LET THE WINTER GAMES BEGIN...
There's so much weather on the table it's hard to even know where to begin. Before I get to the snow that's coming this week, I do think the thunderstorms we had Sunday night are worth a mention considering the time of year. I can't remember an occasion when I saw that much lightning (sharp lightning at that) December 27th. Aside from the thunder and lightning, the wind was howling, the temperature was 37 and pea size hail was falling. This is the year that defies all logic!
I should also add this, the December 15th severe weather outbreak in Iowa is now the largest in state history, based on preliminary data from the National Weather Service. The NWS identified a total of 43 tornadoes from that event which places it atop the list of all-time tornado outbreaks in the modern era, which extends as far back as 1950. Are you kidding me!
Of the 43 tornadoes identified, 19 were rated EF-1, and 17 were EF-2 tornadoes. The 17 tornadoes rated EF-2 also makes it a record for the number of tornadoes of that strength, or greater, in a single day in Iowa. The previous record was 16 on June 7, 1984. Iowa only averages about 6.25 tornadoes each year that reach EF-2 strength or greater. Iowa averages around 48 tornadoes per year and we had 43 on a single day (IN DECEMBER!). Up until this year, only 4 tornadoes were recorded during the month of December, making this particular storm not only an outlier for any time of year, but an EXTREME anomaly for December. June and May, in that order, account for most of the tornadoes in the state in any given year.
LET THE WINTER GAMES BEGIN
Just to make things interesting, now the pendulum swings towards winter. The pattern is finally growing cold enough that snow will become in factor in several more systems that will impact the area in the coming week. As it stands now, three different disturbances have the potential to bring snow, with the last of the three potentially the strongest producing the most significant impacts.
The first system is already on our doorstep and the worst of the wintry impacts with it will be located to the area near and north of I-80. It's due to a wave of low pressure which tracks across central Missouri. Snow, or a rain snow mix develops early Tuesday and then quickly spreads northeast by mid-morning. A band of freezing rain is also possible on the southern flank of the wintry precipitation shield. As warmer air advects northeast during the day, any mix in the south will change to rain by noon, especially south of I-80. The area between I-80 and HWY 30 is challenging as some models keep snow or mixed freezing rain, sleet, and snow going the entire event. Further north near HWY 30 (and especially closer to HWY 20), snow appears to be the dominant precipitation form for the duration of the storm. Here 2-4 inch snow totals are expected with some local amounts up to 5. Further south in the corridor between I-80 to HWY 30, 1-3" amounts with some icy accumulations are possible. South of I-80 snow and ice accumulations of an inch or less are likely before the transition to rain takes place. Little if any problems are anticipated south of HWY 34.
The NWS in the Quad Cities has issued a winter weather advisory for the northern 2/3rds of my area from 6am to 6pm Tuesday. These areas are likely to experience travel issues with problems more pronounced the further north you go.