This note from the NWS concerning the Birmingham NEXRAD radar:

...BIRMINGHAM NWS DOPPLER RADAR WILL BE DOWN THIS WEEK FOR AN UPGRADE...

RADAR TECHNICIANS WILL BE WORKING ON THE BIRMINGHAM (KBMX) DOPPLER RADAR THIS WEEK FOR A SIGNIFICANT HARDWARE UPGRADE. THE RADAR WAS TAKEN OFF LINE ON MONDAY MORNING MARCH 6. THE UPGRADE WILL RESULT IN A SIGNIFICANT IMPROVEMENT TO THE PERFORMANCE AND PRODUCTS GENERATED BY THE RADAR. IN ORDER TO COMPLETE THE NECESSARY CHANGES...THE RADAR WILL NEED TO BE DOWN FOR MOST OF THE WEEK...BUT SHOULD BE BACK ON LINE BY FRIDAY MARCH 10. THE BIRMINGHAM NWS OFFICE WILL NOT HAVE THE OPTION TO BRING THE RADAR BACK ON LINE IN THE EVENT OF INCLEMENT WEATHER. MAXWELL (KMXX)...COLUMBUS (KGWX) AND HYTOP (KHTX) RADARS SHOULD SERVE AS ADEQUATE BACKUPS DURING THIS SCHEDULED OUTAGE.

The good news is that the ABC 33/40 Pinpoint Doppler radar atop Double Oak Mountain in northern Shelby County is running normally, and will give us an excellent view of the strong to severe thunderstorms that are expected to impact Alabama Thursday afternoon and Thursday night.

You can access single images here:

http://www.abc3340.com/weather/doppler.html

And, watch the radar live in streaming video from the link on our main weather page:

http://www.abc3340.com/weather/

When the live stream comes up, you can move your cursor over the video box and icons will pop up that give you the option to view the radar in the "Real Player", which allows you to make the video full screen, or any size you like. We also use this stream when we have "wall to wall" tornado coverage going on. This will prove to be extremely helpful during this severe weather season.

* 94 was the high in Wink, Tex., today, the national high

* 10 below zero was the coldest in the Lower 48 at Saranac lake, N.Y.

* 44 below zero was the wind chill in Point Hope, Alaska at 9 tonight (CST)

* 12 is the number of Severe Thunderstorm Warnings so far late today and tonight mainly in Oklahoma, Missouri, Iowa and Nebraska

* 2 to 5 is how many inches of snow will accumulate in NE Minnesota tonight

* 6 to 10 inches is how much snow is expected in the mountains of Western Colorado and SE Utah

* 140 days in a row is how long it has been with not a drop of rain in Phoenix

BULLETIN - EAS ACTIVATION REQUESTED
CHILD ABDUCTION EMERGENCY
TENNESSEE BUREAU OF INVESTIGATION NASHVILLE TN
RELAYED BY NATIONAL WEATHER SERVICE NASHVILLE TN
604 PM CST TUE MAR 07 2006

THIS IS A CHILD ABDUCTION EMERGENCY RECEIVED BY THE
TENNESSEE BUREAU OF INVESTIGATION

A STATEWIDE AMBER ALERT HAS BEEN ISSUED BY THE SUMNER COUNTY
SHERIFFS DEPARTMENT FOR SEVEN YEAR OLD DAKOTA KANE...A WHITE MALE
THREE FEET TALL AND WEIGHS SIXTY FIVE POUNDS BLOND HAIR BLUE EYES
WEARING BLACK WINDPANTS AND A GRAY LONGSLEEVE HARLEY DAVIDSON SHIRT
AND FIFTEEN YEAR OLD CHARLES PAUL JR...A WHITE MALE FIVE FOOT ELEVEN
INCHES TALL AND WEIGHS ONE HUNDRED AND THIRTY FIVE POUNDS BROWN HAIR
AND BLUE EYES. HE WAS WEARING A CAMO JACKET WITH A WHITE SHIRT.
THEY WERE TAKEN BY DANIEL KANE...A WHITE MALE FIVE FOOT EIGHT INCHES
AND WEIGHS ONE HUNDRED AND SIXTY POUNDS. HE IS DRIVING A STOLEN TWO
THOUSAND AND FIVE BLACK FORD FOCUS WITH TENNESSEE TAG S J M 632. HE
IS ARMED WITH TWO BLACKHAWK RUGER PISTOLS. HE TOOK THE VEHICLE AT
GUNPOINT AND IS CONSIDERED ARMED AND DANGEROUS DO NOT APPROACH
PLEASE CONTACT T B I AT ONE EIGHT HUNDRED T B I FIND.

