Tag: "winter storm"
**Brian Peters will be along with the regular morning discussion and Weather Xtreme video shortly**
ENJOY TODAY: We expect a sunny sky today with a high around 60 degrees… but much colder air blows in here tomorrow, and things go downhill quickly after midnight Sunday night.
WINTER STORM WATCH: NWS offices in Huntsville and Birmingham have issued a winter storm watch for late Sunday night (after midnight) and Monday… this discussion will mainly involve “round one” of this winter storm which comes Monday.
TIMING: Wintry precipitation will begin over far Northwest Alabama around midnight tomorrow night; it will expand and cover much of North and Central Alabama by 3-5 a.m. Temperatures should creep above freezing at some point Monday afternoon with slow improvement, but expect very hazardous travel conditions between midnight tomorrow night and 3:00 p.m. Monday. However, icy travel could linger into Monday night for far North Alabama, mainly north of the Tennessee River.
ACCUMULATION POTENTIAL: We project 2-4 inches of snow for that part of Alabama north of a line from Vernon to Jasper to Oneonta to Gadsden. To the south, it will be mostly freezing rain and sleet, where ice accumulations to 0.3″ are possible. Remember, this is just a guideline; the precipitation type won’t change exactly along these lines.
Some icy spots are possible as far south as U.S. 80 (Demopolis to Selma to Montgomery to Opelika), but it will be mostly rain for those communities, and points south.
IMPACT: Travel will be severely impacted, with bridges becoming ice covered quickly. With temperatures in the 20s early Monday morning, even black top roads can become ice covered and very dangerous. While major, widespread power outages are not expected for now, where ice does accumulate to 0.3″, some power outages are possible. Preparing for power outages is never a bad idea, in case a worst case scenario develops.
ALABAMA POWER IS READY, ARE YOU? Our friends at Alabama Power are monitoring the forecast closely, ready to deploy people and assets to quickly address any outages that might occur. Read a special message from Ike Piggot about their commitment to their customers.
WIND CHILL ADVISORY: We should also mention the NWS Huntsville has issued a wind chill advisory for tomorrow; wind chill values could drop below zero at times as the cold air rushes in.
CONFIDENCE: Our forecast confidence is relatively high for the events expected Monday.
IMPORTANT: Please read this post about winter weather forecasting. As you know, we have a limited skill set in dealing with winter storms in Alabama, and forecast changes are very possible as we get closer to the event. Be sure and check the blog often this weekend.
ROUND TWO: For now we expect just a cold rain Monday night, but there is a decent chance the rain changes to snow on Tuesday before it all ends.
This looks like a rather quick hitting event, but it could produce snow amounts of 1-2 inches during the day Tuesday, with accumulation possible as far south as a line from Eutaw to Centreville to Calera to Sylacauga to Roanoke. Confidence is lower in this forecast, and the exact impact remains uncertain. However, there is real chance it could impact travel Tuesday afternoon, Tuesday night, and possibly Wednesday morning across North and Central Alabama. We will be much more specific about this threat tomorrow.
Wednesday looks cold and dry.
Stay tuned for frequent updates throughout the weekend.
Looks I have over 4,000 pictures within the past 24 hours… here are some special ones I have selected tonight here in the old, lonely weather office…
Snow is getting heavier… this shot below is from the Wellborn area (just west of Anniston)
This image below is from the Bagley community of north Jefferson County
And this image below is from Ross Bridge in Hoover…
Multiple wrecks across the western third of the state, including Tuscaloosa. This shot is from Skip Baumhower, just south of Tuscaloosa on I-59/20. This wreck just happened…
Below is a shot captured of the Hugh Thomas Bridge between Tuscaloosa and Northport with our SKYCAM.
Road conditions will deteriorate across the rest of the state in coming hours. Many reports of snow in Shelby County now, south of Birmingham.
See our live radar composite of the winter storm:
Most of what you see over Alabama is NOT reaching the ground; it is evaporating into the cold, dry air near the surface.
