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Office: LIX

FXUS64 KLIX 211807
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
1207 PM CST Wed Nov 21 2018

.AVIATION...

VFR conditions are expected to continue through Thursday afternoon
or 00z Friday. High and mid clouds will increase across the south
half of our forecast area affecting KHUM, KNEW, KMSY, KNBG amd
possibly KGPT. Some light rain is possible between 06z and 12z
Thursday for these sites but visibility restrictions are
anticipated. 18

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...None.
MS...None.
GM...None.
&&

$$



Office: LCH FXUS64 KLCH 211743 AFDLCH Area Forecast Discussion National Weather Service Lake Charles LA 1143 AM CST Wed Nov 21 2018 .DISCUSSION... 18Z TAFS && .AVIATION... High pressure centered over eastern Arkansas this afternoon will allow moderate northeasterly to easterly winds to prevail. Mostly clear skies will continue through the early afternoon with more dense VFR ceilings moving in from the west by this evening as an upper level disturbance crosses the region. Scattered showers are expected to develop around or after midnight, impacting the I-10 corridor terminals, before quickly coming to an end before sunrise. Jones && .PREV DISCUSSION... /issued 1044 AM CST Wed Nov 21 2018/ DISCUSSION... Wx map shows 1031mb high over NE TX/AR/N MS this morning, with northeast winds 5-10 mph inland, around 15 knots offshore. This is keeping rather cool conditions over the region with temperatures still in the lower to mid 50s. Forecasted afternoon highs in the lower 60s looks good. Visible satellite imagery showing thin cirrus streaming overhead, with the lower/mid level OVC layer over C/S TX slowly moving northeastward. This is expected to spread over SE TX later this afternoon, and the remainder of LA this evening with light rain developing. Ongoing forecast has this, no updates needed. DML PREV DISCUSSION... /issued 546 AM CST Wed Nov 21 2018/ DISCUSSION... For the 11/21/18 1200 UTC TAF package. AVIATION... VFR is expected to prevail through the period amid increasing high and mid level cloud cover that will yield areas of rain at KBPT and KLCH this evening into the overnight period. TEMPO MVFR VSBY restrictions for BR at KAEX for the first couple hours of the forecast. 13 PREV DISCUSSION... /issued 423 AM CST Wed Nov 21 2018/ SYNOPSIS... Sfc analysis shows high pres centered acrs NE TX/S AR/N LA. This was providing a light northeast flow over the area, with temperatures as of 4 AM mainly in the lower 40s with a few spots into the 30s. Meanwhile, recent WV imagery and UA analysis shows a split-flow regime over much of the CONUS west of the Mississippi, with zonal flow acrs TX into LA ahead of a weak shortwave crossing the SW. Moisture within the southern branch was streaming acrs old Mexico into the area, resulting in the passage of some thin CI over the region. 24 DISCUSSION... Dry weather is expected today, but clouds will begin to increase over the region from west to east late this aftn into the evening as the shortwave over the SW US approaches the area. Lift provided by the approaching disturbance will allow showers to increase and spread northeast into the area overnight. Some cyclogenesis will take place along the western end of an old frontal boundary over the Gulf of Mexico, but these features are expected to remain well offshore, and this will keep a cooler and more stable airmass in the lower levels. There have been few changes from the scenario noted yesterday morning, as moisture profiles over the area continue to look fairly modest with precip water values peaking near the seasonal average (around 0.8 inches) acrs much of the area, with higher values of an inch or more noted offshore. In addition, elevated instability will be minimal, and the risk for tstms will be low although an isolated clap of thunder cannot be ruled out for areas south of I-10 in Jefferson County as well as far SW LA. The highest rain chcs will also be confined to areas south of I-10, with rain chcs quickly tapering off Thanksgiving morning as the disturbance quickly exits to the east. Temperatures will be near or slightly cooler than normal with highs around 60 today and into the lower 60s Thursday. Overnight lows will fall into the lower and middle 40s. The progressive pattern aloft will keep things fairly active through the weekend as a series of disturbances and associated fronts move through the area. The first of these will arrive on Friday. This shortwave will cross TX and interact with the sfc low/trough off the southern TX coast, lifting it toward the area during the day Friday. This will help to bring better moisture over the area. Instability will likewise increase with the approach of the sfc low, but with the