After quite a long break from blogging, I've finally come back (I'll admit, I've been busy with several things), and I'll probably be blogging much more often. The topic of this post will be rather grim (in regards to the end of the winter, as well as the immediate long-range forecast).
First, let's have a recap of the winter so far. On December 1, 2012, the vast majority of the United States began with increasingly above normal temperatures. In fact, many areas were breaching records that had not been breached in over 30 years. Widespread 60's and even 70's came as far north as Indianapolis in the Ohio Valley. Although warmth was experienced last year, this season's warmth has been mitigated by intense cyclones, and strong cold fronts from the northwest. A strong cyclone plowed through the Upper Midwest, bringing blizzard conditions to the Upper Midwest, while bringing chilly air into the East. While it was not substantial, as some have been in the past, it was quite a reversal from the record warmth of the beginning of December. As December progressed, it became cooler and cooler (as is expected), with more frequent storm systems, and RAIN (ugh). Yet, we had an exceedingly lack of accumulating snowfall. In fact, until about December 20th or the 21st, no more than 0.1 inches of snow was recorded at both South Bend AND Fort Wayne International Airports. Even so, an abrupt (more of a gradual pattern response though) pattern change commenced after a large cyclone traversed the Great Lakes in the days leading up to Christmas, bringing heavy rain to the Ohio Valley and East (once again). The cold front swept through, bringing high winds and much-needed colder air to the region. By that time, the threat of a major storm system was on the horizon, and it was predicted that the storm would mainly impact the Interior regions of the Northeast, largely sparing the coastal areas. Over the next few days leading up to Christmas, model forecasts began a quick reversed trend west with the cyclone, which shifted the snowstorm threat to the Ohio Valley through the Interior Northeast and New England. By Christmas Day, not only had a heavy snowstorm commenced over the Southern Plains, but a deep low pressure system was causing the development of widespread heavy, and sometimes severe thunderstorms across the Deep South. By Christmas Night, the low pressure system was moving northeast bringing widespread heavy snow from Arkansas to Indiana/Ohio, icing to Kentucky and parts of Tennessee, as well as heavy rain and thunderstorms to parts of the East. Heavy snow continued to spread northward and eastward, producing a large swath of 6-12" inches of snow. December ended with very cold weather across the nation, and record snow cover as well.
January began very cold across most of the United States, with temperatures well below normal over a large area. Snow cover was also well above normal as several weak, southern stream systems spread snow across the Midwest, Ohio Valley and Northeastern States. Lake effect snow continued as well from Lake Michigan, to Lake Ontario. By early to mid January, a notable warming trend began, causing once again, record-warmth to engulf most of the Midwest and East for several days. Even this warmth did not last long, as a series of low pressure systems dragged a massive cold front into the East, not only producing heavy, flooding rainfall, but snowfall on the backside of the system. This cold blast was rather weak though, only producing a minimal lake effect response. In a few days time, a very strong cold front was dragged into the Midwest by a clipper system, which caused rapid temperature drops across a large region. Temperatures became unseasonably cold; the coldest weather of the season. High temperatures ranged from the -10's in the far Northern Midwest to the lower 10's in the lower Midwest and Ohio Valley. This generated a substantial lake effect response which lasted several days. Even so, dry air limited the amount of lake effect formation. By the end of January, temperatures began moderating before another major blast of cold air sent temperatures diving into the 10's, and high winds to a large portion of the Midwest and Great Lakes. It was during this time that several clipper systems delivered several periods of moderate snowfall to these regions.
By February, the month began rather cold for the East and Midwest. In coming days though, conditions began moderating over a large area, although this warm-up was mitigated by a deep snow pack just to the north. It was because of the pre-existing snow pack, as well as a few other conditions which lead to a monster Nor'easter to blast Southern New England with 3' to 4' of snow, winds to 90 mph, and whiteout conditions for a long period of time. This monster Nor'easter will not easily be forgotten on the minds of New Englanders, as it may turn out to be one of the top Nor'easters of all time. In fact, it landed in Boston's largest snowstorms of the city's records. The highest snow total was observed in Connecticut, with snowfall totals exceeding 40" of snow. By the middle of the month, temperatures have moderated again, and forecasters are once again very uncertain about the rest of the season. And this is the main subject of the latter half of this article.
