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Another Look At Tomorrow

| 9:36 pm April 24, 2015

Some notes on what to expect in Alabama during the next 24 hours…

OVERNIGHT: Rain will increase after midnight as a warm front lifts northward; some heavy rain is possible in spots, and thunderstorm intensity will also increase as higher dewpoints advect into North Alabama from the south.

We are still looking at two main windows for severe storms tomorrow…

FIRST ROUND: Storms between 4:00 and 7:00 a.m. could be strong to severe as we get into the warm sector of the storm system approaching from the west. Below is the HRRR model, valid at 5a CDT…

hrrr_ref_birmingham_10

The main threat will come from strong straight line winds and hail, but an isolated tornado is not out of the question.

This first batch of storms will exit the state by mid-morning, and many of the midday hours will be rain-free. The sun should break out at times, and we rise into the low 80s.

SECOND ROUND: This is a more difficult forecast, but there is as chance that new, scattered storms will begin to form by 3:00 p.m… with the risk extending through about 9:00 p.m. It is important to note that it won’t rain everywhere tomorrow afternoon due to the scattered nature of the storms. However, where the storms develop, they should become severe quickly, and will have potential for hail, strong straight line winds, and a few isolated tornadoes.

Interesting to note the new run of the high resolution NAM model shows little development tomorrow afternoon.

hires_ref_birmingham_24

The chance of severe storms developing tomorrow afternoon will simply depend on the state of the atmosphere after the overnight storms, and the degree of instability we see during the day. The best combination of dynamic lift, instability, and shear will be along and east of I-65, although we certainly can’t rule out a storm on the western side as well. But, there is also a chance very few storms will fire up. We will just have to wait and watch.

BIRMINGHAM NOAA WEATHER RADIO: Unfortunately, the Birmingham NOAA Weather Radio transmitter is still down… so we recommend using a smart phone app like MyWarn or WeatherRadio by WDT as a good backup. You can also change the frequency on your weather radio to Mt. Cheaha (162.475) or Tuscaloosa (162.40).

We will have more updates through the night… stay tuned…

Rain/Storms Move In Tonight

| 3:41 pm April 24, 2015

ACTIVE SETUP AS THE WEEKEND BEGINS: Clouds will thicken across Alabama over the next few hours, and rain will move into West Alabama this evening as a warm front begins to push northward. We expect a good rain/thunderstorm event overnight, with the heaviest and most widespread rain along and north of I-20. Rain amounts tonight will be in the 1/2 to 1 inch range, we will monitor the storms for severe weather potential. Higher dewpoints and unstable air will advect up into the state early tomorrow.

TOMORROW: SPC has adjusted their outlook tomorrow a bit; now the standard “slight” risk of severe weather is in place north of a line from Russellville to Alabaster to Opelika… a “marginal” risk south of that line. The “enhanced” risk is north of Alabama, for parts of Tennessee and Kentucky.

day2otlk_1730

Surface based CAPE values will rise to near 3,000 j/kg tomorrow afternoon, the most unstable air we have seen all year. EHI (Energy Helicity Index) values peak at over 3 units over Northeast Alabama tomorrow afternoon. Wind fields and shear values are not overwhelming, but they are certainly supportive of the potential for a few severe thunderstorms.

Here are the important things to know about tomorrow…

*I can’t rule out a few early morning severe storms as the big rain mass moves out of Alabama… in the 4:00 to 7:00 a.m. time frame. Main risk will be from hail and gusty winds, although an isolated tornado is not completely out of the question.

hrrr_ref_birmingham_16

*Rain and storms will end from west to east early tomorrow morning, and most of the rain should be in Georgia by 9:00 a.m.

*The middle of the day, and a decent part of the afternoon will be dry, with some sun at times. Temperatures will rise into the low 80s.

*Scattered storms will form tomorrow afternoon and early tomorrow night, and where those storms develop they could be severe. Understand, not everyone will have a thunderstorm tomorrow evening, but where they form they could become severe quickly.

*The main window for scattered severe storms will come from about 3:00 p.m. until 9:00 p.m., and the better chance of them will be along and east of I-65, where dynamic support will be higher.

