Monday, October 15, 2007

StormTrack 9's New Blog Location!


I want to thank everyone for reading the StormTrack 9 Blog at its current web location. Starting October 16th, a newly revamped Newschannel 9 web page will be unveiled. We are very excited about this, and I am sure you will be pleased to see the new layout and content of our web page. I have been striving to make the StormTrack 9 Blog and all of the weather content on our web page to be the best web site for local weather. With our new website and blog that commitment will continue. So, please update you Favorite's List and join us on the new Newschannel web page at www.newschannel9.com.

Wednesday, October 10, 2007

NOAA Winter Forecast Issued....La Nina = Warmer




With the first Fall chill on its way, NOAA is trying to warm things up with its release of the 2007-2008 Winter outlook. Their forecast is no surprise based on the La Nina conditions in the eastern Pacific. A large part of the country including the Tennessee Valley is expected to have warmer than normal temperatures (typical for a La Nina pattern). The Tennessee Valley is right on the borderline of being just above normal for rainfall and below normal. So, it could go either way. A few days ago I posted some research that I did on the local effects of La Nina. Overall, it usually does mean warmer than normal conditions for the season, but there will be some cold spells mixed in. Here is a reprint of that research:

La Nina is a global pattern that results from the cooling of the ocean water off the coast of South America. It is just the opposite of the El Nino pattern of warm water in the same region. The upwelling of water in the equatorial region off the South American coast leads to this effect. Now, El Nino and La Nina episodes are nothing new, both have been occurring at alternate periods for centuries. However, with each episode we are learning more about the global ramifications that take place. In simplest terms, a La Nina pattern usually equals mild and dry winters in the U.S. and increased hurricane activity in the western Atlantic. El Nino episodes usually relate to wetter patterns over the southern U.S and slightly decreased hurricane activity in the tropical breeding grounds of the Atlantic. Now, that is a broad scale view of the two patterns. With a developing La Nina, here is some research on how our local weather has been effected by past La Nina episodes.

I took a look at La Nina episodes that have occurred since 1980 and there were 5 of them. The most recent was in 2000-2001. Other years include, in order: '83-'84, '88-'89, '95-'96, '98-'99 and '00-'01. Each set of years had some differences as would be expected. But, there were some similarities. I will start with tropical weather. With the exception of '83-'84, each La Nina set of years had above normal tropical activity late in the season (mid Sept-November). The average was 4 September storms, 3 October storms and 1 November storm. There was also an average of at least 2 major hurricanes during the late part of the season. As for our local conditions during the time frame of October-March, here is what I found. Octobers were warmer and drier than normal. Novembers had near normal temperatures and above normal rainfall (yipee!). The December's during these years were quite interesting. Decembers average below normal for temperatures and slightly above normal for rainfall/snowfall. Snowfalls of 2.3 inches (2000) and 3.5 inches (1998) occurred. The months of January and February both had above normal temperatures with at or above normal rainfall. Some light snows occurred in the January years, but not as much in February. One month that really stood out was the month of March. In each La Nina year, March was cooler and drier than normal.

Only time will tell what transpires over the next 6 months. But, based on the averages, we could be looking at a milder, but slightly wetter than normal winter (December could be the cold month), followed by a cooler March. At the very least, the prospects of rain are looking a little better than last winter. We shall see how 2007-2008 turns out!

Tuesday, October 9, 2007

First Front Drier....Second Front Cooler

The gradual change to cooler than normal conditions is beginning to take place. The first front has moved through. This front is more of a dry front more than anything. So, for Wednesday, it will still be warm but a lot less humid. Afternoon temperatures on Wednesday should reach the lower 80s. A second cold front should move through Wednesday night and early Thursday. This front will bring a much cooler surge of air into the Tennessee Valley. Thursday should be breezy and cooler with afternoon readings in the upper 60s and a brisk north wind at 10-15 mph. Some clouds could also move in for Thursday afternoon. Morning low temperatures should drop into the middle 40s for Friday and Saturday morning. Temperatures should gradually warm back to near 80 by next Monday. The chance of rain still remains slim with the next chance probably not until next Tuesday.

