ISOLATED SEVERE WEATHER POSSIBLE IN THE DELTA REGION OF NORTHEASTERN LA, SOUTHEAST ARKANSAS, FAR WESTERN MS FRIDAY AFTERNOON INTO FRIDAY NIGHT..
The low-pressure system on Friday Morning is expected to be rather strong, however will weaken as it pushes east and this will be limiting factor for the event on Friday. Given the weakening low pressure the lift will decrease rather significantly for much of the day which poses a question on storm development on Friday in much of the state. It’s likely that the warm-front moving in the morning will have some elevated showers and perhaps a t-storm during the morning into the early afternoon moving across the region given the lift and moisture convergence.
The westerly winds aloft will lead to warmer temperatures aloft leading to a strong cap, and we will need either another strong lifting mechanism or considerable day-time heating to erode the cap. A small short-wave moving through the state, and this coupled with day-time heating should allow for some t-storm development in the Eastern part of the state, however more likely development isolated to scattered storm development in Southeast AR/Northern LA/far Western MS. I am increasing in confidence that some development will occur, but a little uncertain on the severe weather threat.
Given the instability values on the order of 1,000-2,000 CAPE *some models have 2,500 CAPE**Strongly unstable in Southeastern AR, Northern LA, Western MS combined with sufficient wind shear which should allow for a few strong thunderstorms to develop during the afternoon into the night-time hours, and many models are showing instability to remain through the early overnight hours. Given the weaker lift and forcing the severe weather threat will be hampered somewhat, however a few isolated to scattered thunderstorms in a favorable environment may be able to rotate supporting primarily a threat of large hail, however damaging winds and a tornado will be possible within the stronger storms.
The tornado threat is in question, however with strong southeast winds in the delta region funneling from the Gulf of Mexico and the presence of mid-upper 60 dews and temperatures near 80 F with slightly more stable air further east. A zone of severe weather looks reasonable with all modes possible in area in Northeastern LA, Southeastern AR and Far Western MS, so I would watch out from late afternoon into the mid-evening. I am very curious to see higher-resolution models such as the Extended-HRRR models on Thursday Night.
Further West…The atmosphere will likely remain essentially capped on Friday with atmospheric conditions likely more stable, with westerly winds despite warm tempo. Given the lower dew-points and the westerly winds…The dry-line is likely not to fire any development, however there is a low/marginal risk of development of storms to occur should cap be eroded by chance. The environment will supportive of some large hail should this occur, but currently appears unlikely.
Most of the state will remain rain-free with mix of clouds and sun with warm and breezy conditions, with western half of the state possibly reaching into the mid-upper 70s, with some low 80s. Temperatures are likely to be in the 70s across the entire state on Friday for max highs. Dew-points will be considerably higher than they are on Thursday for sure. SUNDAY STORM POTENTIAL…
AT LEAST SOME SEVERE WEATHER POSSIBLE..A MORE ORGANIZED SEVERE WEATHER IS POSSIBLE IF ALL INGREDIENTS ALIGN FOR A GOOD PORTION OF THE STATE FAVORING THE ARKLATEX/ARKLAMISS AND SOUTHERN AR
The latest consensus of the modeling is indicating a negative tilted short wave which means stronger lift, dynamics, and a higher chance of moisture to be pulled north. The activity may start Saturday Night along northern TX where a marginal threat of severe weather given capping issues, however isolated large hail is possible near the DFW area on Saturday Night as a few storms may develop along the dry-line and push east-northeast into SE OK/SW AR on Sunday Morning and rapidly push northeast. Given the strong upper level shear and increasing moisture, instability…A cluster of thunderstorms possibly with mixed storm modes is anticipated to possibly develop to the west and push east/northeast with the possibility of strong to severe thunderstorms for a good portion of Southern ½ of AR, Northeastern TX, Northern LA, and likely may extend into the Arklamiss region for Sunday Afternoon and into Sunday Night.
The Euro is indicating a rather concerning scenario with a secondary surface low to develop enhancing wind shear, instability, moisture across Southern AR/Arklatex region Sunday Evening, and if this were to occur..The threat would be greatly enhanced with all modes of severe wx possible on Sunday Evening across particularly the Arklatex region into the Arklamiss region.
This is what we are watching regarding Sunday, and will have updates as data becomes more available.