*The risk of severe weather over the southern half of the state is fairly low.

Everyone should have a way of receiving severe weather watches and warnings if they are needed.

BIRMINGHAM NOAA WEATHER RADIO: The Birmingham system remains down; the NWS is working as hard as they can to get service restored, but if you are in the Birmingham metro, understand you won’t get warnings via Weather Radio until the transmitter is back. A good alternative is a smart phone app like WeatherRadio by WDT, or MyWarn.

SUNDAY: SPC has a “marginal” severe weather threat for the southern part of Alabama, south of a surface boundary… we believe the northern half of the state will be dry with a partly sunny sky and a high around 80 degrees.

NEXT WEEK: Monday will stay dry; rain returns Tuesday afternoon through Wednesday, but this system won’t bring a severe weather threat since a relatively weak surface low will pass south of us, near the Gulf Coast. For now it looks like a harmless spring rain event. Drier air returns Thursday and Friday. See the Weather Xtreme video for maps, graphics, and more details.

WEATHER BRAINS: Don’t forget you can listen to our weekly 90 minute netcast anytime on the web, or on iTunes. This is the show all about weather featuring many familiar voices, including our meteorologists here at ABC 33/40.

CONNECT: You can find me on all of the major social networks…

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I had a great time today visiting with the kids at Sulligent Elementary School in Lamar County… be looking for them on the Pepsi KIDCAM today at 5:00 on ABC 33/40 News! My next Weather Xtreme video will be posted here by 7:00 a.m. Monday… Brian Peters will have the video updates tomorrow and Sunday. And, we will post frequent updates on the Alabama weather situation over the next 24 hours, so stay tuned…

Severe Weather Risk Tomorrow

| 6:20 am April 24, 2015

COOL START: Another cool April morning across North Alabama; Fort Payne reports 37… our Skywatcher at Black Creek (just northeast of Gadsden), Vic Bell, reports 39, and Cullman is at 42. We rise into the 70s this afternoon with intervals of sunshine. The bulk of the day will be dry.

WET TONIGHT: A large mass of rain and storms, associated with a northward moving warm front, will overspread the state. The latest high resolution HRRR model hints that the rain could begin this evening, in the 5:00 to 7:00 time frame. Expect periods of rain and a few thunderstorms through the night; the rain could be heavy at times, and a strong storm is certainly possible. SPC has a “marginal” risk of severe storms into the western half of Alabama late tonight, but most of the storms will be elevated, and the risk of organized severe weather is fairly small (but not zero). Rain amounts of 1/2 to 1 inch look likely overnight.

SEVERE WEATHER THREAT TOMORROW: We have higher confidence in the scenario for tomorrow; SPC maintains the standard “slight” severe weather risk for much of the state, with an “enhanced” risk over far North Alabama and up into Tennessee.

day2otlk_0600

The air will be very unstable tomorrow afternoon, with surface based CAPE values exceeding 3,000 j/kg in spots over North Alabama. Low level helicity values will be supporting of rotating updrafts, and lapse rates hint that some large hail is possible in stronger storms that form late in the day.

Here is what to expect….

*The overnight batch of storms will end early in the day, and a decent part of the mid-day hours will be dry with the sun breaking out. Temperatures will rise into the low 80s, maybe even mid 80s in parts of West Alabama by afternoon.

*New storms will begin to form in the 3:00 to 6:00 p.m. time frame. It is important to note that not everyone will see an afternoon or evening storm; they will be scattered in nature.

*Where storms do form, they would be severe, with potential for large hail, damaging winds, and a few isolated tornadoes.

*The tornado threat is highest across the Tennessee Valley region of far North Alabama, where dynamic support will be greater, and wind fields stronger. But, an isolated tornado can’t be ruled out down into Central Alabama.

*Greatest risk of severe storms will come from roughly 3:00 until 9:00 p.m.

This type of event is pretty common in Alabama in late April; no need to be alarmed or worried. Just pay attention to weather developments, and have a good way of hearing severe weather watches and warnings as they are needed. We will have frequent updates here on the blog.