Monday, October 8, 2007

Cooler Temps Should Begin Some Leaf Change



The peak of the fall foliage in the Tennessee Valley is still 3-4 weeks away. Typically, we can expect a the spectacular colors the last week of October and early November. Locally, some trees have shown some change, due in large part to the drought. Over the next few weeks, the combination of a lower sun angle and cooler nights should help begin the foliage change.

The images above were taken late Monday afternoon in the heart of the Great Smoky Mountains National park at Look Rock and Purchase Knob. The higher elevations will begin to have more noticeable change in foliage over the next 2 weeks. You can find a link to these 2 camera sights on the left margin of this blog page under "Dave's Weather Links"

Sunday, October 7, 2007

Cooler Weather Finally On the Way!

Sunday was another unseasonably warm (hot) day with temperatures near record levels. Monday should again be quite warm, er uh...HOT with highs in the upper 80s. Well, if you like cooler weather, you might be glad to know that cooler air is on the way. A cold front should slide through Tuesday creating a few showers. Cooler air will follow which should drop our afternoon readings into the 70s for Wednesday through Saturday. Morning lows should also be closer to normal in the lower 50s.

Tuesday, October 2, 2007

Home Stretch of the Hurricane Season


As the 2007 hurricane season enters its final 2 months, or the home stretch, it could remain active right up to the final day of November 30. If you have read some of my earlier posts, you know that the La Nina pattern could continue through the upcoming winter and spring. Such patterns have lead to active late season action in the tropics. Even today, we are watching an area of low pressure in the Gulf for any tropical development. Currently, that "low" is more of a cold core system, so it is not purely tropical but it could cause tropical-like rains and squalls along the coast. Right now, our chance of rain with this system looks low if at all, but we should see some more cloud cover. Now, late season tropical activity has on occasions brought us some heavy rain. So, with the higher than normal chance that the season could remain active, there still exists a chance for us to have some much needed rain. As always, only time will tell.

Here is a link to the updates hurricane forecast from Colorado State University (a very good article): Dr Gray October update

Thursday, September 27, 2007

Drought Effects on Fall Foliage





With October just around the corner, our expectations grow with the thought of the upcoming fall foliage. This year though, may be a tough one. The April freeze and continued drought conditions may not allow some leaves to even make it to the peak of the season in late October. The remaining leaves might even be delayed in changing due to the late season heat. Fall foliage is indeed hard to predict because of so many different weather conditions that can occur near the peak of the season. The peak is usually from late October to early November in the Tennessee Valley. In the higher elevations, the peak is usually in mid-late October. Here is a link to a very interesting article which sheds some light on what could occur with the fall foliage this year.

http://www.herald-citizen.com/NF/omf.wnm/herald/news_story.html?rkey=0046029+cr=gdn

Thursday, September 13, 2007

Thank You Humberto!


In so many of my past posts, I mentioned the fact that it would take a few tropical systems to give us some much needed rain. Humberto is just what we needed. Now, of course, I hate to see anyone experience damage like the folks did on the Texas/Louisiana coast, but the inland rain is welcome. The heaviest rain will be to our south over central Alabama and Georgia, but even here in the Tennessee Valley we should see rainfall amounts from 1/2 inch to an inch in many spots. A few areas could see more, especially south. A cold front should sweep in late Friday pushing the rain out of here and setting the stage for a drier and cooler weekend. Clouds might linger early Saturday, but sunshine should return for the afternoon. with a brisk north wind, high temperatures should only be near 80 and morning lows Sunday in the middle 50s. Most of next week should be dry again, so Humberto, we say thank you!

Tuesday, September 11, 2007

La Nina Effects on the Tennessee Valley



I have used the term "La Nina" in several past posts especially relating to the tropical season. With NOAA making it official that a La Nina pattern should persist for at least the next 3 months, I thought I would do a little research on the effects a La Nina pattern could have on our local weather.