eastward track of the low expected to remain near the coast, inland penetration of the warm sector will be minimal, and thus instability and resulting tstms should remain elevated. This system will quickly move east with rain ending Friday night and dry weather expected for Saturday. Temperatures will trend warmer through the weekend as southerly winds develop during the day Saturday in response to lower pres developing over the high plains. A stronger system will emerge over the cntl high plains Saturday night, prompting cyclogenesis over the TX/OK panhandles. This system will shift eastward through the day Sunday, sweeping a cold front through the area as the sfc low lifts acrs the mid-MS Valley. Best dynamics should stay north of the area, and deeper moisture return will be delayed prior to the arrival of the front. Thus, the best chcs for showers and isolated storms will be limited to just offshore into southern portions of Acadiana. Rain chcs will come to an end Sunday evening as cool high pres settles southward into the area. With west to northwest flow developing behind the upper trough, dry weather is expected to for early next week. Temperatures will be cool with overnight lows in the upper 30s to lower 40s and highs in the 50s Monday and Tuesday. 24 MARINE... Lt to modt northeast winds can be expected through Thursday. Winds will strengthen slightly overnight, with exercise caution expected over the outer coastal waters. Winds will shift east then briefly southeast on Friday as low pres over the western Gulf moves east over the coastal waters. Offshore flow will resume Friday night into early Saturday behind the low, with onshore flow again developing during the day Saturday as low pres deepens over the southern plains. A series of upper level disturbances will bring a chance for showers on Wednesday night into early Thursday, and again on Friday. Offshore is expected by late Sunday with the passage of the next strong cold front. 24 && .PRELIMINARY POINT TEMPS/POPS... AEX 39 63 44 63 / 20 0 10 80 LCH 45 63 49 66 / 40 10 10 70 LFT 45 64 48 68 / 30 10 10 80 BPT 47 63 52 68 / 40 10 10 50 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...None. TX...None. GM...Small Craft Exercise Caution from 6 PM CST this evening through late tonight for GMZ470-472-475. && $$ AVIATION...66
Office: SHV FXUS64 KSHV 211928 AFDSHV Area Forecast Discussion National Weather Service Shreveport LA 128 PM CST Wed Nov 21 2018 .SHORT TERM.../Tonight through Thursday Night/ Weak shortwave movg across the TX Panhandle this aftn will approach our region later this aftn/evening. With high pressure still firmly anchored over the region, little to no low level moisture will be available to generate convection. Latest model runs indicate that some light shwrs could develop across our Deep E TX/W Central LA areas, so have maintained the ongoing PoP fcst, with all other areas remaining dry. Unseasonably cool airmass will remain in place through Thanksgiving Day, and any overnight shwrs will quickly push e of our area, leaving clearing skies. Sfc ridge to migrate ewd during the latter half of Thursday, as sly flow returns ahead of an ejecting trof. Subsequent increasing moisture/WAA will help hold our temps up in the 40s Thursday night. /12/ .LONG TERM.../Friday through Wednesday/ During Friday, expect a weak cold front to traverse the region along with a week short wave trough aloft to produce SCT showers and even isolated TSTMS. This front will push SE to the Gulf Coast through Saturday morning with a dry and stable airmass in its wake for this upcoming holiday weekend. Expect zonal flow aloft through the final work week of November as the wintertime subtropical jet appears to be developing early this season across the SRN U.S. Accordingly, we can expect quiet and dry weather in fast zonal flow across the region through month's end. Also this pattern is favorable for precipitation across the western U.S. and especially in CA where rain is certainly needed. /VIII/ && .PREV DISCUSSION... /issued 1134 AM CST Wed Nov 21 2018/ AVIATION... VFR conditions to prevail throughout the 18Z TAF pd, despite a passing upper level disturbance. Aside from some thickening mid and high clouds, KLFK may see a pd of light rain with no category reductions expected. Otherwise, winds will continue generally out of the e at around 5 kts during the daylight hours today and Thanksgiving Day, but will diminish to near-calm overnight tonight. /12/ && .PRELIMINARY POINT TEMPS/POPS... SHV 37 61 46 61 / 10 0 10 60 MLU 37 61 44 61 / 0 0 0 80 DEQ 34 59 43 57 / 0 0 10 70 TXK 35 60 44 58 / 0 0 10 60 ELD 34 60 43 59 / 0 0 10 80 TYR 38 60 47 64 / 10 0 10 50 GGG 36 60 46 63 / 10 0 10 60 LFK 40 61 48 66 / 40 0 10 50 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ 12/08