The Tuesday afternoon map discussion video is on the server:

http://beta.abc3340.com/weather/video.hrb

This will be a busy discussion. And a little long...

TOMORROW: Beautiful day. Partly sunny and warmer; look for low 70s.

SEVERE WEATHER THREAT: We are still looking at the possibility of an outbreak of severe thunderstorms across the Deep South, including much of Alabama, Thursday afternoon and Thursday night as a vigorous early spring storm system approaches.

Severe storms should increase during the day Thursday to the west of us, over Mississippi, West Tennessee, North Louisiana, and East Arkansas. Some of the severe storms could ease into the western part of Alabama by mid to late afternoon.

Lets look at some of the severe weather parameters for Birmingham valid for 6:00 p.m. local time Thursday:

Surface based CAPE: 878
Lifted Index: -2.9
0 to 3 km SRH (Storm Relative Helicity): 491
SWEAT Index: 411
850 mb wind speed: 68 knots

We also note the 0 to 1 km EHI (Energy Helicity Index) peaks at 3.7 around Smith Lake at 6:00 p.m. EHI values greater than 2 are often associated with tornado outbreaks. One paper at the Southeast Severe Storms Symposium this past weekend suggested EHI is a very useful severe weather parameter for "Dixie Alley".

I get many e-mails asking about terms we use here... I refer all of you to the weather glossary here:

http://www.srh.noaa.gov/oun/severewx/glossary.php

And, a helpful look at various severe weather parameters here:

http://www.crh.noaa.gov/lmk/soo/docu/indices.php

What does all of this mean?

I still think we will be dealing with a squall line Thursday night sometime between 6:00 p.m. and midnight, with the potential for damaging wind along the line. The lower wind fields are screaming with this system, and even with no storms involved winds could easily gust to 30 mph. Maybe higher along ridge tops.

Some of the 12Z data also suggests some potential for a few isolated storms ahead of the line over West Alabama Thursday afternoon (3:00 to 6:00 p.m.)... these would have the potential to become supercells and produce tornadoes.

The big question is instability... the 12Z models have the numbers coming in a little higher (a more unstable atmosphere). You really want to see dewpoints of 65 or higher for a classic spring outbreak here; I think dewpoints on Thursday evening will be closer to 60. Early season systems often are a little lacking in the thermodynamic department. But, the values we see now certainly support the chance of severe storms.

SO... once again, we are now looking at potential for severe storms across West Alabama Thursday afternoon from 3:00 until 6:00 p.m. (mainly west of I-65)... some potential for isolated tornadoes there. Then, all of the state will deal with a fast moving squall line from about 6:00 p.m. until midnight. The storms should weaken a bit as they move into more stable air over East Alabama, but even in places like Anniston and Gadsden some strong winds will be possible.

We will be updating our thoughts here on the blog... so stay tuned.

THE WEEKEND: As I mentioned here this morning, we will need to include the chance of a few showers and storms over the weekend. No wash out, but a moisture axis will remain parked over Alabama, and a disturbed southwest flow aloft will bring showers or storms from time to time. Severe weather is not likely, and the sun should be out at times. If we see a decent amount of sun, we might be close to 80 Saturday and Sunday afternoon.

NEXT WEEK: Model mumbo jumbo continues. The 12Z GFS now shows the southwest U.S. trough coming out in a number of pieces again next week. I am not sure this is correct; I think the 06Z run was much more realistic. I still think we might have a severe weather threat in the Tuesday-Wednesday time frame next week, followed by a sharp late season cold snap over the latter half of the week (Thursday-Friday). But, confidence in details is very small with all of the model madness. One way or another it should be a very interesting week.