La Nina is a global pattern that results from the cooling of the ocean water off the coast of South America. It is just the opposite of the El Nino pattern of warm water in the same region. The upwelling of water in the equatorial region off the South American coast leads to this effect. Now, El Nino and La Nina episodes are nothing new, both have been occurring at alternate periods for centuries. However, with each episode we are learning more about the global ramifications that take place. In simplest terms, a La Nina pattern usually equals mild and dry winters in the U.S. and increased hurricane activity in the western Atlantic. El Nino episodes usually relate to wetter patterns over the southern U.S and slightly decreased hurricane activity in the tropical breeding grounds of the Atlantic. Now, that is a broad scale view of the two patterns. With a developing La Nina, here is some research on how our local weather has been effected by past La Nina episodes.

I took a look at La Nina episodes that have occurred since 1980 and there were 5 of them. The most recent was in 2000-2001. Other years include, in order: '83-'84, '88-'89, '95-'96, '98-'99 and '00-'01. Each set of years had some differences as would be expected. But, there were some similarities. I will start with tropical weather. With the exception of '83-'84, each La Nina set of years had above normal tropical activity late in the season (mid Sept-November). The average was 4 September storms, 3 October storms and 1 November storm. There was also an average of at least 2 major hurricanes during the late part of the season. As for our local conditions during the time frame of October-March, here is what I found. Octobers were warmer and drier than normal. Novembers had near normal temperatures and above normal rainfall (yipee!). The December's during these years were quite interesting. Decembers average below normal for temperatures and slightly above normal for rainfall/snowfall. Snowfalls of 2.3 inches (2000) and 3.5 inches (1998) occurred. The months of January and February both had above normal temperatures with at or above normal rainfall. Some light snows occurred in the January years, but not as much in February. One month that really stood out was the month of March. In each La Nina year, March was cooler and drier than normal.

Only time will tell what transpires over the next 6 months. But, based on the averages, we could be looking at a milder, but slightly wetter than normal winter (December could be the cold month), followed by a cooler March. At the very least, the prospects of rain are looking a little better than last winter. We shall see how 2007-2008 turns out!

Thursday, September 6, 2007

Weekend College Football Weather





Ah yes, the first week of college football really wet our appetite for the second week of action this weekend. So, for all you tailgating fans, here is a look at the weather conditions for area teams Saturday.

UTC at Jacksonville State (3:30pm) - Partly Sunny 90

Southern Miss at Tennessee (7pm) - Partly Cloudy 84

South Carolina at Georgia (5:45pm) - Partly Sunny 90

Alabama at Vanderbilt (11:30am) - Partly Sunny 84

Samford at Georgia Tech (1:30pm) - Partly Sunny 89

South Florida at Auburn (8pm) - Partly Cloudy 85

Sewanee is off this week

Tuesday, September 4, 2007

Felix Ashore.....Another System Closer to U.S. to Watch



Major Hurricane Felix roared ashore at Category 5 strength along the northeast coast of Nicaragua close to the Honduras border. Felix strengthened during the predawn hours as it went through an Eyewall Replacement Cycle. During this cycle, the sustained wind initially dropped late yesterday, but then rapidly strengthened during the completion of the cycle just before landfall. This marks the second category 5 landfall this season. Both Dean and Felix fed off nearly perfect surface and upper level conditions to pull off such feats. There is a lot of talk about the warm water being the main ingredient. Well, it is one important ingredient, but not the only one. The Caribbean waters are always going to be warm, it is a low latitude body of water. So, yes, during the height of the hurricane season, you can bet on the warmest water of the season. Upper atmospheric conditions play a huge part in a storms survival. During both Dean and Felix, a strong ridge of high pressure was situated north of the storm. The same ridge of high pressure that brought our region the extreme heat. The strength of that "high" allowed Dean first of all to be well ventilated and lacking of any shear to disrupt its development. A slightly weaker, but otherwise strong ridge again is positioned over the US southeast and Gulf which steered Felix and created similar perfect conditions for development. The developing La Nina conditions off the western South America coast plays a role in these upper level conditions. La Nina is the opposite of El Nino. It is a cooling of the waters off the South American coast which also affects global weather patterns and occurs on intervals opposite of El Nino. When a La Nina is developing or is in place, we expect hurricane conditions to be above normal. This occurs because La Nina creates a lack of wind shear in the tropical development region. With a lack of shear, storms can more easily develop and strengthen. During an El Nino episode, wind shear increase in the tropical development region and that can serve to prevent development or help weaken a developed storm. So, year in and year out, the Caribbean waters are plenty warm, but it's the upper level factors that go a long way in determining the outcome of a storm.

