A note from the Doc: The references to planets and constellations on this site are not astrological in nature, merely the clearest way to reference these positions and angles. For more, please read: Astrology or Astronomy »
The early occurrence of persistent, warm maritime flow from the Pacific Northwest horizontally across the Great Plains of Canada and the northern tier of states in the United States, has broken records for the warmest January ever. This record breaking warmth was accompanied by record breaking rainfalls in Vancouver BC that had rain for 29 out of 31 days in January 2006. The horizontal flow known as zonal flow has had the jet stream moving across the zone of latitude that is the border between the US and Canada. Aside from the obvious reference to generally warming temperatures and the global warming debate, the pattern originated in an unusually strong zonal flow of the jet stream at the 500mb level, in the latitude of Vancouver Island and the longitude between the western coast of Alaska and the middle of the Gulf of Alaska. This was also the pattern behind a mid-December warming trend cited in Doc Weather in the article on Mercury andVenus
The chart for figure 1 shows the warming pool (orange zone) coincident with the direct motion of Mercury across the Gulf of Alaska superimposed with the zone of strong upper level winds (red zone) that began to drive the jet into its unusual horizontal flow. Once the jet locked onto the pattern there was very little to change the flow through the month of January since the jet curves that supported the zonal flow kept an almost continuous signature of high pressure (blue H's) for most of the month of January. The combined extend of this high pressure signature is depicted in figure 2.
In this chart it can be seen that the highs teleconnected with each other across the Gulf of Alaska and the southern portions of the continent keeping the jet stream pushed to the north out of its normally much more southerly position for the winter. This northern displacement of the jet stream kept the ice melting in Winnipeg and the rains pouring into Vancouver, BC, while the rest of the continent saw clear and temperate weather for the first month of the new year.
Enter February and the great Blizzard of "06 to break up the intoxicating spell of the warmth so that the eastern third of the country remembers that this is winter after all. This storm was a classic example of a nor'easter The feature that kicked off the storm was the development of a strong high pressure area over the West Coast. This pattern began on February 7th as a ridge built up out of the south over California. For the winter of 2006 the jet curves have been centered over the West Coast, with the tip of the disturbance diamond over the Great Basin. Earlier this placement was the site of the persistent high pressure that pushed the jet to the north.
However, the storm season was not to be denied. Figure 3 shows that in February 7th high pressure values arose on the two outer jet curves of the diamond (blue curves) and low pressure arose on the two inner (red) jet curves. Figure 3 shows the ridge pattern with the accompanying labels that composed the disturbance diamond for this period. The ridge formed out of the crossing point of the two outer jet curves (blue) that were aspected to high pressure from the western points. A strong high surged north along the west coast from the crossing point of these two jet curves. To the north, at the crossing point of the two inner 72° jet curves (red), a low formed on the 10th. This low was the seed of the blizzard of 2006. It formed in the bowl of the crossing point of the two low pressure jet curves that were situated between the two high pressure jet curves. In this type of pattern the high and the low work around each other in a kind of dance. In this instance the high surged up the coast to the west and the low dropped down the eastern side of the ridge. This is a standard pattern for these relationships.
In figure 4 the result of a shift of Saturn on the 10th is illustrated. Saturn put high pressure on both of the western points. This gave great impetus to the forming of a blocking ridge along the West Coast. A typical motion for this is that the surging ridge moves to the north along the mountains and pushes the jet up into BC. This is what happened when three of the four jet curves in the disturbance diamond over the Great Basin (yellow) were suddenly aspected to high pressure (blue). The descending low on the eastern side of the ridge, followed the only jet curve that was aspected to low pressure down into the central Plains states. From there the low curved into the Corn Belt and then encountered a high pressure air mass that formed between the 45°jet curve over Florida and the 22° jet curve over the Atlantic. This air mass formed from the 45° and 22° jet curves from the lunar point in the east. This high (blue) kept the low from exiting the continent at low latitude. Instead, the low curved up the East Coast drawing in warm moisture from the Gulf Stream off of the East Coast and clobbered the whole East Coast from the Carolinas to Maine. The transiting low intensified when it ran into the 45° jet curve from the lunar point (red) that was aspected to low pressure across the Maritimes.
Based on these patterns the February outlook for Doc Weather predicted storms for this quadrant of the continent during this time period.