Sunrise 6:20 AM   Sunset 8:02 PM Moonrise 4:50 AM   Moonset 6:54 PM

  Print   HELP   Reset   Save   Recall  New

FXUS64 KSHV 070516 AFDSHV

Area Forecast Discussion National Weather Service Shreveport LA 1216 AM CDT Tue May 7 2024

New AVIATION

UPDATE
Issued at 1026 PM CDT Mon May 6 2024

No update is needed to the afternoon forecast package at this time. Small update to introduce the new tornado watch into the zones.

/44/

SHORT TERM
(This evening through Tuesday Night)
Issued at 311 PM CDT Mon May 6 2024

Widely scattered convection is finally beginning to develop across the region, in advance of a weak shortwave trough noted over E TX.
Some erosion/lifting of the morning stratus field has yielded strong insolation and an unstable air mass areawide, characteristic of SBCapes near or in excess of 3000 J/kg. Thus, additional scattered convection development is expected to continue through early evening, as this parent shortwave shifts NE through Srn AR/N LA before exiting. Some additional convection may linger a little longer though across SE OK/adjacent sections of SW AR, as a SWrly LLJ intensifies to 40-50kts along a low level theta-e axis ahead of the strongly negative tilt upper trough as it pivots through Cntrl and Ern OK into the Ozarks. Very strong forcing/instability along the Ewd advancing dryline will eventually lead to the development of multiple supercells over Wrn and Cntrl OK later this afternoon into the evening, which may consolidate into a linear line as it quickly advances ENE through Ern OK into the Ozarks overnight. Some of the latest CAMs continue to suggest that this line may near Nrn McCurtain County OK and the adjacent Nrn SW AR counties between 08-10Z, but will likely quickly weaken as the best forcing aloft shunts NE away from the area with the ejecting trough. Did place low to mid chance pops over this area for the expected decaying convection, which may be sustained by the SWrly LLJ and any residual instability remaining.

Hot, humid, and quiet conditions should return Tuesday, with mostly dry conditions expected as what's left of any mesoscale bndrys from the decaying morning convection eventually washing out with the onset of mixing. The sfc dry line is progged to mix E into SE OK, NW AR into or just E of the Ozarks during the afternoon, with some slightly drier air eventually mixing into SE OK/adjacent SW AR. What's left of this bndry should quickly begin to lift back N/wash out by Tuesday night, although it could still focus isolated convection overnight over SE OK/Nrn sections of SW AR especially with the onset of the SWrly LLJ. Deep lyr moisture is not expected to remain shallow, with no discernible perturbations progged in the SW flow before eventually reloading S of the closed low that is progged to spin over the Midwest.

15

LONG TERM
(Wednesday through next Sunday)
Issued at 311 PM CDT Mon May 6 2024

The aforementioned closed low is progged to send a weak cold front SE into the Srn Plains Wednesday, as it nears extreme NW AR into SE OK/N TX by late afternoon. The GFS/ECMWF suggest that a developing perturbation in the SW flow will help yield scattered convection development by mid and late afternoon from NE TX into SE OK/SW AR near and ahead of the front, coincident of very strong instability that will develop as sfc temps near/exceed 90 degrees.
H700-500 lapse rates are progged to be steep, ranging from 7.5-8.0 C/km, thus promoting very strong updraft growth within a zone of strong deep lyr shear. Thus, pending the strength of the perturbation in the SW flow, severe thunderstorms appear likely over these areas, where an Enhanced Risk has been outlined by SPC in the Day 3 Outlook. This convection should persist into the evening before shifting NE, with the attendant cold front drifting S into E TX/N LA by daybreak Thursday. Depending on whether the front temporarily stalls along/just S of the I-20 corridor Thursday or not, it appears that scattered convection will redevelop near the bndry which could again flare up/become severe, before finally shifting S of the area Thursday night.

Did highlight this area with mid/high chance pops Thursday afternoon/evening, before cooler and slightly drier air begins to spill S in wake of the cold fropa. The latest ensemble guidance suggests that mostly dry conditions will prevail Friday through most of the upcoming weekend, with near normal temps expected through the period. Some of the deterministic guidance do suggest that some weak perturbations may help enhance some convection development this weekend, although refinements to the forecast are likely in the coming days.

15

AVIATION
(06Z TAFS)
Issued at 1207 AM CDT Tue May 7 2024

MVFR ceilings rapidly returning northward from SE TX and SW LA into our airspace at this late hour this evening and thus, expect widespread MVFR ceilings to dominate much of our region through the predawn hours. Cannot rule out a narrow window of IFR ceilings at the LFK terminal a couple hours either side of sunrise but given the low level pressure gradient in place, feel like MVFR ceilings are the better bet vs IFR ceilings across our airspace through mid to late morning when ceilings return to low VFR variety. Latest HRRR wants to develop a narrow line of showers/Isolated TSRA from near LFK to SHV to ELD terminals and keeps this activity in the same general locations through the middle afternoon. Cannot find any support for this activity in other model output so will leave it out of this 06z TAF package and will reassess with the 12z package. Look for SSE to SSW winds today to be near 8-12kts sustained with gusts upwards of 20kts, especially across our NE TX terminal locations.

13

PRELIMINARY POINT TEMPS/POPS
SHV 89 74 91 72 / 0 0 20 40 MLU 88 72 91 70 / 10 0 10 40 DEQ 86 65 86 60 / 20 20 50 60 TXK 88 72 90 66 / 10 10 50 60 ELD 87 70 90 65 / 10 10 20 60 TYR 88 73 90 70 / 0 0 30 30 GGG 88 72 90 70 / 0 0 30 40 LFK 89 72 91 72 / 0 0 10 10

SHV WATCHES/WARNINGS/ADVISORIES
AR...None.
LA...None.
OK...None.
TX...None.

Full Color Weather Map

Link to Loop


Other links: GEOS-West     Contential US     Full GOES-East

Shreveport, LA,