SUNDAY: Interesting to note the guys at SPC have the southern half of Alabama in a “marginal” severe weather risk Sunday. A surface boundary will be somewhere around the middle of our state; along and south of that a few widely scattered showers and storms could develop, and they could be strong. But, for now, we will keep a dry forecast going for the northern half of the state. The NAM is printing a high of 86 degrees for Birmingham Sunday afternoon; it would be a pretty warm day.

The weather stays dry Monday with a high in the 70s.

TUESDAY/WEDNESDAY: The next wave in the jet will bring periods of rain to the state; the GFS is trend weaker and slower, hinting the bulk of the rain will come Tuesday evening through the day Wednesday. Again, the surface low is expected to pass south of here, meaning little if any severe weather risk. Drier air returns Thursday and Friday.

See the Weather Xtreme video for maps, graphics, and more details.

KBHM_2015042400_min_max_16

WEATHER BRAINS: Don’t forget you can listen to our weekly 90 minute netcast anytime on the web, or on iTunes. This is the show all about weather featuring many familiar voices, including our meteorologists here at ABC 33/40.

CONNECT: You can find me on all of the major social networks…

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I have a weather program this morning at Sulligent Elementary School in Lamar County…. be looking for the next Weather Xtreme video here by 4:00 this afternoon… enjoy the day!

Severe Storms Possible Saturday

| 2:36 pm April 23, 2015

THIS AFTERNOON: Lingering patches of light rain across Central Alabama will end soon, and the sky becomes mostly fair late tonight. As expected, temperatures are noticeably cooler across the northern half of the state today; in fact some spots are barely out of the 50s at mid-afternoon.

TOMORROW: Most of the day tomorrow will be dry; with a mix of sun and clouds we project a high in the mid 70s… just a small risk of afternoon shower. Then, tomorrow night, rain and storms will increase from the south as a warm front lifts northward. The latest high resolution NAM is now suggesting the best chance of rain holds off until after midnight tomorrow night, so while we sure can’t make any promises, you might get a baseball or softball game in tomorrow evening before the big rain comes.

SEVERE WEATHER POTENTIAL SATURDAY: A deep surface low will be over Missouri Saturday, supported by an upper trough lifting out of the Southwest U.S. Surface based instability values are now projected to rise to near 3,000 j/kg over West Alabama late Saturday afternoon, the most unstable values we have seen so far in 2015. The low level jet (around 5,000 feet) is expected to be in the 40 knot range, and there is a significant amount of speed and directional shear.

The NAM is suggesting EHI (Energy Helicity Index) values in the 3-5 unit range late Saturday afternoon over the northern third of Alabama.

NAM_221_2015042312_F60_EHI_3000_M

Some thoughts on the day:

*Storms could be in progress early Saturday morning, but only a marginal severe weather risk with those.

*There is a good chance we will have several hours of rain-free conditions Saturday, and the sun should be out at times pushing afternoon temperatures up into the low 80s (maybe even mid 80s over West Alabama).

*Storms should begin to develop during the peak of the daytime heating process Saturday afternoon, and those will be the ones with the highest severe weather potential.

*All modes of severe weather will be possible, including hail, damaging straight line winds, and a few tornadoes.

*The severe weather threat will end around midnight Saturday night as drier air begins to push in from the west.

The Storm Prediction Center has all of Alabama in the standard “slight” risk of severe weather for Saturday.

day3otlk_0730

SUNDAY/MONDAY: These two days will be dry and pleasant, with a high in the 77-82 degree range and a partly sunny sky both days.

TUESDAY/WEDNESDAY: The good news is that we are getting good model consistency in the idea of a surface low passing through South Alabama, meaning little if any severe weather issues for the northern half of the state on these two days. But, periods of rain and a few thunderstorms are likely, and the rain could be heavy at times. The high Tuesday will be in the 70s, but will drop into the 60s Wednesday.

See the Weather Xtreme video for maps, graphics, and more details.

WEATHER BRAINS: Don’t forget you can listen to our weekly 90 minute netcast anytime on the web, or on iTunes. This is the show all about weather featuring many familiar voices, including our meteorologists here at ABC 33/40.