A few mid-morning notes…
*Generally speaking, the storm is developing as expected. There has been severe weather along the Texas Coast this morning, and dynamic forcing is excellent.
*SPC believes we will have thunder with the snow and ice tonight, especially south of I-20. But, I would image there could be some reports of thundersnow north of I-20 late tonight as well, but it will be isolated.
*The new 12Z NAM is printing 0.58″ liquid with this event for Birmingham. Equates to heavy snow for North Alabama, and potentially a crippling ice event for some parts of Central Alabama tonight.
*This is NOT in the same league as the 1993 blizzard. But, I do believe we will see isolated 8 inch snow amounts over North Alabama, and the ice over Central Alabama was not a part of the 1993 storm; that one was all snow.
*NWS Jackson reports a pretty good coating of sleet and glaze on elevated objects at the Jackson, MS airport.
Our projected forecast below is not, more than likely, going to change before the event begins. Remember, travel will become difficult, if not impossible, tonight across much of Alabama north of U.S. 84. The most significant precipitation will come after 6:00, with snow and freezing rain heavy at times after midnight. Stay tuned for updates throughout the day….
Here is an early morning look at the winter storm headed for Alabama; Brian will be along shortly with a fresh Weather Xtreme video….
See the forecast accumulation graphics from me, and the Birmingham NWS below…
Not much difference in the snow projection… the NWS is using 3-6″ for Birmingham, Tuscaloosa, Anniston, and points north, while I am using 3-7″. The NWS Huntsville is using 4-7″ for their counties in North Alabama. I still strongly believe there will be some 8″ amounts in spots across high terrain of East and Northeast Alabama.
There will be a sharp cut-off of snow amounts south of I-20, where freezing rain will be more of a problem. Ice accumulation of 1/4 to 1/2 inch is very possible across this part of Central Alabama, and is very problematic. One-half inch of ice might sound like much, but it is enough to bring down trees and power lines, and make for widespread power outages that can last for more than 24 hours in places.
NOTE: There is little skill in determining the exact line between significant snow, and significant ice. This is the greatest challenge in this forecast. For now, the line most likely will be running a little south of Tuscaloosa, Birmingham, and Anniston, but nobody knows the exact placement at this point. Below that line is where a major ice event is likely and power outages will be an issue. Keep a close eye on updates today for adjustments to that potential snow/ice line.
The NWS has issued a winter storm warning for mostly snow for these counties: Blount, Calhoun, Cherokee, Clay, Cleburne, Etowah, Fayette, Jefferson, Lamar, Marion, Pickens, Randolph, Shelby, St. Clair, Talladega, Tuscaloosa, Walker, Winston, Franklin, Lincoln, Moore [TN] and Colbert, Cullman, De Kalb, Franklin, Jackson, Lauderdale, Lawrence, Limestone, Madison, Marshall, and Morgan.
The NWS has issued an ice storm warning for mostly freezing rain for these counties: Autauga, Barbour, Bibb, Bullock, Chambers, Chilton, Coosa, Dallas, Elmore, Greene, Hale, Lee, Lowndes, Macon, Marengo, Montgomery, Perry, Pike, Russell, Sumter, Tallapoosa.
WHEN? Precipitation is now falling over South Mississippi and extreme Southwest Alabama. More than likely, some of this is not reaching the ground, but the lower levels will saturate soon and all of this will be moving northeast. While we could see some freezing rain or snow this afternoon, the bulk of the precipitation will come from 6:00 tonight through 8:00 a.m. tomorrow. Snow and freezing rain could be heavy at times after midnight.
TRAVEL: Travel will become difficult, if not impossible, tonight and tomorrow morning due to snow and ice. Expect airport delays, and it is possible some airports will have to close for a while. In addition to Birmingham-Shuttlesworth International Airport, this storm will also impact airports at Atlanta, Nashville, and Memphis.