Another area to watch for development is off the southeast US coast. Currently, it is a non tropical low. But, should it continue drifting off the coast around the region of the warm, Gulf Stream waters, the "low" could become a warm core, or tropical system. Some computer model guidance shows this system drifting for 24-48 hours before gaining some strength and backing west toward the coast. So, as we enter the peak of the hurricane season there is a lot to watch.

Sunday, September 2, 2007

Major Hurricane Felix Threatens Southern Caribbean



Felix is now a major hurricane reaching category 5 strength!

Hurricane Felix is slowly creeping westward through the southern Caribbean Sea. Aruba is feeling the effects of the south side of the storm. Felix should continue a westward motion gaining a little latitude north through early next week. Belize could be the next landmass Felix affects next week.
Elsewhere in the tropics, there are 2 areas being monitored. The first is off the Georgia coast. This is a an area of low pressure that is left over from a decayed frontal zone. With very weak upper level support, systems such as these have to be closely watched for signs of any tropical development. It should slowly drift east. The second area to watch is between the US and Africa. This tropical wave is not showing immediate signs of development, but could over the next few days. September is the peak month of hurricane season, with the peak day of the season on the 10th. The "peak weeks" of the season continue through October 15th. The season does not end until November 30.

Tuesday, August 28, 2007

Hurricane Katrina....My Look Back




At times it feels like it's been longer, but other times it feels like yesterday. Today marks the second anniversary of Hurricane Katrina. On August 29, 2005 I was serving as Chief Meteorologist at WPMI-TV Mobile/Pensacola. We were in the midst of our wall to wall coverage of the storm that began 2 days earlier. Katrina would be the third major hurricane to arrive near our doorstep during one calendar year. Hurricane Ivan pounded our local coastline the September before and Hurricane Dennis rubbed salt in Ivan's wounds 2 months earlier. Of all the evacuation plans executed before, this one was the biggest.
My wife and children evacuated for the third time in less than a year. I sent them on their way the day before Katrina struck to seek refuge at my inlaws in Ft Payne, AL. As a meteorologist, I had some long hours ahead of me and I needed as much time as possible to prep our house and then be ready for the LONG work day(s) ahead. Having my family evacuated was a huge relief. I knew they were safe, and with my house secured with the storm shutters, I could then focus squarely on my job. Katrina was no surprise, we saw it coming and knew that once the storm passed over the Gulf Loop Current, its strength would grow. Mobile was not going to be the point of landfall, but it was going to be on the dangerous east side of the hurricane which would bring an incredible storm surge and high wind.
Sunday, August 28, our broadcast schedule required each meteorologist to work a 12 hour shift. So, I had a whole 1/2 day on the air, the other 12 hours spent prepping for the storm, forecasting, and trying to catch a nap. Most of that day was sunny and hot with intermittent periods of thunderstorms. To their credit, most Mobilians wasted no time getting ready for Katrina's visit. By sundown, all preparations came to a end and the worst of Katrina was nearing our doorstep. It was one of those days where I hoped my forecast would be wrong. The forecast included a 10-14 ft storm surge with wind exceeding 100mph.
Monday, August 29th is a day I will never forget. Katrina made the first landfall along the coastal region of Louisiana around 6am and then the second landfall along the Louisiana/Mississippi border. Mobile never noticed the difference. Since before 6am and through mid afternoon, the pounding wind and rain was being unleashed. All the while, the waters of Mobile Bay were being pushed into the city streets. The resulting storm surge brought a near record level of 13ft of water. Our broadcast plans were interrupted at about 9am when the station's generator caught on fire. This resulted in complete failure of the electrical system. During hurricane broadcasts, we would simulcast with area radio stations because so many people would lose power during the storm. With no power at the television building, we had to drive toward downtown to the radio building to continue our broadcasts. It was true "white knuckle" driving for a while with debris covered roads, and yet more airborne debris flying around. We spent the next 13 hours on the radio through midnight before a shift change. By midnight, the storm had passed and all that was left was DARKNESS. I attempted to drive home and what would normally be a 10 minute drive, took nearly an hour. Debris covered roads and no street lights made for a trip I will never forget. Once I got home, I was relieved that the house was intact except for the shingles sheared off the roof. I felt fortunate, because so many people were left homeless along the Alabama, Mississippi and Louisiana coast.
There are certain levels of exhaustion and emotion that I found myself going through before and after the storm. There is the physical exhaustion of boarding up and preparing your home while balancing the hours of my job which were quite demanding. Then, there is the mental exhaustion because of the anxiety building up before and during the storm. Emotional exhaustion would rise and fall before, during and after the storm. Telling your family goodbye and seeing your children leave with tears in their eyes because Dad has to stay behind...that's not easy. Seeing members of your community lose everything is tough to watch as you sit in a house that is still standing. And, it was not just the local community of Mobile. Areas to the west along the Mississippi and Louisiana coast saw total devastation. Many of those people migrated east toward Mobile for help. What still haunts me to this day are the dazed and lost expressions on their faces. They needed food, water and shelter. They had reached the point of desperation. Fortunately, the Mobile community provided their needs. There were long lines at grocery stores, and no gasoline anywhere for miles. Power was not restored for days, and trust me it was VERY hot those days after Katrina.
State and local officials in Alabama responded immediately and our region was spared the finger pointing and blame game issues that occurred to our west in Louisiana. I witnessed that aspect like many of you did via television reports. It was a totally different type of damage level with levee flooding than the quick in and out storm surge flooding we had on the Alabama coast. Their flooding would last much longer. the US Coast Guard headquarters for the Gulf region is in Mobile. They were flying rescue missions in MS and LA nonstop for days even during the storm. The sound of the helicopters filled the skies constantly.
During the 16 years of my career in meteorology, I hope I never see another year like 2004-2005. Ivan, Dennis and Katrina was enough experience for a lifetime. Despite the devastation I was thankful to be a part of a community getting back on its feet. I saw the worst in mother nature, but the best in mankind.
As I write this now during the heart of the 2007 hurricane season, I can say with 110% certainty, that I am glad to be back home in the Tennessee Valley :)

