Area Forecast Discussion
Issued by NWS Lake Charles, LA
Issued by NWS Lake Charles, LA
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151 FXUS64 KLCH 251958 AFDLCH Area Forecast Discussion National Weather Service Lake Charles LA 258 PM CDT Sat May 25 2024 ...New SHORT TERM, LONG TERM, MARINE... .SHORT TERM... (Tonight through Monday night) Issued at 255 PM CDT Sat May 25 2024 The Memorial Day holiday weekend is starting off with some unseasonably hot and humid conditions. Just mainly scattered diurnal clouds have formed this afternoon, however with a cap in place, no significant shower activity is forming. With the lack of clouds, and modest south winds pumping in low level Gulf moisture, air temperatures are in the upper 80s to mid 90s, with dew points still in the mid 70s, allowing the heat index reading at reliable observation sites to range from near 100F to 107F. A very similar pattern will hold into tomorrow with high pressure ridging in from the east allowing southerly flow to bring in Gulf moisture to allow for high dew points and humidity. Upper level ridge will provide cap to keep away any shower and allow for enough sunshine for temperatures again to be from near 90F to the mid 90s, and with that heat index values from 100F to 107F which are just below the local heat advisory criteria. At night and early morning, light winds may allow the high humidity to combine with particles from residual agricultural smoke for some patchy fog/haze to form, however only light visibility restrictions are expected. Monday/Memorial Day, the forecast is a little more tricky. The surface ridge will still provide winds off the Gulf for plenty of humidity and high dew points. However, the upper level ridge centered over Old Mexico, begins to retreat to the southwest some and this will cause a flattening of the upper level ridge over the forecast area. A short wave moving across during this time might be able to push a weak surface boundary, or convective outflow from convection to the north into the forecast area and clash with the moist unstable environment to allow for a chance for showers and thunderstorms. With the uncertainty of the timing of any features and dropping down from the northwest and how strong the surface boundary will be will only keep a slight chance for showers or storms in the afternoon into the night. SPC does have the area outlooked in a Marginal Risk for severe storms during that time frame. However, with such a small chance for storms, it may be one of those situations with favorable CAPE, mid level shear, and mid level lapse rate, that if an isolated storm develops it will produce strong downburst winds and/or large hail. What is becoming a little more certain is the heat for Memorial Day. Using a combination of CONSMOS and 50th percentile of NBM, afternoon temperatures will be in the mid 90s, combined with dew points in the mid 70s, afternoon heat index values are looking more likely in the 105F to 110F range. Therefore, the first Heat Advisory of the 2024 summer season may have to be issued, especially for portions of southeast Texas where the apparent temperature tool is giving solid readings between 108F and 110F. Rua && .LONG TERM... (Tuesday through next Friday) Issued at 255 PM CDT Sat May 25 2024 On Tuesday, a weak frontal boundary will slowly push south across the CWA through the day, allowing for winds to briefly become more ENE to E. Aloft, Mid level troughing will be over the Great Lakes while ridging remains to our south from Mexico to FL, resulting in a mainly zonal flow overhead. Tuesday looks to be another hot and humid day, with highs reaching into the low to mid 90s, while heat indices will peak in the mid 90s to lower 100s. As the boundary sags through the area on Tuesday, the first in a series of weak disturbances passing overhead may be able to induce some isolated afternoon convection. Moving into the second half of the week the boundary moves offshore and becomes increasingly washed out, as surface winds become southeasterly again on Wednesday. A small shot of "cooler" air is however, expected to arrive late Tuesday, and although it won`t actually feel any cooler it should bring temps back to near seasonal norms for the later half of the forecast period. Daytime highs should generally range from the low 80s to near 90 from Wed through Sat, while overnight lows are expected to fall into the upper 60s inland to mid 70s at the coast. In addition, at least small POPs return to the forecast each day through the later part of the week, as moisture remains elevated overhead and a couple more weak disturbances pass overhead aloft helping to induce afternoon convection. Overall, doesn`t look like any one day will bring better rain chances than the other, with POPs generally around 20% or so each afternoon for the time being. 17 && .AVIATION... (18Z TAFS) Issued at 1228 PM CDT Sat May 25 2024 The remainder of the afternoon looks like VFR conditions as skies should be scattered and any ceilings that may from will be at VFR levels. Southerly winds will be a little breezy at times with occasional gusts to near 20 knots. Tonight, light south winds will prevail, with some low clouds forming during the evening hours under the cap at MVFR levels which will continue into the overnight. Particles from residual agricultural smoke may combine with the high humidity to produce brief light visibility restrictions from patchy fog/haze, although conditions should remain at MVFR levels. Rua && .MARINE... Issued at 255 PM CDT Sat May 25 2024 Surface high pressure located off to the east of the Florida coast will continue to ridge into the coastal waters and dominate the low levels for the period. This will allow for mainly southerly wind flow to persist through the period. Winds will increase some tonight into Sunday as low pressure forms over the Plains with winds approaching 20 knots and thus small craft exercise caution will be headlined during that period. An upper level ridge is expected to hold over the northern Gulf of Mexico and no shower or thunderstorm activity is expected through the holiday weekend. Rua && .PRELIMINARY POINT TEMPS/POPS... AEX 74 92 74 95 / 0 0 10 10 LCH 77 88 78 93 / 0 0 0 10 LFT 77 91 78 94 / 0 0 0 10 BPT 77 90 79 94 / 0 0 0 10 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...None. TX...None. GM...None. && $$ SHORT TERM...07 LONG TERM....17 AVIATION...07