The early chill of November may have many of you wondering what is in store for the upcoming winter. Well, I have been wondering about that over the past few weeks as well working on my winter forecast. This is something that I enjoy doing. As a Tennessee valley native, I am always wondering if we will see snow and just how cold it might be. Long range forecasts are always going to have its flaws, but as I learned in climatology courses we look to the past to look to the future.

So, I have compared data from 2008 so far to other years with similar patterns. I can then look at similar winter patterns or “analogs”. These analog years can give you an idea of how other past winters have played out. Keep in mind that no 2 winters are the same. And, even if all of the past winters have a similar pattern, if doesn’t mean that the next winter will follow the same pattern. So, you can see the challenge and understand that the skill level involved is still in its infancy. But, I like a challenge, so here is my take on what we might expect for the winter.

Watch the Video, or read the Text version below:

Let’s start with 2 other outlooks that have already been released. The NOAA December through February outlook for the Tennessee Valley continues the trend of slightly above normal temperatures and possibly near normal precipitation. Here is a link to that NOAA Outlook. The 2009 Old Farmers Almanac is projecting a wetter and cooler than normal winter for the Tennessee Valley. Click here for the Almamac’s web site. So, we have 2 totally different views of the season ahead. The Almanac uses a secret formula, but is loosely linked to the solar cycle and sunspot activity which does have a degree of accuracy for seasonal trends. The NOAA outlook is based on the influence of the La Nina or El Nino patterns. NOAA is projecting a neutral pattern where neither the La Nina or El Nino has a major influence. Typically, a neutral pattern tends to lead to slightly milder than normal conditions. The solar cycle/sunspot activity has been something that has to be looked at carefully. We are experiencing a prolonged period of minimal sunspot activity, which in the past has led to colder than average conditions.

My forecast based on looking at past seasons can be summed up in one word….Average. I am projecting a winter that might exhibit average temperatures and average precipitation. Keep in mind, that an average winter will be cooler than the past few winters that have been above normal. I see the chance for some prolonged periods of very cold conditions only to be countered by upswings in temperature to follow.

Past winter patterns or analogs to this past year suggest that rainfall might be near normal to above normal. However, none of these analogs were during a drought, so I am little cautious with my forecast and am keeping the rainfall outlook to near normal (hoping it goes above). Past patterns also suggest that the local snowfall potential should be about normal and I will go with that as well. Locally, we average 4.8 inches of snow per year. That amount has come down during the past 10 years from 5.0 inches. So, I do believe that there will be some snow potential. And, as it often goes, there are usually 2 snow events in the mountains for every 1 event in the valley. That ratio should continue this year. Past similar patterns have yielded 2-3 small events in the valley, and that looks sufficient in my forecast for this winter.

As with any season, the threat of an ice storm always lingers. Snow can be fun, but ice is not. 2 of our most devastating ice storms occurred during the winters of 1960 and 1973. With the chance that rainfall might be a little higher this winter, I am concerned about our chances for having an ice event.

So, there you have it! Only time will tell what will transpire this winter. You can always depend on the Storm Track 9 Team to keep you updated on any winter weather situations which might develop.

David Glenn
Storm Track 9 Chief Meteorologist

The average low temperature was Wednesday is 39, but we should be way below that value! I am expecting overnight temperatures to drop into the middle 20s area wide through Wednesday morning. This would mean that a “hard freeze” will be possible. A hard freeze has varying definitions in differnt parts of the country. Locally, a hard freeze is when we can expect temperatures to drop at or below 26 degrees for a duration of 4 hours or longer. That could indeed be the case for many spots by Wednesday morning. Here are a few expected low temperatures:

Chattanooga: 25
Cleveland: 25
Dalton: 25
Lafayette, GA: 24
Dayton: 24
Athens: 24
Blue Ridge: 23
Monteagle: 22
Lookout Mountain: 22
Signal Mountain: 22
(upper 10s at higher elevations 3000 ft and above east of the city)

So, what do you need to do during a hard freeze? Be sure to heat your home safely. make sure any space heaters have no obstructions or nearby flammable materials. Protect any tender plants. Provide your pets with a warm place to sleep and water in a location that won’t freeze. Check on your elderly friends and family to be sure that they are staying warm.

After Wednesday morning, morning temperatures should not be quite as cold Thursday and Friday (but still below freezing). We could experience temperatures in the 20s again Saturday morning. Below normal temperatures should continue through the upcoming weekend, but still dry. More details in our 7 Day Forecast. Check out my video forecast for a 14 day temperature outlook.

David Glenn
Storm Track 9 Chief Meteorologist

Many thanks to the 2nd grade class at Rivermont Elementary! I had the chance to visit the school Friday and read to the class. I appreciate Pam Howard, school counselor, for inviting me to take part in the reading event at the school.

