New Year Begins Mild...Return to Cold Likely
In the past 24 hours a strong storm system has sparked an outbreak of powerful thunderstorms along the Mississippi Valley. The Severe Storms prediction center reporting 40 confirmed tornadoes have torn over parts of Illinois, Missouri, Arkansas and Mississippi.
According to The Associated Press, at least six people have been killed and several more injured by the twisters on New Year's Eve. Dozens of homes have been damaged or destroyed and thousands have been left without power. Golf ball- to baseball-sized hail pounded many cities and towns across the region.
This outbreak is a result of warm moist air coming out of the Gulf of Mexico colliding with Dry Arctic air swinging down from the Northern plains. Strong winds aloft have provided perfect tilt to these thunderstorms to keep persistent updrafts going with a mass exodus of air from the surface thanks to upper level diverging winds.
High pressure off the Mid-Atlantic coast is giving us great weather to start off the year 2011. A mild start with Plenty of sunshine this morning with light SW winds at the surface will allow temps to climb into the Lwr 50's...and may even climb into the mid 50's in a few areas if the sun holds strong through the afternoon.
I am expecting high clouds to be increasing this afternoon ahead of the rain to our west, which will be moving through tonight in a weakened state. Showers are likely after midnight through the morning hours tomorrow. These will be scattered showers where not much more than a tenth-.20" of rain will fall at the most. Showers will linger until 10 AM Sunday ...before clouds start to break by the midday with increasing sunshine from west to east during the afternoon. It will take until 2-4 PM for the sunshine to reach the coast. Temps will start mild, near 50, and start to fall off into the Lwr 40's by sunset.
Cooler air will be on the move Sunday night with clearing skies. Brisk NW winds will develop Monday. Seasonally cool for much of the week ahead with mainly dry conditions. We will track a short wave rolling through Tuesday night...but moisture will be limited so I am not expecting much more than clouds. Cold air advection will follow in behind this disturbance to keep the cool down going through the end of the week with highs bottoming out near 30-33 degrees.
Another more vigorous shortwave could be digging in towards the Great Lakes and through New England for the end of the week. There is the potential Clipper Low to slide south of New England and deepen just off the coast for a brief burst of accumulating snowfall late Friday into Early Saturday. That is simply one measly Euro run on a Saturday morning for an event a week a away...so that will obviously change in many forms before we get a handle on that.
The pattern a whole has taken a break. The blocking pattern has broken down a bit. The real Arctic air is exhausted in Canada...and has shifted to the other side of the Globe....but it is cold enough that when steered into the US it can cause storms...as we are seeing now. This coming week will be a tolerable chill..with a breakdown of a brief thaw.
Looking ahead, behind any disturbance which happens at the end of the week...cold arctic air will begin to press south again with persistent NW winds out of Canada. The week of the 10th-15th will be much colder than what we will see this week. Any big storms? I don't see any now, but they do have a history of creeping up on us from time to time!