POWER: In the ice storm warning zone, there could be power outages due to the weight of the ice on trees and power lines. A few scattered power outages are possible over North Alabama as well due to the snow, but it should not be a widespread problem there. Review the ice storm warning counties above to see the places in greatest danger of power outages.
DON’T FORGET: With every winter weather event in Alabama…
*Some will be delighted with the amount of snow they get, others will be severely disappointed
*There will be surprises as the event unfolds.
Again… Brian will be along shortly with the morning weather xtreme video, and we will have running updates throughout the day.
Scroll down for a treasure trove of information on what is coming our way. All the videos, maps, etc should answer many questions, but let’s break down some of the most important questions…
*WHEN? A wintry mix of sleet and freezing rain could begin over Southwest Alabama as early as 6:00 to 9:00 a.m. tomorrow. By this we are talking Washington, Clarke, Monroe, Choctaw, Marengo, and Wilcox for that early start. For the Tuscaloosa/Birmingham metro areas, a wintry mix will begin by mid-afternoon (2:00-5:00), but initially surface temperatures will be above freezing and we won’t expect any travel problems before dark. For East Alabama, it all begins in the 4:00-7:00 p.m. time frame. For North-Central Alabama (the ABC 33/40 viewing area), getting to church, and home from church should not be a problem.
The worst of the storm will come from 8:00 tomorrow night through 8:00 Monday morning. The precipitation will be over by late morning Monday.
TRAVEL BY ROAD? Roads will become slick and dangerous over Alabama Sunday night. The NWS in Mobile is concerned about a major ice storm for some of their counties in South Alabama, generally north of of a line from Grove Hill to Monroeville to Greenville to Luverne, and even down there bridges could become a sheet of ice. Up this way, heavy snow and some ice will make for difficult, if not impossible travel by late Sunday night and through Monday morning. If we see as much snow as we are predicting across North Alabama, all of this snow won’t melt Monday afternoon, and we could see lingering problems into Tuesday morning.
TRAVEL BY AIR? There will be major issues with snow, and perhaps some ice, at Birmingham-Shuttlesworth International Airport and Hartsfield International Airport in Atlanta. It will be very difficult to fly out of these airports Monday morning, and expect major delays all the way through Monday night. I would not be surprised if these airports had to close for a brief period. Also, keep in mind snow will be an issue for the airports at Nashville and Memphis.
IS THIS LIKE THE BLIZZARD OF 1993? No. This storm is not in the same league, although it will be very memorable. It is rare to have a snow this significant across Alabama.
CAN WE EXPECT POWER OUTAGES? We all have great concern that there will be strip of freezing rain somewhere through Central or South Alabama that will bring enough ice load for trees and power lines to come down. I would say the greatest risk of this will be south of a line from Eutaw to Clanton to Alex City to Lafayette, and north of a line from Grove Hill to Monroeville to Greenville to Luverne to Eufaula. There won’t be serious icing across all of that region, but a strip of heavy freezing rain and a major ice load is a very real possibility.
To the north, heavy snow could result in some power outages over North Alabama as well, but they should not be as widespread as the ice zone to the south.
WHAT ARE THE CHANCES OF THIS FORECAST BEING WRONG? There is ALWAYS a chance the forecast is wrong! But, confidence is very high in the overall event… the issue is small scale details now we can’t determine until the storm system is formed and we can see it clearly on radar and satellite. There will be clearly heavy snow over North Alabama, and a chance of significant ice somewhere over Central or South Alabama.
DURING THE STORM, CAN I HEAR YOU VIA RADIO: Yes. In Birmingham, we are on the Cox station family. WZZK (104.7), WODL (97.3), WBHK (98.7), among others. In Tuscaloosa, it is the Citadel family of stations… including B101.7 and 95.3 “The Bear”. And, over in East Alabama, we will be on WTDR, Thunder 92.7 in Anniston/Oxford.
And, you know my two points…. in every Alabama winter storm…
*There will always be those who are delighted with the amount of snow they see, and others will be severely disappointed.
*There will be surprises.
