272 FXUS64 KBRO 070528 AAC AFDBRO Area Forecast Discussion...UPDATED National Weather Service Brownsville TX 1228 AM CDT Sun Nov 7 2021 .DISCUSSION...Updated for latest aviation discussion below. && .AVIATION...Satellite images and surface observations indicate clear skies across the CWA late tonight. Expect some patchy ground fog to develop across portions of the Rio Grande Valley early Sunday morning as clear skies and calm winds allow fog to develop providing brief MVFR conditions. Otherwise...VFR conditions will prevail across the area the rest of tonight into Sun morning with the 500mb ridge across Texas continuing to provide subsidence across south Texas tonight into Sunday. && .PREV DISCUSSION... /issued 612 PM CDT Sat Nov 6 2021/ DISCUSSION...Updated for latest aviation discussion below. AVIATION...VFR conditions will continue to prevail through the TAF period across all terminals. This evening and overnight northeasterly winds will become more variable but continue to remain light before becoming more easterly on Sunday. Some patchy fog may form across far northwestern portions of the CWA overnight but should remain north and west of BRO, HRL and MFE. PREV DISCUSSION... /issued 348 PM CDT Sat Nov 6 2021/ DISCUSSION...Have added a coastal flood statement from 5 PM this evening until 10 PM this evening. Astronomical tides will lead to isolated minor flooding in spots this evening. The best time frame will be right around high tide, which occurs at 7:38 this evening. PREV DISCUSSION... /issued 246 PM CDT Sat Nov 6 2021/ SHORT TERM (Tonight through Sunday Night): Mid-level ridge situated over the Central Plains region provides subsidence across southern Texas through most of the short term period keeping us rain-free. Light winds will stay northeast to easterly with temperatures still below normal through Sunday night with highs in the upper 70s to lower 80s and lows in the mid 50s. However, dewpoints will continue to steadily increase throughout the period. Light winds and dewpoints in the lower 50s will increase our chances for patchy fog in the northern Ranchlands for Sunday morning expected to last from 4AM to 7AM (09-12z). For overnight Sunday into Monday, the ridge will start to move east out of the area towards the Ohio River Valley. A 500mb shortwave trough forms over Central Texas as the ridge exits allowing for light southeasterly onshore flow to return late Sunday night and bringing our dewpoints up into the upper 50s. The slight increase in low-level moisture for Monday morning increases the potential for patchy fog over a larger area of the CWA mostly over Zapata, Jim Hogg, Brooks, and Starr counties. The patchy fog is expected to last from 4AM to 7AM (09-12z). LONG TERM (Monday through Saturday): An H5 ridge will be in place over deep South Texas and the Northwest Gulf of Mexico to open the long term period. High pressure will be over the Lower Mississippi Valley. Thus, seasonal weather will be the main message from early to mid next week. Steady southeast winds will work to bring moisture into the region, with cloudiness and temperatures trending slowly upward. As ridging and high pressure shift to the east, mid level troughing will take over in the High Plains Tuesday, moving over East Texas Wednesday with the base of the axis moving over the CWA. A cold front will enter Texas and move southeast into central Texas on Wednesday as well. Rain chances will increase over the marine areas Wednesday into Thursday as the front tries to push through the local area. The GFS and the ECMWF present slightly different solutions for the end of the week. A deep parent low will move into the Great Lakes area on Thursday, but the GFS surface front will struggle to make a big push through the CWA. Upstream ridging will build over the West late in the week, and high pressure will continue to filter out of the Desert Southwest and over Texas. In the mean time a different source of high pressure will flow south over the Plains and will perhaps have better luck getting to the mouth of the RGV, but not until Saturday. The ECMWF is a little better with bringing a Thursday night to Friday front through the RGV, wind- wise, and hanging on to the northeast winds into Saturday. Used the NBM this cycle, noting that it seems to have a bit more of the ECMWF flavor. The actual guidance numbers between the two models are similar. There could be a slight fire weather concern on Friday if drier air does move into the region, with Friday afternoon relative humidity values dipping into the teens. Am not super confident with the threat right now, other than to note a small uptick in wildfire growth and spread potential on Friday for now. MARINE: Tonight through Sunday Night...Light easterly flow continues until overnight Sunday. As the ridge moves out of the area overnight Sunday into Monday, winds turn southeasterly but stay light. Seas will stay calm around 2 to 3 feet as the pressure gradient remains weak along the lower Texas coast. Monday through Thursday Night...Light to moderate southeast to south winds and low to moderate seas will prevail through mid week. A cold front, if it makes it through the area, may cause winds to shift to north Thursday night, and will bring scattered showers and thunderstorms to the coastal waters. && .PRELIMINARY POINT TEMPS/POPS... BAYVIEW/PORT ISABEL 78 62 81 65 / 0 0 0 0 BROWNSVILLE 81 63 84 65 / 0 0 0 0 HARLINGEN 80 59 83 62 / 0 0 0 0 MCALLEN 81 60 85 62 / 0 0 0 0 RIO GRANDE CITY 82 56 86 62 / 0 0 0 0 SOUTH PADRE ISLAND 75 71 77 73 / 0 0 0 0 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ This product is also available on the web at: https://weather.gov/rgv 61-Castillo/58-Reese