December 26, 2012
Post Storm Analysis From The Christmas Storm System That Hit The Gulf Coast Region.
First, thing this past severe weather outbreak is going to go down as a significant event and one of the most significant for Christmas Day in history it matches back to an event in 1969 other than that no other event has ever occurred on Christmas this big. The image above shows just some reports of what happened during the event as there was a total of 34 estimated tornadoes per the Storm Prediction Page. There was also well over 70 wind reports along with a few large hail reports. The blue boxes above also represent another special feature to this storm and that is the Snowstorm that occurred on the North side of the low. The tornado that hit in Mobile Alabama was probably initially the largest of all the tornadoes on the day as many photos and images are available of this storm from people that where near this storm. However I am going to show you a different perspective to the storm, I was storm chasing and I happened to come up on the West side of this storm and this is what it looked like from about 25miles west.
As we can see in the image above we have a developed thunderstorm but the unique feature is that it was embedded inside a more significant outflow boundary from the storms that were associated with the frontal boundary. The Mobile tornado came from a low elevated thunderstorm cloud as you see in the image above. This image was taken during the late afternoon from Eastern Jackson County in Mississippi looking towards the east.
The lightning bolt on the image above was also another storm image that I got of a gust front moving into the region. I was able to measure a wind gust with this gust front of 52mph through my hand held weather station. Here is an image of that gust front.
This gust front was responsible for minor damage as tree branches breaking off the trees. The most significant event of the day was the Mobile AL tornado. This tornado also proved a fact in that “Tornadoes can strike the same spot twice”. This tornado hit the exact same area of Mobile that was hit earlier the week before with a smaller EF-1 Tornado, based on the images available and the videos of the Mobile area I would be willing to say that this tornado was larger in size.
This severe weather event started in the early morning hours of Christmas day back in the Gulf Coast region of Texas as it spawned tornadoes in this region before it advanced into Western Louisiana. Once, the low got into Western Louisiana a significant squall line setup along the front, however about 100-125miles ahead of that a severe line of storms began to develop also known as super cell storms, these were responsible for the majority of the tornadoes that hit the region. This line based on radar images also eventually gave way to a third squall line that setup even further east over the Mobile Alabama area was a third line of these storms.
By 5:00pm CDT on Christmas Eve we were dealing with three significant lines of storms, the furthest east line was moving through Mobile Alabama, while the second line was moving through the Mississippi Gulf Coast and northward into Central Mississippi, then the frontal boundary line of storms was just leaving Eastern Louisiana. During this time, we also saw the heavy snowfall on the Northwest side of the storm which started early in the day over Oklahoma with many places getting accumulated snowfall along with Blizzard warnings being issued for the region. During this time as the low pushed further North-Northeastward we saw wrap around moisture reach down into Northeast Texas and Northern Louisiana where they even recorded snow during this event. By the later afternoon hours the snow advanced into Arkansas and this region took the brunt of the snowfall with some places getting over 12inches of snow along with strong winds which lead to more blizzard conditions for the region.
By around 8:00pm CDT the center of the low had advanced into Northeast Mississippi and behind it we saw the snow continue in Arkansas, however spread eastward into the Memphis area where they even got near 2inches of snowfall and then it spread into Northern Mississippi and Alabama where places here got just mostly flurries except along the Mississippi river in Mississippi places saw close to 1inch of snow. At the same time as the snow was going on over the Northern part of this storm, we were still dealing with severe weather as it began to push the front line of storms into Eastern Alabama and the Florida panhandle, while the frontal boundary began to push through Eastern Mississippi with one more big push of wind and rain as totals around Ocean Springs Mississippi hit about 0.50in of rainfall along with another wind gust near 45mph.
The significance of this event is how far south the snow fell giving white Christmas’s to places that usually don’t have white Christmas’s and also the magnitude of the severe weather. As mentioned earlier in the article this is going to rank as one of the strongest Christmas Severe weather outbreaks in history.
This storm was a typical Pacific low pressure system that moved rapidly out of the Pacific Northwest and into the Rockies and then with the strong Jetstream sitting over the region it created a very unstable environment allowing this storm to get strong rapidly over the Gulf Coast region which led to this setup for the Christmas 2012 Winter and Severe Weather Outbreak.
Featured Image Credit: Joshua Kelly