David Glenn
Storm Track 9 Chief Meteorologist

Track the rain on the Storm Track 9 Live Radar

Track the colder temperatures on the Storm Track 9 Live Neighborhood Net

An abrupt change in our local weather is on tap for the weekend. A surge of Gulf moisture from the south will move into the Tennessee Valley in advance of a strong cold front through Saturday morning. This will provide most of our local region with some soaking rainfall through the night. A few thunderstorms could occur during the night, but most should stay below severe levels. On average, an inch of rain is possible through Saturday morning.

The cold front should pass through Chattanooga Saturday morning which will end the heavy rainfall. Scattered light rain will still be possible even with the passage of the front. Breezy and colder conditions can be expected behind the front as a brisk northwest wind kicks in. Temperatures Saturday morning should be in the lower 50s and then drop to the 40s by late Saturday afternoon. By late Saturday night, local temperatures will drop to the middle/upper 30s. Dry conditions, but below normal temperatures should continue through most of next week.

Snow in November? Well, last month many of us were asking “Snow in October?”. It will be possible for some periods of flurries or light snow showers behind the cold front late Saturday afternoon and Saturday night before the air dries out. No problems are expected. However, the best chance for this to occur will be at higher elevations (especially east of the city).

Bundle up, a cooler than normal period is on tap for the next 7 days!

David Glenn
Storm Track 9 Chief Meteorologist

Some rain has finally moved back into the Tennessee Valley and a typical November pattern will take hold through the end of the week. A series of systems will pass by from the west-southwest through Friday. This will provide us with some much needed rainfall, especially Wednesday Night and Thursday. A stronger cold front may again produce some rain late Friday Night and early Saturday. That front will also usher in some much colder air for the weekend.

Rainfall amounts should range from .50″-.75″ across our local region. The map below illustrates the expected rainfall amounts from Wednesday Evening through Thursday Evening. Also, take a look at the other maps below illustrating the temperature outlook for the next 6-10 days. Keep the sweaters handy, it will be cooler than normal especially this weekend.

(Click on each map for larger view)

David Glenn
Storm Track 9 Chief Meteorologist

A special thank you to the 4th grade class at Brown Academy in Chattanooga. I had the chance to visit the school Thursday. Thanks to Billy Campbell for the invitation, I had a great time!

David Glenn
Storm Track 9 Chief Meteorologist

The blue sky and sunshine is illuminating the spectacular Fall color across the Tennessee Valley. This set of pictures was sent in by Dawn and Mike Kropff. These views are from along Route 111 between Hixson and Dunlap. Enjoy!

(Click each for a larger view)

Thanks to Jerry Doss for this picture from the Bakewell area.

David Glenn
Storm Track 9 Chief Meteorologist

Instead of driving to my local voting precinct, I instead took an enjoyable 1 mile stroll to the voting booth. Along the way, the scenery was beautiful on this peak week of fall foliage.
(click each for a larger view)

David Glenn
Storm Track 9 Chief Meteorologist

A burst of fall colors is happening all across the Tennessee Valley. This should be the peak 7-10 days of color through the upcoming weekend. Some trees are lagging behind which might even extend some color through mid month. Here are some pictures that I took Monday morning while I was walking my dog. Enjoy!
(click each image for a larger view)

David Glenn
Storm Track 9 Chief Meteorologist

October 2008 was slightly warmer and drier than normal. The average temperature was 61.33 degrees which was just 0.7 degrees above normal. This was much different from last year. In 2007, the average temperature was 66.3 degrees which was 5.9 degrees above normal. So, 2008 was closer to what a normal October should be for us. 12 of the last 14 days of the month had below normal temperatures. We experienced our first freeze on the morning of the 29th when 30 degrees was recorded at Lovell Field. The warmest temperature was 85 on the 6th.

Rainfall was below normal which has been a common trend the past few months (and years!). October is typically the driest month of the year anyway. However, even with a dry month expected, 2008 was even drier. The final tally for rainfall was 2.69 inches which was 0.44 inches below normal. Compared to 2007, it was actually wetter than normal last year with 3.69 inches of rain.

So, as we turn the calendar to November, here is the latest outlook from the Climate Prediction Center. Overall, our region falls into the “equal chances” category for both temperature and rainfall. The temperature map does show the possibility of above normal temperatures across New England, with equal chances of below or above for the rest of the country. As for rainfall, above normal chances are possible across the middle Mississippi and Ohio Valley, but equal chances for the Tennessee Valley. (see maps below - click each to enlarge).

November is a transitional month as we get closer to winter. This means that we can expect wild swings in temperature from warm to cold and back to warm. This also means that as stronger cold fronts move in, our chance for severe weather typically increases. November is also known as the “second season” for severe weather locally. The spring months have a higher likelihood of severe storms, but the fall months, especially November comes in second. As always you can count on the Storm Track 9 Team to keep you posted!

I will have my Winter Forecast coming up by the middle of the month!

David Glenn
Storm Track 9 Chief Meteorologist