Severe wx threat 3-2/4-04, lookout Texas and Oklahoma
Posted: Tue Mar 02, 2004 2:38 pm
Good afternoon folks. A busy time still continues in the wake of yesterday's severe weather across northern Illinois and into parts of Wisconsin and lower Michigan. As we get started here this afternoon, we must talk about a few things.
#1 the tornado count is very low. We're talking only 11 tornadoes during this past winter season of '03-'04 across the United States. The previous record was 13 tornadoes set during the '1984-1985 winter season.
#2. In the state of Oklahoma, the last tornado report was on May 16th, 2003. From May 1-May 16, 2003, 59 tornadoes occurred in Oklahoma, which is the average number of tornadoes for an entire tornado season in the sooner state. Since May 16th, 2003 though, no tornadoes were reported. As a result, today is day #290 without tornadoes in the sooner state, which is an all time record number of days without tornadoes, which is really something. Don't expect that streak to last as we approach the 2004 severe weather season. In fact I think we could potentially end that streak in Oklahoma as early as Wednesday, but most likely Thursday where isolated tornadoes are possible. Wednesday would be day #291, Thursday day #292. It's possible we might not make it past #292 courtesy of this upcoming severe weather episode.
Today's severe threat is expected to be isolated compared to what is coming up over the next 2-3 days across the south central United States. The best chance for isolated severe storms today will be over the west central portion of Texas including the Abilene area. A warm front is expected to lift northward to a position at or near interstate 10 by early evening. North of the warm front, southeasterly winds will develop at the surface while winds aloft will be southwesterly. It's the shearing component, which is one ingredient to fire up isolated severe weather later today. Another ingredient is a combination of gulf moisture and a subtropical moisture plume moving in from the subtropical Pacific. Combine both the shearing and moisture component together, and the recipe will be set for isolated severe weather later today including potentially supercells. Damaging wind and large hail are the main threats. There is an outside risk of a tornado or two associated with any supercell that develops, mainly along and or just to the north of the warm front. However the key word today is isolated severe as the main upper level piece of energy is still well to the west off the southern California coast near the Catalina Islands.
On Wednesday, severe weather threat is expected to become more widespread as an upper level low begins to track towards the state of Texas. This upper low is progged to beover the northern Gulf of California and northern Mexico during the day on Wednesday. Ahead of that upper low, more subtropical moisture will combine with a diffluent flow or a splitting of the winds aloft. It's the split or V shape called diffluence, which oftens promotes additional lift. As a result, severe weather is expected to be more widespread on Wednesday from the Rio Grande Valley northward into portions of west and north central Texas. The main focus on Wednesday will be the Rio Grande Valley though as very strong forcing combined with steep lapse rates will contribute to a more widespread severe weather episode with potentially long lived supercells across the Rio Grande Valley and possibly into central Texas later in the day on Wednesday. While damaging winds and large hail are primary threats, we cannot rule out isolated tornadoes and very heavy rain of 1-2 inches or more. Flooding is another issue we're going to have to face with this system due to higher precipitable water values courtesy of moisture being advected northeast ward from the deep subtropics.
On Thursday, the danger from flooding and severe weather are not over. In fact, a more widespread severe weather episode is possible on Thursday as the upper level storm ejects northeastward into the south central United States. This upper disturbance will be accompanied by a significant surface cyclone or cyclogenesis. This surface low will deepen as it tracks northeast through the south central plains states throughout the day on Thursday. Along and ahead of this low, expect abundant mositure combined with some instability and dynamic forcing for severe weather including hail, high winds, and tornadoes. The areas most likely to see this during the day Thursday will be from eastern Texas northward into east central Oklahoma and portions of Arkansas and into Missouri.
On Thursday night, the focus shifts on the mid and upper Mississippi and lower Ohio Valley where damaging windstorms are possible through Thursday night.
The bottom line is stay abreast on the latest forecast from your local media or the national weather service. If a severe weather watch is issued, be ready and prepared to take immediate action and listen for later statements and possible warnings. If a warning is issued, take imediate action by heading to the lowest floor of your home or business. A basement is preferable and even if you feel a threat coming, take action immeidately. Further updates will be issued on this severe wx episode.