Pictures:
1: Landry's Restaurant - Biloxi, MS
2: West side of Mobile Bay, AL
3: Storm Shutters on our Mobile, AL home

Eclipse Photos....Showers Return!




A very big "thank you" to Kathryn Harris of Hixson for sending in her photos of this morning's lunar eclipse. The eclipse was seen low on the western horizon, which may have been blocked by the local mountains and ridges for some of you. Those who did see it saw a nice treat just before sunrise. In case you missed it, don't worry, you will get another chance coming up in February.

Welcome back rainfall!!! Granted, the storms were just scattered in nature, but those if us that did experience rain received almost an inch of rain. The official reading at Lovell Field was 0.94 inches, but only 0.21" at the WTVC studios. before the storms arrived the temperature peaked out at 95 degrees. That means that 24 of the past 25 days have been 95 or higher...whew! Temperatures should take a break the next few days as we should see a daily round of afternoon t-showers. The best coverage should come on Thursday with a front slowly moving in.

Monday, August 27, 2007

Total Lunar Eclipse Tuesday Morning





You will have to get up early to enjoy this celestial treat. With a full moon in place, the moon will pass in the shadow of the earth which will block the sun's rays from reaching the moon. The end result will be a darkened, rusty colored moon which will be visible for almost 2 hours. The partial eclipse will begin at 4:51am, then enter the total eclipse phase from 5:52am-7:22am. The end partial phase will take place at 8:24am. unlike a solar eclipse, you do not need special tools or eye guards to view it. It will be visible with the naked eye, and even better through a telescope lens.

As I mentioned in an earlier posting, the Mars Email Hoax continues to generate calls and email. This Email sounds impressive, but it is a hoax. I am only repeating this because tonight is the night the Email mentioned. And, I just want everyone to realize that the rusty colored moon tonight is indeed the moon....and not Mars.

Friday, August 24, 2007

Another Record Falls


102 was the official high temperature in Chattanooga Friday which just nudged out the old record of 101 set in 1968. The record streak of now 21 days 95 degrees or higher continues and we are still on pace for the hottest August ever with an average temperature of 86.2 degrees.

