El-Ninos favor a drier north and more active, unsettled south. The one month outlook from the Climate Prediction Center is nearly the definition of what's expected during a strong El-Nino.
LOOKING BACK
January played out pretty much exactly as expected in our January weather outlook. We titled the outlook "stormy times ahead" as an active pattern was likely to bring New England above average precipitation. New England saw storms on January 6-7; January 9-10; January 13; January 16; January 23-24; January 25-26 and January 28-29. We also stated that due to expected temperatures, New England may see more messy mix type storms and just about every precipitation type got their time to shine during at least one of these storms.
We also predicted a slightly above average month temperature-wise. Boston saw around 13 days above average and around 8 days below average. Other cities around New England saw around these same numbers. A cold snap in the middle of the month lasted 5-7 days depending on exactly where you are in New England. This cold snap hung on longer than we were expecting a cold snap to be able to in January.
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