Jim
#1 the tornado count is very low. We're talking only 11 tornadoes during this past winter season of '03-'04 across the United States. The previous record was 13 tornadoes set during the '1984-1985 winter season.
#2. In the state of Oklahoma, the last tornado report was on May 16th, 2003. From May 1-May 16, 2003, 59 tornadoes occurred in Oklahoma, which is the average number of tornadoes for an entire tornado season in the sooner state. Since May 16th, 2003 though, no tornadoes were reported. As a result, today is day #290 without tornadoes in the sooner state, which is an all time record number of days without tornadoes, which is really something. Don't expect that streak to last as we approach the 2004 severe weather season. In fact I think we could potentially end that streak in Oklahoma as early as Wednesday, but most likely Thursday where isolated tornadoes are possible. Wednesday would be day #291, Thursday day #292. It's possible we might not make it past #292 courtesy of this upcoming severe weather episode.
Today's severe threat is expected to be isolated compared to what is coming up over the next 2-3 days across the south central United States. The best chance for isolated severe storms today will be over the west central portion of Texas including the Abilene area. A warm front is expected to lift northward to a position at or near interstate 10 by early evening. North of the warm front, southeasterly winds will develop at the surface while winds aloft will be southwesterly. It's the shearing component, which is one ingredient to fire up isolated severe weather later today. Another ingredient is a combination of gulf moisture and a subtropical moisture plume moving in from the subtropical Pacific. Combine both the shearing and moisture component together, and the recipe will be set for isolated severe weather later today including potentially supercells. Damaging wind and large hail are the main threats. There is an outside risk of a tornado or two associated with any supercell that develops, mainly along and or just to the north of the warm front. However the key word today is isolated severe as the main upper level piece of energy is still well to the west off the southern California coast near the Catalina Islands.
On Wednesday, severe weather threat is expected to become more widespread as an upper level low begins to track towards the state of Texas. This upper low is progged to beover the northern Gulf of California and northern Mexico during the day on Wednesday. Ahead of that upper low, more subtropical moisture will combine with a diffluent flow or a splitting of the winds aloft. It's the split or V shape called diffluence, which oftens promotes additional lift. As a result, severe weather is expected to be more widespread on Wednesday from the Rio Grande Valley northward into portions of west and north central Texas. The main focus on Wednesday will be the Rio Grande Valley though as very strong forcing combined with steep lapse rates will contribute to a more widespread severe weather episode with potentially long lived supercells across the Rio Grande Valley and possibly into central Texas later in the day on Wednesday. While damaging winds and large hail are primary threats, we cannot rule out isolated tornadoes and very heavy rain of 1-2 inches or more. Flooding is another issue we're going to have to face with this system due to higher precipitable water values courtesy of moisture being advected northeast ward from the deep subtropics.
On Thursday, the danger from flooding and severe weather are not over. In fact, a more widespread severe weather episode is possible on Thursday as the upper level storm ejects northeastward into the south central United States. This upper disturbance will be accompanied by a significant surface cyclone or cyclogenesis. This surface low will deepen as it tracks northeast through the south central plains states throughout the day on Thursday. Along and ahead of this low, expect abundant mositure combined with some instability and dynamic forcing for severe weather including hail, high winds, and tornadoes. The areas most likely to see this during the day Thursday will be from eastern Texas northward into east central Oklahoma and portions of Arkansas and into Missouri.
On Thursday night, the focus shifts on the mid and upper Mississippi and lower Ohio Valley where damaging windstorms are possible through Thursday night.
The bottom line is stay abreast on the latest forecast from your local media or the national weather service. If a severe weather watch is issued, be ready and prepared to take immediate action and listen for later statements and possible warnings. If a warning is issued, take imediate action by heading to the lowest floor of your home or business. A basement is preferable and even if you feel a threat coming, take action immeidately. Further updates will be issued on this severe wx episode.
Jim
