I apologize for not posting anything since last Wednesday. I've been rather busy with this terrible cold of mine, and I haven't had much time to think, other than worry about school work.
Besides that, new data has come in that suggests that one of my options for the long range pattern was correct. In a past forecast, I stated that either the pattern change will occur during the week after Thanksgiving, or it will occur in mid-December, and now that seems to be the more likely case. As I stated in the December outlook, the first half of December looks near normal (cold shots "equalizing" the the warm periods), with only transient, short lived periods of colder, snowy weather. Well, it appears this forecast will hold as model guidance is now suggesting that the Gulf of Alaska Vortex will FINALLY shift west. Originally, when models were forecasting the "pattern change" for early December, they were suggesting that the Gulf of Alaska vortex would stay put (as well as keeping the Bering Sea omega block). I should have recognized that a "pattern change" cannot occur unless the Gulf of Alaska vortex breaks down or shifts west. At this time, it is expected that the Gulf of Alaska vortex will shift to near the Aleutian Islands around the December 10th timeframe. When that occurs, it is likely that a wave of Arctic air will rush southward into the United States, bringing the season's first period of "real" winter weather, and the possibility of our first accumulating snow.
At this time, it is not set in stone, and this date may end up being pushed back into Christmas week. Right now, the analogue years are really lining up for a "modest" first 2/3 of December, becoming quite harsh the last week, so this may be what will happen.
Have a great week!
Besides that, new data has come in that suggests that one of my options for the long range pattern was correct. In a past forecast, I stated that either the pattern change will occur during the week after Thanksgiving, or it will occur in mid-December, and now that seems to be the more likely case. As I stated in the December outlook, the first half of December looks near normal (cold shots "equalizing" the the warm periods), with only transient, short lived periods of colder, snowy weather. Well, it appears this forecast will hold as model guidance is now suggesting that the Gulf of Alaska Vortex will FINALLY shift west. Originally, when models were forecasting the "pattern change" for early December, they were suggesting that the Gulf of Alaska vortex would stay put (as well as keeping the Bering Sea omega block). I should have recognized that a "pattern change" cannot occur unless the Gulf of Alaska vortex breaks down or shifts west. At this time, it is expected that the Gulf of Alaska vortex will shift to near the Aleutian Islands around the December 10th timeframe. When that occurs, it is likely that a wave of Arctic air will rush southward into the United States, bringing the season's first period of "real" winter weather, and the possibility of our first accumulating snow.
At this time, it is not set in stone, and this date may end up being pushed back into Christmas week. Right now, the analogue years are really lining up for a "modest" first 2/3 of December, becoming quite harsh the last week, so this may be what will happen.
Have a great week!
 |
| Jet stream pattern as forecasted by the European model. It shows a large dip in the jet stream around 10 days from now, which could mean a *massive* Arctic wave into the United States. |
No comments:
Post a Comment