Area Forecast Discussion
Issued by NWS Lake Charles, LA
Issued by NWS Lake Charles, LA
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105 FXUS64 KLCH 021133 AFDLCH Area Forecast Discussion National Weather Service Lake Charles LA 633 AM CDT Tue Jul 2 2024 ...New AVIATION... .SHORT TERM... (Today through Thursday night) Issued at 310 AM CDT Tue Jul 2 2024 You wouldn`t think a difference of 1 or 2 degree dewpoints would feel all that different... this morning KLCH ASOS is reporting a Td of 76F, down 2 degrees from the last several mornings, and honestly it doesn`t feel as heavy or as humid outdoors. Folks heading out the door this morning will also wake up to dewpoints feeling *slightly* cooler than in days previous. Forward your thanks to a very weak "cold" frontal boundary that moved down through the region yesterday. Unfortunately hot, humid and stormy weather all return today for an encore performance as surface high pressure starts ridging across the northern GoM. Southerly winds in association with the high should pull ashore a weak easterly wave with showers, thunderstorms and humidity all to follow. Another similar wave should move across the region on Wednesday with numerous showers and thunderstorms expected. The 00z RAOB reported a PWAT of 2.31 inches with forecast models indicating values 2.50 to 2.90 inches moving inland with these waves today and tomorrow. These values are far more than plenty for very efficient warm rain processes to be in effect with convection. Not anticipating a widespread flash flooding concern, but showers may produce rain rates which could cause rapid low- lying area or urban flooding in vulnerable locations. Guidance also has deep CAPE profiles in place each afternoon. While the environment is not favorable for severe thunderstorms, a few isolated instances of strong to damaging wind gusts and frequent lightning will be possible this afternoon and Wednesday. Surface high ridge expands westward to southeast Louisiana on Thursday, ultimately shutting off wave action from the Gulf. This should allow for a semi-normal day of more-typical diurnally driven and scattered afternoon convection. Convection should come to an end with sundown allowing for holiday celebrations to commence. Any stronger storms could linger an hour or two after sundown, but these should be fairly limited in nature. Temperatures today will be the hottest of the short term period. Daytime high temps should top out in the mid to upper 90s across the entire forecast area with those north of I-10 potentially seeing 99 to 100F today. Combined with humidity, heat indices will rocket into the 100s quickly after sunrise. A Heat Advisory is in effect for coastal Texas and extreme southwest Louisiana with HIs up to 111F possible; inland Texas, central Louisiana and zones along the Atchafalaya are in an Excessive Heat Warning for HIs upwards of 116F. Areas where moisture pools along the surface will see those much higher real-feel values. Anyone who is outdoors today should heed heat precautions closely. Check on neighbors, vulnerable groups, and outdoor animals, take frequent breaks if outdoors, don`t leave children unattended in vehicles, and know the signs of heat stress in the body. Rain chances should keep temperatures in check Wednesday and Thursday. While temps will warm in to the 90s each day, confidence of hitting Heat Advisory criteria is low. An Advisory will be issued as needed. 11/Calhoun && .LONG TERM... (Friday through Tuesday) Issued at 310 AM CDT Tue Jul 2 2024 The long term begins Friday with the area beginning to see the influence of a digging trof over the center of the country, with the previously prevailing ridge significantly weakened along the Gulf Coast. Meanwhile, sfc high pressure is forecast to remain centered over the ern Gulf, maintaining a srly low-level flow across the region...although it must be noted that a weak sfc front is progged to be approaching the region from the north. With forecast soundings showing decent moisture (mean RH values again around 60 percent and PWAT values upwards of 2.1 inches), we should once again see diurnal convection break out with heating, fueled along by developing mesoscale features. As seems to be the norm these days, highest rain chances linger over the sern zones/Atchafalaya Basin where the best moisture is progged. The cntl CONUS trof and the approaching frontal feature look to combine with the persistent good moisture to lead to a higher coverage in showers/storms for Saturday. Latest guidance has been showing a more nwd trend with the eventual track of TC Beryl, with the GFS now showing a landfall along the lower TX coast with a recurve nwd along the TX cstl plain into Monday. Likewise, the GFS ensemble members have also shown quite the right turn in their eventual tracks over the past 24 hours. However the latest NHC track lies more in the center of the guidance envelope, albeit still with a rightward adjustment from this time yesterday. Stay tuned. Forecast highs in the long term continue to run in the lower/mid 90s each day. Peak heat index values generally look to stay below advisory criteria at this time. 25 && .AVIATION... (12Z TAFS) Issued at 624 AM CDT Tue Jul 2 2024 Expecting somewhat similar weather today as was observed yesterday. Boundary which brought showers and thunderstorms to the area yesterday is still sitting near the region and will get swept north today. The weakness associated with this boundary will spark off another round of scattered convection after 19Z. With or near thunderstorms expect heavy downpours, frequent lightning and turbulent winds. MVFR clouds are beginning to develop and will prevail through the afternoon and evening. Variable winds should become south-southeasterly and prevail that way during the afternoon. Conditions will improve with sundown as diurnal processes quiet for the night. Lingering storms will diminish after 00Z, ceilings will lift to VFR and winds will become variable once again. Some isolated ground fog may develop after 06Z, particularly where rainfall occurs today. This should not impact terminals more than perhaps an hour or two of VIS to 5 to 6 SM from 09 to 11Z. 11/Calhoun && .MARINE... Issued at 310 AM CDT Tue Jul 2 2024 Light offshore winds will turn onshore again this morning as high pressure begins ridging across the northeast GoM, washing northward the boundary previous placed over coastal waters. A series of weak easterly waves moving from south to north into south Louisiana will bring about scattered to numerous showers and thunderstorms today and Wednesday. Weakness aloft is established Thursday and beyond allowing for the return of normal diurnally driven showers and thunderstorms. Fairly light southerly flow and low seas will prevail until the weekend. && .PRELIMINARY POINT TEMPS/POPS... AEX 99 77 96 75 / 10 0 40 0 LCH 95 80 91 79 / 40 10 60 10 LFT 98 80 93 79 / 50 10 80 10 BPT 96 79 94 79 / 20 10 40 10 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...Excessive Heat Warning from 11 AM this morning to 7 PM CDT this evening for LAZ027>029-033-044-045-055-152>154-252>254. Heat Advisory from 11 AM this morning to 7 PM CDT this evening for LAZ030>032-073-074-141>143-241>243. TX...Excessive Heat Warning from 11 AM this morning to 7 PM CDT this evening for TXZ180-259-260. Heat Advisory from 11 AM this morning to 7 PM CDT this evening for TXZ201-261-262-515-516-615-616. GM...None. && $$ SHORT TERM...11 LONG TERM....25 AVIATION...11