CONNECT: You can find me on all of the major social networks…

Facebook
Twitter
Google Plus
Instagram

I had a great time today visiting with the students at Whitesboro Elementary School in Etowah County… be looking for them on the Pepsi KIDCAM today at 5:00 on ABC 33/40 News! The next Weather Xtreme video will be posted here by 7:00 a.m. tomorrow…

Some Rain Possible This Afternoon

| 6:37 am April 23, 2015

RADAR CHECK: Models have not done a good job handling the precipitation fields today; despite a surface front in the area, the radar is quiet this morning, and there is no rain in progress statewide. However, west of the state, there is a rather large mass of rain and thunderstorms over parts of Arkansas and Louisiana thanks to a wave embedded in the sub-tropical jet stream, and that wave is moving east. This means it now looks like the best chance of rain today will actually during during the afternoon hours (models had suggested the showers today would be this morning).

So… we will adjust the forecast accordingly and mention rain this afternoon, generally in the 12:00 noon to 6:00 p.m. time frame. There could be some thunder, but there is no significant risk of severe weather, and rain amounts should be under 1/2 inch. Best chance of rain will be south of a line from Vernon to Warrior to Alexandria… rain seems unlikely north of U.S. 278 (Hamilton to Cullman to Gadsden) where the air will be drier.

TOMORROW: Most of the day will be dry; some sun at times with a high in the mid 70s. An afternoon shower can’t be ruled out, but most of the rain will hold off until tomorrow night. High resolution NAM model output hints the rain begins sometime between 6:00 and 9:00 tomorrow night as a warm front lifts northward, and we will have periods of rain and thunderstorms through the night. The severe weather risk is fairly low tomorrow night, although a few stronger storms are certainly possible.

SATURDAY: The Storm Prediction Center has all 67 Alabama counties in the standard “slight” risk of severe weather…

day3otlk_0730

Here are some thoughts about Saturday’s weather…

*It won’t rain all day, and the sun could break out at times. The high res NAM suggests we could see storms early in the day, followed by a midday break in the rain, then more storms by late afternoon and into Saturday night.

*It will be a warm day, with a high at or just over 80 degrees. This will help to make the air unstable; surface based CAPE values are expected to exceed 2,000 j/kg by afternoon.

*Forecast parameters suggest all modes of severe weather will be possible, including hail, strong straight line winds, and a few isolated tornadoes.

*It is impossible to give you start/stop times for rain at any specific location… just understand where storms develop, they could be strong to severe.

There are many, many outdoor events going on, so just be sure you have a way of hearing watches and warnings.

SUNDAY/MONDAY: These two days looks dry and pleasant with highs in the 78-82 degree range. Eyes will be on another dynamic weather system off to the west, impacting Texas and some of the adjacent states.

TUESDAY/WEDNESDAY: That Texas system will impact Alabama on these days, but we have more questions than answers now. Both the GFS and the ECMWF have been trending southward with the surface low, and this would reduce any risk of severe weather for the northern two-thirds of Alabama, meaning the main issue here would be from heavy rain. We really need to get past the Saturday system to feel confident about telling you what will happen with this one. See the Weather Xtreme video for maps, graphics, and more details.

KBHM_2015042300_min_max_16

WEATHER BRAINS: Don’t forget you can listen to our weekly 90 minute netcast anytime on the web, or on iTunes. This is the show all about weather featuring many familiar voices, including our meteorologists here at ABC 33/40.

CONNECT: You can find me on all of the major social networks…

Facebook
Twitter
Google Plus
Instagram

I have a weather program this morning in northern Etowah County at Whitesboro Elementary School… be looking for the next Weather Xtreme video here by 4:00 this afternoon. Enjoy the day!

Showers Possible Late Tonight

| 3:37 pm April 22, 2015

RADAR CHECK: As you might expect with a good supply of sunshine, we have no showers on radar this afternoon, and a dry airmass is still in place across Alabama. Temperatures are mostly in the upper 70s, and to the north we are watching a cold front just south of I-40 in Tennessee. This front will push into Alabama later tonight, and it is still capable of producing a band of showers after midnight tonight into tomorrow morning.