RADAR ISSUES: The Birmingham NWS NEXRAD system will be down this week (maintenance)...with active weather approaching I remind you ABC 33/40 owns and operates a C-Band radar atop Double Oak Mountain in northern Shelby County (Pinpoint Doppler Radar)... and it will be up and running through the event. Lots of TV stations use NWS NEXRAD data and call it "their own"radar. We have the luxury of using both our own system, and NEXRAD!

You can access single images here:

http://www.abc3340.com/weather/doppler.html

And, watch the radar live in streaming video from the link on our main weather page:

http://www.abc3340.com/weather/

When the live stream comes up, you can move your cursor over the video box and icons will pop up that give you the option to view the radar in the "Real Player", which allows you to make the video full screen, or any size you like. We also use this stream when we have "wall to wall" tornado coverage going on. This will prove to be extremely helpful during this severe weather season.

KIDCAM: Sure enjoyed seeing the little ones today at Our Lady of Lourdes school in Huffman... watch for them on the KIDCAM today at 5:00 on ABC 33/40 News!

I will have the next map discussion video posted by 7:00 a.m. tomorrow... watch for updates here on the blog as we get closer to the Thursday/Thursday night event!

The Tuesday morning map discussion video is on the server:

http://beta.abc3340.com/weather/video.hrb

Sure looks like mid-March will serve up a wide variety of weather here in Alabama this year, as usual.

Lets break it down in timeline fashion:

TODAY/WEDNESDAY: Very nice weather today. Ample sunshine, cooler, with highs in the low 60s. Tomorrow will be dry and warmer as we head back into the low 70s.

SEVERE WEATHER DISCUSSION FOR THURSDAY AFTERNOON/NIGHT: Severe storms still look likely for the Deep South as a vigorous upper air system comes out of the southern plains. SPC has a large slight risk area on Thursday from the Gulf Coast to the Ohio River, including all of Alabama.

The most impressive part of the system is the wind field in the lower levels; the NAM runs the 850 mb (around 5,000 feet) speed to 68 knots over Birmingham Thursday afternoon. This screaming low level jet will mean a windy day on Thursday, with winds at the surface possibly gusting to 30 mph even with no storms involved.

As usual in an early season system, the amount of instability is in question. The 06Z NAM has a max surface based CAPE value here of only 330 j/kg. I think that is a little on the low side, and we have seen values to almost 1000 on other runs.

I still think our primary threat will be from damaging straight line winds along a squall line that races through here. The models seems to be a little faster now, and we will adjust the timing a bit in our forecast. It now looks like the greatest risk of severe weather in Alabama will come from about 4:00 p.m. Thursday until 2:00 a.m. (early Friday morning).

Guess we can't rule out a few isolated tornados here, but it seems the greatest tornado threat would be northwest of Alabama Thursday afternoon... places like North Mississippi and West Tennessee.

With any thunderstorm event in Alabama, you know our slogan: "expect the unexpected". So, watch for changes in this forecast here on the blog as we get closer to the event.

THE WEEKEND: I was probably too early in downplaying the chance of rain over the weekend yesterday (maybe too stupid. The new model runs hang up a surface boundary around here on Saturday and Sunday, and we will need to mention some chance of showers or storms on both days. No wash-out, but be aware that a passing shower or two is certainly possible.

NEXT WEEK: I think the 06Z GFS has a great handle on coming attractions next week. The big trough in the southwest U.S. lifts out, and brings another risk of strong to severe storms around Tuesday (March 14). Then, a pretty good late season cold snap is ahead for the latter half of next week. How cold? First guess would highs in the 50s and lows in the 30s. Maybe a day where we don't get out of the 40s. And, when we go clear and calm a good freeze seems likely toward the end of the week or the following weekend.

WESTERN NOTES: Check out that cold upper low out west over the weekend. Maybe a few snow flakes for the Los Angeles basin? Our pals in Flagstaff might also finally see some overdue snow (one of our affiliate radio stations covers Flagstaff and I forecast weather out that way as well).

TODAY: Will be out in Huffman today seeing the kids at Our Lady of Lourdes school... will be back in the office for the afternoon video which will be posted by 3:30 this afternoon. Enjoy the day!