It is looking more and more likely that the United States is impacted by a rather transient, progressive flow pattern, which will lead to near or just above normal temperatures through Friday, before a major trough dives into the Midwest and brings a shot of Arctic air (albeit not all that cold). It is possible that most of the area receives lake effect snow, as the largest lake effect event of the season possibly unfolds Friday and Saturday. By Sunday and Monday, a storm system will begin formation in the Southern Plains (possibly, but other model guidance such as the JMA and the NAVGEM-- the new version of the NOGAPS/GEM-- are suggesting a major coastal storm. While that isn't out of the question, I'm still rather skeptical of an earlier phase of the northern and southern stream waves), which could bring an icy mix of snow/freezing rain/sleet to the region. If the storm trends warmer, we could be looking at yet another rain event, but if it trends colder and further south, we may end up with a significant snowstorm. This remains to be seen, and it does bear watching for the time being. If it does occur, a large area from the Ozarks to the Ohio Valley/Great Lakes could receive over a foot of snow. At this time, the early week storm looks to be the warmer storm, and a possible, second storm could impact us by mid-week or later. As for the rest of the winter, its likely that it never does get truly cold and snowy, but rather bursts of intense winter weather, followed by tranquil periods of nearly spring-like weather, especially by the final days of February and early March. Early March looks to feature near normal temperatures, with possibly wetter than normal conditions, followed by an uptick in severe weather and warmer temperatures.
This is an image of tropical convective activity as viewed from infrared satellite imagery. As you can tell, the majority of the convective activity has shifted east of Indonesia and into Oceania. While this may seem very good for the MJO cycle to stall in Phases 1 and 2, another indicator from velocity potential and IR satellite suggests that the MJO is beginning to revamp back in the eastern Indian Ocean, causing the MJO cycle to propagate back into Phases 3-6, especially by the end of February. While these phases generally mean warmer than normal weather for the region, this time it may not due to the overwhelming presence of developing blocking, as well as a deep snow pack just to our north.
First, let's have a recap of the winter so far. On December 1, 2012, the vast majority of the United States began with increasingly above normal temperatures. In fact, many areas were breaching records that had not been breached in over 30 years. Widespread 60's and even 70's came as far north as Indianapolis in the Ohio Valley. Although warmth was experienced last year, this season's warmth has been mitigated by intense cyclones, and strong cold fronts from the northwest. A strong cyclone plowed through the Upper Midwest, bringing blizzard conditions to the Upper Midwest, while bringing chilly air into the East. While it was not substantial, as some have been in the past, it was quite a reversal from the record warmth of the beginning of December. As December progressed, it became cooler and cooler (as is expected), with more frequent storm systems, and RAIN (ugh). Yet, we had an exceedingly lack of accumulating snowfall. In fact, until about December 20th or the 21st, no more than 0.1 inches of snow was recorded at both South Bend AND Fort Wayne International Airports. Even so, an abrupt (more of a gradual pattern response though) pattern change commenced after a large cyclone traversed the Great Lakes in the days leading up to Christmas, bringing heavy rain to the Ohio Valley and East (once again). The cold front swept through, bringing high winds and much-needed colder air to the region. By that time, the threat of a major storm system was on the horizon, and it was predicted that the storm would mainly impact the Interior regions of the Northeast, largely sparing the coastal areas. Over the next few days leading up to Christmas, model forecasts began a quick reversed trend west with the cyclone, which shifted the snowstorm threat to the Ohio Valley through the Interior Northeast and New England. By Christmas Day, not only had a heavy snowstorm commenced over the Southern Plains, but a deep low pressure system was causing the development of widespread heavy, and sometimes severe thunderstorms across the Deep South. By Christmas Night, the low pressure system was moving northeast bringing widespread heavy snow from Arkansas to Indiana/Ohio, icing to Kentucky and parts of Tennessee, as well as heavy rain and thunderstorms to parts of the East. Heavy snow continued to spread northward and eastward, producing a large swath of 6-12" inches of snow. December ended with very cold weather across the nation, and record snow cover as well.