The main window for showers will come from about 12:00 midnight tonight through 12:00 noon tomorrow, although we can’t rule out a stray shower in spots tomorrow afternoon. Amounts should be under 1/2 inch, and there is no risk of severe weather. Tomorrow will be cooler with a high in the mid to upper 60s over the northern third of the state.

FRIDAY: The day looks generally dry with a high in the low to mid 70s, but a few scattered showers could break out during the afternoon as a warm front begins to lift northward across the state. Rain and storms become widespread Friday night, and that rain could be heavy at times. The risk of severe weather Friday night is low, but not zero.

TWO SEVERE WEATHER SETUPS: This is the core of the spring tornado season, and sure enough it looks like we will have two severe weather threats over the next seven days.

THREAT NUMBER ONE: The first will come during the day Saturday. A surface low will be over Missouri, supported by an upper trough, and a very moist, unstable airmass will be in place. It won’t rain all day Saturday, and the sun could break out at times, but we will forecast a good chance of occasional showers and thunderstorms through the day and into the evening hours. Surface based CAPE values are forecast to exceed 2,000 j/kg by Saturday afternoon, and we are now seeing rather high storm relative helicity values advertised by the GFS (over 300 m2/s2), which could set the stage for rotating updrafts.

This this time, it looks like the core severe weather threat will come from 11:00 a.m. until 8:00 p.m. Saturday, and all modes of severe weather will be possible, including large hail, strong straight line winds, and a few tornadoes. This could, and probably will change as we get closer to the event, but everyone needs to understand severe weather is a distinct possibility Saturday.

sat_ehi

Sunday and Monday are looking dry and pleasant, with a good supply of sunshine both days and highs in the 78-82 degree range.

THREAT NUMBER TWO: The second severe weather threat will come in the Monday night-Tuesday time frame. A deep surface low will set up northwest of Alabama with a deep upper trough with strong wind fields. Early indications suggest this could be a significant threat, but keep in mind this is six days away, and it could easily change. Take a few minutes to watch the Weather Xtreme video for the maps, graphics, and more details.

WEATHER BRAINS: Don’t forget you can listen to our weekly 90 minute netcast anytime on the web, or on iTunes. This is the show all about weather featuring many familiar voices, including our meteorologists here at ABC 33/40.

CONNECT: You can find me on all of the major social networks…

Facebook
Twitter
Google Plus
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I enjoyed speaking this morning at the Jacksonville State University Administrative Conference… look for the next Weather Xtreme video here by 7:00 a.m. tomorrow…

Showers Return To Alabama Tonight

| 6:33 am April 22, 2015

MOSTLY DRY TODAY: Pretty chilly for late April this morning; we note that Vic Bell up at Black Creek, near Gadsden, is reporting 37 degrees just before daybreak. Fort Payne is also at 37. But, we warm nicely today with a high in the upper 70s this afternoon along with a partly sunny sky. We will mention a small risk of a shower late in the day, mainly north of Birmingham.

RAIN RETURNS TONIGHT/TOMORROW MORNING: Showers are more likely late tonight, especially after midnight, as a cold front approaches. Seems like the main window for the rain is from about 12:00 midnight tonight through 12:00 noon tomorrow. Some thunder is possible, but there is no risk of severe weather, and rain amounts should be 1/2 inch or less. The sky becomes partly sunny tomorrow afternoon as drier air works in, and the day will be cooler with a high in the upper 60s.

ACTIVE WEATHER FRIDAY THROUGH EARLY NEXT WEEK: Sure looks like we will have two setups for severe weather… you know we are in the core of the spring tornado season, and this is when we need to keep our eye on the ball.

The daytime hours on Friday look generally dry with only a small risk of an afternoon shower; we rise into the low 70s Friday afternoon. A northward moving warm front will bring rain and thunderstorms in here Friday night with potential for heavy rain. And, maybe a few strong storms as well.

SEVERE WEATHER SATURDAY? Models continue to show higher instability across our state Saturday, with surface based CAPE values exceeding 2,000 j/kg. This means air parcels are able to rise freely, one of the important variables needed for severe storm formation. The low level jet (5,000 feet off the ground) will be in the 40 knot range, and there will be some degree of shear in place with a surface low over Missouri and an approaching upper trough.