Thunderstorms made a return to the area. Some were severe with marble size hail reports from Cleveland and heavy rain in many spots. The rain helped cool things off for some of the high school football games, but other game sites were still hot and dry. The pattern that we saw Friday should repeat itself for Saturday as thundershowers once again pop up. Afternoon temps should stay below record levels Saturday, but still be plenty hot in the upper 90s.

Thursday, August 23, 2007

Only the Records Are Falling!

Not only was a daily record high set in Chattanooga, it was within 1 degree of tying the all time record high. 105 was recorded at Lovell Field at 2:26pm which surpassed the old record of 102 set in 1968. The all time record high is 106 set on July 28, 1952. We are also seeing other records fall. We are still on pace for the hottest August on record with an average temperature of 86 degrees far above the current record holder of August 1993 with an average of 82.5. We have experienced 20 straight of temperatures above 95. The old record was 18 days in late August and early September of 1993. We could set another record Friday with highs around 100. The record is 101, so another record is within reach.

Wednesday, August 22, 2007

Yet Another Record High!

Once again, record heat was experienced across the Tennessee Valley. The recorded high temperature at Lovell Field was 103 degrees, which surpassed the old record of 100 set in 1983. We are still on pace for the hottest August on record with an average temperature of 85.9 degrees. The current record belongs to August 1993 with an average of 82.5, so we are currently well above the number. August 2007 could also go down as the hottest month ever recorded in Chattanooga.

Now for some "cool" thoughts to ease the heat:

- Today's Record Low: 55 (1956)....It is possible to actually have cooler weather this time of year!

- Autumn is only 31 days away

- The average date of the first frost is October 21st (just 2 months away)

- Yesterday's high temperature at Mt. LeConte, TN (elevation 6600 ft) was only 72.

Tuesday, August 21, 2007

Felix Forming?




August 15-October 15 is typically the busiest 2 months of the hurricane season and this year has started heating up right on time. Dean reached the Top 10 list of strongest recorded hurricanes before plowing into the Yucatan. Cancun was spared the worst with Chetumal to the south taking the brunt of the storm. Dean should move back over water in the southern Gulf (Bay of Campeche) before making a second landfall. The second landfall in Mexico will be far less severe than what occurred on the Yucatan. As Dean begins moving away, another system is being watched well east of the Bahamas. A tropical wave interacting with an upper low is tightly clustering t-storms and upper level conditions are beginning to improve for some development over the next couple of days. The NAM, North American Model puts this system near the Bahamas over the weekend with a continued westerly movement. The tropical model suite (see image above) also favors a westerly path with some slow development. So, "Felix" could be on the horizon.

Dean Makes Landfall

HURRICANE DEAN ADVISORY NUMBER 33
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042007
400 AM CDT TUE AUG 21 2007

...CATEGORY FIVE HURRICANE DEAN MAKES LANDFALL ON THE EAST COAST OF
THE YUCATAN PENINSULA OF MEXICO...

AT 400 AM CDT...0900 UTC...THE GOVERNMENT OF MEXICO HAS REPLACED THE
TROPICAL STORM WARNING AND HURRICANE WATCH WITH A HURRICANE WARNING
FROM WEST OF CHILITEPEC TO VERACRUZ MEXICO.

REPORTS FROM AN AIR FORCE HURRICANE HUNTER PLANE INDICATE THAT THE
EYE OF DEAN MADE LANDFALL ON THE EAST COAST OF THE YUCATAN
PENINSULA NEAR COSTA MAYA OR MAJAHUAL AROUND 330 AM CDT. THIS
LOCATION IS ABOUT 40 MILES...65 KM...EAST-NORTHEAST OF CHETUMAL
MEXICO

MAXIMUM SUSTAINED WINDS ARE NEAR 165 MPH...270 KM/HR...WITH HIGHER
GUSTS. DEAN IS A CATEGORY FIVE HURRICANE ON THE SAFFIR-SIMPSON
SCALE. ALTHOUGH SOME WEAKENING IS FORECAST AS DEAN CROSSES THE
YUCATAN PENINSULA...DEAN IS EXPECTED TO MAINTAIN HURRICANE STRENGTH
THROUGHOUT THE NEXT 24 HOURS.