January began very cold across most of the United States, with temperatures well below normal over a large area. Snow cover was also well above normal as several weak, southern stream systems spread snow across the Midwest, Ohio Valley and Northeastern States. Lake effect snow continued as well from Lake Michigan, to Lake Ontario. By early to mid January, a notable warming trend began, causing once again, record-warmth to engulf most of the Midwest and East for several days. Even this warmth did not last long, as a series of low pressure systems dragged a massive cold front into the East, not only producing heavy, flooding rainfall, but snowfall on the backside of the system. This cold blast was rather weak though, only producing a minimal lake effect response. In a few days time, a very strong cold front was dragged into the Midwest by a clipper system, which caused rapid temperature drops across a large region. Temperatures became unseasonably cold; the coldest weather of the season. High temperatures ranged from the -10's in the far Northern Midwest to the lower 10's in the lower Midwest and Ohio Valley. This generated a substantial lake effect response which lasted several days. Even so, dry air limited the amount of lake effect formation. By the end of January, temperatures began moderating before another major blast of cold air sent temperatures diving into the 10's, and high winds to a large portion of the Midwest and Great Lakes. It was during this time that several clipper systems delivered several periods of moderate snowfall to these regions.
By February, the month began rather cold for the East and Midwest. In coming days though, conditions began moderating over a large area, although this warm-up was mitigated by a deep snow pack just to the north. It was because of the pre-existing snow pack, as well as a few other conditions which lead to a monster Nor'easter to blast Southern New England with 3' to 4' of snow, winds to 90 mph, and whiteout conditions for a long period of time. This monster Nor'easter will not easily be forgotten on the minds of New Englanders, as it may turn out to be one of the top Nor'easters of all time. In fact, it landed in Boston's largest snowstorms of the city's records. The highest snow total was observed in Connecticut, with snowfall totals exceeding 40" of snow. By the middle of the month, temperatures have moderated again, and forecasters are once again very uncertain about the rest of the season. And this is the main subject of the latter half of this article.
It is looking more and more likely that the United States is impacted by a rather transient, progressive flow pattern, which will lead to near or just above normal temperatures through Friday, before a major trough dives into the Midwest and brings a shot of Arctic air (albeit not all that cold). It is possible that most of the area receives lake effect snow, as the largest lake effect event of the season possibly unfolds Friday and Saturday. By Sunday and Monday, a storm system will begin formation in the Southern Plains (possibly, but other model guidance such as the JMA and the NAVGEM-- the new version of the NOGAPS/GEM-- are suggesting a major coastal storm. While that isn't out of the question, I'm still rather skeptical of an earlier phase of the northern and southern stream waves), which could bring an icy mix of snow/freezing rain/sleet to the region. If the storm trends warmer, we could be looking at yet another rain event, but if it trends colder and further south, we may end up with a significant snowstorm. This remains to be seen, and it does bear watching for the time being. If it does occur, a large area from the Ozarks to the Ohio Valley/Great Lakes could receive over a foot of snow. At this time, the early week storm looks to be the warmer storm, and a possible, second storm could impact us by mid-week or later. As for the rest of the winter, its likely that it never does get truly cold and snowy, but rather bursts of intense winter weather, followed by tranquil periods of nearly spring-like weather, especially by the final days of February and early March. Early March looks to feature near normal temperatures, with possibly wetter than normal conditions, followed by an uptick in severe weather and warmer temperatures.
This is an image of tropical convective activity as viewed from infrared satellite imagery. As you can tell, the majority of the convective activity has shifted east of Indonesia and into Oceania. While this may seem very good for the MJO cycle to stall in Phases 1 and 2, another indicator from velocity potential and IR satellite suggests that the MJO is beginning to revamp back in the eastern Indian Ocean, causing the MJO cycle to propagate back into Phases 3-6, especially by the end of February. While these phases generally mean warmer than normal weather for the region, this time it may not due to the overwhelming presence of developing blocking, as well as a deep snow pack just to our north.
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