


Area Forecast Discussion
Issued by NWS Shreveport, LA
Issued by NWS Shreveport, LA
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788 FXUS64 KSHV 032332 AFDSHV Area Forecast Discussion National Weather Service Shreveport LA 632 PM CDT Thu Apr 3 2025 ...New AVIATION... .SHORT TERM... (This evening through Friday Night) Issued at 314 PM CDT Thu Apr 3 2025 Another active afternoon of convection has already yielded a few severe thunderstorm warnings along the Red River straddling Texas and Oklahoma. These areas are still north of the sfc boundary so large hail has been the primary concern up to this point given the elevated nature of these storms and with temperatures only in the mid 50s. For this reason, Severe Tstm Watch 108 was issued for a handful of counties including Red River in NE TX, McCurtain in SE OK along with Sevier and Howard in SW AR to account for the large hail threat in these areas. Farther south toward I-30 where the boundary is roughly oriented, temperatures are in the lower to mid 60s. From there, temperatures quickly surge into the 70s and mostly the 80s farther SE where an increasingly expansive warm sector environment resides across the remainder of the region. Similar to what was observed around this time yesterday afternoon, weak CIN continues to limit convection south of the boundary so far this afternoon with our 19Z special sounding indicating a nearly eroded mid-level cap as compared to earlier this morning. With that mind, Tornado Watch 109 was also issued in concert with the Severe Watch with the former taking in our northern row of LA parishes and nearly all of East & Northeast TX. Given that sfc-based CAPE values are pushing 4500 J/kg per our 19Z sounding, storms should develop and mature quite rapidly once the cap is fully eroded by late afternoon. 0-6km shear is pushing 50 kts with similar values at 0-3km, yielding SRH around 400m2/s2 and possibly higher closer to the boundary. For this reason, a few strong tornadoes remain possible with any discrete supercells that may manage to develop. Large hail and damaging wind threats remain in place as well anywhere in the Tornado Watch area. What seems to be lacking in this equation is a strong forcing mechanism aloft as the SW flow regime hasn`t really yielded a significant shortwave across our region quite yet today. A rather strong impulse has now rounded the base of the primary trough axis still well to our west so it`s uncertain whether this feature will have time to make much difference in terms of increased forcing, thus additional cooling aloft. Regardless, sfc instability and mid-level lapse rates may prove to be strong enough to overcome the lack of stronger forcing aloft. Both Watch products are in effect through 10 PM with the severe threat diminishing thereafter. Unfortunately, we rinse and repeat all over again on Friday as the broader trough axis begins to slowly eject farther east from the Four Corners region. This should allow for added forcing across the NW half of the region, which is why SPC opted to upgrade much of this area to a Moderate Risk for Friday. Another important factor in this decision is a further northward shift of the sfc boundary that is expected overnight through the day Friday with the warm sector effectively encompassing our entire region by this time tomorrow. All modes will continue to be in play with tornado and large hail threats especially concerning in this unstable and highly sheared environment, most notably in the Moderate/Enhanced Risk areas. The severe threat will persist into the evening hours on Friday night before gradually trending downward after midnight. As if that weren`t enough, we still have to contend with the ever increasing heavy rainfall and flash flooding threat across much of our northern half. The current Flood Watch remains unchanged for this forecast update, and we will continue to monitor rain rates and amounts over the next 12-24 hours to see if further expansion of the Flood Watch toward the I-20 corridor becomes necessary. /19/ && .LONG TERM... (Saturday through next Wednesday) Issued at 314 PM CDT Thu Apr 3 2025 By Saturday, we finally get trough axis entering the Southern and Central Plains with one more round of severe weather and heavy rainfall to get through before this prolonged period of unsettled weather is over. The trough will serve to propel the sfc boundary eastward through the region by Saturday afternoon into the evening and overnight hours. This will maintain all modes once again with increasing shear and instability ahead of the front, especially if the timing pushes a bit later into the afternoon and early evening during peak heating times. Likewise, the flash flooding threat will persist as well across at least the northern half of the area with the Flood Watch in effect through early Sunday morning. All the convection and severe/flood threats should come to an end by daybreak on Sunday as the cold front pushes along the MS River. We will likely be dealing with lingering river flooding impacts into next week, but much of that will depend on exactly how much and where the heavy rainfall occurs. Beyond that, a quiet period of weather is expected for the early to middle part of next week with below normal temperatures and dry conditions which will be very welcome in the wake of our marathon of severe weather this week. /19/ && .AVIATION... (00Z TAFS) Issued at 623 PM CDT Thu Apr 3 2025 Stubborn boundary remains oriented west to east, and just north of the I-20 terminals this evening. Overrunning showers prevail north of the boundary, with a general BKN/OVC sub 5kft presentation on satellite airspace wide. Gusty S/SW winds remain a factor for the I-20 terminals and south, while fluid VRB looks to remain along and just north of the boundary. Expectation is for the boundary to drift back north again tomorrow, so the stronger southerlies will return for all terminals. Again, like today, SHRA will start the day with the return of possible severe mid to late afternoon and early evening TSRA where the boundary finalizes. Tomorrow, highest probs look to be within a region from KTYR/KGGG to KTXK. KNAPP && .SPOTTER INFORMATION STATEMENT... Issued at 425 AM CDT Thu Apr 3 2025 Spotter activation will be needed this afternoon and early evening across Northeast Texas, Southeast Oklahoma, Southwest Arkansas, and Northwest Louisiana for expected severe thunderstorms and heavy rainfall. /15/ && .PRELIMINARY POINT TEMPS/POPS... SHV 74 88 72 80 / 40 60 70 100 MLU 74 89 73 83 / 20 30 40 100 DEQ 58 79 59 68 / 80 90 100 100 TXK 64 84 67 75 / 70 80 90 100 ELD 65 86 67 79 / 50 70 70 100 TYR 68 83 62 71 / 50 80 100 100 GGG 70 85 66 75 / 50 80 90 100 LFK 73 86 70 79 / 20 40 60 100 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...Flood Watch through Sunday morning for ARZ050-051-059>061- 070>073. LA...None. OK...Flood Watch through Sunday morning for OKZ077. TX...Flood Watch through Sunday morning for TXZ096-097-108>112. && $$ SHORT TERM...19 LONG TERM....19 AVIATION...53