060 FXUS64 KBRO 252342 AAA AFDBRO Area Forecast Discussion...UPDATED National Weather Service Brownsville TX 642 PM CDT Sat Jul 25 2020 ...00z Aviation Update... .DISCUSSION...Updated for latest aviation discussion below. && .AVIATION...Flying conditions continue to be very adverse across Deep South Texas as Hurricane Hanna makes landfall across coastal Kenedy County. Latest surface observations across the region show generally MVFR ceilings in place, with a few VFR observations. The main concern, other than the various flight rules, are the very gusty winds occurring at the surface and just above the surface. Gusts have generally been around 40-50 knots at MFE, HRL, and BRO over the past few hours. Kept LLWS for all the the TAF sites through most of Sunday morning. As Hanna continues to move inland and moves more southwest, winds will turn more southerly to southeasterly and increase further overnight tonight, especially at HRL and MFE. Went ahead and removed TS out of all of the TAFs with this update. There may be a few rumbles of thunder over the next 24 hours, but Hanna is not producing much lightning right. Will update the forecast if this changes. Overall conditions will improve east to west by midday tomorrow, with rain gradually diminishing in the afternoon, becoming more showery and winds decreasing. && .PREV DISCUSSION... /issued 502 PM CDT Sat Jul 25 2020/ ..HURRICANE HANNA MAKING LANDFALL... SHORT TERM (Tonight through Sunday Night): Hurricane Hanna is in the process of transitioning from the western Gulf of Mexico to the inland areas of Deep South Texas and the Rio Grand Valley, and a plethora of Watches, Warnings, and Advisories (Hurricane Warning, Tropical Storm Warning, Storm Surge Warning, Flash Flood Watch, Coastal Flood Advisory, High Surf Advisory) are in effect within the BRO CWFA. Conditions will deteriorate from now through the overnight hours as Hanna treks west-southwest across the region. Although Hanna is forecast to be just across the Rio Grande River in Mexico around sunrise Sunday, additional showers and thunderstorms moving inland on Sunday through Sunday night could exacerbate any flooding that develops tonight within Deep South Texas and the Rio Grande Valley. LONG TERM (Monday through Saturday): A general elongated 500 mb trough axis will remain in place across Deep South TX and the RGV from Mon through Wed. This will combine with leftover tropical moisture from the remnants of Hanna to maintain the conv chcs during the first half of next week. The 500 mb ridging will start rebuilding over the TX Coastline and the RGV during the latter half of the week allowing for hotter temps and lower conv chcs. The GFS wants to hold on to the pops a bit longer versus the ECMWF which shuts down the pops pretty quickly after Wed. MARINE (Now through Sunday Night): Buoy 42020 reported southeast winds around 52 knots gusting to around 70 knots with seas of 21 feet with a period of 9 seconds at 1450 CDT/1950 UTC. Dangerous marine conditions are expected tonight through Sunday as Hurricane Hanna transitions from the open waters of the Lower Texas Coast to the inland areas of Deep South Texas and the Rio Grande Valley. Although winds and seas will improve markedly for Sunday night, a Small Craft Advisory may still be needed for the Laguna Madre and Gulf of Mexico waters from 0 to 60 nautical miles offshore due to remaining strong winds and rough seas. Monday through Thursday: Surface ridging over the Gulf of Mex will maintain a general light to moderate onshore flow pattern along the lower TX coastline next week. Some of the Gulf swells may experience SCA swells into Mon with conditions improving afterwards. Some SCEC swells may linger across the Gulf waters through Thursday. && .PRELIMINARY POINT TEMPS/POPS... BAYVIEW/PORT ISABEL 87 77 87 80 / 100 100 80 60 BROWNSVILLE 87 78 86 80 / 100 90 80 60 HARLINGEN 86 77 85 78 / 100 100 80 70 MCALLEN 88 77 83 78 / 100 100 90 70 RIO GRANDE CITY 92 75 84 76 / 100 100 80 70 SOUTH PADRE ISLAND 85 79 85 82 / 100 90 80 60 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...Hurricane Warning for TXZ250-251-254-256-351. Tropical Storm Warning for TXZ248-249-252-253-255-257-353. Flash Flood Watch through Sunday evening for TXZ248>257-351-353. High Rip Current Risk through Monday morning for TXZ256-257. Coastal Flood Advisory until 7 PM CDT Sunday for TXZ256-257. High Surf Advisory until 9 AM CDT Monday for TXZ256-257. GM...Hurricane Warning for GMZ132-135-150-155-170-175. Tropical Storm Warning for GMZ130. && $$ This product is also available on the web at: HTTP://WEATHER.GOV/RGV Aviation...67-Mejia