It won’t rain all day Saturday, and the sun might even break out at times pushing temperatures to near 80 degrees. But we will need to forecast occasional showers and storms during the day, with the potential for some storms to become strong to severe. I would suggest the primary threats will come from hail and strong gusty straight line winds, but an isolated tornado can’t be ruled out with the setup we see now.

SUNDAY: Drier air works in here, and this day should be nice with ample sunshine and a high in the 70s.

MORE SEVERE WEATHER EARLY NEXT WEEK: The GFS is now advertising a potent spring storm system, with a deep surface low over Missouri with support from a deep upper trough. Wind fields look impressive, and this could be a significant severe weather threat IF model output verifies. The core threat would be Monday night into Tuesday morning, but this could, and probably will change. No need to get worried about it now, but just something to watch. Take some time to watch the Weather Xtreme video for maps, graphics, and more details.

mon_night_s

KBHM_2015042200_min_max_16

WEATHER BRAINS: Don’t forget you can listen to our weekly 90 minute netcast anytime on the web, or on iTunes. This is the show all about weather featuring many familiar voices, including our meteorologists here at ABC 33/40.

CONNECT: You can find me on all of the major social networks…

Facebook
Twitter
Google Plus
Instagram

I will be speaking at the Jacksonville State University administrative conference this morning at the Oxford Civic Center… look for the next Weather Xtreme video here by 4:00 this afternoon. Enjoy the day!

Showers Return Later This Week

| 3:35 pm April 21, 2015

BLUE SKY: As advertised, this has been a spectacular spring day across the great state of Alabama with sunshine in full supply. Temperatures are generally in the 68-72 degree range, and the humidity levels are remaining very low.

Temperatures

TONIGHT/TOMORROW: The sky will remain fair tonight with lows mostly in the low 50s; colder valleys will reach the 40s again early tomorrow. Looks like we just about take out any risk of rain during the day tomorrow… the sky will be partly sunny with a high in the upper 70s. The chance of any one spot seeing a shower late in the day is only in the 10 percent range, not really high enough to mention in our formal forecast.

THURSDAY/FRIDAY: We expect a decent round of showers and storms late tomorrow night into Thursday morning; highest probability of getting wet comes from about midnight tomorrow night through 12:00 noon Thursday, but a few lingering showers are possible Thursday afternoon. It will be a bit cooler Thursday with a high around 70 degrees. Then, showers and storms will increase again late Friday and Friday night ahead of an upper trough and surface low approaching from the west. We reach the low 70s Friday afternoon.

THE ALABAMA WEEKEND: The surface low will still be northwest of Alabama Saturday, and the 12Z GFS has come in with higher instability values (surface based CAPE values over 2,000 j/kg). I don’t think it rains all day Saturday, and the best chance of showers and storms could very well come during the morning hours, but where storms do form that could pack a punch. A little too early to define the severe weather threat since models still are not in good agreement over the small scale features. A chance we reach the low to mid 80s Saturday afternoon.

Then, dry air returns Sunday with sunshine back in full supply along with a high in the mid 70s.

NEXT WEEK: Low confidence, but the GFS is back on the idea of a chance of showers and storms in Alabama Monday as a wave passes through; we will insert that risk in the forecast. Then, drier air returns Tuesday night and Wednesday. See the Weather Xtreme video for maps, graphics, and more details.

KBHM_2015042106_min_max_16

WEATHER BRAINS: Don’t forget you can listen to our weekly 90 minute netcast anytime on the web, or on iTunes. This is the show all about weather featuring many familiar voices, including our meteorologists here at ABC 33/40.

CONNECT: You can find me on all of the major social networks…

Facebook
Twitter
Google Plus
Instagram

I had a great time today visiting the 3rd graders at Englewood Elementary in Tuscaloosa, and the students at McElwain Christian Academy in Birmingham. Be looking for them on the Pepsi KIDCAM today at 5:00 and 6:00 on ABC 33/40 News! The next Weather Xtreme video will be posted here by 7:00 a.m. tomorrow…