As I posted here a day or so ago, with any winter weather event, everybody has an opinion, like everyone has a belly button. Jim Stefkovich of the NWS sent me his projected snow accumulation… which is very similar to mine (NWS has 3-6″ for Birmingham, while I am at 4-8). I think most are on the same page here, and now we just await the the system to get it’s act together and get on the board…
Below is the NWS projection and the one I amended earlier this morning.
Writing this late Saturday morning, about 30 hours prior to the expected beginning of a significant winter storm for Alabama.
You can scroll down for a look at our forecast and projections… but we are just about at that time when we quit flying with instruments (computer model output), and begin to fly visual (look at actual observed data). Sure, there will be many more runs between now and tomorrow (the RPM runs every three hours), but don’t expect much change in the forecast this afternoon or tonight. You can read J.B.’s post below this one about the surface low now being on the board. Here are some points about what we know, and what we don’t know…
*Confidence is very high that there will be a significant amount of snow across parts of North or Central Alabama.
*Confidence is high in that some freezing rain will be involved in a zone across Central, or maybe even South Alabama.
*Confidence is high that the most intense part of this storm will be from about 8:00 p.m. tomorrow through 8:00 a.m. Monday.
Now, this is what we struggle with…
*Placement of the heaviest snow band. With systems like this, a deformation axis will usually become established. This is an area in the atmosphere where winds converge along one axis and diverge along another. Lifting is enhanced, and you get heavy snow. This band is usually 30-50 miles wide, and that is where we fully expect some 8 inch totals. This band could be anywhere from Birmingham and I-20 to Huntsville, along U.S. 72. Away from that heavy snow axis, snow amounts of 4 inches are likely 30 miles on their side, and away from there the amounts will greatly drop off.
*Placement of the axis of heavy freezing rain. This is the biggest issue, since a long period of freezing rain will bring an “ice storm”. Freezing rain is simply rain that falls in liquid form, and then freezes on impact with surface temperatures at or below 32 degrees. If there is enough ice, then trees and power lines can come down, and we get into a big mess. Seems like the best bet for this will be roughly along U.S. 80, but it could be a little farther to the north, impacting places like Greensboro, Clanton, and Ashland.
And, these two points are true with every Alabama winter storm…
*Some will be delighted with the amount of snow they see, and others severely disappointed.
*There will be surprises.
We all know that snow and ice don’t follow those nice, straight lines we draw on the maps (like our forecast below). These maps give a simple visual guideline of what we expect based on what we know now. The next changes in this map will be based on actual observed upper air and surface data, with a much smaller consideration from model guidance.
Here is a look at the 12Z snow accumulation output from the RPM model…
We have to respect this model’s performance with the winter weather events this season (it has done very well), and it shows the snow maximum of 4-8 inches north of I-20, with lighter amounts to the south. We note the 09Z RPM showed 10 inches of snow for parts of East Alabama counties like St. Clair and Calhoun.
And, below is the 06Z NAM snow accumulation output:
The NAM shows 4-6 inches for the Birmingham metro.
Based on this model output, we will adjust the accumulation forecast just slightly… the main changes….
*Reflecting the chance for 4-8 inches farther into North Alabama.
*The heavier totals (6-8″), more than likely will come over higher terrain of East Alabama. Four inch amounts will be more common.
*There will be sharp cutoff of the heavier snow accumulation south of I-20, but some light accumulation is possible down into South Alabama.
*Forecast soundings are troubling for the U.S. 80 corridor… hinting at potential for 1/2 inch ice accumulation for some spots down that way, which could mean enough ice for scattered power outages. We will really have to watch this… and again there is little skill in identifying the exact placement of the heavier freezing rain before the event begins.
*The main impact of this storm will come from about 6:00 p.m. tomorrow through 8:00 a.m. Monday. Travel across North nad Central Alabama will become difficult, if not impossible at some point Sunday night.
As always, stay tuned for changes as the storm begins to develop and finally gets on the board so we can take a look.