Fire and Ice: Jet Stream Continues Stubborn Behavior
January 17, 2014
Stubborn Jet stream behavior has brought historic drought and january wild fire to california.
Scientists are finding evidence that “stuck” jet stream events may be related to human caused climate change.
Meanwhile, just as the east shakes off the “polar vortex” of misplaced arctic air that blanketed the area in early january, yet another cold air bubble is gathering.
The remainder or January is expected to be colder than normal, sometimes downright frigid. The pattern is very similar to the pattern during the first week of January when temperatures plunged more than 20 degrees below normal in the so-called polar vortex event. This time, the cold could stick around for a longer duration.
The European model’s (ensemble mean) pattern at high altitudes (500 mb, or around 18,000 feet) through the end of the month exhibits a huge ridge of high pressure over western North America and a big dip in the jet stream over the East Coast.
Referencing the maps below, remember that the high altitude winds parallel the thin black height lines generally running from west to east. Therefore, weather systems will be diving southeastward from Canada towards the East Coast during this January 21-31 period, with arctic air frequently following them.
The maps below show the average pattern for the 5-day periods ending January 26 (top) and January 30 (bottom). Long-range forecasters like using 5-day averages because the longer wavelength features, the ones easiest for the models to forecast, stand out. In this case, the averages are indicating that the pattern changes very little during the period and that the “nefarious” polar vortex is displaced well southward of its normal position.
Democracy Now video includes Jeff Masters.